Sports Medicine

ABSTRACT

Soccer (football) is a complex contact sport with a substantial risk of injury. As injury surveillance is the first step of the injury prevention paradigm, soccer epidemiology is well reported in the existing literature, but less is known about the actual role of player position on the general injury risk.

The goal of this study is to present the existing evidence regarding the influence of player’s position on general injury risk in male soccer.

A systematic review of the Medline database was carried out. Only English written studies on male soccer and citing playing position as a possible determinant of injury risk were included. One hundred and two full texts were evaluated for eligibility, and 11 studies were selected for the qualitative synthesis.

Of the 11 studies included in the systematic review, 5 didn’t find any significant correlation with between player’s position and general injury risk, while the remaining 6 studies found player’s position to be correlated with injury risk, with mixed findings depending on each study. The most consistent finding was a tendency for goalkeepers (GKs) to sustain less injuries compared to outfield players. When considering only the studies reporting just the match injury risk, forwards seemed to be at higher risk, even if there wasn’t a complete agreement.

Few studies have evaluated a possible effect of playing position on general injury risk in male soccer. There is no agreement if weather or not different playing positions are associated to a higher injury risk. GKs seem to be at lower risk of injury when compared to outfield players.

Continue to: Soccer, known worldwide as football, is the most...

Soccer, known worldwide as football, is the most common practiced sport worldwide. Soccer is also a complex contact sport with a substantial injury risk,¹ that is well documented in the current literature. According to a recent systematic review, general injury incidence in male soccer ranged from 2.0 injuries to 19.4 injuries per 1000 hours of exposure in youth male soccer and from 2.48 injuries to 9.4 injuries per 1000 hours of exposure in elite male soccer.¹ It is also well established that the injury risk is greater in matches than training.¹ Soccer’s injuries are well known to be a socioeconomic burden for elite, youth, and recreational players.² Different authors have underlined the problem that nowadays the game is faster, and players need to have a better physical performance as they are subjected to important efforts both metabolically and biomechanically during match play. In the last decades, thanks to different research groups involved with professional soccer,³ there has been an increasing interest in soccer injuries’ epidemiology and for preventative measures.⁴ A deep comprehension of injury epidemiology is in fact the first necessary step for successful preventative measures. Regarding a possible correlation between playing position and injury incidence, there is a lack of consensus in the literature. Player position (goalkeeper [GK], defenders, midfielder [MF], or striker) may affect injury risk, as different roles are associated to different intensity during match play⁵ and experience different combination of anticipated or non-anticipated movement patterns.⁶ Previous authors underlined that few studies have evaluated a possible influence of playing position on injury incidence and severity.⁷

The main goal of this systematic review is to present the existing evidence regarding the influence of player position on injury incidence in male soccer and to present practical considerations on each field position in relation to the injury’s risk.

METHODS

DATA SOURCES AND SELECTION CRITERIA

We searched the Medline database for key terms and their variations to identify appropriate studies on injury epidemiology in soccer and specific player position influence. The keywords included: injury epidemiology soccer [OR] injury epidemiology football; position specific injury epidemiology soccer [OR] football. We limited our search to originally published English-language research articles.

Relevant data were extracted for study characteristics to ensure the included studies met certain criteria. The inclusion criteria were prospective design with minimum 6-month observational period, exclusively male soccer players’ cohorts, reported injury incidence, and documented player position in correlation with a measure of injury risk.

As stated above, we only included studies on male soccer. We also did not consider studies limited to a single injury type, considering only studies analyzing and documenting all injuries. We did not exclude studies on youth soccer but we didn’t consider studies on ≥2 more sports or mixed male and female studies.

Data were extracted by an author (FDV) and qualitatively controlled by another one (BM). Controversy were solved through discussion or confrontation with another author (LL).

Results of the included studies are presented only qualitatively because of different methodologies we encountered in documenting the potential effects of player’s role. Some studies reported differences in injury incidence within groups, others reported the proportion of injuries for each subgroup.  

Continue to: RESULTS...

 

 

RESULTS

STUDY SELECTION

Of the 1609 potential items we found in the existing literature, 102 full-text articles were screened for eligibility. Only 11 papers met the inclusion criteria and were included in the systematic review, including 2 studies on youth soccer and 9 studies on adult soccer (Figure 1). Five of the selected studies tracked only match injuries, while the remaining 6 studies presented data on both match and training injuries. As a matter of fact, the effect of player position was not so commonly evaluated or at least reported in the existing literature. Studies’ characteristics and main findings regarding player’s position are reported in Table.

GENERAL INJURY RISK AND PLAYING POSITION

Of the 11 studies included for qualitative synthesis, 5 studies reported no significant effect of player’s position on general risk of injury,^7-11 3 studies reported a greater risk in forwards,^12-14 1 study reported a greater risk in MFs,¹⁵ 1 study reported a greater risk in forwards and central defenders,⁸ and finally 1 study reported a significant lower risk in GKs.¹⁶ Additionally, 2 more studies reported GKs to be at the lowest injury risk,^12,13 another study reported GKs to have lost the lower number of matches,⁸ 1 study didn’t consider the GK position in the analysis due to the low number of injuries,¹⁷ limiting the analysis on the outfield positions.

Out of the 5 studies reporting no significant effect of playing position on injury risk, 1 study found a tendency to more injuries in forward players,¹⁰ a second study found a tendency for higher injury risk in midfielders,¹⁸ and a third study found a tendency for higher risk in defenders.¹⁷ Considering only the 5 studies reporting data on match injuries, 3 reported a higher risk in forwards,^12-14 while a fourth one reported a tendency for increased risk in forwards¹⁰ even if not statistically significant. On the other hand, evaluating the 6 studies reporting data on match and training injuries, most of the studies, 4 out of 6, reported no effect of playing position.^17-20 The main findings of the studies are also expressed graphically in Figures 2A, 2B.

DISCUSSION

The main finding of this study is that there is substantially no agreement regarding the effect of player position on general injury risk in male soccer.

First, we must underline that not many studies have evaluated prospectively the influence of player’s position on injury risk. Of the 11 selected studies, 5 (5/11) reported no significant effect of playing position,^{7,10,17,18,20} while the remaining studies (6/11)^8,12-16 reported a significant effect of player position on the risk of injury, with various results depending on the single study. It should be noted that the 2 studies with the longest observational period (15 consecutive seasons)^16,19 did not report any difference in injury risk considering only the outfield playing positions.  

Continue to: We will now review the findings...

 

 

We will now review the findings of our systematic review based on player position. One of the more consistent trends that we found is the possible occurrence of different injury epidemiology in GKs compared to outfield players. One study reported a significant lower incidence of match injuries for GKs, 12.9 injuries per 1000 game hours vs 22.6 injuries per 1000 game hours of outfield positions.¹⁶ This result is remarkable, even considering the very long observational period (15 seasons). Other 2 studies, not reporting position specific injury incidence (but proportion of injuries) also agreed on the topic.^12,13 On the other hand, Morgan and Oberlander⁹ reported no differences between GKs and other positions. Anecdotally, unpublished Major League Soccer data regarding the most recent seasons seems to support these findings with GKs sustaining the lower proportion of injuries. By a physiological point of view, somatotype and body composition have been reported to differ between GKs and the other playing positions in young male soccer players.²¹ The uniqueness of the GK somatotype and role may reflect on a predisposition to a different pattern of injuries. Ekstrand and colleagues²² reported that GKs have a higher incidence of upper extremity fractures, the same group demonstrated a possible tendency for more head and neck injuries⁹ and a lower risk of medial collateral ligament injuries.²³ On the other hand, GKs seems to be at lower injury risk for the playing pattern differences with outfield players. The reduced distance GKs cover during the match, as well as less direct contacts with opponents, may be factors that potentially explain this finding.

In relation to forwards, 4 studies interestingly stated that forwards were at increased risk of injury,^12-14 although 1 report had similar risk of injury with forwards and defenders.⁸ Most of the studies only on match injuries reported some association between forward position and injury risk (Figures 2A, 2B), so attackers may be at higher risk of match injuries when compared to the other playing positions. There are different possible explanations for this finding. First, it is demonstrated that the clear majority of soccer incidents happen in the mid-defensive zone and in the score-box,²⁴ 2 typical attackers’ zones, where most of duels and tackles may happen. So, forwards may be more prone to match injuries because of the intensity of match play in their typical playing zones. Also, fast kicking and acceleration/deceleration activities of the attackers may predispose for thigh muscle injuries, accounting up to 25% of the total lay off time in professional soccer.²⁵ However, these considerations are still yet to be proven.

When considering defenders, 1 report indicated defenders (and forwards) to be at potential greater risk of injury,⁸which is similar to the report from Shalaj and colleagues,¹⁷ although it did not report a statistically significant result. A direct playing style, with defenders and strikers being more involved in the game can potentially explain this finding. However, the specific epidemiology of defenders may be more complicated. Defenders may be predisposed to knee injuries, such as injury to the anterior cruciate ligament (ACL). In fact, Walden and colleagues,¹¹ in a video-analysis study, reported that the 77% of ACL injuries happened in defending situations. In addition, Brophy and colleagues,⁶ in another video-analysis study, reported a 73% of ACL injuries happened while defending. A likely explanation is the nature of the defender’s role in soccer, reactive to the attacking team actions. Many times, defenders try high risk maneuvers while tackling the opponent, with minimal motor planning time and consciousness. This is well described by Walden and colleagues,¹¹ with the pressing mechanism ACL injury, when the injured player is pressing the opponent in the attempt to get the ball but eventually falls into a high-risk position.

When considering MFs, Deehan and colleagues¹⁵ found a significant higher risk in MFs in youth soccer. This result is partially according to Morgan and Oberlander¹⁸ who reported a non-statistically significant greater injury incidence in MFs. MFs are generally the players that cover more distance during a soccer match and it is logical to think that they would be predisposed to a large volume of acceleration/deceleration activities,¹⁹ potentially relating to injury risk, especially to muscles injuries. A previous study on thigh muscle injuries in youth soccer reporting higher injury risk in MFs, followed by forwards.¹⁹ Consistent with these results, another study on a mixed male and female cohort on high school soccer revealed more injuries in MFs, followed by forwards^.26

Continue to: The results of this systematic review...

 

 

The results of this systematic review reveal mixed reports on injury risk in relation to playing position, the more consistent results through studies was that GKs may be at lower injury risk compared to the outfield players, even if there wasn’t complete agreement. One should note that in modern soccer the specific role of any player at 1 position may not be entirely consistent with another player in the same position. Within the same “position group”, there may also be players with completely different qualitative playing demands (eg, wing defender and central defender). So, even with the strongest study design, it may be difficult to give a simple and clear message about playing position and injury risk due to the variability of the playing styles and players at each position.

This study has several limitations and the results must be considered and interpreted with caution. First, we limited our search to male soccer, so the results may not be applicable to female soccer. Secondly, the interpretation of study findings wasn’t easy because of the different report modalities of the different papers included in the systematic review. Finally, we included reports from a total of a 23-year time span and from different countries and continents. The game may have evolved through years and there may be differences in the style of playing within countries that potentially could interfere with injury risk.

However, this is the first paper systematically evaluating the existing literature on position specific injury risk in male soccer players. Future studies, with prospective design and a consistent method to evaluate the player position as a potential factor related to injury risk, are needed. Match and training injuries should be evaluated separately as playing position may be more related to match injury risk.

CONCLUSION

There is no agreement in the existing literature regarding weather or not player position influence the general injury risk in male soccer. The GKs may have a lower risk of injury if compared to outfield players.

ABSTRACT

Soccer (football) is a complex contact sport with a substantial risk of injury. As injury surveillance is the first step of the injury prevention paradigm, soccer epidemiology is well reported in the existing literature, but less is known about the actual role of player position on the general injury risk.

The goal of this study is to present the existing evidence regarding the influence of player’s position on general injury risk in male soccer.

A systematic review of the Medline database was carried out. Only English written studies on male soccer and citing playing position as a possible determinant of injury risk were included. One hundred and two full texts were evaluated for eligibility, and 11 studies were selected for the qualitative synthesis.

Of the 11 studies included in the systematic review, 5 didn’t find any significant correlation with between player’s position and general injury risk, while the remaining 6 studies found player’s position to be correlated with injury risk, with mixed findings depending on each study. The most consistent finding was a tendency for goalkeepers (GKs) to sustain less injuries compared to outfield players. When considering only the studies reporting just the match injury risk, forwards seemed to be at higher risk, even if there wasn’t a complete agreement.

Few studies have evaluated a possible effect of playing position on general injury risk in male soccer. There is no agreement if weather or not different playing positions are associated to a higher injury risk. GKs seem to be at lower risk of injury when compared to outfield players.

Continue to: Soccer, known worldwide as football, is the most...

Soccer, known worldwide as football, is the most common practiced sport worldwide. Soccer is also a complex contact sport with a substantial injury risk,¹ that is well documented in the current literature. According to a recent systematic review, general injury incidence in male soccer ranged from 2.0 injuries to 19.4 injuries per 1000 hours of exposure in youth male soccer and from 2.48 injuries to 9.4 injuries per 1000 hours of exposure in elite male soccer.¹ It is also well established that the injury risk is greater in matches than training.¹ Soccer’s injuries are well known to be a socioeconomic burden for elite, youth, and recreational players.² Different authors have underlined the problem that nowadays the game is faster, and players need to have a better physical performance as they are subjected to important efforts both metabolically and biomechanically during match play. In the last decades, thanks to different research groups involved with professional soccer,³ there has been an increasing interest in soccer injuries’ epidemiology and for preventative measures.⁴ A deep comprehension of injury epidemiology is in fact the first necessary step for successful preventative measures. Regarding a possible correlation between playing position and injury incidence, there is a lack of consensus in the literature. Player position (goalkeeper [GK], defenders, midfielder [MF], or striker) may affect injury risk, as different roles are associated to different intensity during match play⁵ and experience different combination of anticipated or non-anticipated movement patterns.⁶ Previous authors underlined that few studies have evaluated a possible influence of playing position on injury incidence and severity.⁷

The main goal of this systematic review is to present the existing evidence regarding the influence of player position on injury incidence in male soccer and to present practical considerations on each field position in relation to the injury’s risk.

METHODS

DATA SOURCES AND SELECTION CRITERIA

We searched the Medline database for key terms and their variations to identify appropriate studies on injury epidemiology in soccer and specific player position influence. The keywords included: injury epidemiology soccer [OR] injury epidemiology football; position specific injury epidemiology soccer [OR] football. We limited our search to originally published English-language research articles.

Relevant data were extracted for study characteristics to ensure the included studies met certain criteria. The inclusion criteria were prospective design with minimum 6-month observational period, exclusively male soccer players’ cohorts, reported injury incidence, and documented player position in correlation with a measure of injury risk.

As stated above, we only included studies on male soccer. We also did not consider studies limited to a single injury type, considering only studies analyzing and documenting all injuries. We did not exclude studies on youth soccer but we didn’t consider studies on ≥2 more sports or mixed male and female studies.

Data were extracted by an author (FDV) and qualitatively controlled by another one (BM). Controversy were solved through discussion or confrontation with another author (LL).

Results of the included studies are presented only qualitatively because of different methodologies we encountered in documenting the potential effects of player’s role. Some studies reported differences in injury incidence within groups, others reported the proportion of injuries for each subgroup.  

Continue to: RESULTS...

 

 

RESULTS

STUDY SELECTION

Of the 1609 potential items we found in the existing literature, 102 full-text articles were screened for eligibility. Only 11 papers met the inclusion criteria and were included in the systematic review, including 2 studies on youth soccer and 9 studies on adult soccer (Figure 1). Five of the selected studies tracked only match injuries, while the remaining 6 studies presented data on both match and training injuries. As a matter of fact, the effect of player position was not so commonly evaluated or at least reported in the existing literature. Studies’ characteristics and main findings regarding player’s position are reported in Table.

GENERAL INJURY RISK AND PLAYING POSITION

Of the 11 studies included for qualitative synthesis, 5 studies reported no significant effect of player’s position on general risk of injury,^7-11 3 studies reported a greater risk in forwards,^12-14 1 study reported a greater risk in MFs,¹⁵ 1 study reported a greater risk in forwards and central defenders,⁸ and finally 1 study reported a significant lower risk in GKs.¹⁶ Additionally, 2 more studies reported GKs to be at the lowest injury risk,^12,13 another study reported GKs to have lost the lower number of matches,⁸ 1 study didn’t consider the GK position in the analysis due to the low number of injuries,¹⁷ limiting the analysis on the outfield positions.

Out of the 5 studies reporting no significant effect of playing position on injury risk, 1 study found a tendency to more injuries in forward players,¹⁰ a second study found a tendency for higher injury risk in midfielders,¹⁸ and a third study found a tendency for higher risk in defenders.¹⁷ Considering only the 5 studies reporting data on match injuries, 3 reported a higher risk in forwards,^12-14 while a fourth one reported a tendency for increased risk in forwards¹⁰ even if not statistically significant. On the other hand, evaluating the 6 studies reporting data on match and training injuries, most of the studies, 4 out of 6, reported no effect of playing position.^17-20 The main findings of the studies are also expressed graphically in Figures 2A, 2B.

DISCUSSION

The main finding of this study is that there is substantially no agreement regarding the effect of player position on general injury risk in male soccer.

First, we must underline that not many studies have evaluated prospectively the influence of player’s position on injury risk. Of the 11 selected studies, 5 (5/11) reported no significant effect of playing position,^{7,10,17,18,20} while the remaining studies (6/11)^8,12-16 reported a significant effect of player position on the risk of injury, with various results depending on the single study. It should be noted that the 2 studies with the longest observational period (15 consecutive seasons)^16,19 did not report any difference in injury risk considering only the outfield playing positions.  

Continue to: We will now review the findings...

 

 

We will now review the findings of our systematic review based on player position. One of the more consistent trends that we found is the possible occurrence of different injury epidemiology in GKs compared to outfield players. One study reported a significant lower incidence of match injuries for GKs, 12.9 injuries per 1000 game hours vs 22.6 injuries per 1000 game hours of outfield positions.¹⁶ This result is remarkable, even considering the very long observational period (15 seasons). Other 2 studies, not reporting position specific injury incidence (but proportion of injuries) also agreed on the topic.^12,13 On the other hand, Morgan and Oberlander⁹ reported no differences between GKs and other positions. Anecdotally, unpublished Major League Soccer data regarding the most recent seasons seems to support these findings with GKs sustaining the lower proportion of injuries. By a physiological point of view, somatotype and body composition have been reported to differ between GKs and the other playing positions in young male soccer players.²¹ The uniqueness of the GK somatotype and role may reflect on a predisposition to a different pattern of injuries. Ekstrand and colleagues²² reported that GKs have a higher incidence of upper extremity fractures, the same group demonstrated a possible tendency for more head and neck injuries⁹ and a lower risk of medial collateral ligament injuries.²³ On the other hand, GKs seems to be at lower injury risk for the playing pattern differences with outfield players. The reduced distance GKs cover during the match, as well as less direct contacts with opponents, may be factors that potentially explain this finding.

In relation to forwards, 4 studies interestingly stated that forwards were at increased risk of injury,^12-14 although 1 report had similar risk of injury with forwards and defenders.⁸ Most of the studies only on match injuries reported some association between forward position and injury risk (Figures 2A, 2B), so attackers may be at higher risk of match injuries when compared to the other playing positions. There are different possible explanations for this finding. First, it is demonstrated that the clear majority of soccer incidents happen in the mid-defensive zone and in the score-box,²⁴ 2 typical attackers’ zones, where most of duels and tackles may happen. So, forwards may be more prone to match injuries because of the intensity of match play in their typical playing zones. Also, fast kicking and acceleration/deceleration activities of the attackers may predispose for thigh muscle injuries, accounting up to 25% of the total lay off time in professional soccer.²⁵ However, these considerations are still yet to be proven.

When considering defenders, 1 report indicated defenders (and forwards) to be at potential greater risk of injury,⁸which is similar to the report from Shalaj and colleagues,¹⁷ although it did not report a statistically significant result. A direct playing style, with defenders and strikers being more involved in the game can potentially explain this finding. However, the specific epidemiology of defenders may be more complicated. Defenders may be predisposed to knee injuries, such as injury to the anterior cruciate ligament (ACL). In fact, Walden and colleagues,¹¹ in a video-analysis study, reported that the 77% of ACL injuries happened in defending situations. In addition, Brophy and colleagues,⁶ in another video-analysis study, reported a 73% of ACL injuries happened while defending. A likely explanation is the nature of the defender’s role in soccer, reactive to the attacking team actions. Many times, defenders try high risk maneuvers while tackling the opponent, with minimal motor planning time and consciousness. This is well described by Walden and colleagues,¹¹ with the pressing mechanism ACL injury, when the injured player is pressing the opponent in the attempt to get the ball but eventually falls into a high-risk position.

When considering MFs, Deehan and colleagues¹⁵ found a significant higher risk in MFs in youth soccer. This result is partially according to Morgan and Oberlander¹⁸ who reported a non-statistically significant greater injury incidence in MFs. MFs are generally the players that cover more distance during a soccer match and it is logical to think that they would be predisposed to a large volume of acceleration/deceleration activities,¹⁹ potentially relating to injury risk, especially to muscles injuries. A previous study on thigh muscle injuries in youth soccer reporting higher injury risk in MFs, followed by forwards.¹⁹ Consistent with these results, another study on a mixed male and female cohort on high school soccer revealed more injuries in MFs, followed by forwards^.26

Continue to: The results of this systematic review...

 

 

The results of this systematic review reveal mixed reports on injury risk in relation to playing position, the more consistent results through studies was that GKs may be at lower injury risk compared to the outfield players, even if there wasn’t complete agreement. One should note that in modern soccer the specific role of any player at 1 position may not be entirely consistent with another player in the same position. Within the same “position group”, there may also be players with completely different qualitative playing demands (eg, wing defender and central defender). So, even with the strongest study design, it may be difficult to give a simple and clear message about playing position and injury risk due to the variability of the playing styles and players at each position.

This study has several limitations and the results must be considered and interpreted with caution. First, we limited our search to male soccer, so the results may not be applicable to female soccer. Secondly, the interpretation of study findings wasn’t easy because of the different report modalities of the different papers included in the systematic review. Finally, we included reports from a total of a 23-year time span and from different countries and continents. The game may have evolved through years and there may be differences in the style of playing within countries that potentially could interfere with injury risk.

However, this is the first paper systematically evaluating the existing literature on position specific injury risk in male soccer players. Future studies, with prospective design and a consistent method to evaluate the player position as a potential factor related to injury risk, are needed. Match and training injuries should be evaluated separately as playing position may be more related to match injury risk.

CONCLUSION

There is no agreement in the existing literature regarding weather or not player position influence the general injury risk in male soccer. The GKs may have a lower risk of injury if compared to outfield players.

ABSTRACT

Soccer (football) is a complex contact sport with a substantial risk of injury. As injury surveillance is the first step of the injury prevention paradigm, soccer epidemiology is well reported in the existing literature, but less is known about the actual role of player position on the general injury risk.

The goal of this study is to present the existing evidence regarding the influence of player’s position on general injury risk in male soccer.

A systematic review of the Medline database was carried out. Only English written studies on male soccer and citing playing position as a possible determinant of injury risk were included. One hundred and two full texts were evaluated for eligibility, and 11 studies were selected for the qualitative synthesis.

Of the 11 studies included in the systematic review, 5 didn’t find any significant correlation with between player’s position and general injury risk, while the remaining 6 studies found player’s position to be correlated with injury risk, with mixed findings depending on each study. The most consistent finding was a tendency for goalkeepers (GKs) to sustain less injuries compared to outfield players. When considering only the studies reporting just the match injury risk, forwards seemed to be at higher risk, even if there wasn’t a complete agreement.

Few studies have evaluated a possible effect of playing position on general injury risk in male soccer. There is no agreement if weather or not different playing positions are associated to a higher injury risk. GKs seem to be at lower risk of injury when compared to outfield players.

Continue to: Soccer, known worldwide as football, is the most...

Soccer, known worldwide as football, is the most common practiced sport worldwide. Soccer is also a complex contact sport with a substantial injury risk,¹ that is well documented in the current literature. According to a recent systematic review, general injury incidence in male soccer ranged from 2.0 injuries to 19.4 injuries per 1000 hours of exposure in youth male soccer and from 2.48 injuries to 9.4 injuries per 1000 hours of exposure in elite male soccer.¹ It is also well established that the injury risk is greater in matches than training.¹ Soccer’s injuries are well known to be a socioeconomic burden for elite, youth, and recreational players.² Different authors have underlined the problem that nowadays the game is faster, and players need to have a better physical performance as they are subjected to important efforts both metabolically and biomechanically during match play. In the last decades, thanks to different research groups involved with professional soccer,³ there has been an increasing interest in soccer injuries’ epidemiology and for preventative measures.⁴ A deep comprehension of injury epidemiology is in fact the first necessary step for successful preventative measures. Regarding a possible correlation between playing position and injury incidence, there is a lack of consensus in the literature. Player position (goalkeeper [GK], defenders, midfielder [MF], or striker) may affect injury risk, as different roles are associated to different intensity during match play⁵ and experience different combination of anticipated or non-anticipated movement patterns.⁶ Previous authors underlined that few studies have evaluated a possible influence of playing position on injury incidence and severity.⁷

The main goal of this systematic review is to present the existing evidence regarding the influence of player position on injury incidence in male soccer and to present practical considerations on each field position in relation to the injury’s risk.

METHODS

DATA SOURCES AND SELECTION CRITERIA

We searched the Medline database for key terms and their variations to identify appropriate studies on injury epidemiology in soccer and specific player position influence. The keywords included: injury epidemiology soccer [OR] injury epidemiology football; position specific injury epidemiology soccer [OR] football. We limited our search to originally published English-language research articles.

Relevant data were extracted for study characteristics to ensure the included studies met certain criteria. The inclusion criteria were prospective design with minimum 6-month observational period, exclusively male soccer players’ cohorts, reported injury incidence, and documented player position in correlation with a measure of injury risk.

As stated above, we only included studies on male soccer. We also did not consider studies limited to a single injury type, considering only studies analyzing and documenting all injuries. We did not exclude studies on youth soccer but we didn’t consider studies on ≥2 more sports or mixed male and female studies.

Data were extracted by an author (FDV) and qualitatively controlled by another one (BM). Controversy were solved through discussion or confrontation with another author (LL).

Results of the included studies are presented only qualitatively because of different methodologies we encountered in documenting the potential effects of player’s role. Some studies reported differences in injury incidence within groups, others reported the proportion of injuries for each subgroup.  

Continue to: RESULTS...

 

 

RESULTS

STUDY SELECTION

Of the 1609 potential items we found in the existing literature, 102 full-text articles were screened for eligibility. Only 11 papers met the inclusion criteria and were included in the systematic review, including 2 studies on youth soccer and 9 studies on adult soccer (Figure 1). Five of the selected studies tracked only match injuries, while the remaining 6 studies presented data on both match and training injuries. As a matter of fact, the effect of player position was not so commonly evaluated or at least reported in the existing literature. Studies’ characteristics and main findings regarding player’s position are reported in Table.

GENERAL INJURY RISK AND PLAYING POSITION

Of the 11 studies included for qualitative synthesis, 5 studies reported no significant effect of player’s position on general risk of injury,^7-11 3 studies reported a greater risk in forwards,^12-14 1 study reported a greater risk in MFs,¹⁵ 1 study reported a greater risk in forwards and central defenders,⁸ and finally 1 study reported a significant lower risk in GKs.¹⁶ Additionally, 2 more studies reported GKs to be at the lowest injury risk,^12,13 another study reported GKs to have lost the lower number of matches,⁸ 1 study didn’t consider the GK position in the analysis due to the low number of injuries,¹⁷ limiting the analysis on the outfield positions.

Out of the 5 studies reporting no significant effect of playing position on injury risk, 1 study found a tendency to more injuries in forward players,¹⁰ a second study found a tendency for higher injury risk in midfielders,¹⁸ and a third study found a tendency for higher risk in defenders.¹⁷ Considering only the 5 studies reporting data on match injuries, 3 reported a higher risk in forwards,^12-14 while a fourth one reported a tendency for increased risk in forwards¹⁰ even if not statistically significant. On the other hand, evaluating the 6 studies reporting data on match and training injuries, most of the studies, 4 out of 6, reported no effect of playing position.^17-20 The main findings of the studies are also expressed graphically in Figures 2A, 2B.

DISCUSSION

The main finding of this study is that there is substantially no agreement regarding the effect of player position on general injury risk in male soccer.

First, we must underline that not many studies have evaluated prospectively the influence of player’s position on injury risk. Of the 11 selected studies, 5 (5/11) reported no significant effect of playing position,^{7,10,17,18,20} while the remaining studies (6/11)^8,12-16 reported a significant effect of player position on the risk of injury, with various results depending on the single study. It should be noted that the 2 studies with the longest observational period (15 consecutive seasons)^16,19 did not report any difference in injury risk considering only the outfield playing positions.  

Continue to: We will now review the findings...

 

 

We will now review the findings of our systematic review based on player position. One of the more consistent trends that we found is the possible occurrence of different injury epidemiology in GKs compared to outfield players. One study reported a significant lower incidence of match injuries for GKs, 12.9 injuries per 1000 game hours vs 22.6 injuries per 1000 game hours of outfield positions.¹⁶ This result is remarkable, even considering the very long observational period (15 seasons). Other 2 studies, not reporting position specific injury incidence (but proportion of injuries) also agreed on the topic.^12,13 On the other hand, Morgan and Oberlander⁹ reported no differences between GKs and other positions. Anecdotally, unpublished Major League Soccer data regarding the most recent seasons seems to support these findings with GKs sustaining the lower proportion of injuries. By a physiological point of view, somatotype and body composition have been reported to differ between GKs and the other playing positions in young male soccer players.²¹ The uniqueness of the GK somatotype and role may reflect on a predisposition to a different pattern of injuries. Ekstrand and colleagues²² reported that GKs have a higher incidence of upper extremity fractures, the same group demonstrated a possible tendency for more head and neck injuries⁹ and a lower risk of medial collateral ligament injuries.²³ On the other hand, GKs seems to be at lower injury risk for the playing pattern differences with outfield players. The reduced distance GKs cover during the match, as well as less direct contacts with opponents, may be factors that potentially explain this finding.

In relation to forwards, 4 studies interestingly stated that forwards were at increased risk of injury,^12-14 although 1 report had similar risk of injury with forwards and defenders.⁸ Most of the studies only on match injuries reported some association between forward position and injury risk (Figures 2A, 2B), so attackers may be at higher risk of match injuries when compared to the other playing positions. There are different possible explanations for this finding. First, it is demonstrated that the clear majority of soccer incidents happen in the mid-defensive zone and in the score-box,²⁴ 2 typical attackers’ zones, where most of duels and tackles may happen. So, forwards may be more prone to match injuries because of the intensity of match play in their typical playing zones. Also, fast kicking and acceleration/deceleration activities of the attackers may predispose for thigh muscle injuries, accounting up to 25% of the total lay off time in professional soccer.²⁵ However, these considerations are still yet to be proven.

When considering defenders, 1 report indicated defenders (and forwards) to be at potential greater risk of injury,⁸which is similar to the report from Shalaj and colleagues,¹⁷ although it did not report a statistically significant result. A direct playing style, with defenders and strikers being more involved in the game can potentially explain this finding. However, the specific epidemiology of defenders may be more complicated. Defenders may be predisposed to knee injuries, such as injury to the anterior cruciate ligament (ACL). In fact, Walden and colleagues,¹¹ in a video-analysis study, reported that the 77% of ACL injuries happened in defending situations. In addition, Brophy and colleagues,⁶ in another video-analysis study, reported a 73% of ACL injuries happened while defending. A likely explanation is the nature of the defender’s role in soccer, reactive to the attacking team actions. Many times, defenders try high risk maneuvers while tackling the opponent, with minimal motor planning time and consciousness. This is well described by Walden and colleagues,¹¹ with the pressing mechanism ACL injury, when the injured player is pressing the opponent in the attempt to get the ball but eventually falls into a high-risk position.

When considering MFs, Deehan and colleagues¹⁵ found a significant higher risk in MFs in youth soccer. This result is partially according to Morgan and Oberlander¹⁸ who reported a non-statistically significant greater injury incidence in MFs. MFs are generally the players that cover more distance during a soccer match and it is logical to think that they would be predisposed to a large volume of acceleration/deceleration activities,¹⁹ potentially relating to injury risk, especially to muscles injuries. A previous study on thigh muscle injuries in youth soccer reporting higher injury risk in MFs, followed by forwards.¹⁹ Consistent with these results, another study on a mixed male and female cohort on high school soccer revealed more injuries in MFs, followed by forwards^.26

Continue to: The results of this systematic review...

 

 

The results of this systematic review reveal mixed reports on injury risk in relation to playing position, the more consistent results through studies was that GKs may be at lower injury risk compared to the outfield players, even if there wasn’t complete agreement. One should note that in modern soccer the specific role of any player at 1 position may not be entirely consistent with another player in the same position. Within the same “position group”, there may also be players with completely different qualitative playing demands (eg, wing defender and central defender). So, even with the strongest study design, it may be difficult to give a simple and clear message about playing position and injury risk due to the variability of the playing styles and players at each position.

This study has several limitations and the results must be considered and interpreted with caution. First, we limited our search to male soccer, so the results may not be applicable to female soccer. Secondly, the interpretation of study findings wasn’t easy because of the different report modalities of the different papers included in the systematic review. Finally, we included reports from a total of a 23-year time span and from different countries and continents. The game may have evolved through years and there may be differences in the style of playing within countries that potentially could interfere with injury risk.

However, this is the first paper systematically evaluating the existing literature on position specific injury risk in male soccer players. Future studies, with prospective design and a consistent method to evaluate the player position as a potential factor related to injury risk, are needed. Match and training injuries should be evaluated separately as playing position may be more related to match injury risk.

CONCLUSION

There is no agreement in the existing literature regarding weather or not player position influence the general injury risk in male soccer. The GKs may have a lower risk of injury if compared to outfield players.

ABSTRACT

Upper limb injuries in soccer represent only a marginal portion of injuries, however this is mainly true for outfield players. Goalkeepers are reported to have up to 5 times more upper extremity injuries, many of them requiring substantial time-loss for treatment and rehabilitation. The most common upper extremity injury locations are the shoulder/clavicle followed by the hand/finger/thumb, elbow, wrist, forearm, and upper arm. The mechanism of injury, presentation, physical examination, and imaging features all play a significant role in reaching the correct diagnosis. Taking to consideration the position the player plays and his demands will also enable tailoring the optimal treatment plan that allows timely and safe return to play. This article discusses common upper extremity injuries observed in soccer players, focusing on proper diagnosis and optimal management.

Continue to: Upper limb injuries in association with soccer...

Upper limb injuries in association with soccer have been reported to represent only 3% of all time-loss injuries in professional soccer players¹. However, they are considered an increasing problem in recent years^2-4 and have been reported in high proportions in children under the age of 15 years.⁵ Some of the reasons for the increase in upper extremity injuries may be explained by modern soccer tactics that have been characterized by high speed, pressing, and marking.² Furthermore, upper extremity injuries may still be underestimated in soccer, mainly because outfield players are sometimes able to train and play even when they suffer from an upper extremity injury.

ABSTRACT

Upper limb injuries in soccer represent only a marginal portion of injuries, however this is mainly true for outfield players. Goalkeepers are reported to have up to 5 times more upper extremity injuries, many of them requiring substantial time-loss for treatment and rehabilitation. The most common upper extremity injury locations are the shoulder/clavicle followed by the hand/finger/thumb, elbow, wrist, forearm, and upper arm. The mechanism of injury, presentation, physical examination, and imaging features all play a significant role in reaching the correct diagnosis. Taking to consideration the position the player plays and his demands will also enable tailoring the optimal treatment plan that allows timely and safe return to play. This article discusses common upper extremity injuries observed in soccer players, focusing on proper diagnosis and optimal management.

Continue to: Upper limb injuries in association with soccer...

Upper limb injuries in association with soccer have been reported to represent only 3% of all time-loss injuries in professional soccer players¹. However, they are considered an increasing problem in recent years^2-4 and have been reported in high proportions in children under the age of 15 years.⁵ Some of the reasons for the increase in upper extremity injuries may be explained by modern soccer tactics that have been characterized by high speed, pressing, and marking.² Furthermore, upper extremity injuries may still be underestimated in soccer, mainly because outfield players are sometimes able to train and play even when they suffer from an upper extremity injury.

ABSTRACT

Upper limb injuries in soccer represent only a marginal portion of injuries, however this is mainly true for outfield players. Goalkeepers are reported to have up to 5 times more upper extremity injuries, many of them requiring substantial time-loss for treatment and rehabilitation. The most common upper extremity injury locations are the shoulder/clavicle followed by the hand/finger/thumb, elbow, wrist, forearm, and upper arm. The mechanism of injury, presentation, physical examination, and imaging features all play a significant role in reaching the correct diagnosis. Taking to consideration the position the player plays and his demands will also enable tailoring the optimal treatment plan that allows timely and safe return to play. This article discusses common upper extremity injuries observed in soccer players, focusing on proper diagnosis and optimal management.

Continue to: Upper limb injuries in association with soccer...

Upper limb injuries in association with soccer have been reported to represent only 3% of all time-loss injuries in professional soccer players¹. However, they are considered an increasing problem in recent years^2-4 and have been reported in high proportions in children under the age of 15 years.⁵ Some of the reasons for the increase in upper extremity injuries may be explained by modern soccer tactics that have been characterized by high speed, pressing, and marking.² Furthermore, upper extremity injuries may still be underestimated in soccer, mainly because outfield players are sometimes able to train and play even when they suffer from an upper extremity injury.

Any given weekend where the sun is shining in the United States, you can jump in your car and see children competing on the soccer field. Soccer, known as football in other countries, is one of the most played sports in the US with over 25 million children participating every year. Despite Americans’ mass participation in youth soccer, this level of enthusiasm hasn’t necessarily translated into soccer being one of our most watched sports. On an international level, soccer is not only a sport but a way of life, and it is often described as “the beautiful game”, as visions of Pelé, Kaká, Messi, Ronaldo, and others can invoke emotional responses in the hearts of so many people across the world.

Over the course of the past 20 years, the enthusiasm for soccer in the US has grown significantly as defined not only by the number of youth players on the field but also now by the increased number of professional teams, energetic supporters in the stands, and fans watching on their televisions at home. This exponential growth started with the success of our US Soccer National Teams in the 1990s, including the 1994 World Cup held in the US, and became cemented into the culture of American sports with the birth, development, and subsequent growth of Major League Soccer (MLS) across the country. Despite the recent disappointment of the US Men’s National Team not making the 2018 World Cup, Americans should remain excited that our US Women’s National Team is prepared to be a contender in the 2019 World Cup, our US Men’s National Team will certainly make a significant push to compete in the 2022 World Cup, and the US is again ready to re-energize Americans’ interest in soccer by hosting a collaborative bid for the Men’s 2026 World Cup!

Now that I have hopefully energized all of our readers about the current and future impact of soccer within the US, I am personally excited about being an active member of the soccer medicine community through my roles as the Chief Medical Officer of the Orlando City Soccer Club, including Orlando City Lions MLS team and Orlando Pride National Women’s Soccer League (NWSL) team, and a Team Physician for US Soccer. What most people don’t realize in the sports medicine community and beyond is that our MLS and US soccer medical teams have been working tirelessly for the last 20 years to not only provide top-notch medical care within our country but to create one of the best medical structures in the world.

Over the last several years, I have learned that our soccer medical community is fortunate to have strength in numbers. In fact, our international colleagues provide a collaborative team to help push the limits on medical innovation so that we constantly reflect upon the quality of care that we are providing for the ultimate improvement of the medical care for all of our players. I recently returned from a trip to Barcelona for the Isokinetic Medical Group Football, known as soccer in the US, Medicine Outcomes Meeting where over 3000 participants from almost 100 countries around the world attended. After previous involvement in Major League Baseball and the National Football League, and since my integration into the soccer medicine community several years ago, I have been amazed and challenged by the complexity of pathology that we see in soccer players and the attention to detail that is required to successfully transition a soccer player back to the field while also preventing a subsequent injury. In fact, soccer players require a unique combination of skill, fitness, performance, nutrition, and sustainability to be successful at the highest level of soccer. As a sports medicine community in the US, we have come so far but yet still have so much left to learn. I’m certainly excited that we will be able to build and share this knowledge base with not only my fellow Americans but also our international colleagues abroad. Who knows, after the 2026 World Cup, the further growth and solidification of soccer and soccer medicine in the US might enable me to change the title for my editorial with no resulting confusion: “Global Football Medicine for a Global Game”.

Any given weekend where the sun is shining in the United States, you can jump in your car and see children competing on the soccer field. Soccer, known as football in other countries, is one of the most played sports in the US with over 25 million children participating every year. Despite Americans’ mass participation in youth soccer, this level of enthusiasm hasn’t necessarily translated into soccer being one of our most watched sports. On an international level, soccer is not only a sport but a way of life, and it is often described as “the beautiful game”, as visions of Pelé, Kaká, Messi, Ronaldo, and others can invoke emotional responses in the hearts of so many people across the world.

Over the course of the past 20 years, the enthusiasm for soccer in the US has grown significantly as defined not only by the number of youth players on the field but also now by the increased number of professional teams, energetic supporters in the stands, and fans watching on their televisions at home. This exponential growth started with the success of our US Soccer National Teams in the 1990s, including the 1994 World Cup held in the US, and became cemented into the culture of American sports with the birth, development, and subsequent growth of Major League Soccer (MLS) across the country. Despite the recent disappointment of the US Men’s National Team not making the 2018 World Cup, Americans should remain excited that our US Women’s National Team is prepared to be a contender in the 2019 World Cup, our US Men’s National Team will certainly make a significant push to compete in the 2022 World Cup, and the US is again ready to re-energize Americans’ interest in soccer by hosting a collaborative bid for the Men’s 2026 World Cup!

Now that I have hopefully energized all of our readers about the current and future impact of soccer within the US, I am personally excited about being an active member of the soccer medicine community through my roles as the Chief Medical Officer of the Orlando City Soccer Club, including Orlando City Lions MLS team and Orlando Pride National Women’s Soccer League (NWSL) team, and a Team Physician for US Soccer. What most people don’t realize in the sports medicine community and beyond is that our MLS and US soccer medical teams have been working tirelessly for the last 20 years to not only provide top-notch medical care within our country but to create one of the best medical structures in the world.

Over the last several years, I have learned that our soccer medical community is fortunate to have strength in numbers. In fact, our international colleagues provide a collaborative team to help push the limits on medical innovation so that we constantly reflect upon the quality of care that we are providing for the ultimate improvement of the medical care for all of our players. I recently returned from a trip to Barcelona for the Isokinetic Medical Group Football, known as soccer in the US, Medicine Outcomes Meeting where over 3000 participants from almost 100 countries around the world attended. After previous involvement in Major League Baseball and the National Football League, and since my integration into the soccer medicine community several years ago, I have been amazed and challenged by the complexity of pathology that we see in soccer players and the attention to detail that is required to successfully transition a soccer player back to the field while also preventing a subsequent injury. In fact, soccer players require a unique combination of skill, fitness, performance, nutrition, and sustainability to be successful at the highest level of soccer. As a sports medicine community in the US, we have come so far but yet still have so much left to learn. I’m certainly excited that we will be able to build and share this knowledge base with not only my fellow Americans but also our international colleagues abroad. Who knows, after the 2026 World Cup, the further growth and solidification of soccer and soccer medicine in the US might enable me to change the title for my editorial with no resulting confusion: “Global Football Medicine for a Global Game”.

Any given weekend where the sun is shining in the United States, you can jump in your car and see children competing on the soccer field. Soccer, known as football in other countries, is one of the most played sports in the US with over 25 million children participating every year. Despite Americans’ mass participation in youth soccer, this level of enthusiasm hasn’t necessarily translated into soccer being one of our most watched sports. On an international level, soccer is not only a sport but a way of life, and it is often described as “the beautiful game”, as visions of Pelé, Kaká, Messi, Ronaldo, and others can invoke emotional responses in the hearts of so many people across the world.

Over the course of the past 20 years, the enthusiasm for soccer in the US has grown significantly as defined not only by the number of youth players on the field but also now by the increased number of professional teams, energetic supporters in the stands, and fans watching on their televisions at home. This exponential growth started with the success of our US Soccer National Teams in the 1990s, including the 1994 World Cup held in the US, and became cemented into the culture of American sports with the birth, development, and subsequent growth of Major League Soccer (MLS) across the country. Despite the recent disappointment of the US Men’s National Team not making the 2018 World Cup, Americans should remain excited that our US Women’s National Team is prepared to be a contender in the 2019 World Cup, our US Men’s National Team will certainly make a significant push to compete in the 2022 World Cup, and the US is again ready to re-energize Americans’ interest in soccer by hosting a collaborative bid for the Men’s 2026 World Cup!

Now that I have hopefully energized all of our readers about the current and future impact of soccer within the US, I am personally excited about being an active member of the soccer medicine community through my roles as the Chief Medical Officer of the Orlando City Soccer Club, including Orlando City Lions MLS team and Orlando Pride National Women’s Soccer League (NWSL) team, and a Team Physician for US Soccer. What most people don’t realize in the sports medicine community and beyond is that our MLS and US soccer medical teams have been working tirelessly for the last 20 years to not only provide top-notch medical care within our country but to create one of the best medical structures in the world.

Over the last several years, I have learned that our soccer medical community is fortunate to have strength in numbers. In fact, our international colleagues provide a collaborative team to help push the limits on medical innovation so that we constantly reflect upon the quality of care that we are providing for the ultimate improvement of the medical care for all of our players. I recently returned from a trip to Barcelona for the Isokinetic Medical Group Football, known as soccer in the US, Medicine Outcomes Meeting where over 3000 participants from almost 100 countries around the world attended. After previous involvement in Major League Baseball and the National Football League, and since my integration into the soccer medicine community several years ago, I have been amazed and challenged by the complexity of pathology that we see in soccer players and the attention to detail that is required to successfully transition a soccer player back to the field while also preventing a subsequent injury. In fact, soccer players require a unique combination of skill, fitness, performance, nutrition, and sustainability to be successful at the highest level of soccer. As a sports medicine community in the US, we have come so far but yet still have so much left to learn. I’m certainly excited that we will be able to build and share this knowledge base with not only my fellow Americans but also our international colleagues abroad. Who knows, after the 2026 World Cup, the further growth and solidification of soccer and soccer medicine in the US might enable me to change the title for my editorial with no resulting confusion: “Global Football Medicine for a Global Game”.

ABSTRACT

Soccer requires significant physical conditioning and endurance, as well as the physicality required for contact play. In order to keep athletes safe, it is important that coaches, medical staff, and the players themselves are educated on the most common dangers to their health that they may encounter on a soccer pitch. This article aims to review the current literature and recommendations on concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer, with a goal of educating all those who help to keep athletes healthy and competing to their full potential.  

Continue to: Soccer is one of the most popular sports...

Soccer is one of the most popular sports in the modern world and requires significant physical conditioning and endurance, as well as the physicality required for contact play. This article covers the topics of concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer players. We provide a review of the prevention, recognition, and management required to keep athletes safe on the soccer pitch, both in practice and in competitive play.

HEAD

With an estimated 1.6 to 3.8 million sports-related mild traumatic brain injuries (ie, concussions) occurring annually in the United States,¹ there has been an appropriate increase in the focus on prevention and treatment of these injuries. For more than a decade the spotlight has been on concussions that occur in American football, but other sports have also had to examine the prevalence of concussions in their sport. This is certainly true for soccer.

There has been a steady increase in soccer participation in the United States. From 1973 to 2014 there was a 4-fold increase in high school boys and a 35-fold increase in high school girls playing soccer.² Currently, there are more than 3.7 million youth who play on teams under the supervision of the US Soccer Federation, the sport’s national governing body.³ With the growth of the sport, there has also been an intensified focus on injury prevention in soccer players, including concussive brain injuries.

A recent study examined injury rates in high school soccer players and noted that concussion is the second most common injury (17.9%), after ligament sprains (29.7%).⁴ The overall injury rate was 2.06 per 1000 athletic exposures (AEs [defined as participation in practice or game play]), but higher in games (4.42 per 1000 AEs) than during practices (1.05 per 1000 AEs). The overall concussion rate was 0.36 per 1000 AEs.⁴

Most concussions (54.8%) resulted in missing play between 1 to 3 weeks, but a sizeable portion of the athletes (14.9%) were out of play for more than 3 weeks. Additionally, 10.7% of all medical disqualifications were due to concussive injuries. Khodaee and colleagues⁴ found no statistically significant difference in concussion rates between male and female soccer players over the 9-year period of time that they examined, however previous studies have found higher rates in female athletes.⁵

In soccer, as in other sports, there is a concern about both the adequate recognition of concussions during practice and play and the underreporting of concussions by athletes. The US Soccer Federation has taken a proactive stance on addressing concussion in youth soccer by developing the “Recognize to Recover” program.⁶ Recognize to Recover is the US Soccer Federation’s “comprehensive player health and safety program aimed at promoting safe play and reducing injuries in soccer players of all ages.” The website provides an educational video geared toward players, along with links to concussion assessment tools, the US Soccer Federation Concussion Protocol, and US Soccer Federation-Centers for Disease Control fact sheets for athletes, parents, and coaches.⁶

Continue to: A challenge for all sports...

 

 

A challenge for all sports is allowing adequate evaluation of a suspected concussion by properly trained healthcare professionals. The 2017 Berlin Concussion in Sport Group position paper stated, “when a concussion is suspected, the athlete should be removed from the sporting environment and a multimodal assessment should be conducted in standardized fashion (eg, Sport Concussion Assessment Tool- 5th edition). Sporting bodies should allow adequate time to conduct this evaluation.”⁷ However, the International Federation of Football Association (FIFA) rules limit substitutions to 3 over the course of the game, which can make a thorough evaluation of players difficult as trainers and coaches are under increased pressure to quickly determine whether to use one of their valuable substitutions. Fortunately, the National Collegiate Athletic Association (NCAA) soccer has mitigated this issue by allowing unlimited substitutions during matches, and high school teams generally follow similar rules.

One of the goals of any safety education program is not only to raise the awareness of the signs and symptoms of concussion by all those involved in the sport, but also to increase the number of athletes who self-report their symptoms and decrease those who hide any possible concussions. A study found that a majority (58.6%) of middle school soccer players continued to play while experiencing concussion symptoms.⁵ However, in a very recent (not yet published) study, 92% of US Soccer Federation players reported that they did seek out a medical evaluation for their concussion.⁸ This is certainly a positive sign and further research needs to clarify what methods of education or training will maintain this level of self-reporting in soccer players.

There has also been an increased focus on understanding the mechanism of injury of concussions. In soccer, concussions can occur from player-to-player contact, contact with the player surface, contact with playing apparatus (eg, goal posts) and non-contact mechanisms. While there has been a focus on concussions from heading the ball, player-to-player contact is the most common cause of concussions. A 2017 study of 7- to 12-year-old soccer players in 4 European countries found that about 1 out of 10 concussions were caused by heading the ball.⁹ Comstock and colleageues¹⁰ found slightly higher numbers, roughly 25% to 30% (depending on gender), but 70% to 78% (again depending on gender) of those were caused by player-to-player contact rather than contact with the ball.

To date there has not been any meta-analytic review evaluating the cognitive and physical symptoms associated with heading in soccer. A recent review paper stated that the “current evidence seems insufficient to support a ban of heading in children’s football (soccer).”¹⁰ However, in December 2015 the US Soccer Federation included age-specific heading limitations. Players ages 10 years and under “shall not engage in heading, either in practices or in games” and players age 11 years and 12 years should have “limited heading in practice; maximum of 30 minutes of heading training per week, with no more than 15-20 headers per player, per week.”¹¹ US Soccer Federation officials acknowledged the limitations in the current science regarding heading in young soccer players but chose to err on the side of caution until further empirical evidence regarding the risks associated with repetitive heading is available.

The US Soccer Federation is also exploring other ways to reduce the incidence rate of concussions, including ensuring that the age-appropriate sized ball is used in practice and play, possible rule changes, evaluation of different playing surfaces, and equipment usage. To date, there is no strong evidence to support the use of mouth guards or helmets to reduce concussions in soccer. Additionally, the current data about the value of head impact sensors in soccer has not supported its widespread use.

Continue to: Finally, the issue of the prevalence...

 

 

Finally, the issue of the prevalence of chronic traumatic encephalopathy (CTE) in soccer players is beyond the scope of this article. The expert opinion from the 2017 US Soccer Federation, Major League Soccer (MLS), and National Women’s Soccer League (NWSL) conference concluded, “At present, no data exist that support that soccer participation is a risk factor for the development of neurodegenerative disease. Similarly, at this time, consistent with evidence discussed in the Berlin Concussion in Sport Group (CISG) Consensus Conference, our review suggests no causal relationship has been demonstrated between soccer and CTE pathology.”¹²

The more we know about concussions, both in general and those sustained during soccer play, the better we are able to diagnose and manage these injuries in our athletes. An important step is creating evidence-based protocols that evolve as our knowledge of concussions does as well. In April 2017, the US Soccer Federation, MLS, and the NWSL held a joint summit entitled, “Head Injury in Soccer: From Science to the Field” to address the current evidence-based science of concussions in soccer.⁸ An article discussing the findings of this meeting is forthcoming and will undoubtedly guide further development of concussion protocols for soccer players of all ages.

HEART

The physiologic demands of soccer place considerable stress on the cardiovascular system. Participation in training and competition is characterized by a combination of aerobic and anaerobic physiology with the typical athlete covering approximately 10 km over the course of the 90-minute match. The primary role of the heart and blood vessels is to supply the exercising skeletal muscle with oxygen and energy substrate and to clear the byproducts of metabolism. Among healthy athletes without cardiovascular disease, these processes are typically well tolerated and may be associated with beneficial cardiovascular adaptations over time. However, competitive soccer players are not completely immune to cardiovascular disease. Athletes across the age and competition spectrum may develop symptoms suggestive of underlying cardiovascular disease during play including exertional chest pain, inappropriate shortness of breath, palpitations, and syncope. These athletes require timely clinical evaluation. In extremely rare but high visibility cases, competitive soccer players may succumb to cardiac arrest on the pitch, underscoring the need for comprehensive emergency action plans (EAPs). We provide the practicing clinician with an overview of cardiovascular issues relevant to the competitive soccer athlete.

CARDIOVASCULAR ADAPTATIONS TO SPORT

The pressure (ie, repetitive surges in systemic blood pressure) and volume (ie, sustained increases in high cardiac output) challenges inherent in soccer participation place stress on the cardiovascular system. Healthy athletes across the age spectrum typically tolerate the hemodynamic stressors of participation without issues. Athletes that engage in training and competition over months to years often develop beneficial adaptations of the cardiovascular system that enhance on-field performance and contribute to optimal long-term health. Detailed discussion of how the heart and blood vessels respond to exercise training is beyond the scope of this article, but the interested reader is referred to several prior publications.^13,14 In brief, the heart of the healthy soccer athlete demonstrates the balanced mild chamber dilation and wall thickening characteristic of left ventricular eccentric remodeling. This form of exercise-induced cardiac remodeling facilitates maintenance of high stroke volume during exercise with minimal increases in cardiac work. In parallel, routine aerobic exercise training confers favorable changes in the systemic arterial system, which leads to reductions in age-associated ventricular stiffening and maintenance of healthy low blood pressure. It must be emphasized that the healthy heart muscle dilation and thickening that develop in response to sports participation, regardless of age, ethnicity, or gender, are relatively mild and should not be confused with common forms of heart muscle disease that may be seen in athletes at risk for adverse outcomes. In some situations, consultation with an extreme sports cardiologist may be required to differentiate exercise-induced remodeling from over heart muscle pathology.¹⁵

Continue to: THE SYMPTOMATIC ATHLETE...

 

 

THE SYMPTOMATIC ATHLETE

Any athlete presenting with symptoms suggestive of underlying cardiovascular disease should be withheld from training and competition until a comprehensive clinical evaluation has been completed. Common manifestations of underlying heart disease that occur in soccer players include exertional chest pain/pressure/tightness, shortness of breath that is out of proportion to workload, palpitations or the perception of irregular cardiac activity, and syncope. Chest discomfort, inappropriate shortness of breath, and palpitations that occur during training or competition should be managed with immediate removal from the playing field and prompt medical assessment. In many cases, thorough evaluation will involve collaboration between sports medicine and sports cardiology providers. Evaluations must be individualized on a case-by-case basis as tailored to the athlete’s presenting chief complaint and prior medical history. Most of these assessments will include a detailed medical history and physical examination, a 12-lead electrocardiogram (ECG), provocative exercise testing in a controlled environment, noninvasive cardiac imaging, and in some cases ambulatory rhythm monitoring. Uniformly, the athlete should be withheld from further training and competition until high-risk cardiovascular disease has been excluded. We refer the interested reader to a comprehensive discussion of symptom-based assessment of the athlete with suspected cardiovascular disease.¹⁶

Syncope (sudden and abrupt loss of consciousness with spontaneous neurologic recovery) is common among trained athletes. The vast majority of syncope is caused by “neurocardiogenic” mechanisms and carries a benign prognosis. Benign neurally-mediated syncope most often occurs outside of training and competition among athletes with heightened vagal tone and a predisposed susceptibility to triggers including pain, anxiety, emotional stimulation, and sudden postural change. Athletes who experience neurally-mediated syncope outside of training and competition routinely report a pre-event prodrome or aura that permits them to lower themselves to the ground, thereby avoiding injury. A distinct, but similarly benign and common, form of neurally-mediated fainting is post-exertional syncope. Here, fainting occurs within seconds of abrupt termination of exercise due to a rapid reduction cardiac preload and corollary cerebral blood supply. When either form of neurally-mediated syncope is suggested by a comprehensive medical history, normal physical examination, and a normal 12- lead ECG, further evaluation is unnecessary. However, the athlete and their coaching staff should be educated about avoidance tactics including hydration, dietary sodium supplementation, and avoidance of abrupt exercise termination as neutrally-mediated syncope tends to be recurrent without such measures. Fainting episodes that occur during training or competition that are not clearly post-exertional should be considered a medical emergency and should prompt comprehensive evaluation by a qualified cardiovascular specialist. Working closely with team physicians and athletic training staff, it is the responsibility of sports cardiologists to exclude potentially life-threatening forms of electrical, muscular, coronary, and valvular heart disease. Ideally, this evaluation should be conducted rapidly to avoid unnecessary delays in return to play.

CARDIAC ARREST AND SUDDEN DEATH

Numerous high-visibility cases of cardiac arrest on the soccer pitch have alerted the sporting community to the potential for these rare and potentially tragic events. Definitive incidence statistics defining the risk of cardiac arrest among soccer players are lacking. Data from the NCAA database suggest a sudden death incidence rate among collegiate male soccer athletes of approximately 1:24,000 athlete years.⁸ Similar data documenting incidence among female athletes and among those at lower (ie, youth level and high school) and higher (ie, professional) levels of play are unavailable. Underlying cardiovascular disease in the forms of heart muscle abnormalities (ie, genetic and acquired cardiomyopathy), coronary artery abnormalities (ie, genetic coronary anomalies and atherosclerotic coronary disease), valvular heart problems (ie, congenitally malformed aortic valves), and primary disturbances of the cardiac electrical system (ie, Wolf-Parkinson-White syndrome, long QT syndrome, etc.) explain a substantial percentage of on-pitch cardiac arrest. However, it is increasingly recognized that a significant minority of sudden cardiac deaths among athletes occur in the absence of attributable cardiovascular abnormality.¹⁷ Such cases, often referred to as “sudden unexplained death,” present unique challenges in the context of pre-participation screening, as they are undetectable and thus unpredictable.

Reduction of cardiac arrest and sudden death may best be accomplished through a combination of focused pre-participation screening and the development and implementation of a comprehensive EAP. Pre-participation involves the performance of a battery of tests prior to training and competition that are geared toward the detection of occult high-risk cardiovascular disease. Recommendations regarding pre-participation screening vary both across and within countries. Current US recommendations call for a focused medical history and physical examination prior to training and competition with consideration of the addition of a 12-lead ECG on a local level based on expertise and available resources.¹⁸ Conversely, current European guidelines including those endorsed by FIFA, suggest routine inclusion of a 12-lead ECG and in some cases, a transthoracic ECG.¹⁹ It must be emphasized that no screening approach has been confirmed to reduce the incidence of sudden death, and the decision to extend screening beyond the medical history and physical examination to include a 12-lead ECG or echocardiogram may come at the cost of increased false positive testing. In practice, decisions about how and when to screen are ideally made at a local level after consideration of medical and financial resources.²⁰

Continue to: Even the most comprehensive approach...

 

 

Even the most comprehensive approach to screening and evaluation of symptomatic athletes will not completely eliminate on-pitch cardiac arrest. Thus, all stakeholders that engage in the oversight of organized soccer must be committed to the development and implementation of an EAP.²¹ Key components of an effective EAP include the training of coaching staff, athletic trainers, and players in basic cardiopulmonary resuscitation, access to and training in the use of automated external defibrillators, and a triage/transport protocol that ensures timely access to advanced cardiac life support. Much like screening, emergency action planning involving these key core components must be developed and tailored locally. In the era of contemporary organized athletics, the absence of an EAP at any level of competition, from youth to professional leagues, is unacceptable. Effective EAPs must be developed, documented, and rehearsed at regular intervals. For the health and safety of competitive soccer players, as well as coaching staff and spectators, these steps are of critical importance.

HEAT

Heat-related illnesses can be serious and, at times, even life threatening. It is important for athletic staff and athletes to be well versed in the prevention, signs and symptoms, and treatment of heat-related illnesses in order to prevent serious and lasting injury. We aim to educate physicians about the prevention, recognition, and management of heat-related injury, and stress the importance of similarly educating athletes and coaching staff.

Exertional heat illnesses most often occur at temperatures >86°F, however they can occur at any temperature with heavy exertion.²² Signs and symptoms can be nonspecific early on, including weakness, fatigue, headache, nausea, and dizziness. Later signs can include imbalance, altered mentation, confusion, and behavior that is out of character such as irritability or aggression.²³ It is easy to see how the later signs can be confused for concussion in the right context. We cover the recognition and treatment of two common and serious heat-related illnesses: heat exhaustion and exertional heat stroke (EHS).

HEAT EXHAUSTION

Heat exhaustion occurs when an athlete cannot continue to exercise due to weakness and fatigue. While the exact mechanism is not well understood, it has been established that the combined effect of heat and dehydration have been proven to decrease exercise capacity and performance to a greater degree than either alone. The heat created by the body during exercise is 15 to 20 times greater than when at rest, and can increase core body temperature by 1°C every 5 minutes if no heat is lost, such as through sweating.²⁴ Additionally, when fluid deficits reach >3% to 5% of total body water, sweat production and skin blood flow decline, blunting the ability for the body to cool itself and causing progressive elevation of core body temperature if the athlete continues exerting him or herself. When fluid deficits reach 6% to 10%, cardiac output, sweat, and muscle blood flow decrease, likely leading to the symptoms seen with heat exhaustion: weakness, profound fatigue, and occasionally confusion and disorientation. Athletes with suspected heat exhaustion should be moved to a cooler area, laid down with legs elevated, and orally rehydrated. If they do not improve with oral rehydration, they may require intravenous fluids. The diagnosis of heat exhaustion hinges on a rectal temperature of <104°F; if >104°F the athlete should be presumed to have heat stroke, which will be addressed in the following paragraphs. Players can be cleared to return to play in mild cases within 24 to 48 hours with gradual increases in exercise intensity.²⁴

EXERTIONAL HEAT STROKE

EHS occurs when the body can no longer regulate the core body temperature and it rises to upwards of 104°F. In EHS, elevated core body temperature is associated with evidence of end organ dysfunction. The most easily identified on the playing field is likely central nervous system dysfunction, including irritability, confusion, irrational behavior, lethargy, dizziness, confusion, and even loss of consciousness. Temperature should be measured with rectal temperature only, as other methods of measurement have been shown to be consistently inaccurate.²² Heat stroke can be confused with exertional hyponatremia, heat exhaustion, or concussion, especially when core body temperature cannot be determined. However, EHS should always be the presumed cause of altered mentation when no rectal temperature is available because rapid cooling is critical to minimizing lasting effects. Morbidity and mortality are directly related to the length of time required to cool the athlete under 40°C (104°F).²⁴ Cooling should be completed on site prior to transport to a medical facility and is best achieved with submersion in an ice bath (ie, a kiddie pool or soaking tub full of ice and water).^22,25 If an ice bath is not available, ice bags should be applied to the neck axilla and groin and exchanged for fresh bags every 2 to 3 minutes.²² Ice bags have been shown to be inferior to whole body cooling, only cooling the athlete .04°C to .08°C/min compared to .15°C to .24°C/min with the ice bath.²⁴ All other tests should be delayed until cooling is achieved, unless they can be completed while cooling the athlete. The athlete can be removed from the ice bath once rectal temperatures reach <101°F to 102°F.²³ If the athlete returns to baseline after cooling, transportation to a medical facility may not be necessary. However, they should refrain from physical activity and heat exposure for at least 7 days and should be evaluated by a physician at that time. If all labs are normal and the athlete is asymptomatic, they can start progressive return to play under the direction of an athletic trainer or a sports medicine physician.²³

Continue to: HEAT-RELATED ILLNESS...

 

 

HEAT-RELATED ILLNESS

It is impossible to predict exactly which athletes will be most at risk for heat-related illness, so it is important to have a high degree of suspicion when environmental conditions are right. Athletes with recent illness, fever, or lack of sleep are at higher risk. Additional intrinsic risk factors include low fitness level, obesity, and inadequate hydration. Athletes who are highly competitive or motivated can be more likely to push through the early signs of illness or be reluctant to report symptoms.²³ Those with a history of exertional heat illness are more at risk for developing it again in the future.²³

The extrinsic risk factors for the development of heat-related illness are much easier to identify and modify in order to keep athletes safe. High temperature and high humidity conditions, heavy sun exposure, and exposure to similar conditions the preceding day put athletes at risk for exertional heat illness. Risks are even greater when the exercise is prolonged or intense with few breaks and access to hydration is limited.²³ Therefore, prevention of exertional heat illness is centered on these external risk factors.

Each team should have a heat policy as part of their EAP aimed at prevention and early recognition of heat-related illness. This policy should be shared with all athletes and coaches. The plan should be centered on acclimatization, activity modification, and early recognition and management as previously discussed. The US Soccer Federation “Recognize to Recover” Heat Guidelines suggest a 3-step process for appropriate activity modification:²²

1. Find the wet bulb globe temperature, either using a wet bulb globe thermometer or the temperature and humidity (Figure 1).

2. Find your regional weather category on the map (Figure 2).

3. Find your alert level and work to rest ratio recommendations (Figure 3).

Scheduled hydration breaks should be given as listed in Figure 3. Breaks of 4 minutes should be given for each 30 minutes of continuous practice or play. In a regulation 90-minute match, a hydration break should be given at 30 and 75 minutes (with half time at 45 minutes) at minimum. Athletes should be educated about where hydration can be accessed, and given unlimited access to hydration even outside of planned breaks.²²

Acclimatization to conditions is another integral part of preventing heat-related illness. It allows the body time to adapt to exercising in heat gradually, with a measured progression of exertion over the course of 10 to 14 days. The “Recognize to Recover” Heat Guidelines also provide guidance on acclimatization, and specifics can be found on the website.¹ Generally speaking, the warmest part of the day, usually between 11 AM and 4 PM, should be avoided for all training sessions, and length of practice and exertion should be gradually increased over 2 weeks.²²

In summary, appropriate acclimatization, hydration, activity modification, and education of athletes and staff are essential for the prevention of heat-related illness. Athletes and staff should understand the signs and symptoms of heat-related illness so that it can be recognized early and treated appropriately. If an athlete is altered in the heat and rectal temperature is >104°F or rectal temperature cannot be obtained, rapid cooling using an ice bath or ice bags is essential to prevent the morbidity and mortality associated with EHS. Above all, teams should have an explicit plan that includes protocols for acclimatization, activity modification, and all necessary equipment to prevent and treat heat-related illnesses should they occur, and ultimately keep athletes safe and healthy.

ABSTRACT

Soccer requires significant physical conditioning and endurance, as well as the physicality required for contact play. In order to keep athletes safe, it is important that coaches, medical staff, and the players themselves are educated on the most common dangers to their health that they may encounter on a soccer pitch. This article aims to review the current literature and recommendations on concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer, with a goal of educating all those who help to keep athletes healthy and competing to their full potential.  

Continue to: Soccer is one of the most popular sports...

Soccer is one of the most popular sports in the modern world and requires significant physical conditioning and endurance, as well as the physicality required for contact play. This article covers the topics of concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer players. We provide a review of the prevention, recognition, and management required to keep athletes safe on the soccer pitch, both in practice and in competitive play.

HEAD

With an estimated 1.6 to 3.8 million sports-related mild traumatic brain injuries (ie, concussions) occurring annually in the United States,¹ there has been an appropriate increase in the focus on prevention and treatment of these injuries. For more than a decade the spotlight has been on concussions that occur in American football, but other sports have also had to examine the prevalence of concussions in their sport. This is certainly true for soccer.

There has been a steady increase in soccer participation in the United States. From 1973 to 2014 there was a 4-fold increase in high school boys and a 35-fold increase in high school girls playing soccer.² Currently, there are more than 3.7 million youth who play on teams under the supervision of the US Soccer Federation, the sport’s national governing body.³ With the growth of the sport, there has also been an intensified focus on injury prevention in soccer players, including concussive brain injuries.

A recent study examined injury rates in high school soccer players and noted that concussion is the second most common injury (17.9%), after ligament sprains (29.7%).⁴ The overall injury rate was 2.06 per 1000 athletic exposures (AEs [defined as participation in practice or game play]), but higher in games (4.42 per 1000 AEs) than during practices (1.05 per 1000 AEs). The overall concussion rate was 0.36 per 1000 AEs.⁴

Most concussions (54.8%) resulted in missing play between 1 to 3 weeks, but a sizeable portion of the athletes (14.9%) were out of play for more than 3 weeks. Additionally, 10.7% of all medical disqualifications were due to concussive injuries. Khodaee and colleagues⁴ found no statistically significant difference in concussion rates between male and female soccer players over the 9-year period of time that they examined, however previous studies have found higher rates in female athletes.⁵

In soccer, as in other sports, there is a concern about both the adequate recognition of concussions during practice and play and the underreporting of concussions by athletes. The US Soccer Federation has taken a proactive stance on addressing concussion in youth soccer by developing the “Recognize to Recover” program.⁶ Recognize to Recover is the US Soccer Federation’s “comprehensive player health and safety program aimed at promoting safe play and reducing injuries in soccer players of all ages.” The website provides an educational video geared toward players, along with links to concussion assessment tools, the US Soccer Federation Concussion Protocol, and US Soccer Federation-Centers for Disease Control fact sheets for athletes, parents, and coaches.⁶

Continue to: A challenge for all sports...

 

 

A challenge for all sports is allowing adequate evaluation of a suspected concussion by properly trained healthcare professionals. The 2017 Berlin Concussion in Sport Group position paper stated, “when a concussion is suspected, the athlete should be removed from the sporting environment and a multimodal assessment should be conducted in standardized fashion (eg, Sport Concussion Assessment Tool- 5th edition). Sporting bodies should allow adequate time to conduct this evaluation.”⁷ However, the International Federation of Football Association (FIFA) rules limit substitutions to 3 over the course of the game, which can make a thorough evaluation of players difficult as trainers and coaches are under increased pressure to quickly determine whether to use one of their valuable substitutions. Fortunately, the National Collegiate Athletic Association (NCAA) soccer has mitigated this issue by allowing unlimited substitutions during matches, and high school teams generally follow similar rules.

One of the goals of any safety education program is not only to raise the awareness of the signs and symptoms of concussion by all those involved in the sport, but also to increase the number of athletes who self-report their symptoms and decrease those who hide any possible concussions. A study found that a majority (58.6%) of middle school soccer players continued to play while experiencing concussion symptoms.⁵ However, in a very recent (not yet published) study, 92% of US Soccer Federation players reported that they did seek out a medical evaluation for their concussion.⁸ This is certainly a positive sign and further research needs to clarify what methods of education or training will maintain this level of self-reporting in soccer players.

There has also been an increased focus on understanding the mechanism of injury of concussions. In soccer, concussions can occur from player-to-player contact, contact with the player surface, contact with playing apparatus (eg, goal posts) and non-contact mechanisms. While there has been a focus on concussions from heading the ball, player-to-player contact is the most common cause of concussions. A 2017 study of 7- to 12-year-old soccer players in 4 European countries found that about 1 out of 10 concussions were caused by heading the ball.⁹ Comstock and colleageues¹⁰ found slightly higher numbers, roughly 25% to 30% (depending on gender), but 70% to 78% (again depending on gender) of those were caused by player-to-player contact rather than contact with the ball.

To date there has not been any meta-analytic review evaluating the cognitive and physical symptoms associated with heading in soccer. A recent review paper stated that the “current evidence seems insufficient to support a ban of heading in children’s football (soccer).”¹⁰ However, in December 2015 the US Soccer Federation included age-specific heading limitations. Players ages 10 years and under “shall not engage in heading, either in practices or in games” and players age 11 years and 12 years should have “limited heading in practice; maximum of 30 minutes of heading training per week, with no more than 15-20 headers per player, per week.”¹¹ US Soccer Federation officials acknowledged the limitations in the current science regarding heading in young soccer players but chose to err on the side of caution until further empirical evidence regarding the risks associated with repetitive heading is available.

The US Soccer Federation is also exploring other ways to reduce the incidence rate of concussions, including ensuring that the age-appropriate sized ball is used in practice and play, possible rule changes, evaluation of different playing surfaces, and equipment usage. To date, there is no strong evidence to support the use of mouth guards or helmets to reduce concussions in soccer. Additionally, the current data about the value of head impact sensors in soccer has not supported its widespread use.

Continue to: Finally, the issue of the prevalence...

 

 

Finally, the issue of the prevalence of chronic traumatic encephalopathy (CTE) in soccer players is beyond the scope of this article. The expert opinion from the 2017 US Soccer Federation, Major League Soccer (MLS), and National Women’s Soccer League (NWSL) conference concluded, “At present, no data exist that support that soccer participation is a risk factor for the development of neurodegenerative disease. Similarly, at this time, consistent with evidence discussed in the Berlin Concussion in Sport Group (CISG) Consensus Conference, our review suggests no causal relationship has been demonstrated between soccer and CTE pathology.”¹²

The more we know about concussions, both in general and those sustained during soccer play, the better we are able to diagnose and manage these injuries in our athletes. An important step is creating evidence-based protocols that evolve as our knowledge of concussions does as well. In April 2017, the US Soccer Federation, MLS, and the NWSL held a joint summit entitled, “Head Injury in Soccer: From Science to the Field” to address the current evidence-based science of concussions in soccer.⁸ An article discussing the findings of this meeting is forthcoming and will undoubtedly guide further development of concussion protocols for soccer players of all ages.

HEART

The physiologic demands of soccer place considerable stress on the cardiovascular system. Participation in training and competition is characterized by a combination of aerobic and anaerobic physiology with the typical athlete covering approximately 10 km over the course of the 90-minute match. The primary role of the heart and blood vessels is to supply the exercising skeletal muscle with oxygen and energy substrate and to clear the byproducts of metabolism. Among healthy athletes without cardiovascular disease, these processes are typically well tolerated and may be associated with beneficial cardiovascular adaptations over time. However, competitive soccer players are not completely immune to cardiovascular disease. Athletes across the age and competition spectrum may develop symptoms suggestive of underlying cardiovascular disease during play including exertional chest pain, inappropriate shortness of breath, palpitations, and syncope. These athletes require timely clinical evaluation. In extremely rare but high visibility cases, competitive soccer players may succumb to cardiac arrest on the pitch, underscoring the need for comprehensive emergency action plans (EAPs). We provide the practicing clinician with an overview of cardiovascular issues relevant to the competitive soccer athlete.

CARDIOVASCULAR ADAPTATIONS TO SPORT

The pressure (ie, repetitive surges in systemic blood pressure) and volume (ie, sustained increases in high cardiac output) challenges inherent in soccer participation place stress on the cardiovascular system. Healthy athletes across the age spectrum typically tolerate the hemodynamic stressors of participation without issues. Athletes that engage in training and competition over months to years often develop beneficial adaptations of the cardiovascular system that enhance on-field performance and contribute to optimal long-term health. Detailed discussion of how the heart and blood vessels respond to exercise training is beyond the scope of this article, but the interested reader is referred to several prior publications.^13,14 In brief, the heart of the healthy soccer athlete demonstrates the balanced mild chamber dilation and wall thickening characteristic of left ventricular eccentric remodeling. This form of exercise-induced cardiac remodeling facilitates maintenance of high stroke volume during exercise with minimal increases in cardiac work. In parallel, routine aerobic exercise training confers favorable changes in the systemic arterial system, which leads to reductions in age-associated ventricular stiffening and maintenance of healthy low blood pressure. It must be emphasized that the healthy heart muscle dilation and thickening that develop in response to sports participation, regardless of age, ethnicity, or gender, are relatively mild and should not be confused with common forms of heart muscle disease that may be seen in athletes at risk for adverse outcomes. In some situations, consultation with an extreme sports cardiologist may be required to differentiate exercise-induced remodeling from over heart muscle pathology.¹⁵

Continue to: THE SYMPTOMATIC ATHLETE...

 

 

THE SYMPTOMATIC ATHLETE

Any athlete presenting with symptoms suggestive of underlying cardiovascular disease should be withheld from training and competition until a comprehensive clinical evaluation has been completed. Common manifestations of underlying heart disease that occur in soccer players include exertional chest pain/pressure/tightness, shortness of breath that is out of proportion to workload, palpitations or the perception of irregular cardiac activity, and syncope. Chest discomfort, inappropriate shortness of breath, and palpitations that occur during training or competition should be managed with immediate removal from the playing field and prompt medical assessment. In many cases, thorough evaluation will involve collaboration between sports medicine and sports cardiology providers. Evaluations must be individualized on a case-by-case basis as tailored to the athlete’s presenting chief complaint and prior medical history. Most of these assessments will include a detailed medical history and physical examination, a 12-lead electrocardiogram (ECG), provocative exercise testing in a controlled environment, noninvasive cardiac imaging, and in some cases ambulatory rhythm monitoring. Uniformly, the athlete should be withheld from further training and competition until high-risk cardiovascular disease has been excluded. We refer the interested reader to a comprehensive discussion of symptom-based assessment of the athlete with suspected cardiovascular disease.¹⁶

Syncope (sudden and abrupt loss of consciousness with spontaneous neurologic recovery) is common among trained athletes. The vast majority of syncope is caused by “neurocardiogenic” mechanisms and carries a benign prognosis. Benign neurally-mediated syncope most often occurs outside of training and competition among athletes with heightened vagal tone and a predisposed susceptibility to triggers including pain, anxiety, emotional stimulation, and sudden postural change. Athletes who experience neurally-mediated syncope outside of training and competition routinely report a pre-event prodrome or aura that permits them to lower themselves to the ground, thereby avoiding injury. A distinct, but similarly benign and common, form of neurally-mediated fainting is post-exertional syncope. Here, fainting occurs within seconds of abrupt termination of exercise due to a rapid reduction cardiac preload and corollary cerebral blood supply. When either form of neurally-mediated syncope is suggested by a comprehensive medical history, normal physical examination, and a normal 12- lead ECG, further evaluation is unnecessary. However, the athlete and their coaching staff should be educated about avoidance tactics including hydration, dietary sodium supplementation, and avoidance of abrupt exercise termination as neutrally-mediated syncope tends to be recurrent without such measures. Fainting episodes that occur during training or competition that are not clearly post-exertional should be considered a medical emergency and should prompt comprehensive evaluation by a qualified cardiovascular specialist. Working closely with team physicians and athletic training staff, it is the responsibility of sports cardiologists to exclude potentially life-threatening forms of electrical, muscular, coronary, and valvular heart disease. Ideally, this evaluation should be conducted rapidly to avoid unnecessary delays in return to play.

CARDIAC ARREST AND SUDDEN DEATH

Numerous high-visibility cases of cardiac arrest on the soccer pitch have alerted the sporting community to the potential for these rare and potentially tragic events. Definitive incidence statistics defining the risk of cardiac arrest among soccer players are lacking. Data from the NCAA database suggest a sudden death incidence rate among collegiate male soccer athletes of approximately 1:24,000 athlete years.⁸ Similar data documenting incidence among female athletes and among those at lower (ie, youth level and high school) and higher (ie, professional) levels of play are unavailable. Underlying cardiovascular disease in the forms of heart muscle abnormalities (ie, genetic and acquired cardiomyopathy), coronary artery abnormalities (ie, genetic coronary anomalies and atherosclerotic coronary disease), valvular heart problems (ie, congenitally malformed aortic valves), and primary disturbances of the cardiac electrical system (ie, Wolf-Parkinson-White syndrome, long QT syndrome, etc.) explain a substantial percentage of on-pitch cardiac arrest. However, it is increasingly recognized that a significant minority of sudden cardiac deaths among athletes occur in the absence of attributable cardiovascular abnormality.¹⁷ Such cases, often referred to as “sudden unexplained death,” present unique challenges in the context of pre-participation screening, as they are undetectable and thus unpredictable.

Reduction of cardiac arrest and sudden death may best be accomplished through a combination of focused pre-participation screening and the development and implementation of a comprehensive EAP. Pre-participation involves the performance of a battery of tests prior to training and competition that are geared toward the detection of occult high-risk cardiovascular disease. Recommendations regarding pre-participation screening vary both across and within countries. Current US recommendations call for a focused medical history and physical examination prior to training and competition with consideration of the addition of a 12-lead ECG on a local level based on expertise and available resources.¹⁸ Conversely, current European guidelines including those endorsed by FIFA, suggest routine inclusion of a 12-lead ECG and in some cases, a transthoracic ECG.¹⁹ It must be emphasized that no screening approach has been confirmed to reduce the incidence of sudden death, and the decision to extend screening beyond the medical history and physical examination to include a 12-lead ECG or echocardiogram may come at the cost of increased false positive testing. In practice, decisions about how and when to screen are ideally made at a local level after consideration of medical and financial resources.²⁰

Continue to: Even the most comprehensive approach...

 

 

Even the most comprehensive approach to screening and evaluation of symptomatic athletes will not completely eliminate on-pitch cardiac arrest. Thus, all stakeholders that engage in the oversight of organized soccer must be committed to the development and implementation of an EAP.²¹ Key components of an effective EAP include the training of coaching staff, athletic trainers, and players in basic cardiopulmonary resuscitation, access to and training in the use of automated external defibrillators, and a triage/transport protocol that ensures timely access to advanced cardiac life support. Much like screening, emergency action planning involving these key core components must be developed and tailored locally. In the era of contemporary organized athletics, the absence of an EAP at any level of competition, from youth to professional leagues, is unacceptable. Effective EAPs must be developed, documented, and rehearsed at regular intervals. For the health and safety of competitive soccer players, as well as coaching staff and spectators, these steps are of critical importance.

HEAT

Heat-related illnesses can be serious and, at times, even life threatening. It is important for athletic staff and athletes to be well versed in the prevention, signs and symptoms, and treatment of heat-related illnesses in order to prevent serious and lasting injury. We aim to educate physicians about the prevention, recognition, and management of heat-related injury, and stress the importance of similarly educating athletes and coaching staff.

Exertional heat illnesses most often occur at temperatures >86°F, however they can occur at any temperature with heavy exertion.²² Signs and symptoms can be nonspecific early on, including weakness, fatigue, headache, nausea, and dizziness. Later signs can include imbalance, altered mentation, confusion, and behavior that is out of character such as irritability or aggression.²³ It is easy to see how the later signs can be confused for concussion in the right context. We cover the recognition and treatment of two common and serious heat-related illnesses: heat exhaustion and exertional heat stroke (EHS).

HEAT EXHAUSTION

Heat exhaustion occurs when an athlete cannot continue to exercise due to weakness and fatigue. While the exact mechanism is not well understood, it has been established that the combined effect of heat and dehydration have been proven to decrease exercise capacity and performance to a greater degree than either alone. The heat created by the body during exercise is 15 to 20 times greater than when at rest, and can increase core body temperature by 1°C every 5 minutes if no heat is lost, such as through sweating.²⁴ Additionally, when fluid deficits reach >3% to 5% of total body water, sweat production and skin blood flow decline, blunting the ability for the body to cool itself and causing progressive elevation of core body temperature if the athlete continues exerting him or herself. When fluid deficits reach 6% to 10%, cardiac output, sweat, and muscle blood flow decrease, likely leading to the symptoms seen with heat exhaustion: weakness, profound fatigue, and occasionally confusion and disorientation. Athletes with suspected heat exhaustion should be moved to a cooler area, laid down with legs elevated, and orally rehydrated. If they do not improve with oral rehydration, they may require intravenous fluids. The diagnosis of heat exhaustion hinges on a rectal temperature of <104°F; if >104°F the athlete should be presumed to have heat stroke, which will be addressed in the following paragraphs. Players can be cleared to return to play in mild cases within 24 to 48 hours with gradual increases in exercise intensity.²⁴

EXERTIONAL HEAT STROKE

EHS occurs when the body can no longer regulate the core body temperature and it rises to upwards of 104°F. In EHS, elevated core body temperature is associated with evidence of end organ dysfunction. The most easily identified on the playing field is likely central nervous system dysfunction, including irritability, confusion, irrational behavior, lethargy, dizziness, confusion, and even loss of consciousness. Temperature should be measured with rectal temperature only, as other methods of measurement have been shown to be consistently inaccurate.²² Heat stroke can be confused with exertional hyponatremia, heat exhaustion, or concussion, especially when core body temperature cannot be determined. However, EHS should always be the presumed cause of altered mentation when no rectal temperature is available because rapid cooling is critical to minimizing lasting effects. Morbidity and mortality are directly related to the length of time required to cool the athlete under 40°C (104°F).²⁴ Cooling should be completed on site prior to transport to a medical facility and is best achieved with submersion in an ice bath (ie, a kiddie pool or soaking tub full of ice and water).^22,25 If an ice bath is not available, ice bags should be applied to the neck axilla and groin and exchanged for fresh bags every 2 to 3 minutes.²² Ice bags have been shown to be inferior to whole body cooling, only cooling the athlete .04°C to .08°C/min compared to .15°C to .24°C/min with the ice bath.²⁴ All other tests should be delayed until cooling is achieved, unless they can be completed while cooling the athlete. The athlete can be removed from the ice bath once rectal temperatures reach <101°F to 102°F.²³ If the athlete returns to baseline after cooling, transportation to a medical facility may not be necessary. However, they should refrain from physical activity and heat exposure for at least 7 days and should be evaluated by a physician at that time. If all labs are normal and the athlete is asymptomatic, they can start progressive return to play under the direction of an athletic trainer or a sports medicine physician.²³

Continue to: HEAT-RELATED ILLNESS...

 

 

HEAT-RELATED ILLNESS

It is impossible to predict exactly which athletes will be most at risk for heat-related illness, so it is important to have a high degree of suspicion when environmental conditions are right. Athletes with recent illness, fever, or lack of sleep are at higher risk. Additional intrinsic risk factors include low fitness level, obesity, and inadequate hydration. Athletes who are highly competitive or motivated can be more likely to push through the early signs of illness or be reluctant to report symptoms.²³ Those with a history of exertional heat illness are more at risk for developing it again in the future.²³

The extrinsic risk factors for the development of heat-related illness are much easier to identify and modify in order to keep athletes safe. High temperature and high humidity conditions, heavy sun exposure, and exposure to similar conditions the preceding day put athletes at risk for exertional heat illness. Risks are even greater when the exercise is prolonged or intense with few breaks and access to hydration is limited.²³ Therefore, prevention of exertional heat illness is centered on these external risk factors.

Each team should have a heat policy as part of their EAP aimed at prevention and early recognition of heat-related illness. This policy should be shared with all athletes and coaches. The plan should be centered on acclimatization, activity modification, and early recognition and management as previously discussed. The US Soccer Federation “Recognize to Recover” Heat Guidelines suggest a 3-step process for appropriate activity modification:²²

1. Find the wet bulb globe temperature, either using a wet bulb globe thermometer or the temperature and humidity (Figure 1).

2. Find your regional weather category on the map (Figure 2).

3. Find your alert level and work to rest ratio recommendations (Figure 3).

Scheduled hydration breaks should be given as listed in Figure 3. Breaks of 4 minutes should be given for each 30 minutes of continuous practice or play. In a regulation 90-minute match, a hydration break should be given at 30 and 75 minutes (with half time at 45 minutes) at minimum. Athletes should be educated about where hydration can be accessed, and given unlimited access to hydration even outside of planned breaks.²²

Acclimatization to conditions is another integral part of preventing heat-related illness. It allows the body time to adapt to exercising in heat gradually, with a measured progression of exertion over the course of 10 to 14 days. The “Recognize to Recover” Heat Guidelines also provide guidance on acclimatization, and specifics can be found on the website.¹ Generally speaking, the warmest part of the day, usually between 11 AM and 4 PM, should be avoided for all training sessions, and length of practice and exertion should be gradually increased over 2 weeks.²²

In summary, appropriate acclimatization, hydration, activity modification, and education of athletes and staff are essential for the prevention of heat-related illness. Athletes and staff should understand the signs and symptoms of heat-related illness so that it can be recognized early and treated appropriately. If an athlete is altered in the heat and rectal temperature is >104°F or rectal temperature cannot be obtained, rapid cooling using an ice bath or ice bags is essential to prevent the morbidity and mortality associated with EHS. Above all, teams should have an explicit plan that includes protocols for acclimatization, activity modification, and all necessary equipment to prevent and treat heat-related illnesses should they occur, and ultimately keep athletes safe and healthy.

ABSTRACT

Soccer requires significant physical conditioning and endurance, as well as the physicality required for contact play. In order to keep athletes safe, it is important that coaches, medical staff, and the players themselves are educated on the most common dangers to their health that they may encounter on a soccer pitch. This article aims to review the current literature and recommendations on concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer, with a goal of educating all those who help to keep athletes healthy and competing to their full potential.  

Continue to: Soccer is one of the most popular sports...

Soccer is one of the most popular sports in the modern world and requires significant physical conditioning and endurance, as well as the physicality required for contact play. This article covers the topics of concussion, cardiovascular considerations, and heat-related illness as they relate to competitive soccer players. We provide a review of the prevention, recognition, and management required to keep athletes safe on the soccer pitch, both in practice and in competitive play.

HEAD

With an estimated 1.6 to 3.8 million sports-related mild traumatic brain injuries (ie, concussions) occurring annually in the United States,¹ there has been an appropriate increase in the focus on prevention and treatment of these injuries. For more than a decade the spotlight has been on concussions that occur in American football, but other sports have also had to examine the prevalence of concussions in their sport. This is certainly true for soccer.

There has been a steady increase in soccer participation in the United States. From 1973 to 2014 there was a 4-fold increase in high school boys and a 35-fold increase in high school girls playing soccer.² Currently, there are more than 3.7 million youth who play on teams under the supervision of the US Soccer Federation, the sport’s national governing body.³ With the growth of the sport, there has also been an intensified focus on injury prevention in soccer players, including concussive brain injuries.

A recent study examined injury rates in high school soccer players and noted that concussion is the second most common injury (17.9%), after ligament sprains (29.7%).⁴ The overall injury rate was 2.06 per 1000 athletic exposures (AEs [defined as participation in practice or game play]), but higher in games (4.42 per 1000 AEs) than during practices (1.05 per 1000 AEs). The overall concussion rate was 0.36 per 1000 AEs.⁴

Most concussions (54.8%) resulted in missing play between 1 to 3 weeks, but a sizeable portion of the athletes (14.9%) were out of play for more than 3 weeks. Additionally, 10.7% of all medical disqualifications were due to concussive injuries. Khodaee and colleagues⁴ found no statistically significant difference in concussion rates between male and female soccer players over the 9-year period of time that they examined, however previous studies have found higher rates in female athletes.⁵

In soccer, as in other sports, there is a concern about both the adequate recognition of concussions during practice and play and the underreporting of concussions by athletes. The US Soccer Federation has taken a proactive stance on addressing concussion in youth soccer by developing the “Recognize to Recover” program.⁶ Recognize to Recover is the US Soccer Federation’s “comprehensive player health and safety program aimed at promoting safe play and reducing injuries in soccer players of all ages.” The website provides an educational video geared toward players, along with links to concussion assessment tools, the US Soccer Federation Concussion Protocol, and US Soccer Federation-Centers for Disease Control fact sheets for athletes, parents, and coaches.⁶

Continue to: A challenge for all sports...

 

 

A challenge for all sports is allowing adequate evaluation of a suspected concussion by properly trained healthcare professionals. The 2017 Berlin Concussion in Sport Group position paper stated, “when a concussion is suspected, the athlete should be removed from the sporting environment and a multimodal assessment should be conducted in standardized fashion (eg, Sport Concussion Assessment Tool- 5th edition). Sporting bodies should allow adequate time to conduct this evaluation.”⁷ However, the International Federation of Football Association (FIFA) rules limit substitutions to 3 over the course of the game, which can make a thorough evaluation of players difficult as trainers and coaches are under increased pressure to quickly determine whether to use one of their valuable substitutions. Fortunately, the National Collegiate Athletic Association (NCAA) soccer has mitigated this issue by allowing unlimited substitutions during matches, and high school teams generally follow similar rules.

One of the goals of any safety education program is not only to raise the awareness of the signs and symptoms of concussion by all those involved in the sport, but also to increase the number of athletes who self-report their symptoms and decrease those who hide any possible concussions. A study found that a majority (58.6%) of middle school soccer players continued to play while experiencing concussion symptoms.⁵ However, in a very recent (not yet published) study, 92% of US Soccer Federation players reported that they did seek out a medical evaluation for their concussion.⁸ This is certainly a positive sign and further research needs to clarify what methods of education or training will maintain this level of self-reporting in soccer players.

There has also been an increased focus on understanding the mechanism of injury of concussions. In soccer, concussions can occur from player-to-player contact, contact with the player surface, contact with playing apparatus (eg, goal posts) and non-contact mechanisms. While there has been a focus on concussions from heading the ball, player-to-player contact is the most common cause of concussions. A 2017 study of 7- to 12-year-old soccer players in 4 European countries found that about 1 out of 10 concussions were caused by heading the ball.⁹ Comstock and colleageues¹⁰ found slightly higher numbers, roughly 25% to 30% (depending on gender), but 70% to 78% (again depending on gender) of those were caused by player-to-player contact rather than contact with the ball.

To date there has not been any meta-analytic review evaluating the cognitive and physical symptoms associated with heading in soccer. A recent review paper stated that the “current evidence seems insufficient to support a ban of heading in children’s football (soccer).”¹⁰ However, in December 2015 the US Soccer Federation included age-specific heading limitations. Players ages 10 years and under “shall not engage in heading, either in practices or in games” and players age 11 years and 12 years should have “limited heading in practice; maximum of 30 minutes of heading training per week, with no more than 15-20 headers per player, per week.”¹¹ US Soccer Federation officials acknowledged the limitations in the current science regarding heading in young soccer players but chose to err on the side of caution until further empirical evidence regarding the risks associated with repetitive heading is available.

The US Soccer Federation is also exploring other ways to reduce the incidence rate of concussions, including ensuring that the age-appropriate sized ball is used in practice and play, possible rule changes, evaluation of different playing surfaces, and equipment usage. To date, there is no strong evidence to support the use of mouth guards or helmets to reduce concussions in soccer. Additionally, the current data about the value of head impact sensors in soccer has not supported its widespread use.

Continue to: Finally, the issue of the prevalence...

 

 

Finally, the issue of the prevalence of chronic traumatic encephalopathy (CTE) in soccer players is beyond the scope of this article. The expert opinion from the 2017 US Soccer Federation, Major League Soccer (MLS), and National Women’s Soccer League (NWSL) conference concluded, “At present, no data exist that support that soccer participation is a risk factor for the development of neurodegenerative disease. Similarly, at this time, consistent with evidence discussed in the Berlin Concussion in Sport Group (CISG) Consensus Conference, our review suggests no causal relationship has been demonstrated between soccer and CTE pathology.”¹²

The more we know about concussions, both in general and those sustained during soccer play, the better we are able to diagnose and manage these injuries in our athletes. An important step is creating evidence-based protocols that evolve as our knowledge of concussions does as well. In April 2017, the US Soccer Federation, MLS, and the NWSL held a joint summit entitled, “Head Injury in Soccer: From Science to the Field” to address the current evidence-based science of concussions in soccer.⁸ An article discussing the findings of this meeting is forthcoming and will undoubtedly guide further development of concussion protocols for soccer players of all ages.

HEART

The physiologic demands of soccer place considerable stress on the cardiovascular system. Participation in training and competition is characterized by a combination of aerobic and anaerobic physiology with the typical athlete covering approximately 10 km over the course of the 90-minute match. The primary role of the heart and blood vessels is to supply the exercising skeletal muscle with oxygen and energy substrate and to clear the byproducts of metabolism. Among healthy athletes without cardiovascular disease, these processes are typically well tolerated and may be associated with beneficial cardiovascular adaptations over time. However, competitive soccer players are not completely immune to cardiovascular disease. Athletes across the age and competition spectrum may develop symptoms suggestive of underlying cardiovascular disease during play including exertional chest pain, inappropriate shortness of breath, palpitations, and syncope. These athletes require timely clinical evaluation. In extremely rare but high visibility cases, competitive soccer players may succumb to cardiac arrest on the pitch, underscoring the need for comprehensive emergency action plans (EAPs). We provide the practicing clinician with an overview of cardiovascular issues relevant to the competitive soccer athlete.

CARDIOVASCULAR ADAPTATIONS TO SPORT

The pressure (ie, repetitive surges in systemic blood pressure) and volume (ie, sustained increases in high cardiac output) challenges inherent in soccer participation place stress on the cardiovascular system. Healthy athletes across the age spectrum typically tolerate the hemodynamic stressors of participation without issues. Athletes that engage in training and competition over months to years often develop beneficial adaptations of the cardiovascular system that enhance on-field performance and contribute to optimal long-term health. Detailed discussion of how the heart and blood vessels respond to exercise training is beyond the scope of this article, but the interested reader is referred to several prior publications.^13,14 In brief, the heart of the healthy soccer athlete demonstrates the balanced mild chamber dilation and wall thickening characteristic of left ventricular eccentric remodeling. This form of exercise-induced cardiac remodeling facilitates maintenance of high stroke volume during exercise with minimal increases in cardiac work. In parallel, routine aerobic exercise training confers favorable changes in the systemic arterial system, which leads to reductions in age-associated ventricular stiffening and maintenance of healthy low blood pressure. It must be emphasized that the healthy heart muscle dilation and thickening that develop in response to sports participation, regardless of age, ethnicity, or gender, are relatively mild and should not be confused with common forms of heart muscle disease that may be seen in athletes at risk for adverse outcomes. In some situations, consultation with an extreme sports cardiologist may be required to differentiate exercise-induced remodeling from over heart muscle pathology.¹⁵

Continue to: THE SYMPTOMATIC ATHLETE...

 

 

THE SYMPTOMATIC ATHLETE

Any athlete presenting with symptoms suggestive of underlying cardiovascular disease should be withheld from training and competition until a comprehensive clinical evaluation has been completed. Common manifestations of underlying heart disease that occur in soccer players include exertional chest pain/pressure/tightness, shortness of breath that is out of proportion to workload, palpitations or the perception of irregular cardiac activity, and syncope. Chest discomfort, inappropriate shortness of breath, and palpitations that occur during training or competition should be managed with immediate removal from the playing field and prompt medical assessment. In many cases, thorough evaluation will involve collaboration between sports medicine and sports cardiology providers. Evaluations must be individualized on a case-by-case basis as tailored to the athlete’s presenting chief complaint and prior medical history. Most of these assessments will include a detailed medical history and physical examination, a 12-lead electrocardiogram (ECG), provocative exercise testing in a controlled environment, noninvasive cardiac imaging, and in some cases ambulatory rhythm monitoring. Uniformly, the athlete should be withheld from further training and competition until high-risk cardiovascular disease has been excluded. We refer the interested reader to a comprehensive discussion of symptom-based assessment of the athlete with suspected cardiovascular disease.¹⁶

Syncope (sudden and abrupt loss of consciousness with spontaneous neurologic recovery) is common among trained athletes. The vast majority of syncope is caused by “neurocardiogenic” mechanisms and carries a benign prognosis. Benign neurally-mediated syncope most often occurs outside of training and competition among athletes with heightened vagal tone and a predisposed susceptibility to triggers including pain, anxiety, emotional stimulation, and sudden postural change. Athletes who experience neurally-mediated syncope outside of training and competition routinely report a pre-event prodrome or aura that permits them to lower themselves to the ground, thereby avoiding injury. A distinct, but similarly benign and common, form of neurally-mediated fainting is post-exertional syncope. Here, fainting occurs within seconds of abrupt termination of exercise due to a rapid reduction cardiac preload and corollary cerebral blood supply. When either form of neurally-mediated syncope is suggested by a comprehensive medical history, normal physical examination, and a normal 12- lead ECG, further evaluation is unnecessary. However, the athlete and their coaching staff should be educated about avoidance tactics including hydration, dietary sodium supplementation, and avoidance of abrupt exercise termination as neutrally-mediated syncope tends to be recurrent without such measures. Fainting episodes that occur during training or competition that are not clearly post-exertional should be considered a medical emergency and should prompt comprehensive evaluation by a qualified cardiovascular specialist. Working closely with team physicians and athletic training staff, it is the responsibility of sports cardiologists to exclude potentially life-threatening forms of electrical, muscular, coronary, and valvular heart disease. Ideally, this evaluation should be conducted rapidly to avoid unnecessary delays in return to play.

CARDIAC ARREST AND SUDDEN DEATH

Numerous high-visibility cases of cardiac arrest on the soccer pitch have alerted the sporting community to the potential for these rare and potentially tragic events. Definitive incidence statistics defining the risk of cardiac arrest among soccer players are lacking. Data from the NCAA database suggest a sudden death incidence rate among collegiate male soccer athletes of approximately 1:24,000 athlete years.⁸ Similar data documenting incidence among female athletes and among those at lower (ie, youth level and high school) and higher (ie, professional) levels of play are unavailable. Underlying cardiovascular disease in the forms of heart muscle abnormalities (ie, genetic and acquired cardiomyopathy), coronary artery abnormalities (ie, genetic coronary anomalies and atherosclerotic coronary disease), valvular heart problems (ie, congenitally malformed aortic valves), and primary disturbances of the cardiac electrical system (ie, Wolf-Parkinson-White syndrome, long QT syndrome, etc.) explain a substantial percentage of on-pitch cardiac arrest. However, it is increasingly recognized that a significant minority of sudden cardiac deaths among athletes occur in the absence of attributable cardiovascular abnormality.¹⁷ Such cases, often referred to as “sudden unexplained death,” present unique challenges in the context of pre-participation screening, as they are undetectable and thus unpredictable.

Reduction of cardiac arrest and sudden death may best be accomplished through a combination of focused pre-participation screening and the development and implementation of a comprehensive EAP. Pre-participation involves the performance of a battery of tests prior to training and competition that are geared toward the detection of occult high-risk cardiovascular disease. Recommendations regarding pre-participation screening vary both across and within countries. Current US recommendations call for a focused medical history and physical examination prior to training and competition with consideration of the addition of a 12-lead ECG on a local level based on expertise and available resources.¹⁸ Conversely, current European guidelines including those endorsed by FIFA, suggest routine inclusion of a 12-lead ECG and in some cases, a transthoracic ECG.¹⁹ It must be emphasized that no screening approach has been confirmed to reduce the incidence of sudden death, and the decision to extend screening beyond the medical history and physical examination to include a 12-lead ECG or echocardiogram may come at the cost of increased false positive testing. In practice, decisions about how and when to screen are ideally made at a local level after consideration of medical and financial resources.²⁰

Continue to: Even the most comprehensive approach...

 

 

Even the most comprehensive approach to screening and evaluation of symptomatic athletes will not completely eliminate on-pitch cardiac arrest. Thus, all stakeholders that engage in the oversight of organized soccer must be committed to the development and implementation of an EAP.²¹ Key components of an effective EAP include the training of coaching staff, athletic trainers, and players in basic cardiopulmonary resuscitation, access to and training in the use of automated external defibrillators, and a triage/transport protocol that ensures timely access to advanced cardiac life support. Much like screening, emergency action planning involving these key core components must be developed and tailored locally. In the era of contemporary organized athletics, the absence of an EAP at any level of competition, from youth to professional leagues, is unacceptable. Effective EAPs must be developed, documented, and rehearsed at regular intervals. For the health and safety of competitive soccer players, as well as coaching staff and spectators, these steps are of critical importance.

HEAT

Heat-related illnesses can be serious and, at times, even life threatening. It is important for athletic staff and athletes to be well versed in the prevention, signs and symptoms, and treatment of heat-related illnesses in order to prevent serious and lasting injury. We aim to educate physicians about the prevention, recognition, and management of heat-related injury, and stress the importance of similarly educating athletes and coaching staff.

Exertional heat illnesses most often occur at temperatures >86°F, however they can occur at any temperature with heavy exertion.²² Signs and symptoms can be nonspecific early on, including weakness, fatigue, headache, nausea, and dizziness. Later signs can include imbalance, altered mentation, confusion, and behavior that is out of character such as irritability or aggression.²³ It is easy to see how the later signs can be confused for concussion in the right context. We cover the recognition and treatment of two common and serious heat-related illnesses: heat exhaustion and exertional heat stroke (EHS).

HEAT EXHAUSTION

Heat exhaustion occurs when an athlete cannot continue to exercise due to weakness and fatigue. While the exact mechanism is not well understood, it has been established that the combined effect of heat and dehydration have been proven to decrease exercise capacity and performance to a greater degree than either alone. The heat created by the body during exercise is 15 to 20 times greater than when at rest, and can increase core body temperature by 1°C every 5 minutes if no heat is lost, such as through sweating.²⁴ Additionally, when fluid deficits reach >3% to 5% of total body water, sweat production and skin blood flow decline, blunting the ability for the body to cool itself and causing progressive elevation of core body temperature if the athlete continues exerting him or herself. When fluid deficits reach 6% to 10%, cardiac output, sweat, and muscle blood flow decrease, likely leading to the symptoms seen with heat exhaustion: weakness, profound fatigue, and occasionally confusion and disorientation. Athletes with suspected heat exhaustion should be moved to a cooler area, laid down with legs elevated, and orally rehydrated. If they do not improve with oral rehydration, they may require intravenous fluids. The diagnosis of heat exhaustion hinges on a rectal temperature of <104°F; if >104°F the athlete should be presumed to have heat stroke, which will be addressed in the following paragraphs. Players can be cleared to return to play in mild cases within 24 to 48 hours with gradual increases in exercise intensity.²⁴

EXERTIONAL HEAT STROKE

EHS occurs when the body can no longer regulate the core body temperature and it rises to upwards of 104°F. In EHS, elevated core body temperature is associated with evidence of end organ dysfunction. The most easily identified on the playing field is likely central nervous system dysfunction, including irritability, confusion, irrational behavior, lethargy, dizziness, confusion, and even loss of consciousness. Temperature should be measured with rectal temperature only, as other methods of measurement have been shown to be consistently inaccurate.²² Heat stroke can be confused with exertional hyponatremia, heat exhaustion, or concussion, especially when core body temperature cannot be determined. However, EHS should always be the presumed cause of altered mentation when no rectal temperature is available because rapid cooling is critical to minimizing lasting effects. Morbidity and mortality are directly related to the length of time required to cool the athlete under 40°C (104°F).²⁴ Cooling should be completed on site prior to transport to a medical facility and is best achieved with submersion in an ice bath (ie, a kiddie pool or soaking tub full of ice and water).^22,25 If an ice bath is not available, ice bags should be applied to the neck axilla and groin and exchanged for fresh bags every 2 to 3 minutes.²² Ice bags have been shown to be inferior to whole body cooling, only cooling the athlete .04°C to .08°C/min compared to .15°C to .24°C/min with the ice bath.²⁴ All other tests should be delayed until cooling is achieved, unless they can be completed while cooling the athlete. The athlete can be removed from the ice bath once rectal temperatures reach <101°F to 102°F.²³ If the athlete returns to baseline after cooling, transportation to a medical facility may not be necessary. However, they should refrain from physical activity and heat exposure for at least 7 days and should be evaluated by a physician at that time. If all labs are normal and the athlete is asymptomatic, they can start progressive return to play under the direction of an athletic trainer or a sports medicine physician.²³

Continue to: HEAT-RELATED ILLNESS...

 

 

HEAT-RELATED ILLNESS

It is impossible to predict exactly which athletes will be most at risk for heat-related illness, so it is important to have a high degree of suspicion when environmental conditions are right. Athletes with recent illness, fever, or lack of sleep are at higher risk. Additional intrinsic risk factors include low fitness level, obesity, and inadequate hydration. Athletes who are highly competitive or motivated can be more likely to push through the early signs of illness or be reluctant to report symptoms.²³ Those with a history of exertional heat illness are more at risk for developing it again in the future.²³

The extrinsic risk factors for the development of heat-related illness are much easier to identify and modify in order to keep athletes safe. High temperature and high humidity conditions, heavy sun exposure, and exposure to similar conditions the preceding day put athletes at risk for exertional heat illness. Risks are even greater when the exercise is prolonged or intense with few breaks and access to hydration is limited.²³ Therefore, prevention of exertional heat illness is centered on these external risk factors.

Each team should have a heat policy as part of their EAP aimed at prevention and early recognition of heat-related illness. This policy should be shared with all athletes and coaches. The plan should be centered on acclimatization, activity modification, and early recognition and management as previously discussed. The US Soccer Federation “Recognize to Recover” Heat Guidelines suggest a 3-step process for appropriate activity modification:²²

1. Find the wet bulb globe temperature, either using a wet bulb globe thermometer or the temperature and humidity (Figure 1).

2. Find your regional weather category on the map (Figure 2).

3. Find your alert level and work to rest ratio recommendations (Figure 3).

Scheduled hydration breaks should be given as listed in Figure 3. Breaks of 4 minutes should be given for each 30 minutes of continuous practice or play. In a regulation 90-minute match, a hydration break should be given at 30 and 75 minutes (with half time at 45 minutes) at minimum. Athletes should be educated about where hydration can be accessed, and given unlimited access to hydration even outside of planned breaks.²²

Acclimatization to conditions is another integral part of preventing heat-related illness. It allows the body time to adapt to exercising in heat gradually, with a measured progression of exertion over the course of 10 to 14 days. The “Recognize to Recover” Heat Guidelines also provide guidance on acclimatization, and specifics can be found on the website.¹ Generally speaking, the warmest part of the day, usually between 11 AM and 4 PM, should be avoided for all training sessions, and length of practice and exertion should be gradually increased over 2 weeks.²²

In summary, appropriate acclimatization, hydration, activity modification, and education of athletes and staff are essential for the prevention of heat-related illness. Athletes and staff should understand the signs and symptoms of heat-related illness so that it can be recognized early and treated appropriately. If an athlete is altered in the heat and rectal temperature is >104°F or rectal temperature cannot be obtained, rapid cooling using an ice bath or ice bags is essential to prevent the morbidity and mortality associated with EHS. Above all, teams should have an explicit plan that includes protocols for acclimatization, activity modification, and all necessary equipment to prevent and treat heat-related illnesses should they occur, and ultimately keep athletes safe and healthy.

ABSTRACT

As one of the most popular sports in the world, soccer injury rates involving the knee continue to rise. An alarming trend of knee injuries, including increased anterior cruciate ligament ruptures, underscores the need to review our current understanding of these injuries in soccer players. This article includes a critical review of the epidemiology of knee injuries in soccer, anterior cruciate ligament and other ligamentous injuries, cartilage and meniscal injury, post-traumatic osteoarthritis, as well as current prevention initiatives.

Continue to: EPIDEMIOLOGY...

EPIDEMIOLOGY

There are currently 28 players on each of the Major League Soccer (MLS) teams, and during the 2013 to 2014 academic year, the National Federation of State High School Associations (NFHS) reported that 417,419 boys and 374,564 girls played high school soccer and the National Collegiate Athletic Association (NCAA) reported that 23,602 males and 26,358 females played collegiate soccer.⁵ As such, knee injuries in this population are a major concern for those involved in sports medicine. Several injuries occurring during soccer involve the lower extremity, particularly the knee.¹ In fact, multiple reports estimate that up to 17.6% of soccer-related injuries presenting to the emergency room involved the knee.^1,6-9 The majority of these injuries are noncontact injuries, although contact injuries do still occur.^10,11

Risk factors for injuries in soccer may be non-modifiable (such as age and gender) and modifiable (such as level of conditioning, force, balance, and flexibility). Inadequate lower motor coordination may result in injury in the adolescent population, and advanced age >28 years in males and >25 years in females is considered as a high-risk factor for injury.^12,13 Importantly, gender and age have been reported to play a significant role as risk factors for ACL injury.⁶ In fact, female players have a 3 to 5 times higher risk of significant knee injury, including ACL injuries, than male players.^4,14-16 Preventative programs such as the FIFA 11+ program have been set forth to augment conditioning as part of managing the modifiable risk factors.

Like American football, playing on artificial turf has been questioned as a contributor to injury compared to playing on natural grass.^17,18 In recent years, newer generations of artificial turf have been developed to more closely replicate the characteristics of natural grass. Meyers¹⁹ compared the incidence, mechanisms, and severity of match-related collegiate men’s soccer injuries on artificial turf and those on natural grass and demonstrated no significant difference in knee injuries between the 2 surfaces. This finding was consistent with previous studies that reported no difference in the incidence of knee injuries on either surface in women’s collegiate and elite-level soccer.^15,20,21

Continue to: ACL INJURIES...

ACL INJURIES

ACL injuries are life-changing events that can significantly affect the career of a soccer athlete. As a major stabilizer of the knee, the ACL primarily prevents anterior tibial translation with the anteromedial bundle and secondarily resists tibial rotation with the posterolateral bundle. The ligament takes origin from the posteromedial aspect of the lateral femoral condyle and inserts anterior to the tibial intercondylar eminence. Grading of ACL injuries is based on the Lachman test, which is performed between 20°and 30° of knee flexion and measures the amount of anterior tibial translation relative to the femur (A = firm endpoint, B = no endpoint; grade I: 3-5 mm, grade II (A/B): 5-10 mm, grade III (A/B): >10 mm).

ACL injury may occur via contact or noncontact mechanisms. Noncontact mechanisms of ACL injury in soccer athletes contribute to about 85% of injuries.^6,22-25 Typical noncontact mechanism of injury involves a forceful valgus collapse with the knee near full extension and combined external or internal rotation of the tibia^23,26 (Figure 1). This on-field scenario generally involves cutting and torsional movement, as well as landing after a jump, particularly in 1-legged stance. Similarly, a disturbance in balance caused by the opponent may incite a noncontact mechanism resulting in ACL rupture.^6,27 Video analyses of professional soccer players have also demonstrated a higher risk of noncontact ACL injury within the first 9 minutes of the match, with the most common playing situation resulting in injury being pressing, followed by kicking and heading.^24,25,28 Contact mechanisms resulting in ACL injury, however, are not an uncommon occurrence in soccer players with higher risk for certain positions. Brophy and colleagues²⁹ reviewed ACL injuries in professional and collegiate soccer players and reported a higher risk of ACL injury during defending and tackling. Similarly, Faude and colleagues³⁰ found the risk of injury to be higher in defenders and strikers than in goalkeepers and midfielders.

Female athletes participating in elite-level athletics, especially soccer, represent a high-risk group for ACL injury. In fact, these soccer athletes experience ACL injury at an incidence 3 times higher than that in male athletes.^31-35 Female soccer athletes may also be at risk for reinjury to the ACL and contralateral ACL injury. Female gender, in combination with participation in soccer, thus represents a high-risk group for ACL tear in athletics. Allen and colleagues³⁶ retrospectively reviewed 180 female patients who had undergone ACL reconstruction (ACLR) (90 soccer players and 90 non-soccer players) over a mean period of 68.8 months. In their series, soccer players sustained significantly more ACL injuries than non-soccer players, including graft failures (11% vs 1%) and contralateral ACL tears (17% vs 4%).

ACLR is the gold standard treatment for elite soccer athletes. A recent survey of MLS team orthopedic surgeons revealed several important details regarding decision-making in ACLR in this population. From a technical standpoint, the vast majority of surgeons used a single incision, arthroscopically assisted, single-bundle reconstruction (91%). Femoral tunnel drilling was almost equally split between transtibial (51%) and use of an accessory medial portal (46%). Bone-patella-tendon-bone (BPTB) autograft was the most preferred graft choice (68%), and quadriceps tendon autograft was the least preferred. The majority of surgeons preformed ACLR within 4 weeks and permitted return to sport (RTS) without restrictions at 6 to 8 months.³⁷

Continue to: There is a scarcity of literature regarding...

There is a scarcity of literature regarding the use of soft tissue and BPTB allografts in soccer athletes. However, one study reported no difference in patient-reported outcomes and return to preinjury level of activity (including soccer) with the use of either autograft or allograft BPTB in ACLR.³⁸ The authors’ preference was to avoid the use of allograft in elite-level soccer athletes as the reported rate of ACL re-tear was 4 to 8 times higher than that with autograft reconstruction, as shown in athletes and military personnel.^39,40 BPTB autograft and hamstring autograft (semitendinosus and/or gracilis) are common graft choices for soccer athletes. Gifstad and colleagues⁴¹ compared BPTB autograft and hamstring autograft in 45,998 primary ACLRs performed in Scandinavia. Although the cohort included, but was not limited to, soccer players, the authors reported an overall risk of revision that was significantly lower in the BPTB autograft group than in the hamstring autograft group (hazard ratio, 0.63; 95% confidence interval, 0.53-0.74).⁴¹ Mohammadi and colleagues⁴² prospectively compared the functional outcomes of 42 competitive soccer players who underwent ACLR with BPTB autograft vs those who underwent ACLR with hamstring autograft at the time of RTS. Players who had undergone ACLR with hamstring autograft demonstrated greater quadriceps torque, as well as better performance with triple-hop, crossover-hop, and jump-landing tests; however, both groups demonstrated similar hamstring torque and performance in 2 other hop tests.⁴² In the authors’ opinion, there may be a concern regarding the use of hamstring autograft in elite soccer players considering that hamstring strains are extremely common in this athletic population; however, further research would be necessary to elucidate whether this is an actual or a theoretical risk. Although not yet studied in elite-level athletes, early clinical results of ACL repair with suture augmentation show promise for certain injury patterns. These include proximal femoral ACL avulsion injuries (Sherman type 1) of excellent tissue quality that have the ability to be reapproximated to the femoral origin⁴³ (Figures 2A, 2B). In a recent series,^43-45 early clinical outcomes were found to be excellent and maintained at midterm follow-up.

In the NCAA soccer athletes, an overall RTS rate of 85% has been reported in those undergoing ACLR, with a significantly higher rate observed in scholarship versus non-scholarship athletes.⁴⁶ Howard and colleagues⁴⁶ reported median time to unrestricted game play of 6.1 months, with 75% returning to the same or higher level position on the depth chart. Among their studied collegiate soccer athletes, 32% reported continued participation in soccer on some level after college (recreational, semiprofessional, or professional).⁴⁶ RTS rates for MLS soccer players have also been reported to be high, ranging from 74% to 77%, most of them returning within the following season at 10 ± 2.8 months.^47,48 These findings were consistent with the RTS rate of 72% reported by the Multicenter Orthopaedic Outcomes Network (MOON) group, which analyzed 100 female and male soccer players undergoing ACLR at a minimum 7-year follow-up. In this series, Brophy and colleagues^29,49 reported an RTS at 12 ± 14.3 months, with 85% returning to the same or a higher level of play prior to their injury. Erickson and colleagues⁴⁷ analyzed a series of 57 ACLRs performed in MLS athletes and reported no significant difference in preinjury or postoperative performance, or between cases and uninjured controls. Arundale and colleagues⁴⁸ demonstrated no significantly increased risk of lower extremity injury in MLS athletes after ACLR, but the athletes had significantly shorter careers than their uninjured counterparts. Curiously, RTS rates for European professional soccer athletes have been reported to be substantially higher at 95% to 97%.^50,51 Although we can only speculate the reasons for such a discrepancy, the difference in RTS rates for similar athletes highlights a need for objective criteria to determine and report RTS rates, while also providing guidelines to prevent reinjury. Such a consensus among orthopedists is not yet present in the literature.

Soccer players and adolescent age in combination have been shown to portend a 3-fold increased risk of revision surgery for ACL failure in a cohort of 16,930 patients from the Swedish National Knee Ligament Register.⁵² Published data regarding ACL failure and management of revision ACLR in elite-level soccer athletes are currently lacking. However, low failure rates of 3% to 10% requiring revision reconstruction have been reported.^47,49 Arundale and colleagues⁴⁸ reported 2 incidences of players with ACL graft failures, 1 BPTB autograft and 1 BPTB allograft, both of whom were able to return to MLS after revision ACLR. It is the authors’ preference to use ipsilateral hamstring autograft or contralateral BPTB autograft when an ACL revision reconstruction is required.

Continue to: OTHER LIGAMENTOUS INJURIES...

OTHER LIGAMENTOUS INJURIES

The majority of research efforts regarding knee injuries in this population are focused on the ACL. Correspondingly, literature regarding injury to the collateral ligaments and the posterior cruciate ligament (PCL) in soccer players is sparse. The lateral collateral ligament (LCL) and the medial collateral ligament (MCL) play important roles as primary stabilizers to varus and valgus forces, respectively. The PCL is the primary posterior stabilizer of the knee, preventing posterior translation of the tibia. Injury to these structures may result in significant time lost from soccer and risk of reinjury.^53,54

The MCL is the one of the most commonly injured ligaments in sports, including soccer.^53,55 The injury mechanism generally involves contact with a resulting valgus force applied to the knee.⁵⁵ Grading of MCL injuries is based on the amount of medial joint gapping with applied valgus force during examination (grade I: <5 mm, grade II: 5-10 mm, grade III: >10 mm). Kramer and colleagues⁵³ reviewed collateral ligament injuries in the adolescent population and found that MCL injuries occurred 4 times more often than LCL injuries and about 25% were grade III injuries, most commonly occurring in American football and soccer players. Soccer also touts the highest sport-specific MCL injury rate for high school and collegiate athletics, particularly for female NCAA soccer players.⁵⁶ At the professional level, Lundblad and colleagues⁵⁵ reported 346 MCL injuries in 27 European teams over an 11-year period, of which 70% were contact-related, and the average time-off from soccer was 28 days.

Most surgeons treat isolated MCL injuries nonoperatively, regardless of grade.^57,58 This includes activity modification, use of a hinged knee brace, quadriceps strengthening, and progressive return to play. The literature currently lacks substantial data to guide MCL injury management, specifically in elite soccer athletes. In our experience, grade I injuries are managed nonoperatively and RTS is allowed at 4 to 6 weeks. Grade II injuries are also managed nonoperatively and RTS is allowed at 6 to 8 weeks. Grade III injuries are generally allowed RTS at 8 to 12 weeks and may be considered for surgery in the context of concomitant injuries (eg, posteromedial capsular injury, multiligamentous knee injuries, and meniscal injuries). In some athletes, we consider using a varus unloader brace to help maximize decreased stress on the MCL while still allowing the athlete to be fully weight-bearing. We have found it less ideal to limit weight-bearing in elite athletes, which may negatively affect overall lower extremity neuromuscular proprioception and potentially prolong a safe return to play. Some athletes may experience prolonged soreness at the MCL femoral or tibial attachment despite being able to return to play. It is important to counsel athletes about these prolonged symptoms to set expectations, as this may even occur with grade I MCL injuries. Other rare instances where surgical management may be indicated include persistent pain and instability following nonoperative treatment of grade III injuries and highly displaced tibial avulsions of the ligament resulting in poor healing.^59,60

Data regarding LCL injuries in soccer are extremely sparse. In our experience, treatment and RTS rates for isolated LCL injuries are similar to those for MCL injuries. However, it is worth noting that one-quarter of LCL injuries may occur in combination with injury to other posterolateral corner structures.⁵³

PCL injuries are more commonly associated with vehicular trauma but have also been reported to occur in sports at a rate of 33% to 40%.^61,62 The mechanism of injury in athletes generally involves a fall onto the hyperflexed knee with the foot in plantarflexion or a direct blow to the anterior tibia in a flexed knee.^62,63 Classification of PCL injuries is based on posterior translation of the tibia relative to the femur with the knee flexed to 90°(grade I: 1-5 mm, grade II: 6-10 mm, grade III: >10 mm). In one cohort of 62 patients with isolated PCL injuries, soccer was found to be among the top 5 causes of injury.⁶⁴ A Scandinavian review of 1287 patients who underwent PCL reconstruction found soccer to be the sport with the highest number of injuries (13.1%).⁶⁵ The goalkeeper was most commonly subjected to this injury.⁶² Krutsch and colleagues⁵⁴ compared PCL injuries in new, professional soccer players to those in players at the closest amateur level of play. In their series, 90% of PCL injuries occurred during preseason in players who were at a lower level of play in the previous season. This finding suggested that a rapid increase in training and playing intensity may have been a significant risk factor for PCL injury. Substantial literature supporting nonoperative or operative management of PCL injuries in soccer athletes is currently lacking. Historically, nonoperative treatment has been the initial management for isolated PCL injuries; however, surgical intervention has become increasingly used for both isolated and combined PCL injuries.⁶⁶

Continue to: CARTILAGE AND MENISCAL INJURIES...

CARTILAGE AND MENISCAL INJURIES

The prevalence of osteoarthritis (OA) in retired soccer players is high.^67,68 Articular cartilage degeneration with subsequent OA occurs in up to 32% of soccer players and ultimately leads to significant disability and retirement from the sport. High physical demands and concomitant knee injuries probably predispose to the development of posttraumatic OA.^69-71

Several techniques addressing cartilage débridement or restoration have been reported, with successful RTS but with variable durability.^72-75 Recently, Andrade and colleagues⁷⁶ performed a systematic review of 217 articular cartilage defects in soccer players that were treated using restoration techniques, including chondroplasty, microfracture, autologous chondrocyte implantation (ACI), and osteochondral autograft. Although no superior technique could be ascertained, microfracture and osteochondral autograft procedures led to the quickest return to play, and ACI techniques enhanced long-standing clinical and functional results.⁷⁶ More recently, osteochondral allograft transplantation has also been described with an 84% return to some level of activity (including soccer) and 60% of athletes returning to high-level sports participation at a mean follow-up of 4.5 years⁷⁷ (Figures 3A-3C). Although chondroplasty may be successful and allow for a quicker return to play in some soccer players (return to play from 6-12 weeks), the authors believe that a strong cartilage scaffold repair strategy with early weight-bearing, including osteochondral autograft and allograft procedures (return to play from 6-9 months), must also be considered in focal chondral defects to optimize both short-term and potential long-term success.

Meniscal injuries are also prevalent in the soccer population, and consistent with ACL injuries, female players are at least twice as likely to sustain a meniscal tear.^78,79 Meniscal damage can occur in isolation or in association with ACL rupture. Repair techniques should be strongly considered as chondral changes in the setting of meniscal deficiency are a significant short- and long-term concern for elite athletes. However, due to intrinsically poor healing potential, partial meniscectomy is unfortunately more often performed.^79,80 In either case, meniscal deficiency is recognized as a precursor to the development of OA as meniscal functionality is lost and the articular cartilage is subjected to increased biomechanical loading.^81,82 Nawabi and colleagues⁸³ analyzed RTS in 90 professional soccer players following partial meniscectomy. Median RTS was at 7 weeks for lateral meniscectomies and at 5 weeks for medial meniscectomies. RTS probability was 5.99 times greater after medial meniscectomy at all time points. Lateral meniscectomies were associated with an increased risk of postoperative adverse events, reoperation, and a significantly lower rate of return to play.⁸³ In the case of severe meniscal deficiency, particularly post-meniscectomy, meniscal allograft transplantation (MAT) may be considered. In a series of MATs in lower division Spanish players, 12/14 (85.7%) returned to play at an average of 7.6 months.⁸⁴ A more recent series of professional players reported 9/12 (75%) RTS as professionals and 2/12 (17%) as semiprofessionals at an average of 10.5 months.⁸⁵ The authors’ strong preference is to perform meniscus-saving procedures whenever possible. Due to the longer recovery and return to play associated with meniscus repair than partial meniscectomy, most of the soccer players will often prefer to proceed with partial meniscectomy. Despite the ultimate treatment, it is critical that the surgeon and the soccer player have an in-depth conversation concerning the risks and benefits for each procedure and individualize treatment to the individual soccer player accordingly.

Continue to: INJURY PREVENTION...

INJURY PREVENTION

Given the breadth and the prevalence of soccer-related injuries, the FIFA11+ program was developed in 2006 as an injury prevention measure (Figure 4). The warm-up program includes 15 structured exercises emphasizing core stabilization, thigh muscle training, proprioception, dynamic stabilization, and plyometric exercises. The routine is believed to be easily executed and effective at preventing the incidence of noncontact injuries.^86,87 Recently, Sadigursky and colleagues¹ performed a systematic review of randomized clinical trials examining the efficacy of FIFA11+. The authors reported a reduction in injuries by 30% and a relative risk of 0.70 for lower limb injuries, highlighting the significant preventative importance of the program.¹ Post-training programs may also be beneficial as it has been shown that performing FIFA11+ both before and after training reduced overall injury rates in male, amateur soccer players.⁸⁸ Regardless of the prevention program, it is critical that every league, team, medical team, and athlete have a thorough injury prevention strategy to help keep players healthy and not wait until they have instead sustained a significant injury.

CONCLUSION

Knee injuries are common in soccer, with an alarming number of ACL injuries, as well as other significant pathology. Understanding the unique epidemiology, risk factors, treatment, and injury prevention strategies is critically important in helping medical professionals provide care for all levels of elite soccer players.

ABSTRACT

As one of the most popular sports in the world, soccer injury rates involving the knee continue to rise. An alarming trend of knee injuries, including increased anterior cruciate ligament ruptures, underscores the need to review our current understanding of these injuries in soccer players. This article includes a critical review of the epidemiology of knee injuries in soccer, anterior cruciate ligament and other ligamentous injuries, cartilage and meniscal injury, post-traumatic osteoarthritis, as well as current prevention initiatives.

Continue to: EPIDEMIOLOGY...

EPIDEMIOLOGY

There are currently 28 players on each of the Major League Soccer (MLS) teams, and during the 2013 to 2014 academic year, the National Federation of State High School Associations (NFHS) reported that 417,419 boys and 374,564 girls played high school soccer and the National Collegiate Athletic Association (NCAA) reported that 23,602 males and 26,358 females played collegiate soccer.⁵ As such, knee injuries in this population are a major concern for those involved in sports medicine. Several injuries occurring during soccer involve the lower extremity, particularly the knee.¹ In fact, multiple reports estimate that up to 17.6% of soccer-related injuries presenting to the emergency room involved the knee.^1,6-9 The majority of these injuries are noncontact injuries, although contact injuries do still occur.^10,11

Risk factors for injuries in soccer may be non-modifiable (such as age and gender) and modifiable (such as level of conditioning, force, balance, and flexibility). Inadequate lower motor coordination may result in injury in the adolescent population, and advanced age >28 years in males and >25 years in females is considered as a high-risk factor for injury.^12,13 Importantly, gender and age have been reported to play a significant role as risk factors for ACL injury.⁶ In fact, female players have a 3 to 5 times higher risk of significant knee injury, including ACL injuries, than male players.^4,14-16 Preventative programs such as the FIFA 11+ program have been set forth to augment conditioning as part of managing the modifiable risk factors.

Like American football, playing on artificial turf has been questioned as a contributor to injury compared to playing on natural grass.^17,18 In recent years, newer generations of artificial turf have been developed to more closely replicate the characteristics of natural grass. Meyers¹⁹ compared the incidence, mechanisms, and severity of match-related collegiate men’s soccer injuries on artificial turf and those on natural grass and demonstrated no significant difference in knee injuries between the 2 surfaces. This finding was consistent with previous studies that reported no difference in the incidence of knee injuries on either surface in women’s collegiate and elite-level soccer.^15,20,21

Continue to: ACL INJURIES...

ACL INJURIES

ACL injuries are life-changing events that can significantly affect the career of a soccer athlete. As a major stabilizer of the knee, the ACL primarily prevents anterior tibial translation with the anteromedial bundle and secondarily resists tibial rotation with the posterolateral bundle. The ligament takes origin from the posteromedial aspect of the lateral femoral condyle and inserts anterior to the tibial intercondylar eminence. Grading of ACL injuries is based on the Lachman test, which is performed between 20°and 30° of knee flexion and measures the amount of anterior tibial translation relative to the femur (A = firm endpoint, B = no endpoint; grade I: 3-5 mm, grade II (A/B): 5-10 mm, grade III (A/B): >10 mm).

ACL injury may occur via contact or noncontact mechanisms. Noncontact mechanisms of ACL injury in soccer athletes contribute to about 85% of injuries.^6,22-25 Typical noncontact mechanism of injury involves a forceful valgus collapse with the knee near full extension and combined external or internal rotation of the tibia^23,26 (Figure 1). This on-field scenario generally involves cutting and torsional movement, as well as landing after a jump, particularly in 1-legged stance. Similarly, a disturbance in balance caused by the opponent may incite a noncontact mechanism resulting in ACL rupture.^6,27 Video analyses of professional soccer players have also demonstrated a higher risk of noncontact ACL injury within the first 9 minutes of the match, with the most common playing situation resulting in injury being pressing, followed by kicking and heading.^24,25,28 Contact mechanisms resulting in ACL injury, however, are not an uncommon occurrence in soccer players with higher risk for certain positions. Brophy and colleagues²⁹ reviewed ACL injuries in professional and collegiate soccer players and reported a higher risk of ACL injury during defending and tackling. Similarly, Faude and colleagues³⁰ found the risk of injury to be higher in defenders and strikers than in goalkeepers and midfielders.

Female athletes participating in elite-level athletics, especially soccer, represent a high-risk group for ACL injury. In fact, these soccer athletes experience ACL injury at an incidence 3 times higher than that in male athletes.^31-35 Female soccer athletes may also be at risk for reinjury to the ACL and contralateral ACL injury. Female gender, in combination with participation in soccer, thus represents a high-risk group for ACL tear in athletics. Allen and colleagues³⁶ retrospectively reviewed 180 female patients who had undergone ACL reconstruction (ACLR) (90 soccer players and 90 non-soccer players) over a mean period of 68.8 months. In their series, soccer players sustained significantly more ACL injuries than non-soccer players, including graft failures (11% vs 1%) and contralateral ACL tears (17% vs 4%).

ACLR is the gold standard treatment for elite soccer athletes. A recent survey of MLS team orthopedic surgeons revealed several important details regarding decision-making in ACLR in this population. From a technical standpoint, the vast majority of surgeons used a single incision, arthroscopically assisted, single-bundle reconstruction (91%). Femoral tunnel drilling was almost equally split between transtibial (51%) and use of an accessory medial portal (46%). Bone-patella-tendon-bone (BPTB) autograft was the most preferred graft choice (68%), and quadriceps tendon autograft was the least preferred. The majority of surgeons preformed ACLR within 4 weeks and permitted return to sport (RTS) without restrictions at 6 to 8 months.³⁷

Continue to: There is a scarcity of literature regarding...

There is a scarcity of literature regarding the use of soft tissue and BPTB allografts in soccer athletes. However, one study reported no difference in patient-reported outcomes and return to preinjury level of activity (including soccer) with the use of either autograft or allograft BPTB in ACLR.³⁸ The authors’ preference was to avoid the use of allograft in elite-level soccer athletes as the reported rate of ACL re-tear was 4 to 8 times higher than that with autograft reconstruction, as shown in athletes and military personnel.^39,40 BPTB autograft and hamstring autograft (semitendinosus and/or gracilis) are common graft choices for soccer athletes. Gifstad and colleagues⁴¹ compared BPTB autograft and hamstring autograft in 45,998 primary ACLRs performed in Scandinavia. Although the cohort included, but was not limited to, soccer players, the authors reported an overall risk of revision that was significantly lower in the BPTB autograft group than in the hamstring autograft group (hazard ratio, 0.63; 95% confidence interval, 0.53-0.74).⁴¹ Mohammadi and colleagues⁴² prospectively compared the functional outcomes of 42 competitive soccer players who underwent ACLR with BPTB autograft vs those who underwent ACLR with hamstring autograft at the time of RTS. Players who had undergone ACLR with hamstring autograft demonstrated greater quadriceps torque, as well as better performance with triple-hop, crossover-hop, and jump-landing tests; however, both groups demonstrated similar hamstring torque and performance in 2 other hop tests.⁴² In the authors’ opinion, there may be a concern regarding the use of hamstring autograft in elite soccer players considering that hamstring strains are extremely common in this athletic population; however, further research would be necessary to elucidate whether this is an actual or a theoretical risk. Although not yet studied in elite-level athletes, early clinical results of ACL repair with suture augmentation show promise for certain injury patterns. These include proximal femoral ACL avulsion injuries (Sherman type 1) of excellent tissue quality that have the ability to be reapproximated to the femoral origin⁴³ (Figures 2A, 2B). In a recent series,^43-45 early clinical outcomes were found to be excellent and maintained at midterm follow-up.

In the NCAA soccer athletes, an overall RTS rate of 85% has been reported in those undergoing ACLR, with a significantly higher rate observed in scholarship versus non-scholarship athletes.⁴⁶ Howard and colleagues⁴⁶ reported median time to unrestricted game play of 6.1 months, with 75% returning to the same or higher level position on the depth chart. Among their studied collegiate soccer athletes, 32% reported continued participation in soccer on some level after college (recreational, semiprofessional, or professional).⁴⁶ RTS rates for MLS soccer players have also been reported to be high, ranging from 74% to 77%, most of them returning within the following season at 10 ± 2.8 months.^47,48 These findings were consistent with the RTS rate of 72% reported by the Multicenter Orthopaedic Outcomes Network (MOON) group, which analyzed 100 female and male soccer players undergoing ACLR at a minimum 7-year follow-up. In this series, Brophy and colleagues^29,49 reported an RTS at 12 ± 14.3 months, with 85% returning to the same or a higher level of play prior to their injury. Erickson and colleagues⁴⁷ analyzed a series of 57 ACLRs performed in MLS athletes and reported no significant difference in preinjury or postoperative performance, or between cases and uninjured controls. Arundale and colleagues⁴⁸ demonstrated no significantly increased risk of lower extremity injury in MLS athletes after ACLR, but the athletes had significantly shorter careers than their uninjured counterparts. Curiously, RTS rates for European professional soccer athletes have been reported to be substantially higher at 95% to 97%.^50,51 Although we can only speculate the reasons for such a discrepancy, the difference in RTS rates for similar athletes highlights a need for objective criteria to determine and report RTS rates, while also providing guidelines to prevent reinjury. Such a consensus among orthopedists is not yet present in the literature.

Soccer players and adolescent age in combination have been shown to portend a 3-fold increased risk of revision surgery for ACL failure in a cohort of 16,930 patients from the Swedish National Knee Ligament Register.⁵² Published data regarding ACL failure and management of revision ACLR in elite-level soccer athletes are currently lacking. However, low failure rates of 3% to 10% requiring revision reconstruction have been reported.^47,49 Arundale and colleagues⁴⁸ reported 2 incidences of players with ACL graft failures, 1 BPTB autograft and 1 BPTB allograft, both of whom were able to return to MLS after revision ACLR. It is the authors’ preference to use ipsilateral hamstring autograft or contralateral BPTB autograft when an ACL revision reconstruction is required.

Continue to: OTHER LIGAMENTOUS INJURIES...

OTHER LIGAMENTOUS INJURIES

The majority of research efforts regarding knee injuries in this population are focused on the ACL. Correspondingly, literature regarding injury to the collateral ligaments and the posterior cruciate ligament (PCL) in soccer players is sparse. The lateral collateral ligament (LCL) and the medial collateral ligament (MCL) play important roles as primary stabilizers to varus and valgus forces, respectively. The PCL is the primary posterior stabilizer of the knee, preventing posterior translation of the tibia. Injury to these structures may result in significant time lost from soccer and risk of reinjury.^53,54

The MCL is the one of the most commonly injured ligaments in sports, including soccer.^53,55 The injury mechanism generally involves contact with a resulting valgus force applied to the knee.⁵⁵ Grading of MCL injuries is based on the amount of medial joint gapping with applied valgus force during examination (grade I: <5 mm, grade II: 5-10 mm, grade III: >10 mm). Kramer and colleagues⁵³ reviewed collateral ligament injuries in the adolescent population and found that MCL injuries occurred 4 times more often than LCL injuries and about 25% were grade III injuries, most commonly occurring in American football and soccer players. Soccer also touts the highest sport-specific MCL injury rate for high school and collegiate athletics, particularly for female NCAA soccer players.⁵⁶ At the professional level, Lundblad and colleagues⁵⁵ reported 346 MCL injuries in 27 European teams over an 11-year period, of which 70% were contact-related, and the average time-off from soccer was 28 days.

Most surgeons treat isolated MCL injuries nonoperatively, regardless of grade.^57,58 This includes activity modification, use of a hinged knee brace, quadriceps strengthening, and progressive return to play. The literature currently lacks substantial data to guide MCL injury management, specifically in elite soccer athletes. In our experience, grade I injuries are managed nonoperatively and RTS is allowed at 4 to 6 weeks. Grade II injuries are also managed nonoperatively and RTS is allowed at 6 to 8 weeks. Grade III injuries are generally allowed RTS at 8 to 12 weeks and may be considered for surgery in the context of concomitant injuries (eg, posteromedial capsular injury, multiligamentous knee injuries, and meniscal injuries). In some athletes, we consider using a varus unloader brace to help maximize decreased stress on the MCL while still allowing the athlete to be fully weight-bearing. We have found it less ideal to limit weight-bearing in elite athletes, which may negatively affect overall lower extremity neuromuscular proprioception and potentially prolong a safe return to play. Some athletes may experience prolonged soreness at the MCL femoral or tibial attachment despite being able to return to play. It is important to counsel athletes about these prolonged symptoms to set expectations, as this may even occur with grade I MCL injuries. Other rare instances where surgical management may be indicated include persistent pain and instability following nonoperative treatment of grade III injuries and highly displaced tibial avulsions of the ligament resulting in poor healing.^59,60

Data regarding LCL injuries in soccer are extremely sparse. In our experience, treatment and RTS rates for isolated LCL injuries are similar to those for MCL injuries. However, it is worth noting that one-quarter of LCL injuries may occur in combination with injury to other posterolateral corner structures.⁵³

PCL injuries are more commonly associated with vehicular trauma but have also been reported to occur in sports at a rate of 33% to 40%.^61,62 The mechanism of injury in athletes generally involves a fall onto the hyperflexed knee with the foot in plantarflexion or a direct blow to the anterior tibia in a flexed knee.^62,63 Classification of PCL injuries is based on posterior translation of the tibia relative to the femur with the knee flexed to 90°(grade I: 1-5 mm, grade II: 6-10 mm, grade III: >10 mm). In one cohort of 62 patients with isolated PCL injuries, soccer was found to be among the top 5 causes of injury.⁶⁴ A Scandinavian review of 1287 patients who underwent PCL reconstruction found soccer to be the sport with the highest number of injuries (13.1%).⁶⁵ The goalkeeper was most commonly subjected to this injury.⁶² Krutsch and colleagues⁵⁴ compared PCL injuries in new, professional soccer players to those in players at the closest amateur level of play. In their series, 90% of PCL injuries occurred during preseason in players who were at a lower level of play in the previous season. This finding suggested that a rapid increase in training and playing intensity may have been a significant risk factor for PCL injury. Substantial literature supporting nonoperative or operative management of PCL injuries in soccer athletes is currently lacking. Historically, nonoperative treatment has been the initial management for isolated PCL injuries; however, surgical intervention has become increasingly used for both isolated and combined PCL injuries.⁶⁶

Continue to: CARTILAGE AND MENISCAL INJURIES...

CARTILAGE AND MENISCAL INJURIES

The prevalence of osteoarthritis (OA) in retired soccer players is high.^67,68 Articular cartilage degeneration with subsequent OA occurs in up to 32% of soccer players and ultimately leads to significant disability and retirement from the sport. High physical demands and concomitant knee injuries probably predispose to the development of posttraumatic OA.^69-71

Several techniques addressing cartilage débridement or restoration have been reported, with successful RTS but with variable durability.^72-75 Recently, Andrade and colleagues⁷⁶ performed a systematic review of 217 articular cartilage defects in soccer players that were treated using restoration techniques, including chondroplasty, microfracture, autologous chondrocyte implantation (ACI), and osteochondral autograft. Although no superior technique could be ascertained, microfracture and osteochondral autograft procedures led to the quickest return to play, and ACI techniques enhanced long-standing clinical and functional results.⁷⁶ More recently, osteochondral allograft transplantation has also been described with an 84% return to some level of activity (including soccer) and 60% of athletes returning to high-level sports participation at a mean follow-up of 4.5 years⁷⁷ (Figures 3A-3C). Although chondroplasty may be successful and allow for a quicker return to play in some soccer players (return to play from 6-12 weeks), the authors believe that a strong cartilage scaffold repair strategy with early weight-bearing, including osteochondral autograft and allograft procedures (return to play from 6-9 months), must also be considered in focal chondral defects to optimize both short-term and potential long-term success.

Meniscal injuries are also prevalent in the soccer population, and consistent with ACL injuries, female players are at least twice as likely to sustain a meniscal tear.^78,79 Meniscal damage can occur in isolation or in association with ACL rupture. Repair techniques should be strongly considered as chondral changes in the setting of meniscal deficiency are a significant short- and long-term concern for elite athletes. However, due to intrinsically poor healing potential, partial meniscectomy is unfortunately more often performed.^79,80 In either case, meniscal deficiency is recognized as a precursor to the development of OA as meniscal functionality is lost and the articular cartilage is subjected to increased biomechanical loading.^81,82 Nawabi and colleagues⁸³ analyzed RTS in 90 professional soccer players following partial meniscectomy. Median RTS was at 7 weeks for lateral meniscectomies and at 5 weeks for medial meniscectomies. RTS probability was 5.99 times greater after medial meniscectomy at all time points. Lateral meniscectomies were associated with an increased risk of postoperative adverse events, reoperation, and a significantly lower rate of return to play.⁸³ In the case of severe meniscal deficiency, particularly post-meniscectomy, meniscal allograft transplantation (MAT) may be considered. In a series of MATs in lower division Spanish players, 12/14 (85.7%) returned to play at an average of 7.6 months.⁸⁴ A more recent series of professional players reported 9/12 (75%) RTS as professionals and 2/12 (17%) as semiprofessionals at an average of 10.5 months.⁸⁵ The authors’ strong preference is to perform meniscus-saving procedures whenever possible. Due to the longer recovery and return to play associated with meniscus repair than partial meniscectomy, most of the soccer players will often prefer to proceed with partial meniscectomy. Despite the ultimate treatment, it is critical that the surgeon and the soccer player have an in-depth conversation concerning the risks and benefits for each procedure and individualize treatment to the individual soccer player accordingly.

Continue to: INJURY PREVENTION...

INJURY PREVENTION

Given the breadth and the prevalence of soccer-related injuries, the FIFA11+ program was developed in 2006 as an injury prevention measure (Figure 4). The warm-up program includes 15 structured exercises emphasizing core stabilization, thigh muscle training, proprioception, dynamic stabilization, and plyometric exercises. The routine is believed to be easily executed and effective at preventing the incidence of noncontact injuries.^86,87 Recently, Sadigursky and colleagues¹ performed a systematic review of randomized clinical trials examining the efficacy of FIFA11+. The authors reported a reduction in injuries by 30% and a relative risk of 0.70 for lower limb injuries, highlighting the significant preventative importance of the program.¹ Post-training programs may also be beneficial as it has been shown that performing FIFA11+ both before and after training reduced overall injury rates in male, amateur soccer players.⁸⁸ Regardless of the prevention program, it is critical that every league, team, medical team, and athlete have a thorough injury prevention strategy to help keep players healthy and not wait until they have instead sustained a significant injury.

CONCLUSION

Knee injuries are common in soccer, with an alarming number of ACL injuries, as well as other significant pathology. Understanding the unique epidemiology, risk factors, treatment, and injury prevention strategies is critically important in helping medical professionals provide care for all levels of elite soccer players.

ABSTRACT

As one of the most popular sports in the world, soccer injury rates involving the knee continue to rise. An alarming trend of knee injuries, including increased anterior cruciate ligament ruptures, underscores the need to review our current understanding of these injuries in soccer players. This article includes a critical review of the epidemiology of knee injuries in soccer, anterior cruciate ligament and other ligamentous injuries, cartilage and meniscal injury, post-traumatic osteoarthritis, as well as current prevention initiatives.

Continue to: EPIDEMIOLOGY...

EPIDEMIOLOGY

There are currently 28 players on each of the Major League Soccer (MLS) teams, and during the 2013 to 2014 academic year, the National Federation of State High School Associations (NFHS) reported that 417,419 boys and 374,564 girls played high school soccer and the National Collegiate Athletic Association (NCAA) reported that 23,602 males and 26,358 females played collegiate soccer.⁵ As such, knee injuries in this population are a major concern for those involved in sports medicine. Several injuries occurring during soccer involve the lower extremity, particularly the knee.¹ In fact, multiple reports estimate that up to 17.6% of soccer-related injuries presenting to the emergency room involved the knee.^1,6-9 The majority of these injuries are noncontact injuries, although contact injuries do still occur.^10,11

Risk factors for injuries in soccer may be non-modifiable (such as age and gender) and modifiable (such as level of conditioning, force, balance, and flexibility). Inadequate lower motor coordination may result in injury in the adolescent population, and advanced age >28 years in males and >25 years in females is considered as a high-risk factor for injury.^12,13 Importantly, gender and age have been reported to play a significant role as risk factors for ACL injury.⁶ In fact, female players have a 3 to 5 times higher risk of significant knee injury, including ACL injuries, than male players.^4,14-16 Preventative programs such as the FIFA 11+ program have been set forth to augment conditioning as part of managing the modifiable risk factors.

Like American football, playing on artificial turf has been questioned as a contributor to injury compared to playing on natural grass.^17,18 In recent years, newer generations of artificial turf have been developed to more closely replicate the characteristics of natural grass. Meyers¹⁹ compared the incidence, mechanisms, and severity of match-related collegiate men’s soccer injuries on artificial turf and those on natural grass and demonstrated no significant difference in knee injuries between the 2 surfaces. This finding was consistent with previous studies that reported no difference in the incidence of knee injuries on either surface in women’s collegiate and elite-level soccer.^15,20,21

Continue to: ACL INJURIES...

ACL INJURIES

ACL injuries are life-changing events that can significantly affect the career of a soccer athlete. As a major stabilizer of the knee, the ACL primarily prevents anterior tibial translation with the anteromedial bundle and secondarily resists tibial rotation with the posterolateral bundle. The ligament takes origin from the posteromedial aspect of the lateral femoral condyle and inserts anterior to the tibial intercondylar eminence. Grading of ACL injuries is based on the Lachman test, which is performed between 20°and 30° of knee flexion and measures the amount of anterior tibial translation relative to the femur (A = firm endpoint, B = no endpoint; grade I: 3-5 mm, grade II (A/B): 5-10 mm, grade III (A/B): >10 mm).

ACL injury may occur via contact or noncontact mechanisms. Noncontact mechanisms of ACL injury in soccer athletes contribute to about 85% of injuries.^6,22-25 Typical noncontact mechanism of injury involves a forceful valgus collapse with the knee near full extension and combined external or internal rotation of the tibia^23,26 (Figure 1). This on-field scenario generally involves cutting and torsional movement, as well as landing after a jump, particularly in 1-legged stance. Similarly, a disturbance in balance caused by the opponent may incite a noncontact mechanism resulting in ACL rupture.^6,27 Video analyses of professional soccer players have also demonstrated a higher risk of noncontact ACL injury within the first 9 minutes of the match, with the most common playing situation resulting in injury being pressing, followed by kicking and heading.^24,25,28 Contact mechanisms resulting in ACL injury, however, are not an uncommon occurrence in soccer players with higher risk for certain positions. Brophy and colleagues²⁹ reviewed ACL injuries in professional and collegiate soccer players and reported a higher risk of ACL injury during defending and tackling. Similarly, Faude and colleagues³⁰ found the risk of injury to be higher in defenders and strikers than in goalkeepers and midfielders.

Female athletes participating in elite-level athletics, especially soccer, represent a high-risk group for ACL injury. In fact, these soccer athletes experience ACL injury at an incidence 3 times higher than that in male athletes.^31-35 Female soccer athletes may also be at risk for reinjury to the ACL and contralateral ACL injury. Female gender, in combination with participation in soccer, thus represents a high-risk group for ACL tear in athletics. Allen and colleagues³⁶ retrospectively reviewed 180 female patients who had undergone ACL reconstruction (ACLR) (90 soccer players and 90 non-soccer players) over a mean period of 68.8 months. In their series, soccer players sustained significantly more ACL injuries than non-soccer players, including graft failures (11% vs 1%) and contralateral ACL tears (17% vs 4%).

ACLR is the gold standard treatment for elite soccer athletes. A recent survey of MLS team orthopedic surgeons revealed several important details regarding decision-making in ACLR in this population. From a technical standpoint, the vast majority of surgeons used a single incision, arthroscopically assisted, single-bundle reconstruction (91%). Femoral tunnel drilling was almost equally split between transtibial (51%) and use of an accessory medial portal (46%). Bone-patella-tendon-bone (BPTB) autograft was the most preferred graft choice (68%), and quadriceps tendon autograft was the least preferred. The majority of surgeons preformed ACLR within 4 weeks and permitted return to sport (RTS) without restrictions at 6 to 8 months.³⁷

Continue to: There is a scarcity of literature regarding...

There is a scarcity of literature regarding the use of soft tissue and BPTB allografts in soccer athletes. However, one study reported no difference in patient-reported outcomes and return to preinjury level of activity (including soccer) with the use of either autograft or allograft BPTB in ACLR.³⁸ The authors’ preference was to avoid the use of allograft in elite-level soccer athletes as the reported rate of ACL re-tear was 4 to 8 times higher than that with autograft reconstruction, as shown in athletes and military personnel.^39,40 BPTB autograft and hamstring autograft (semitendinosus and/or gracilis) are common graft choices for soccer athletes. Gifstad and colleagues⁴¹ compared BPTB autograft and hamstring autograft in 45,998 primary ACLRs performed in Scandinavia. Although the cohort included, but was not limited to, soccer players, the authors reported an overall risk of revision that was significantly lower in the BPTB autograft group than in the hamstring autograft group (hazard ratio, 0.63; 95% confidence interval, 0.53-0.74).⁴¹ Mohammadi and colleagues⁴² prospectively compared the functional outcomes of 42 competitive soccer players who underwent ACLR with BPTB autograft vs those who underwent ACLR with hamstring autograft at the time of RTS. Players who had undergone ACLR with hamstring autograft demonstrated greater quadriceps torque, as well as better performance with triple-hop, crossover-hop, and jump-landing tests; however, both groups demonstrated similar hamstring torque and performance in 2 other hop tests.⁴² In the authors’ opinion, there may be a concern regarding the use of hamstring autograft in elite soccer players considering that hamstring strains are extremely common in this athletic population; however, further research would be necessary to elucidate whether this is an actual or a theoretical risk. Although not yet studied in elite-level athletes, early clinical results of ACL repair with suture augmentation show promise for certain injury patterns. These include proximal femoral ACL avulsion injuries (Sherman type 1) of excellent tissue quality that have the ability to be reapproximated to the femoral origin⁴³ (Figures 2A, 2B). In a recent series,^43-45 early clinical outcomes were found to be excellent and maintained at midterm follow-up.

In the NCAA soccer athletes, an overall RTS rate of 85% has been reported in those undergoing ACLR, with a significantly higher rate observed in scholarship versus non-scholarship athletes.⁴⁶ Howard and colleagues⁴⁶ reported median time to unrestricted game play of 6.1 months, with 75% returning to the same or higher level position on the depth chart. Among their studied collegiate soccer athletes, 32% reported continued participation in soccer on some level after college (recreational, semiprofessional, or professional).⁴⁶ RTS rates for MLS soccer players have also been reported to be high, ranging from 74% to 77%, most of them returning within the following season at 10 ± 2.8 months.^47,48 These findings were consistent with the RTS rate of 72% reported by the Multicenter Orthopaedic Outcomes Network (MOON) group, which analyzed 100 female and male soccer players undergoing ACLR at a minimum 7-year follow-up. In this series, Brophy and colleagues^29,49 reported an RTS at 12 ± 14.3 months, with 85% returning to the same or a higher level of play prior to their injury. Erickson and colleagues⁴⁷ analyzed a series of 57 ACLRs performed in MLS athletes and reported no significant difference in preinjury or postoperative performance, or between cases and uninjured controls. Arundale and colleagues⁴⁸ demonstrated no significantly increased risk of lower extremity injury in MLS athletes after ACLR, but the athletes had significantly shorter careers than their uninjured counterparts. Curiously, RTS rates for European professional soccer athletes have been reported to be substantially higher at 95% to 97%.^50,51 Although we can only speculate the reasons for such a discrepancy, the difference in RTS rates for similar athletes highlights a need for objective criteria to determine and report RTS rates, while also providing guidelines to prevent reinjury. Such a consensus among orthopedists is not yet present in the literature.

Soccer players and adolescent age in combination have been shown to portend a 3-fold increased risk of revision surgery for ACL failure in a cohort of 16,930 patients from the Swedish National Knee Ligament Register.⁵² Published data regarding ACL failure and management of revision ACLR in elite-level soccer athletes are currently lacking. However, low failure rates of 3% to 10% requiring revision reconstruction have been reported.^47,49 Arundale and colleagues⁴⁸ reported 2 incidences of players with ACL graft failures, 1 BPTB autograft and 1 BPTB allograft, both of whom were able to return to MLS after revision ACLR. It is the authors’ preference to use ipsilateral hamstring autograft or contralateral BPTB autograft when an ACL revision reconstruction is required.

Continue to: OTHER LIGAMENTOUS INJURIES...

OTHER LIGAMENTOUS INJURIES

The majority of research efforts regarding knee injuries in this population are focused on the ACL. Correspondingly, literature regarding injury to the collateral ligaments and the posterior cruciate ligament (PCL) in soccer players is sparse. The lateral collateral ligament (LCL) and the medial collateral ligament (MCL) play important roles as primary stabilizers to varus and valgus forces, respectively. The PCL is the primary posterior stabilizer of the knee, preventing posterior translation of the tibia. Injury to these structures may result in significant time lost from soccer and risk of reinjury.^53,54

The MCL is the one of the most commonly injured ligaments in sports, including soccer.^53,55 The injury mechanism generally involves contact with a resulting valgus force applied to the knee.⁵⁵ Grading of MCL injuries is based on the amount of medial joint gapping with applied valgus force during examination (grade I: <5 mm, grade II: 5-10 mm, grade III: >10 mm). Kramer and colleagues⁵³ reviewed collateral ligament injuries in the adolescent population and found that MCL injuries occurred 4 times more often than LCL injuries and about 25% were grade III injuries, most commonly occurring in American football and soccer players. Soccer also touts the highest sport-specific MCL injury rate for high school and collegiate athletics, particularly for female NCAA soccer players.⁵⁶ At the professional level, Lundblad and colleagues⁵⁵ reported 346 MCL injuries in 27 European teams over an 11-year period, of which 70% were contact-related, and the average time-off from soccer was 28 days.

Most surgeons treat isolated MCL injuries nonoperatively, regardless of grade.^57,58 This includes activity modification, use of a hinged knee brace, quadriceps strengthening, and progressive return to play. The literature currently lacks substantial data to guide MCL injury management, specifically in elite soccer athletes. In our experience, grade I injuries are managed nonoperatively and RTS is allowed at 4 to 6 weeks. Grade II injuries are also managed nonoperatively and RTS is allowed at 6 to 8 weeks. Grade III injuries are generally allowed RTS at 8 to 12 weeks and may be considered for surgery in the context of concomitant injuries (eg, posteromedial capsular injury, multiligamentous knee injuries, and meniscal injuries). In some athletes, we consider using a varus unloader brace to help maximize decreased stress on the MCL while still allowing the athlete to be fully weight-bearing. We have found it less ideal to limit weight-bearing in elite athletes, which may negatively affect overall lower extremity neuromuscular proprioception and potentially prolong a safe return to play. Some athletes may experience prolonged soreness at the MCL femoral or tibial attachment despite being able to return to play. It is important to counsel athletes about these prolonged symptoms to set expectations, as this may even occur with grade I MCL injuries. Other rare instances where surgical management may be indicated include persistent pain and instability following nonoperative treatment of grade III injuries and highly displaced tibial avulsions of the ligament resulting in poor healing.^59,60

Data regarding LCL injuries in soccer are extremely sparse. In our experience, treatment and RTS rates for isolated LCL injuries are similar to those for MCL injuries. However, it is worth noting that one-quarter of LCL injuries may occur in combination with injury to other posterolateral corner structures.⁵³

PCL injuries are more commonly associated with vehicular trauma but have also been reported to occur in sports at a rate of 33% to 40%.^61,62 The mechanism of injury in athletes generally involves a fall onto the hyperflexed knee with the foot in plantarflexion or a direct blow to the anterior tibia in a flexed knee.^62,63 Classification of PCL injuries is based on posterior translation of the tibia relative to the femur with the knee flexed to 90°(grade I: 1-5 mm, grade II: 6-10 mm, grade III: >10 mm). In one cohort of 62 patients with isolated PCL injuries, soccer was found to be among the top 5 causes of injury.⁶⁴ A Scandinavian review of 1287 patients who underwent PCL reconstruction found soccer to be the sport with the highest number of injuries (13.1%).⁶⁵ The goalkeeper was most commonly subjected to this injury.⁶² Krutsch and colleagues⁵⁴ compared PCL injuries in new, professional soccer players to those in players at the closest amateur level of play. In their series, 90% of PCL injuries occurred during preseason in players who were at a lower level of play in the previous season. This finding suggested that a rapid increase in training and playing intensity may have been a significant risk factor for PCL injury. Substantial literature supporting nonoperative or operative management of PCL injuries in soccer athletes is currently lacking. Historically, nonoperative treatment has been the initial management for isolated PCL injuries; however, surgical intervention has become increasingly used for both isolated and combined PCL injuries.⁶⁶

Continue to: CARTILAGE AND MENISCAL INJURIES...

CARTILAGE AND MENISCAL INJURIES

The prevalence of osteoarthritis (OA) in retired soccer players is high.^67,68 Articular cartilage degeneration with subsequent OA occurs in up to 32% of soccer players and ultimately leads to significant disability and retirement from the sport. High physical demands and concomitant knee injuries probably predispose to the development of posttraumatic OA.^69-71

Several techniques addressing cartilage débridement or restoration have been reported, with successful RTS but with variable durability.^72-75 Recently, Andrade and colleagues⁷⁶ performed a systematic review of 217 articular cartilage defects in soccer players that were treated using restoration techniques, including chondroplasty, microfracture, autologous chondrocyte implantation (ACI), and osteochondral autograft. Although no superior technique could be ascertained, microfracture and osteochondral autograft procedures led to the quickest return to play, and ACI techniques enhanced long-standing clinical and functional results.⁷⁶ More recently, osteochondral allograft transplantation has also been described with an 84% return to some level of activity (including soccer) and 60% of athletes returning to high-level sports participation at a mean follow-up of 4.5 years⁷⁷ (Figures 3A-3C). Although chondroplasty may be successful and allow for a quicker return to play in some soccer players (return to play from 6-12 weeks), the authors believe that a strong cartilage scaffold repair strategy with early weight-bearing, including osteochondral autograft and allograft procedures (return to play from 6-9 months), must also be considered in focal chondral defects to optimize both short-term and potential long-term success.

Meniscal injuries are also prevalent in the soccer population, and consistent with ACL injuries, female players are at least twice as likely to sustain a meniscal tear.^78,79 Meniscal damage can occur in isolation or in association with ACL rupture. Repair techniques should be strongly considered as chondral changes in the setting of meniscal deficiency are a significant short- and long-term concern for elite athletes. However, due to intrinsically poor healing potential, partial meniscectomy is unfortunately more often performed.^79,80 In either case, meniscal deficiency is recognized as a precursor to the development of OA as meniscal functionality is lost and the articular cartilage is subjected to increased biomechanical loading.^81,82 Nawabi and colleagues⁸³ analyzed RTS in 90 professional soccer players following partial meniscectomy. Median RTS was at 7 weeks for lateral meniscectomies and at 5 weeks for medial meniscectomies. RTS probability was 5.99 times greater after medial meniscectomy at all time points. Lateral meniscectomies were associated with an increased risk of postoperative adverse events, reoperation, and a significantly lower rate of return to play.⁸³ In the case of severe meniscal deficiency, particularly post-meniscectomy, meniscal allograft transplantation (MAT) may be considered. In a series of MATs in lower division Spanish players, 12/14 (85.7%) returned to play at an average of 7.6 months.⁸⁴ A more recent series of professional players reported 9/12 (75%) RTS as professionals and 2/12 (17%) as semiprofessionals at an average of 10.5 months.⁸⁵ The authors’ strong preference is to perform meniscus-saving procedures whenever possible. Due to the longer recovery and return to play associated with meniscus repair than partial meniscectomy, most of the soccer players will often prefer to proceed with partial meniscectomy. Despite the ultimate treatment, it is critical that the surgeon and the soccer player have an in-depth conversation concerning the risks and benefits for each procedure and individualize treatment to the individual soccer player accordingly.

Continue to: INJURY PREVENTION...

INJURY PREVENTION

Given the breadth and the prevalence of soccer-related injuries, the FIFA11+ program was developed in 2006 as an injury prevention measure (Figure 4). The warm-up program includes 15 structured exercises emphasizing core stabilization, thigh muscle training, proprioception, dynamic stabilization, and plyometric exercises. The routine is believed to be easily executed and effective at preventing the incidence of noncontact injuries.^86,87 Recently, Sadigursky and colleagues¹ performed a systematic review of randomized clinical trials examining the efficacy of FIFA11+. The authors reported a reduction in injuries by 30% and a relative risk of 0.70 for lower limb injuries, highlighting the significant preventative importance of the program.¹ Post-training programs may also be beneficial as it has been shown that performing FIFA11+ both before and after training reduced overall injury rates in male, amateur soccer players.⁸⁸ Regardless of the prevention program, it is critical that every league, team, medical team, and athlete have a thorough injury prevention strategy to help keep players healthy and not wait until they have instead sustained a significant injury.

CONCLUSION

Knee injuries are common in soccer, with an alarming number of ACL injuries, as well as other significant pathology. Understanding the unique epidemiology, risk factors, treatment, and injury prevention strategies is critically important in helping medical professionals provide care for all levels of elite soccer players.

SAN DIEGO – Being prepared to manage difficult dislocations is key to maintaining the flow of patient care in any emergency department.

In a video interview at the annual meeting of the American College of Emergency Physicians, Danielle D. Campagne, MD, FACEP, shared her clinical pearls for managing dislocations of the jaw, hip, ankle, and shoulder.

Dr. Campagne is an emergency medicine physician who practices at Community Regional Medical Center in Fresno, Calif. She is also vice chief of emergency medicine at University of California, San Francisco, Fresno. She reported having no financial disclosures.

dbrunk@mdedge.com

SAN DIEGO – Being prepared to manage difficult dislocations is key to maintaining the flow of patient care in any emergency department.

In a video interview at the annual meeting of the American College of Emergency Physicians, Danielle D. Campagne, MD, FACEP, shared her clinical pearls for managing dislocations of the jaw, hip, ankle, and shoulder.

Dr. Campagne is an emergency medicine physician who practices at Community Regional Medical Center in Fresno, Calif. She is also vice chief of emergency medicine at University of California, San Francisco, Fresno. She reported having no financial disclosures.

dbrunk@mdedge.com

SAN DIEGO – Being prepared to manage difficult dislocations is key to maintaining the flow of patient care in any emergency department.

In a video interview at the annual meeting of the American College of Emergency Physicians, Danielle D. Campagne, MD, FACEP, shared her clinical pearls for managing dislocations of the jaw, hip, ankle, and shoulder.

Dr. Campagne is an emergency medicine physician who practices at Community Regional Medical Center in Fresno, Calif. She is also vice chief of emergency medicine at University of California, San Francisco, Fresno. She reported having no financial disclosures.

dbrunk@mdedge.com

ABSTRACT

Cryotherapy is the use of the anti-inflammatory and analgesic properties of ice to facilitate healing. Cryotherapy mediates these salutatory effects by reducing blood flow to the site of injury, down-regulating the production of inflammatory and pain-inducing prostaglandins, and diminishing the conductive ability of nerve endings. It is commonly used postoperatively in orthopedics to decrease analgesic requirements and blood loss as well as to increase range of motion, despite limited literature on its ability to produce such therapeutic effects in clinical practice. This article examines the available literature and the scientific evidence for the use and efficacy of cryotherapy in post-surgical orthopedic patients. It also reviews the potential pitfalls associated with improper use. Overall, this review seeks to provide insight into when, or whether, cryotherapy is appropriate for orthopedic patients during surgical recovery.

Continue to: Cold therapy has been a mainstay of medical treatment...

Cold therapy has been a mainstay of medical treatment since the days of Hippocrates. Initially used by ancient Egyptians to mitigate inflammation and by Hippocrates himself to treat hemorrhage, the therapeutic applications of ice evolved throughout history to become part of the treatment algorithm for a variety of health conditions.¹ Ice made an ideal numbing agent for limb amputations and an anesthetic for certain cancers, but truly became ubiquitous when the first cold pack meant for medicinal use was patented in the early 1970s.^1,2 Despite their armamentarium of advanced treatment modalities, physicians in the modern era continue to prescribe cryotherapy for their patients, particularly in the field of orthopedics. Most athletes know the “RICE” (Rest, Ice, Compression, Elevation) protocol and utilize it to minimize inflammation associated with soft tissue injuries.

Inflammation is a physiologic response to noxious stimuli. Cell damage results in the production of inflammatory mediators including prostaglandins, which play a crucial role in the vasodilation and pain associated with inflammation. Vasodilation and increased blood flow manifest as swelling, which can cause pain by putting pressure on nerve endings. The inflammatory prostaglandin E₂ (PGE₂) causes local increases in temperature and mediates pain.^3,4 The application of cold therapy attenuates inflammatory microvascular and hemodynamic changes, reducing some of the deleterious effects of inflammation and minimizing pain. Animal models demonstrate that cryotherapy restores functional capillary density, reverses tumor necrosis factor-α (TNF-α)-induced microvasculature damage, and reduces the production of thrombogenic thromboxanes in injured soft tissue.⁵ Additionally, cold therapy after knee arthroscopy is associated with lower concentrations of PGE₂ in the knee.³ Local cooling acts at the cellular level to decrease edema, reduce pain, and slow blood flow to the affected area, with the overall effect of alleviating inflammation.^4,5

Cryotherapy is standard practice in postoperative orthopedic care, but there is limited literature demonstrating its efficacy in this setting. In addition, the advent of more advanced wearable cooling systems necessitates a thorough comparison of the various cryotherapy mechanisms both from healthcare and economic perspectives. The goal of this article is to examine the benefits of cryotherapy in the postoperative management of orthopedic surgical interventions and to review the effectiveness of differing types of cryotherapy. A secondary goal of this article is to review the literature on the adverse effects of cryotherapy in order to increase physician awareness of this issue and highlight the importance of patient education when utilizing cryotherapy postoperatively.

BENEFITS OF CRYOTHERAPY

Three standard types of cryotherapy are prescribed as postoperative therapy in orthopedics: compressive cryotherapy, continuous flow cryotherapy, and the application of ice. All aim to decrease the amount of inflammation of the surgical site, reduce patient pain, and aid in the recovery process. The application of ice or other cooling pack devices without compression is the most commonly used method, likely because it is the most economical and user-friendly cryotherapy option. Compressive cryotherapy is the application of ice or an ice pack secured to the site with a bandage or other device in a manner that also applies pressure to the site of injury. Finally, continuous flow cryotherapy systems are typically connected to a refrigeration control unit and apply compressive cooling through the uninterrupted flow of cold water or gas through a wrap around the injured site. Examples include the Game Ready^® (CoolSystems, Inc.), Cryo/Cuff^® IC Cooler (DJO Global), and Hilotherm Homecare (Hilotherm GmbH) systems, which are marketed as an improvement over traditional forms of cold therapy, as they are capable of cooling for hours at a time, allow for nighttime use, and provide the operator with temperature control.^6-8

Postoperative cryotherapy is prescribed for a wide variety of orthopedic procedures, including anterior cruciate ligament (ACL) reconstruction surgery, rotator cuff surgery, and total knee arthroplasty (TKA). Current literature includes many studies monitoring postoperative outcomes in patients using cryotherapy as part of their treatment regimen, with the primary endpoints being visual analog scale (VAS) scores, analgesic consumption, and range of motion (ROM).^9-16 As demonstrated by in Table 1, these studies do not provide conclusive evidence that cryotherapy significantly alters postoperative outcomes, despite its ubiquitous use by the orthopedics community. In fact, the literature reflects a seeming lack of consensus regarding the effect of cryotherapy on analgesic requirements, pain, and joint mobility following procedures. Interestingly, of the studies represented in Table 1, only half analyzed all 3 postoperative measures (analgesic consumption, pain, and ROM). Furthermore, solely Morsi¹³ concluded that cryotherapy resulted in significant improvements in all 3 outcome measures in a trial involving only 30 patients. Kullenberg and colleagues¹² performed the largest study, but still included only 86 patients. In addition, all the studies focused on 1 joint or procedure. Thus, despite evidence that cryotherapy reduces inflammation at a molecular level, current literature does not unequivocally support the common belief that cryotherapy benefits patients in practice. More robust studies that include an analysis of analgesic consumption, VAS scores, and ROM (at minimum) and compare the relative efficacy of cryotherapy across joint types and procedures are necessary to determine whether postoperative cryotherapy in orthopedics is appropriate.

Table 1. Results from Studies that Compared Cryotherapy to Standard Care Within the First 2 Weeks Following Surgery

Continue to: ADVANCED CRYOTHERAPY DEVICES...

ADVANCED CRYOTHERAPY DEVICES

Several recent studies explored the relative postoperative benefits of advanced cryotherapeutics in lieu of the traditional ice pack.^6,7,17-21 As reflected in Table 2, these studies, much like the literature comparing cryotherapy to the control, do not reveal significant benefits of continuous flow cryotherapy after surgery. In fact, the only outcome measure that was found to differ significantly in more than 1 study was ROM. Though the makers of advanced cryotherapy systems market them as a vast improvement over traditional forms of cold therapy, there is insufficient evidence to support such claims. Even the most robust study that included 280 patients failed to show significant differences in the analgesic use and ROM after surgery.²⁰ Of note, all but 1 study compared traditional and advanced cryotherapy following procedures on the knee. Additional research exploring outcomes after surgery on other joints is necessary before any conclusions can be made regarding postoperative benefits or risks within orthopedics more generally.

RISKS AND ADVERSE EFFECTS OF CRYOTHERAPY

A rigorous analysis of the benefits of cryotherapy ought to incorporate other factors in addition to improvements in analgesic consumption, VAS score, and ROM. These include the financial and time investment involved in the use of continuous flow cryotherapy, which the majority of studies do not consider. Though many authors acknowledge that continuous flow cryotherapy is expensive, to our knowledge, none have yet performed a formal economic analysis of the cost of advanced cryotherapy to the patient as well as to the healthcare system at large.^{6,7,13,18,22-24} Dickinson and colleagues²⁴ calculated the total cost of cryotherapy and rehabilitation following rotator cuff repair, but addressed only the up-front cost of the cold therapy system. For context, Table 3 summarizes the retail cost of the most popular cryotherapy devices on the market. Based on this information alone, it seems reasonable to conclude that these systems are associated with significantly more cost than traditional forms of cold therapy, and therefore would be an undesirable option for patients or hospital systems. Nevertheless, cost considerations are more nuanced than a simple comparison of price, necessitating more advanced economic analyses. Substantial savings may be on the table if future studies are able to prove postoperative cryotherapy shortens hospital stays, reduces medication costs, and results in fewer physical therapy sessions. Moreover, if all this is true, patients may experience quicker recovery and have overall greater post-procedure satisfaction.

Table 3. Cost of Most Popular Cryotherapy Units

Patient education required for optimal use of advanced cold therapy is another aspect of cryotherapy that is poorly represented in the literature. As Dickinson and colleagues²⁴ point out, because it eliminates some dependency on the patient to remember to ice appropriately, continuous flow cryotherapy may have a positive impact on compliance and therefore yield improved outcomes.²⁴ Hospital staff may be required to spend additional time with patients. However, this is necessary to ensure proper understanding on how to operate the system and avoid adverse outcomes. Patients may also find the large coolers inconvenient and may therefore be reluctant to use them, finding traditional ice more manageable. Future studies should consider gathering data on patient education, compliance, and overall reception/satisfaction to complete a more holistic investigation of the role of postoperative cryotherapy in orthopedics.

Cryotherapy is not without adverse outcomes, which have been documented primarily in the form of case study reports. Relevant case studies cited adverse outcomes including frostbite/skin loss, compartment syndrome, and perniosis as potential dangers of postoperative cryotherapy in orthopedics (Table 4).^25-30 As an example, a patient recovering from patellar-tendon repair experienced bilateral frostbite and skin loss following 2 weeks of uninterrupted use of cryotherapy without any barrier between his skin and the system.²⁹ A similar case study described 2 female patients, one recovering from a TKA and the other from a tibial revision of arthroplasty, who used cryotherapy systems without cessation and experienced frostbite and skin necrosis over the entirety of their knees.²⁶ A third case study exploring 4 incidents of patellar frostbite and necrosis following knee arthroscopies proposed that poor patient understanding of proper cryotherapy use as well as poor recognition of the signs of frostbite contributed to these adverse outcomes. Furthermore, the cryotherapy brace used by all 4 patients included a feature designed to counteract patellar inflammation that also may have increased the likelihood of frostbite in this area due to poor tissue insulation. The authors noted that following the incidents, the makers of the brace removed patellar coverage to prevent future occurrences.³⁰

Abbreviations: ACL, anterior cruciate ligament; TKA, total knee arthroplasty.

Frostbite linked to cryotherapy has also occurred following orthopedic procedures outside the knee. Brown and Hahn²⁵ described 2 young females who developed skin necrosis following podiatric surgeries and constant cold therapy for roughly a week. Notably, 1 patient had cold sensitivity, which likely put her at an increased baseline risk of experiencing frostbite while using cryotherapy. Tissue necrosis is not the only danger of cold therapy discussed in this study. Surprisingly, 1 patient also developed compartment syndrome.²⁵ Khajavi and colleagues²⁷ also documented postoperative compartment syndrome in a patient following an arthroscopic osteochondral autograft transfer, which they attributed to reperfusion injury in the wake of first-degree frostbite. Hospital personnel also instructed this patient to use his cryotherapy system without interruption at the coldest temperature tolerable, contrary to manufacturer’s instructions.²⁷

Continue to: King and colleagues...

King and colleagues²⁸ described 2 cases of patients complaining of nodules, papules, and plaques soon after ACL reconstruction and the initiation of cryotherapy. A histological examination of their skin lesions demonstrated the presence of a perivascular and periadnexal superficial and deep lymphocytic infiltrate associated with perniosis. Dermatologists associated the perniosis with the cryotherapy cuff adhesive mechanisms, as their locations matched those of the lesions and symptoms subsided after cessation of cuff usage.²⁸

Cases of adverse effects with perioperative cryotherapy have also occurred at our own institution. The authors obtained informed written consent from the patients to print and publish their images. In 2 separate incidents, patients overdid icing and experienced rather extreme side effects including burns and blisters (Figures 1 and 2). In light of these adverse events, the physicians have questioned whether RICE ought to be part of their standard perioperative recommendations. These physicians are not alone in their uncertainty. Interestingly, even Mirkin,³¹ who coined the RICE mnemonic, now believes that consistent icing post-injury actually inhibits the body’s natural inflammatory healing response, delaying rather than speeding recovery, and suggests that icing ought to be used for pain control only.

DISCUSSION

Though there is ample literature supporting the common belief that cryotherapy minimizes inflammation at the cellular level, whether or not it results in meaningful improvements in post-surgical orthopedic outcomes remains unclear. Table 1 reflects a dearth of evidence to support the widespread current practice of cold therapy following orthopedic procedures, but few studies could demonstrate a significant difference in the analgesic use, VAS score, or ROM between cryotherapy and control groups. It is worth noting that these studies used different cryotherapy systems. Though in theory the continuous flow cryotherapy systems are similarly designed, there are potential differences among them that have not been controlled for in this analysis. All studies had <90 participants and focused on a single joint or procedure, making it difficult to draw large scale conclusions about the utility of cold therapy in the postoperative orthopedic population at large. Furthermore, researchers measured endpoints at a range of time intervals that were inconsistent across studies. In some cases, the significance of the impact of cryotherapy on recovery within a single study differed based on the time point at which researchers measured outcomes.^12-14 This raises the question as to whether cryotherapy has no benefits, or whether they are simply time-dependent. Future studies should seek to ascertain whether there is a postoperative time window in which cryotherapy could potentially expedite the recovery process.

Similarly, Table 2 shows a lack of consensus regarding the effect of advanced cryotherapy when compared to traditional ice application on pain, analgesic use, and joint mobility after surgery. However, all but 1 of these studies focused on knee procedures. Therefore, our findings may not be applicable to orthopedic surgeries on other joints. Nevertheless, the use of advanced cryotherapy in postoperative orthopedic care may wane if researchers continue to show that it is no more beneficial than its far less expensive counterpart of ice and an ace bandage.

The case studies discussed in this review serve as cautionary tales of the dangers of cryotherapy when used improperly. Though frostbite and subsequent tissue necrosis seem most common, physicians should be made aware that compartment syndrome and perniosis are also possible consequences. Orthopedic patients perhaps have an increased risk of developing these side effects due to the nature of their injuries and the large cutaneous surface area to which cryotherapy is applied. These outcomes could seemingly be avoided with improved educational initiatives targeted at both healthcare personnel and patients. Orthopedic surgeons might consider adding a short, instructive video focusing on proper usage as well as signs of adverse events to their discharge protocol to limit occurrences of these pitfalls associated with cryotherapy.

CONCLUSION

There is inadequate literature to support the of use postoperative cryotherapy of any kind in the field of orthopedics at this time. More robust, standardized studies, and a formidable economic analysis of advanced cold therapy systems are necessary before physicians prescribing cryotherapy can be confident that they are augmenting patient recovery. Nevertheless, as new developments in medicinal cryotherapy occur, it may be possible for the orthopedic community to wield its salutatory effects to limit complications and improve post-surgical outcomes.

ABSTRACT

Cryotherapy is the use of the anti-inflammatory and analgesic properties of ice to facilitate healing. Cryotherapy mediates these salutatory effects by reducing blood flow to the site of injury, down-regulating the production of inflammatory and pain-inducing prostaglandins, and diminishing the conductive ability of nerve endings. It is commonly used postoperatively in orthopedics to decrease analgesic requirements and blood loss as well as to increase range of motion, despite limited literature on its ability to produce such therapeutic effects in clinical practice. This article examines the available literature and the scientific evidence for the use and efficacy of cryotherapy in post-surgical orthopedic patients. It also reviews the potential pitfalls associated with improper use. Overall, this review seeks to provide insight into when, or whether, cryotherapy is appropriate for orthopedic patients during surgical recovery.

Continue to: Cold therapy has been a mainstay of medical treatment...

Cold therapy has been a mainstay of medical treatment since the days of Hippocrates. Initially used by ancient Egyptians to mitigate inflammation and by Hippocrates himself to treat hemorrhage, the therapeutic applications of ice evolved throughout history to become part of the treatment algorithm for a variety of health conditions.¹ Ice made an ideal numbing agent for limb amputations and an anesthetic for certain cancers, but truly became ubiquitous when the first cold pack meant for medicinal use was patented in the early 1970s.^1,2 Despite their armamentarium of advanced treatment modalities, physicians in the modern era continue to prescribe cryotherapy for their patients, particularly in the field of orthopedics. Most athletes know the “RICE” (Rest, Ice, Compression, Elevation) protocol and utilize it to minimize inflammation associated with soft tissue injuries.

Inflammation is a physiologic response to noxious stimuli. Cell damage results in the production of inflammatory mediators including prostaglandins, which play a crucial role in the vasodilation and pain associated with inflammation. Vasodilation and increased blood flow manifest as swelling, which can cause pain by putting pressure on nerve endings. The inflammatory prostaglandin E₂ (PGE₂) causes local increases in temperature and mediates pain.^3,4 The application of cold therapy attenuates inflammatory microvascular and hemodynamic changes, reducing some of the deleterious effects of inflammation and minimizing pain. Animal models demonstrate that cryotherapy restores functional capillary density, reverses tumor necrosis factor-α (TNF-α)-induced microvasculature damage, and reduces the production of thrombogenic thromboxanes in injured soft tissue.⁵ Additionally, cold therapy after knee arthroscopy is associated with lower concentrations of PGE₂ in the knee.³ Local cooling acts at the cellular level to decrease edema, reduce pain, and slow blood flow to the affected area, with the overall effect of alleviating inflammation.^4,5

Cryotherapy is standard practice in postoperative orthopedic care, but there is limited literature demonstrating its efficacy in this setting. In addition, the advent of more advanced wearable cooling systems necessitates a thorough comparison of the various cryotherapy mechanisms both from healthcare and economic perspectives. The goal of this article is to examine the benefits of cryotherapy in the postoperative management of orthopedic surgical interventions and to review the effectiveness of differing types of cryotherapy. A secondary goal of this article is to review the literature on the adverse effects of cryotherapy in order to increase physician awareness of this issue and highlight the importance of patient education when utilizing cryotherapy postoperatively.

BENEFITS OF CRYOTHERAPY

Three standard types of cryotherapy are prescribed as postoperative therapy in orthopedics: compressive cryotherapy, continuous flow cryotherapy, and the application of ice. All aim to decrease the amount of inflammation of the surgical site, reduce patient pain, and aid in the recovery process. The application of ice or other cooling pack devices without compression is the most commonly used method, likely because it is the most economical and user-friendly cryotherapy option. Compressive cryotherapy is the application of ice or an ice pack secured to the site with a bandage or other device in a manner that also applies pressure to the site of injury. Finally, continuous flow cryotherapy systems are typically connected to a refrigeration control unit and apply compressive cooling through the uninterrupted flow of cold water or gas through a wrap around the injured site. Examples include the Game Ready^® (CoolSystems, Inc.), Cryo/Cuff^® IC Cooler (DJO Global), and Hilotherm Homecare (Hilotherm GmbH) systems, which are marketed as an improvement over traditional forms of cold therapy, as they are capable of cooling for hours at a time, allow for nighttime use, and provide the operator with temperature control.^6-8

Postoperative cryotherapy is prescribed for a wide variety of orthopedic procedures, including anterior cruciate ligament (ACL) reconstruction surgery, rotator cuff surgery, and total knee arthroplasty (TKA). Current literature includes many studies monitoring postoperative outcomes in patients using cryotherapy as part of their treatment regimen, with the primary endpoints being visual analog scale (VAS) scores, analgesic consumption, and range of motion (ROM).^9-16 As demonstrated by in Table 1, these studies do not provide conclusive evidence that cryotherapy significantly alters postoperative outcomes, despite its ubiquitous use by the orthopedics community. In fact, the literature reflects a seeming lack of consensus regarding the effect of cryotherapy on analgesic requirements, pain, and joint mobility following procedures. Interestingly, of the studies represented in Table 1, only half analyzed all 3 postoperative measures (analgesic consumption, pain, and ROM). Furthermore, solely Morsi¹³ concluded that cryotherapy resulted in significant improvements in all 3 outcome measures in a trial involving only 30 patients. Kullenberg and colleagues¹² performed the largest study, but still included only 86 patients. In addition, all the studies focused on 1 joint or procedure. Thus, despite evidence that cryotherapy reduces inflammation at a molecular level, current literature does not unequivocally support the common belief that cryotherapy benefits patients in practice. More robust studies that include an analysis of analgesic consumption, VAS scores, and ROM (at minimum) and compare the relative efficacy of cryotherapy across joint types and procedures are necessary to determine whether postoperative cryotherapy in orthopedics is appropriate.

Table 1. Results from Studies that Compared Cryotherapy to Standard Care Within the First 2 Weeks Following Surgery

Continue to: ADVANCED CRYOTHERAPY DEVICES...

ADVANCED CRYOTHERAPY DEVICES

Several recent studies explored the relative postoperative benefits of advanced cryotherapeutics in lieu of the traditional ice pack.^6,7,17-21 As reflected in Table 2, these studies, much like the literature comparing cryotherapy to the control, do not reveal significant benefits of continuous flow cryotherapy after surgery. In fact, the only outcome measure that was found to differ significantly in more than 1 study was ROM. Though the makers of advanced cryotherapy systems market them as a vast improvement over traditional forms of cold therapy, there is insufficient evidence to support such claims. Even the most robust study that included 280 patients failed to show significant differences in the analgesic use and ROM after surgery.²⁰ Of note, all but 1 study compared traditional and advanced cryotherapy following procedures on the knee. Additional research exploring outcomes after surgery on other joints is necessary before any conclusions can be made regarding postoperative benefits or risks within orthopedics more generally.

RISKS AND ADVERSE EFFECTS OF CRYOTHERAPY

A rigorous analysis of the benefits of cryotherapy ought to incorporate other factors in addition to improvements in analgesic consumption, VAS score, and ROM. These include the financial and time investment involved in the use of continuous flow cryotherapy, which the majority of studies do not consider. Though many authors acknowledge that continuous flow cryotherapy is expensive, to our knowledge, none have yet performed a formal economic analysis of the cost of advanced cryotherapy to the patient as well as to the healthcare system at large.^{6,7,13,18,22-24} Dickinson and colleagues²⁴ calculated the total cost of cryotherapy and rehabilitation following rotator cuff repair, but addressed only the up-front cost of the cold therapy system. For context, Table 3 summarizes the retail cost of the most popular cryotherapy devices on the market. Based on this information alone, it seems reasonable to conclude that these systems are associated with significantly more cost than traditional forms of cold therapy, and therefore would be an undesirable option for patients or hospital systems. Nevertheless, cost considerations are more nuanced than a simple comparison of price, necessitating more advanced economic analyses. Substantial savings may be on the table if future studies are able to prove postoperative cryotherapy shortens hospital stays, reduces medication costs, and results in fewer physical therapy sessions. Moreover, if all this is true, patients may experience quicker recovery and have overall greater post-procedure satisfaction.

Table 3. Cost of Most Popular Cryotherapy Units

Patient education required for optimal use of advanced cold therapy is another aspect of cryotherapy that is poorly represented in the literature. As Dickinson and colleagues²⁴ point out, because it eliminates some dependency on the patient to remember to ice appropriately, continuous flow cryotherapy may have a positive impact on compliance and therefore yield improved outcomes.²⁴ Hospital staff may be required to spend additional time with patients. However, this is necessary to ensure proper understanding on how to operate the system and avoid adverse outcomes. Patients may also find the large coolers inconvenient and may therefore be reluctant to use them, finding traditional ice more manageable. Future studies should consider gathering data on patient education, compliance, and overall reception/satisfaction to complete a more holistic investigation of the role of postoperative cryotherapy in orthopedics.

Cryotherapy is not without adverse outcomes, which have been documented primarily in the form of case study reports. Relevant case studies cited adverse outcomes including frostbite/skin loss, compartment syndrome, and perniosis as potential dangers of postoperative cryotherapy in orthopedics (Table 4).^25-30 As an example, a patient recovering from patellar-tendon repair experienced bilateral frostbite and skin loss following 2 weeks of uninterrupted use of cryotherapy without any barrier between his skin and the system.²⁹ A similar case study described 2 female patients, one recovering from a TKA and the other from a tibial revision of arthroplasty, who used cryotherapy systems without cessation and experienced frostbite and skin necrosis over the entirety of their knees.²⁶ A third case study exploring 4 incidents of patellar frostbite and necrosis following knee arthroscopies proposed that poor patient understanding of proper cryotherapy use as well as poor recognition of the signs of frostbite contributed to these adverse outcomes. Furthermore, the cryotherapy brace used by all 4 patients included a feature designed to counteract patellar inflammation that also may have increased the likelihood of frostbite in this area due to poor tissue insulation. The authors noted that following the incidents, the makers of the brace removed patellar coverage to prevent future occurrences.³⁰

Abbreviations: ACL, anterior cruciate ligament; TKA, total knee arthroplasty.

Frostbite linked to cryotherapy has also occurred following orthopedic procedures outside the knee. Brown and Hahn²⁵ described 2 young females who developed skin necrosis following podiatric surgeries and constant cold therapy for roughly a week. Notably, 1 patient had cold sensitivity, which likely put her at an increased baseline risk of experiencing frostbite while using cryotherapy. Tissue necrosis is not the only danger of cold therapy discussed in this study. Surprisingly, 1 patient also developed compartment syndrome.²⁵ Khajavi and colleagues²⁷ also documented postoperative compartment syndrome in a patient following an arthroscopic osteochondral autograft transfer, which they attributed to reperfusion injury in the wake of first-degree frostbite. Hospital personnel also instructed this patient to use his cryotherapy system without interruption at the coldest temperature tolerable, contrary to manufacturer’s instructions.²⁷

Continue to: King and colleagues...

King and colleagues²⁸ described 2 cases of patients complaining of nodules, papules, and plaques soon after ACL reconstruction and the initiation of cryotherapy. A histological examination of their skin lesions demonstrated the presence of a perivascular and periadnexal superficial and deep lymphocytic infiltrate associated with perniosis. Dermatologists associated the perniosis with the cryotherapy cuff adhesive mechanisms, as their locations matched those of the lesions and symptoms subsided after cessation of cuff usage.²⁸

Cases of adverse effects with perioperative cryotherapy have also occurred at our own institution. The authors obtained informed written consent from the patients to print and publish their images. In 2 separate incidents, patients overdid icing and experienced rather extreme side effects including burns and blisters (Figures 1 and 2). In light of these adverse events, the physicians have questioned whether RICE ought to be part of their standard perioperative recommendations. These physicians are not alone in their uncertainty. Interestingly, even Mirkin,³¹ who coined the RICE mnemonic, now believes that consistent icing post-injury actually inhibits the body’s natural inflammatory healing response, delaying rather than speeding recovery, and suggests that icing ought to be used for pain control only.

DISCUSSION

Though there is ample literature supporting the common belief that cryotherapy minimizes inflammation at the cellular level, whether or not it results in meaningful improvements in post-surgical orthopedic outcomes remains unclear. Table 1 reflects a dearth of evidence to support the widespread current practice of cold therapy following orthopedic procedures, but few studies could demonstrate a significant difference in the analgesic use, VAS score, or ROM between cryotherapy and control groups. It is worth noting that these studies used different cryotherapy systems. Though in theory the continuous flow cryotherapy systems are similarly designed, there are potential differences among them that have not been controlled for in this analysis. All studies had <90 participants and focused on a single joint or procedure, making it difficult to draw large scale conclusions about the utility of cold therapy in the postoperative orthopedic population at large. Furthermore, researchers measured endpoints at a range of time intervals that were inconsistent across studies. In some cases, the significance of the impact of cryotherapy on recovery within a single study differed based on the time point at which researchers measured outcomes.^12-14 This raises the question as to whether cryotherapy has no benefits, or whether they are simply time-dependent. Future studies should seek to ascertain whether there is a postoperative time window in which cryotherapy could potentially expedite the recovery process.

Similarly, Table 2 shows a lack of consensus regarding the effect of advanced cryotherapy when compared to traditional ice application on pain, analgesic use, and joint mobility after surgery. However, all but 1 of these studies focused on knee procedures. Therefore, our findings may not be applicable to orthopedic surgeries on other joints. Nevertheless, the use of advanced cryotherapy in postoperative orthopedic care may wane if researchers continue to show that it is no more beneficial than its far less expensive counterpart of ice and an ace bandage.

The case studies discussed in this review serve as cautionary tales of the dangers of cryotherapy when used improperly. Though frostbite and subsequent tissue necrosis seem most common, physicians should be made aware that compartment syndrome and perniosis are also possible consequences. Orthopedic patients perhaps have an increased risk of developing these side effects due to the nature of their injuries and the large cutaneous surface area to which cryotherapy is applied. These outcomes could seemingly be avoided with improved educational initiatives targeted at both healthcare personnel and patients. Orthopedic surgeons might consider adding a short, instructive video focusing on proper usage as well as signs of adverse events to their discharge protocol to limit occurrences of these pitfalls associated with cryotherapy.

CONCLUSION

There is inadequate literature to support the of use postoperative cryotherapy of any kind in the field of orthopedics at this time. More robust, standardized studies, and a formidable economic analysis of advanced cold therapy systems are necessary before physicians prescribing cryotherapy can be confident that they are augmenting patient recovery. Nevertheless, as new developments in medicinal cryotherapy occur, it may be possible for the orthopedic community to wield its salutatory effects to limit complications and improve post-surgical outcomes.

ABSTRACT

Cryotherapy is the use of the anti-inflammatory and analgesic properties of ice to facilitate healing. Cryotherapy mediates these salutatory effects by reducing blood flow to the site of injury, down-regulating the production of inflammatory and pain-inducing prostaglandins, and diminishing the conductive ability of nerve endings. It is commonly used postoperatively in orthopedics to decrease analgesic requirements and blood loss as well as to increase range of motion, despite limited literature on its ability to produce such therapeutic effects in clinical practice. This article examines the available literature and the scientific evidence for the use and efficacy of cryotherapy in post-surgical orthopedic patients. It also reviews the potential pitfalls associated with improper use. Overall, this review seeks to provide insight into when, or whether, cryotherapy is appropriate for orthopedic patients during surgical recovery.

Continue to: Cold therapy has been a mainstay of medical treatment...

Cold therapy has been a mainstay of medical treatment since the days of Hippocrates. Initially used by ancient Egyptians to mitigate inflammation and by Hippocrates himself to treat hemorrhage, the therapeutic applications of ice evolved throughout history to become part of the treatment algorithm for a variety of health conditions.¹ Ice made an ideal numbing agent for limb amputations and an anesthetic for certain cancers, but truly became ubiquitous when the first cold pack meant for medicinal use was patented in the early 1970s.^1,2 Despite their armamentarium of advanced treatment modalities, physicians in the modern era continue to prescribe cryotherapy for their patients, particularly in the field of orthopedics. Most athletes know the “RICE” (Rest, Ice, Compression, Elevation) protocol and utilize it to minimize inflammation associated with soft tissue injuries.

Inflammation is a physiologic response to noxious stimuli. Cell damage results in the production of inflammatory mediators including prostaglandins, which play a crucial role in the vasodilation and pain associated with inflammation. Vasodilation and increased blood flow manifest as swelling, which can cause pain by putting pressure on nerve endings. The inflammatory prostaglandin E₂ (PGE₂) causes local increases in temperature and mediates pain.^3,4 The application of cold therapy attenuates inflammatory microvascular and hemodynamic changes, reducing some of the deleterious effects of inflammation and minimizing pain. Animal models demonstrate that cryotherapy restores functional capillary density, reverses tumor necrosis factor-α (TNF-α)-induced microvasculature damage, and reduces the production of thrombogenic thromboxanes in injured soft tissue.⁵ Additionally, cold therapy after knee arthroscopy is associated with lower concentrations of PGE₂ in the knee.³ Local cooling acts at the cellular level to decrease edema, reduce pain, and slow blood flow to the affected area, with the overall effect of alleviating inflammation.^4,5

Cryotherapy is standard practice in postoperative orthopedic care, but there is limited literature demonstrating its efficacy in this setting. In addition, the advent of more advanced wearable cooling systems necessitates a thorough comparison of the various cryotherapy mechanisms both from healthcare and economic perspectives. The goal of this article is to examine the benefits of cryotherapy in the postoperative management of orthopedic surgical interventions and to review the effectiveness of differing types of cryotherapy. A secondary goal of this article is to review the literature on the adverse effects of cryotherapy in order to increase physician awareness of this issue and highlight the importance of patient education when utilizing cryotherapy postoperatively.

BENEFITS OF CRYOTHERAPY

Three standard types of cryotherapy are prescribed as postoperative therapy in orthopedics: compressive cryotherapy, continuous flow cryotherapy, and the application of ice. All aim to decrease the amount of inflammation of the surgical site, reduce patient pain, and aid in the recovery process. The application of ice or other cooling pack devices without compression is the most commonly used method, likely because it is the most economical and user-friendly cryotherapy option. Compressive cryotherapy is the application of ice or an ice pack secured to the site with a bandage or other device in a manner that also applies pressure to the site of injury. Finally, continuous flow cryotherapy systems are typically connected to a refrigeration control unit and apply compressive cooling through the uninterrupted flow of cold water or gas through a wrap around the injured site. Examples include the Game Ready^® (CoolSystems, Inc.), Cryo/Cuff^® IC Cooler (DJO Global), and Hilotherm Homecare (Hilotherm GmbH) systems, which are marketed as an improvement over traditional forms of cold therapy, as they are capable of cooling for hours at a time, allow for nighttime use, and provide the operator with temperature control.^6-8

Postoperative cryotherapy is prescribed for a wide variety of orthopedic procedures, including anterior cruciate ligament (ACL) reconstruction surgery, rotator cuff surgery, and total knee arthroplasty (TKA). Current literature includes many studies monitoring postoperative outcomes in patients using cryotherapy as part of their treatment regimen, with the primary endpoints being visual analog scale (VAS) scores, analgesic consumption, and range of motion (ROM).^9-16 As demonstrated by in Table 1, these studies do not provide conclusive evidence that cryotherapy significantly alters postoperative outcomes, despite its ubiquitous use by the orthopedics community. In fact, the literature reflects a seeming lack of consensus regarding the effect of cryotherapy on analgesic requirements, pain, and joint mobility following procedures. Interestingly, of the studies represented in Table 1, only half analyzed all 3 postoperative measures (analgesic consumption, pain, and ROM). Furthermore, solely Morsi¹³ concluded that cryotherapy resulted in significant improvements in all 3 outcome measures in a trial involving only 30 patients. Kullenberg and colleagues¹² performed the largest study, but still included only 86 patients. In addition, all the studies focused on 1 joint or procedure. Thus, despite evidence that cryotherapy reduces inflammation at a molecular level, current literature does not unequivocally support the common belief that cryotherapy benefits patients in practice. More robust studies that include an analysis of analgesic consumption, VAS scores, and ROM (at minimum) and compare the relative efficacy of cryotherapy across joint types and procedures are necessary to determine whether postoperative cryotherapy in orthopedics is appropriate.

Table 1. Results from Studies that Compared Cryotherapy to Standard Care Within the First 2 Weeks Following Surgery

Continue to: ADVANCED CRYOTHERAPY DEVICES...

ADVANCED CRYOTHERAPY DEVICES

Several recent studies explored the relative postoperative benefits of advanced cryotherapeutics in lieu of the traditional ice pack.^6,7,17-21 As reflected in Table 2, these studies, much like the literature comparing cryotherapy to the control, do not reveal significant benefits of continuous flow cryotherapy after surgery. In fact, the only outcome measure that was found to differ significantly in more than 1 study was ROM. Though the makers of advanced cryotherapy systems market them as a vast improvement over traditional forms of cold therapy, there is insufficient evidence to support such claims. Even the most robust study that included 280 patients failed to show significant differences in the analgesic use and ROM after surgery.²⁰ Of note, all but 1 study compared traditional and advanced cryotherapy following procedures on the knee. Additional research exploring outcomes after surgery on other joints is necessary before any conclusions can be made regarding postoperative benefits or risks within orthopedics more generally.

RISKS AND ADVERSE EFFECTS OF CRYOTHERAPY

A rigorous analysis of the benefits of cryotherapy ought to incorporate other factors in addition to improvements in analgesic consumption, VAS score, and ROM. These include the financial and time investment involved in the use of continuous flow cryotherapy, which the majority of studies do not consider. Though many authors acknowledge that continuous flow cryotherapy is expensive, to our knowledge, none have yet performed a formal economic analysis of the cost of advanced cryotherapy to the patient as well as to the healthcare system at large.^{6,7,13,18,22-24} Dickinson and colleagues²⁴ calculated the total cost of cryotherapy and rehabilitation following rotator cuff repair, but addressed only the up-front cost of the cold therapy system. For context, Table 3 summarizes the retail cost of the most popular cryotherapy devices on the market. Based on this information alone, it seems reasonable to conclude that these systems are associated with significantly more cost than traditional forms of cold therapy, and therefore would be an undesirable option for patients or hospital systems. Nevertheless, cost considerations are more nuanced than a simple comparison of price, necessitating more advanced economic analyses. Substantial savings may be on the table if future studies are able to prove postoperative cryotherapy shortens hospital stays, reduces medication costs, and results in fewer physical therapy sessions. Moreover, if all this is true, patients may experience quicker recovery and have overall greater post-procedure satisfaction.

Table 3. Cost of Most Popular Cryotherapy Units

Patient education required for optimal use of advanced cold therapy is another aspect of cryotherapy that is poorly represented in the literature. As Dickinson and colleagues²⁴ point out, because it eliminates some dependency on the patient to remember to ice appropriately, continuous flow cryotherapy may have a positive impact on compliance and therefore yield improved outcomes.²⁴ Hospital staff may be required to spend additional time with patients. However, this is necessary to ensure proper understanding on how to operate the system and avoid adverse outcomes. Patients may also find the large coolers inconvenient and may therefore be reluctant to use them, finding traditional ice more manageable. Future studies should consider gathering data on patient education, compliance, and overall reception/satisfaction to complete a more holistic investigation of the role of postoperative cryotherapy in orthopedics.

Cryotherapy is not without adverse outcomes, which have been documented primarily in the form of case study reports. Relevant case studies cited adverse outcomes including frostbite/skin loss, compartment syndrome, and perniosis as potential dangers of postoperative cryotherapy in orthopedics (Table 4).^25-30 As an example, a patient recovering from patellar-tendon repair experienced bilateral frostbite and skin loss following 2 weeks of uninterrupted use of cryotherapy without any barrier between his skin and the system.²⁹ A similar case study described 2 female patients, one recovering from a TKA and the other from a tibial revision of arthroplasty, who used cryotherapy systems without cessation and experienced frostbite and skin necrosis over the entirety of their knees.²⁶ A third case study exploring 4 incidents of patellar frostbite and necrosis following knee arthroscopies proposed that poor patient understanding of proper cryotherapy use as well as poor recognition of the signs of frostbite contributed to these adverse outcomes. Furthermore, the cryotherapy brace used by all 4 patients included a feature designed to counteract patellar inflammation that also may have increased the likelihood of frostbite in this area due to poor tissue insulation. The authors noted that following the incidents, the makers of the brace removed patellar coverage to prevent future occurrences.³⁰

Abbreviations: ACL, anterior cruciate ligament; TKA, total knee arthroplasty.

Frostbite linked to cryotherapy has also occurred following orthopedic procedures outside the knee. Brown and Hahn²⁵ described 2 young females who developed skin necrosis following podiatric surgeries and constant cold therapy for roughly a week. Notably, 1 patient had cold sensitivity, which likely put her at an increased baseline risk of experiencing frostbite while using cryotherapy. Tissue necrosis is not the only danger of cold therapy discussed in this study. Surprisingly, 1 patient also developed compartment syndrome.²⁵ Khajavi and colleagues²⁷ also documented postoperative compartment syndrome in a patient following an arthroscopic osteochondral autograft transfer, which they attributed to reperfusion injury in the wake of first-degree frostbite. Hospital personnel also instructed this patient to use his cryotherapy system without interruption at the coldest temperature tolerable, contrary to manufacturer’s instructions.²⁷

Continue to: King and colleagues...

King and colleagues²⁸ described 2 cases of patients complaining of nodules, papules, and plaques soon after ACL reconstruction and the initiation of cryotherapy. A histological examination of their skin lesions demonstrated the presence of a perivascular and periadnexal superficial and deep lymphocytic infiltrate associated with perniosis. Dermatologists associated the perniosis with the cryotherapy cuff adhesive mechanisms, as their locations matched those of the lesions and symptoms subsided after cessation of cuff usage.²⁸

Cases of adverse effects with perioperative cryotherapy have also occurred at our own institution. The authors obtained informed written consent from the patients to print and publish their images. In 2 separate incidents, patients overdid icing and experienced rather extreme side effects including burns and blisters (Figures 1 and 2). In light of these adverse events, the physicians have questioned whether RICE ought to be part of their standard perioperative recommendations. These physicians are not alone in their uncertainty. Interestingly, even Mirkin,³¹ who coined the RICE mnemonic, now believes that consistent icing post-injury actually inhibits the body’s natural inflammatory healing response, delaying rather than speeding recovery, and suggests that icing ought to be used for pain control only.

DISCUSSION

Though there is ample literature supporting the common belief that cryotherapy minimizes inflammation at the cellular level, whether or not it results in meaningful improvements in post-surgical orthopedic outcomes remains unclear. Table 1 reflects a dearth of evidence to support the widespread current practice of cold therapy following orthopedic procedures, but few studies could demonstrate a significant difference in the analgesic use, VAS score, or ROM between cryotherapy and control groups. It is worth noting that these studies used different cryotherapy systems. Though in theory the continuous flow cryotherapy systems are similarly designed, there are potential differences among them that have not been controlled for in this analysis. All studies had <90 participants and focused on a single joint or procedure, making it difficult to draw large scale conclusions about the utility of cold therapy in the postoperative orthopedic population at large. Furthermore, researchers measured endpoints at a range of time intervals that were inconsistent across studies. In some cases, the significance of the impact of cryotherapy on recovery within a single study differed based on the time point at which researchers measured outcomes.^12-14 This raises the question as to whether cryotherapy has no benefits, or whether they are simply time-dependent. Future studies should seek to ascertain whether there is a postoperative time window in which cryotherapy could potentially expedite the recovery process.

Similarly, Table 2 shows a lack of consensus regarding the effect of advanced cryotherapy when compared to traditional ice application on pain, analgesic use, and joint mobility after surgery. However, all but 1 of these studies focused on knee procedures. Therefore, our findings may not be applicable to orthopedic surgeries on other joints. Nevertheless, the use of advanced cryotherapy in postoperative orthopedic care may wane if researchers continue to show that it is no more beneficial than its far less expensive counterpart of ice and an ace bandage.

The case studies discussed in this review serve as cautionary tales of the dangers of cryotherapy when used improperly. Though frostbite and subsequent tissue necrosis seem most common, physicians should be made aware that compartment syndrome and perniosis are also possible consequences. Orthopedic patients perhaps have an increased risk of developing these side effects due to the nature of their injuries and the large cutaneous surface area to which cryotherapy is applied. These outcomes could seemingly be avoided with improved educational initiatives targeted at both healthcare personnel and patients. Orthopedic surgeons might consider adding a short, instructive video focusing on proper usage as well as signs of adverse events to their discharge protocol to limit occurrences of these pitfalls associated with cryotherapy.

CONCLUSION

There is inadequate literature to support the of use postoperative cryotherapy of any kind in the field of orthopedics at this time. More robust, standardized studies, and a formidable economic analysis of advanced cold therapy systems are necessary before physicians prescribing cryotherapy can be confident that they are augmenting patient recovery. Nevertheless, as new developments in medicinal cryotherapy occur, it may be possible for the orthopedic community to wield its salutatory effects to limit complications and improve post-surgical outcomes.

ABSTRACT

Despite advancements in surgical technique and understanding of throwing mechanics, controversy persists regarding the treatment of grade III acromioclavicular (AC) joint separations, particularly in throwing athletes. Twenty-eight major league baseball (MLB) orthopedic team physicians were surveyed to determine their definitive management of a grade III AC separation in the dominant arm of a professional baseball pitcher and their experience treating AC joint separations in starting pitchers and position players. Return-to-play outcomes were also evaluated. Twenty (71.4%) team physicians recommended nonoperative intervention compared to 8 (28.6%) who would have operated acutely. Eighteen (64.3%) team physicians had treated at least 1 professional pitcher with a grade III AC separation; 51 (77.3%) pitchers had been treated nonoperatively compared to 15 (22.7%) operatively. No difference was observed in the proportion of pitchers who returned to the same level of play (P = .54), had full, unrestricted range of motion (P = .23), or had full pain relief (P = .19) between the operatively and nonoperatively treated MLB pitchers. The majority (53.6%) of physicians would not include an injection if the injury was treated nonoperatively. Open coracoclavicular reconstruction (65.2%) was preferred for operative cases; 66.7% of surgeons would also include distal clavicle excision as an adjunct procedure. About 90% of physicians would return pitchers to throwing >12 weeks after surgery compared to after 4 to 6 weeks in nonoperatively treated cases. In conclusion, MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in professional pitchers. If operative intervention is required, ligament reconstruction with adjunct distal clavicle excision were the most commonly performed procedures.

Continue to: Despite advancements in surgucal technique...

Despite advancements in surgical technique and improved understanding of the physiology of throwing mechanics, controversy persists regarding the preferred treatment for grade III acromioclavicular (AC) joint separations.^1-6 Nonsurgical management has demonstrated return to prior function with fewer complications.⁷ However, there is a growing body of evidence demonstrating that surgical intervention is associated with more favorable outcomes⁸ and should be considered in patients who place high functional demands on their shoulders.⁹

The reported results on professional athletes in the literature remain ambivalent. Multiple small case reports/series have reported successful nonoperative treatment of elite athletes.^10-12 Not surprisingly, McFarland and colleagues¹³ reported in 1997 that 69% of major league baseball (MLB) team physicians preferred nonoperative treatment for a theoretical starting pitcher sustaining a grade III AC separation 1 week prior to the start of the season. In contrast, reports of an inability to throw at a pre-injury level are equally commonplace.^14,15 Nevertheless, all of these studies were limited to small cohorts, as the incidence of grade III AC separations in elite throwing athletes is relatively uncommon.^13,16

In this study, we re-evaluated the study performed by McFarland and colleagues¹³ in 1997 by surveying all active MLB team orthopedic surgeons. We asked them how they would treat a grade III AC separation in a starting professional baseball pitcher. The physicians were also asked about their personal experience evaluating outcomes in these elite athletes. Given our improved understanding of the anatomy, pathophysiology, and surgical techniques for treating grade III AC separations, we hypothesize that more MLB team physicians would favor operative intervention treatment in professional baseball pitchers, as their vocation places higher demands on their shoulders.

MATERIALS AND METHODS

A questionnaire (Appendix A) was distributed to the team physicians of all 30 MLB teams. In addition to surgeon demographics, including age, years in practice, and years of taking care of an MLB team, the initial section of the questionnaire asked orthopedic surgeons how they would treat a theoretical starting pitcher who sustained a grade III AC joint separation of the dominant throwing arm 1 week prior to the start of the season. Physicians who preferred nonoperative treatment were asked whether they would use an injection (and what type), as well as when they would allow the pitcher to start a progressive interval throwing program. Physicians who preferred operative treatment were asked to rank their indications for operating, what procedure they would use (eg, open vs arthroscopic or coracoclavicular ligament repair vs reconstruction), and whether the surgical intervention would include distal clavicle excision. Both groups of physicians were also asked if their preferred treatment would change if the injury were to occur at the end of the season.

The second portion of the questionnaire asked surgeons about their experience treating AC joint separations in both starting pitchers and position players, as well as to describe the long-term outcomes of their preferred treatment, including time to return to full clearance for pitching, whether their patients returned to their prior level of play, and whether these patients had full pain relief. Finally, physicians were asked if any of the nonoperatively treated players ultimately crossed over and required operative intervention.

Continue to: Statistics...

STATISTICS

Descriptive statistics were used for continuous variables, and frequencies were used for categorical variables. Linear regression was performed to determine the correlation between the physician’s training or experience in treating AC joint separations and their recommended treatment. Fischer’s exact test/chi-square analysis was used to compare categorical variables. All tests were conducted using 2-sided hypothesis testing with statistical significance set at P < .05. All statistical analyses were conducted with SPSS 21.0 software (IBM Corporation).

RESULTS

A total of 28 MLB team physicians completed the questionnaires from 18 of the 30 MLB teams. The average age of the responders was 50.5 years (range, 34-60 years), with an average of 18.2 years in practice (range, 2-30 years) and 10.8 years (range, 1-24 years) taking care of their current professional baseball team. About 82% of the team physicians completed a sports medicine fellowship. On average, physicians saw 16.6 (range, 5-50) grade III or higher AC joint separations per year, and operated on 4.6 (range, 0-10) per year.

Nonoperative treatment was the preferred treatment for a grade III AC joint separation in a starting professional baseball pitcher for the majority of team physicians (20/28). No correlation was observed between the physician’s age (P = .881), years in practice (P = .915), years taking care of their professional team (P = .989), percentage of practice focused on shoulders (P = .986), number of AC joint injuries seen (P = .325), or number of surgeries performed per year (P = .807) with the team physician’s preferred treatment. Compared to the proportion reported originally by McFarland and colleagues¹³ in 1997 (69%), there was no difference in the proportion of team physicians that recommended nonoperative treatment (P = 1).

If treating this injury nonoperatively, 46.4% of physicians would also use an injection, with orthobiologics (eg, platelet-rich plasma) as the most popular choice (Table 1). No consensus was provided on the timeframe to return pitchers back to a progressive interval throwing program; however, 46.67% of physicians would return pitchers 4 to 6 weeks after a nonoperatively treated injury, while 35.7% would return pitchers 7 to 12 weeks after the initial injury.

Table 1. Treatment Preferences of Grade III AC Separation by MLB Team Physicians

^aRespondents were allowed to choose more than 1 treatment in each category. ^bChosen as an adjunct treatment.

Abbreviations: AC, acromioclavicular; MLB, major league baseball.

Most physicians (64.3%) cited functional limitations as the most important reason for indicating operative treatment, followed by pain (21.4%), and a deformity (14.3%). About 65% preferred open coracoclavicular ligament reconstruction. No physician recommended the Weaver-Dunn procedure or use of hardware (eg, hook plate). Of those who preferred an operative intervention, 66.7% would also include a distal clavicle excision, which is significantly higher than the proportion reported by McFarland and colleagues¹³ (23%, P = .0170). About 90% of physicians would return pitchers to play >12 weeks after operative treatment.

Continue to: If the injury occurred at the end ...

If the injury occurred at the end of the season, 7 of the 20 orthopedists (35%) who recommended nonoperative treatment said they would change to an operative intervention. Eighteen of 28 responders would have the same algorithm for MLB position players. Team physicians were less likely to recommend operative intervention in position players due to less demand on the arm and increased ability to accommodate the injury by altering their throwing mechanics.

Eighteen (64%) of the team physicians had treated at least 1 professional pitcher with a grade III AC separation in his dominant arm, and 11 (39.3%) had treated >1. Collectively, team physicians had treated 15 professional pitchers operatively, and 51 nonoperatively; only 3 patients converted to operative intervention after a failed nonoperative treatment.

Of the pitchers treated operatively, 93.3% (14) of pitchers returned to their prior level of pitching. The 1 patient who failed to return to the same level of pitching retired instead of returning to play. About 80% (12) of the pitchers had full pain relief, and 93.3% (14) had full range of motion (ROM). The pitcher who failed to regain full ROM also had a concomitant rotator cuff repair. The only complication reported from an operative intervention was a pitcher who sustained a coracoid fracture 10 months postoperatively while throwing 100 mph. Of the pitchers treated nonoperatively, 96% returned to their prior level of pitching, 92.2% (47) had full complete pain relief when throwing, and 100% had full ROM. No differences were observed between the proportion of pitchers who returned to their prior level of pitching, regained full ROM, or had full pain relief in the operative and nonoperative groups (Table 2).

Table 2. Outcomes of Treatment of Grade III AC Separation in 58 Professional Baseball Players

Abbreviations: AC, acromioclavicular; ROM, range of motion.

DISCUSSION 

Controversy persists regarding the optimal management of acute grade III AC separations, with the current available evidence potentially suggesting better cosmetic and radiological results but no definite differences in clinical results.^1-6,17,18 In the absence of formal clinical practice guidelines, surgeons rely on their own experience or defer to the anecdotal experience of experts in the field. Our initial hypothesis was false in this survey of MLB team physicians taking care of overhead throwing athletes at the highest level. Our results demonstrate that despite improved techniques and an increased understanding of the pathophysiology of AC joint separations, conservative management is still the preferred treatment for acute grade III AC joint separations in professional baseball pitchers. The proportion of team physicians recommending nonoperative treatment in our series was essentially equivalent to the results reported by McFarland and colleagues¹³ in 1997, suggesting that the pendulum continues to favor conservative management initially. This status quo likely reflects both the dearth of literature suggesting a substantial benefit of acute operative repair, as well as the ability to accommodate with conservative measures after most grade III AC injuries, even at the highest level of athletic competition.

These results are also consistent with trends from the last few decades. In the 1970s, the overwhelming preference for treating an acute complete AC joint separation was surgical repair, with Powers and Bach¹⁰ reporting in a 1974 survey of 163 chairmen of orthopedic programs around the country that 91.5% advocated surgical treatment. However, surgical preference had reversed by the 1990s. Of the 187 chairmen and 59 team physicians surveyed by Cox¹⁹ in 1992, 72% and 86% respectively preferred nonoperative treatment in a theoretical 21-year-old athlete with a grade III AC separation. Nissen and Chatterjee²⁰ reported in 2007 on a survey of all American Orthopaedic Society for Sports Medicine surgeons (N = 577) and Accreditation Council for Graduate Medical Education orthopedic program residency directors (N = 87) that >80% of responders preferred conservative measures for this acute injury. The reversal of trends has also been corroborated by recent multicenter trials demonstrating no difference in clinical outcomes between operative and nonoperative treatment of high grade AC joint dislocations, albeit these patients were not all high level overhead throwing athletes.^17,18

Continue to: The trends in surgical interventions are notable...

The trends in surgical interventions are notable within the smaller subset of patients who are indicated for operative repair. Use of hardware and primary ligament repair, while popular in the surveys conducted in the 1970s¹⁰ and 1990s¹³ and even present in Nissen and Chatterjee’s²⁰ 2007 survey, were noticeably absent from our survey results, with the majority of respondents preferring open coracoclavicular ligament reconstruction. The role of distal clavicle excision has also expanded, from 23% of team physicians recommending it in 1997¹³ to 57% to 59% in Nissen and Chatterjee’s²⁰ 2007 survey, to 66.7% in our series. This trend is not surprising as several recent cadaveric biomechanical studies have demonstrated that not only do peak graft forces not increase significantly,²¹ the anterior-posterior and superior-inferior motion at the AC joint following ligament reconstruction is maintained despite resection of the lateral clavicle.²² Additionally, primary distal clavicle excision may prevent the development of post-traumatic arthritis at the AC joint and osteolysis of the distal clavicle as a possible pain generator in the future.²³ However, some respondents cautioned against performing a concomitant distal clavicle excision, as some biomechanical data demonstrate that resecting the distal clavicle may lead to increased horizontal translation at the AC joint despite intact superior and posterior AC capsules.²⁴ Professional baseball pitchers may also be more lax and thus prone to more instability. Primary repair or reconstruction may not always lead to complete pre-injury stability in these individuals. This subtle unrecognized instability is hard to diagnosis and may be a persistent source of pain; thus, adding a distal clavicle excision may actually exacerbate the instability.

The nuanced indications for operative intervention, such as the presence of associated lesions were not captured by our survey.²⁵ While most team physicians cited functional limitations as their most common reason for offering surgery, several MLB orthopedic surgeons also commented on evaluating the stability of the AC joint after a grade III injury, akin to the consensus statement from the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) Upper Extremity Committee²⁶ in 2014 that diversified the Rockwood Grade III AC joint separation into its IIIA and IIIB classifications. The ISAKOS recommendations include initial conservative management and a second evaluation (both clinical and radiographic) for grade III lesions 3 to 6 weeks after the injury. However, as professional baseball is an incredibly profitable sport with an annual revenue approaching $9.5 billion²⁷ and pitching salaries up to $32.5 million in 2015, serious financial considerations must be given to players who wish to avoid undergoing delayed surgery.

This study has shortcomings typical of expert opinion papers. The retrospective nature of this study places the data at risk of recall bias. Objective data (eg, terminal ROM, pain relief, and return to play) were obtained from a retrospective chart review; however, no standard documentation or collection method was used given the number of surgeons involved and, thus, conclusions based on treatment outcomes are imperfect. Another major weakness of this survey is the relatively small number of patients and respondents. An a priori power analysis was not available, as this was a retrospective review. A comparative trial will be necessary to definitively support one treatment over another. Assuming a 95% return to play in the nonoperatively treated group, approximately 300 patients would be needed in a prospective 2-armed study with 80% power to detect a 10% reduction in the incidence of return to play using an alpha level of 0.05 and assuming no loss to follow-up. This sample size would be difficult to achieve in this patient population.

However, compared to past series,¹³ the number of professional baseball players treated by the collective experience of these MLB team physicians is the largest reported to date. As suggested above, the rarity of this condition in elite athletes precludes the ability to have matched controls to definitively determine the optimal treatment, which may explain the lack of difference in the return to play, ROM, and pain relief outcomes. Instead, we can only extrapolate based on the collective anecdotal experience of the MLB team physicians.

CONCLUSION

Despite advances in surgical technique and understanding of throwing mechanics, the majority of MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in a professional baseball pitcher. Open coracoclavicular ligament reconstruction was preferred for those who preferred operative intervention. An increasing number of orthopedic surgeons now consider a distal clavicle excision as an adjunct procedure.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

Despite advancements in surgical technique and understanding of throwing mechanics, controversy persists regarding the treatment of grade III acromioclavicular (AC) joint separations, particularly in throwing athletes. Twenty-eight major league baseball (MLB) orthopedic team physicians were surveyed to determine their definitive management of a grade III AC separation in the dominant arm of a professional baseball pitcher and their experience treating AC joint separations in starting pitchers and position players. Return-to-play outcomes were also evaluated. Twenty (71.4%) team physicians recommended nonoperative intervention compared to 8 (28.6%) who would have operated acutely. Eighteen (64.3%) team physicians had treated at least 1 professional pitcher with a grade III AC separation; 51 (77.3%) pitchers had been treated nonoperatively compared to 15 (22.7%) operatively. No difference was observed in the proportion of pitchers who returned to the same level of play (P = .54), had full, unrestricted range of motion (P = .23), or had full pain relief (P = .19) between the operatively and nonoperatively treated MLB pitchers. The majority (53.6%) of physicians would not include an injection if the injury was treated nonoperatively. Open coracoclavicular reconstruction (65.2%) was preferred for operative cases; 66.7% of surgeons would also include distal clavicle excision as an adjunct procedure. About 90% of physicians would return pitchers to throwing >12 weeks after surgery compared to after 4 to 6 weeks in nonoperatively treated cases. In conclusion, MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in professional pitchers. If operative intervention is required, ligament reconstruction with adjunct distal clavicle excision were the most commonly performed procedures.

Continue to: Despite advancements in surgucal technique...

Despite advancements in surgical technique and improved understanding of the physiology of throwing mechanics, controversy persists regarding the preferred treatment for grade III acromioclavicular (AC) joint separations.^1-6 Nonsurgical management has demonstrated return to prior function with fewer complications.⁷ However, there is a growing body of evidence demonstrating that surgical intervention is associated with more favorable outcomes⁸ and should be considered in patients who place high functional demands on their shoulders.⁹

The reported results on professional athletes in the literature remain ambivalent. Multiple small case reports/series have reported successful nonoperative treatment of elite athletes.^10-12 Not surprisingly, McFarland and colleagues¹³ reported in 1997 that 69% of major league baseball (MLB) team physicians preferred nonoperative treatment for a theoretical starting pitcher sustaining a grade III AC separation 1 week prior to the start of the season. In contrast, reports of an inability to throw at a pre-injury level are equally commonplace.^14,15 Nevertheless, all of these studies were limited to small cohorts, as the incidence of grade III AC separations in elite throwing athletes is relatively uncommon.^13,16

In this study, we re-evaluated the study performed by McFarland and colleagues¹³ in 1997 by surveying all active MLB team orthopedic surgeons. We asked them how they would treat a grade III AC separation in a starting professional baseball pitcher. The physicians were also asked about their personal experience evaluating outcomes in these elite athletes. Given our improved understanding of the anatomy, pathophysiology, and surgical techniques for treating grade III AC separations, we hypothesize that more MLB team physicians would favor operative intervention treatment in professional baseball pitchers, as their vocation places higher demands on their shoulders.

MATERIALS AND METHODS

A questionnaire (Appendix A) was distributed to the team physicians of all 30 MLB teams. In addition to surgeon demographics, including age, years in practice, and years of taking care of an MLB team, the initial section of the questionnaire asked orthopedic surgeons how they would treat a theoretical starting pitcher who sustained a grade III AC joint separation of the dominant throwing arm 1 week prior to the start of the season. Physicians who preferred nonoperative treatment were asked whether they would use an injection (and what type), as well as when they would allow the pitcher to start a progressive interval throwing program. Physicians who preferred operative treatment were asked to rank their indications for operating, what procedure they would use (eg, open vs arthroscopic or coracoclavicular ligament repair vs reconstruction), and whether the surgical intervention would include distal clavicle excision. Both groups of physicians were also asked if their preferred treatment would change if the injury were to occur at the end of the season.

The second portion of the questionnaire asked surgeons about their experience treating AC joint separations in both starting pitchers and position players, as well as to describe the long-term outcomes of their preferred treatment, including time to return to full clearance for pitching, whether their patients returned to their prior level of play, and whether these patients had full pain relief. Finally, physicians were asked if any of the nonoperatively treated players ultimately crossed over and required operative intervention.

Continue to: Statistics...

STATISTICS

Descriptive statistics were used for continuous variables, and frequencies were used for categorical variables. Linear regression was performed to determine the correlation between the physician’s training or experience in treating AC joint separations and their recommended treatment. Fischer’s exact test/chi-square analysis was used to compare categorical variables. All tests were conducted using 2-sided hypothesis testing with statistical significance set at P < .05. All statistical analyses were conducted with SPSS 21.0 software (IBM Corporation).

RESULTS

A total of 28 MLB team physicians completed the questionnaires from 18 of the 30 MLB teams. The average age of the responders was 50.5 years (range, 34-60 years), with an average of 18.2 years in practice (range, 2-30 years) and 10.8 years (range, 1-24 years) taking care of their current professional baseball team. About 82% of the team physicians completed a sports medicine fellowship. On average, physicians saw 16.6 (range, 5-50) grade III or higher AC joint separations per year, and operated on 4.6 (range, 0-10) per year.

Nonoperative treatment was the preferred treatment for a grade III AC joint separation in a starting professional baseball pitcher for the majority of team physicians (20/28). No correlation was observed between the physician’s age (P = .881), years in practice (P = .915), years taking care of their professional team (P = .989), percentage of practice focused on shoulders (P = .986), number of AC joint injuries seen (P = .325), or number of surgeries performed per year (P = .807) with the team physician’s preferred treatment. Compared to the proportion reported originally by McFarland and colleagues¹³ in 1997 (69%), there was no difference in the proportion of team physicians that recommended nonoperative treatment (P = 1).

If treating this injury nonoperatively, 46.4% of physicians would also use an injection, with orthobiologics (eg, platelet-rich plasma) as the most popular choice (Table 1). No consensus was provided on the timeframe to return pitchers back to a progressive interval throwing program; however, 46.67% of physicians would return pitchers 4 to 6 weeks after a nonoperatively treated injury, while 35.7% would return pitchers 7 to 12 weeks after the initial injury.

Table 1. Treatment Preferences of Grade III AC Separation by MLB Team Physicians

^aRespondents were allowed to choose more than 1 treatment in each category. ^bChosen as an adjunct treatment.

Abbreviations: AC, acromioclavicular; MLB, major league baseball.

Most physicians (64.3%) cited functional limitations as the most important reason for indicating operative treatment, followed by pain (21.4%), and a deformity (14.3%). About 65% preferred open coracoclavicular ligament reconstruction. No physician recommended the Weaver-Dunn procedure or use of hardware (eg, hook plate). Of those who preferred an operative intervention, 66.7% would also include a distal clavicle excision, which is significantly higher than the proportion reported by McFarland and colleagues¹³ (23%, P = .0170). About 90% of physicians would return pitchers to play >12 weeks after operative treatment.

Continue to: If the injury occurred at the end ...

If the injury occurred at the end of the season, 7 of the 20 orthopedists (35%) who recommended nonoperative treatment said they would change to an operative intervention. Eighteen of 28 responders would have the same algorithm for MLB position players. Team physicians were less likely to recommend operative intervention in position players due to less demand on the arm and increased ability to accommodate the injury by altering their throwing mechanics.

Eighteen (64%) of the team physicians had treated at least 1 professional pitcher with a grade III AC separation in his dominant arm, and 11 (39.3%) had treated >1. Collectively, team physicians had treated 15 professional pitchers operatively, and 51 nonoperatively; only 3 patients converted to operative intervention after a failed nonoperative treatment.

Of the pitchers treated operatively, 93.3% (14) of pitchers returned to their prior level of pitching. The 1 patient who failed to return to the same level of pitching retired instead of returning to play. About 80% (12) of the pitchers had full pain relief, and 93.3% (14) had full range of motion (ROM). The pitcher who failed to regain full ROM also had a concomitant rotator cuff repair. The only complication reported from an operative intervention was a pitcher who sustained a coracoid fracture 10 months postoperatively while throwing 100 mph. Of the pitchers treated nonoperatively, 96% returned to their prior level of pitching, 92.2% (47) had full complete pain relief when throwing, and 100% had full ROM. No differences were observed between the proportion of pitchers who returned to their prior level of pitching, regained full ROM, or had full pain relief in the operative and nonoperative groups (Table 2).

Table 2. Outcomes of Treatment of Grade III AC Separation in 58 Professional Baseball Players

Abbreviations: AC, acromioclavicular; ROM, range of motion.

DISCUSSION 

Controversy persists regarding the optimal management of acute grade III AC separations, with the current available evidence potentially suggesting better cosmetic and radiological results but no definite differences in clinical results.^1-6,17,18 In the absence of formal clinical practice guidelines, surgeons rely on their own experience or defer to the anecdotal experience of experts in the field. Our initial hypothesis was false in this survey of MLB team physicians taking care of overhead throwing athletes at the highest level. Our results demonstrate that despite improved techniques and an increased understanding of the pathophysiology of AC joint separations, conservative management is still the preferred treatment for acute grade III AC joint separations in professional baseball pitchers. The proportion of team physicians recommending nonoperative treatment in our series was essentially equivalent to the results reported by McFarland and colleagues¹³ in 1997, suggesting that the pendulum continues to favor conservative management initially. This status quo likely reflects both the dearth of literature suggesting a substantial benefit of acute operative repair, as well as the ability to accommodate with conservative measures after most grade III AC injuries, even at the highest level of athletic competition.

These results are also consistent with trends from the last few decades. In the 1970s, the overwhelming preference for treating an acute complete AC joint separation was surgical repair, with Powers and Bach¹⁰ reporting in a 1974 survey of 163 chairmen of orthopedic programs around the country that 91.5% advocated surgical treatment. However, surgical preference had reversed by the 1990s. Of the 187 chairmen and 59 team physicians surveyed by Cox¹⁹ in 1992, 72% and 86% respectively preferred nonoperative treatment in a theoretical 21-year-old athlete with a grade III AC separation. Nissen and Chatterjee²⁰ reported in 2007 on a survey of all American Orthopaedic Society for Sports Medicine surgeons (N = 577) and Accreditation Council for Graduate Medical Education orthopedic program residency directors (N = 87) that >80% of responders preferred conservative measures for this acute injury. The reversal of trends has also been corroborated by recent multicenter trials demonstrating no difference in clinical outcomes between operative and nonoperative treatment of high grade AC joint dislocations, albeit these patients were not all high level overhead throwing athletes.^17,18

Continue to: The trends in surgical interventions are notable...

The trends in surgical interventions are notable within the smaller subset of patients who are indicated for operative repair. Use of hardware and primary ligament repair, while popular in the surveys conducted in the 1970s¹⁰ and 1990s¹³ and even present in Nissen and Chatterjee’s²⁰ 2007 survey, were noticeably absent from our survey results, with the majority of respondents preferring open coracoclavicular ligament reconstruction. The role of distal clavicle excision has also expanded, from 23% of team physicians recommending it in 1997¹³ to 57% to 59% in Nissen and Chatterjee’s²⁰ 2007 survey, to 66.7% in our series. This trend is not surprising as several recent cadaveric biomechanical studies have demonstrated that not only do peak graft forces not increase significantly,²¹ the anterior-posterior and superior-inferior motion at the AC joint following ligament reconstruction is maintained despite resection of the lateral clavicle.²² Additionally, primary distal clavicle excision may prevent the development of post-traumatic arthritis at the AC joint and osteolysis of the distal clavicle as a possible pain generator in the future.²³ However, some respondents cautioned against performing a concomitant distal clavicle excision, as some biomechanical data demonstrate that resecting the distal clavicle may lead to increased horizontal translation at the AC joint despite intact superior and posterior AC capsules.²⁴ Professional baseball pitchers may also be more lax and thus prone to more instability. Primary repair or reconstruction may not always lead to complete pre-injury stability in these individuals. This subtle unrecognized instability is hard to diagnosis and may be a persistent source of pain; thus, adding a distal clavicle excision may actually exacerbate the instability.

The nuanced indications for operative intervention, such as the presence of associated lesions were not captured by our survey.²⁵ While most team physicians cited functional limitations as their most common reason for offering surgery, several MLB orthopedic surgeons also commented on evaluating the stability of the AC joint after a grade III injury, akin to the consensus statement from the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) Upper Extremity Committee²⁶ in 2014 that diversified the Rockwood Grade III AC joint separation into its IIIA and IIIB classifications. The ISAKOS recommendations include initial conservative management and a second evaluation (both clinical and radiographic) for grade III lesions 3 to 6 weeks after the injury. However, as professional baseball is an incredibly profitable sport with an annual revenue approaching $9.5 billion²⁷ and pitching salaries up to $32.5 million in 2015, serious financial considerations must be given to players who wish to avoid undergoing delayed surgery.

This study has shortcomings typical of expert opinion papers. The retrospective nature of this study places the data at risk of recall bias. Objective data (eg, terminal ROM, pain relief, and return to play) were obtained from a retrospective chart review; however, no standard documentation or collection method was used given the number of surgeons involved and, thus, conclusions based on treatment outcomes are imperfect. Another major weakness of this survey is the relatively small number of patients and respondents. An a priori power analysis was not available, as this was a retrospective review. A comparative trial will be necessary to definitively support one treatment over another. Assuming a 95% return to play in the nonoperatively treated group, approximately 300 patients would be needed in a prospective 2-armed study with 80% power to detect a 10% reduction in the incidence of return to play using an alpha level of 0.05 and assuming no loss to follow-up. This sample size would be difficult to achieve in this patient population.

However, compared to past series,¹³ the number of professional baseball players treated by the collective experience of these MLB team physicians is the largest reported to date. As suggested above, the rarity of this condition in elite athletes precludes the ability to have matched controls to definitively determine the optimal treatment, which may explain the lack of difference in the return to play, ROM, and pain relief outcomes. Instead, we can only extrapolate based on the collective anecdotal experience of the MLB team physicians.

CONCLUSION

Despite advances in surgical technique and understanding of throwing mechanics, the majority of MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in a professional baseball pitcher. Open coracoclavicular ligament reconstruction was preferred for those who preferred operative intervention. An increasing number of orthopedic surgeons now consider a distal clavicle excision as an adjunct procedure.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

Despite advancements in surgical technique and understanding of throwing mechanics, controversy persists regarding the treatment of grade III acromioclavicular (AC) joint separations, particularly in throwing athletes. Twenty-eight major league baseball (MLB) orthopedic team physicians were surveyed to determine their definitive management of a grade III AC separation in the dominant arm of a professional baseball pitcher and their experience treating AC joint separations in starting pitchers and position players. Return-to-play outcomes were also evaluated. Twenty (71.4%) team physicians recommended nonoperative intervention compared to 8 (28.6%) who would have operated acutely. Eighteen (64.3%) team physicians had treated at least 1 professional pitcher with a grade III AC separation; 51 (77.3%) pitchers had been treated nonoperatively compared to 15 (22.7%) operatively. No difference was observed in the proportion of pitchers who returned to the same level of play (P = .54), had full, unrestricted range of motion (P = .23), or had full pain relief (P = .19) between the operatively and nonoperatively treated MLB pitchers. The majority (53.6%) of physicians would not include an injection if the injury was treated nonoperatively. Open coracoclavicular reconstruction (65.2%) was preferred for operative cases; 66.7% of surgeons would also include distal clavicle excision as an adjunct procedure. About 90% of physicians would return pitchers to throwing >12 weeks after surgery compared to after 4 to 6 weeks in nonoperatively treated cases. In conclusion, MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in professional pitchers. If operative intervention is required, ligament reconstruction with adjunct distal clavicle excision were the most commonly performed procedures.

Continue to: Despite advancements in surgucal technique...

Despite advancements in surgical technique and improved understanding of the physiology of throwing mechanics, controversy persists regarding the preferred treatment for grade III acromioclavicular (AC) joint separations.^1-6 Nonsurgical management has demonstrated return to prior function with fewer complications.⁷ However, there is a growing body of evidence demonstrating that surgical intervention is associated with more favorable outcomes⁸ and should be considered in patients who place high functional demands on their shoulders.⁹

The reported results on professional athletes in the literature remain ambivalent. Multiple small case reports/series have reported successful nonoperative treatment of elite athletes.^10-12 Not surprisingly, McFarland and colleagues¹³ reported in 1997 that 69% of major league baseball (MLB) team physicians preferred nonoperative treatment for a theoretical starting pitcher sustaining a grade III AC separation 1 week prior to the start of the season. In contrast, reports of an inability to throw at a pre-injury level are equally commonplace.^14,15 Nevertheless, all of these studies were limited to small cohorts, as the incidence of grade III AC separations in elite throwing athletes is relatively uncommon.^13,16

In this study, we re-evaluated the study performed by McFarland and colleagues¹³ in 1997 by surveying all active MLB team orthopedic surgeons. We asked them how they would treat a grade III AC separation in a starting professional baseball pitcher. The physicians were also asked about their personal experience evaluating outcomes in these elite athletes. Given our improved understanding of the anatomy, pathophysiology, and surgical techniques for treating grade III AC separations, we hypothesize that more MLB team physicians would favor operative intervention treatment in professional baseball pitchers, as their vocation places higher demands on their shoulders.

MATERIALS AND METHODS

A questionnaire (Appendix A) was distributed to the team physicians of all 30 MLB teams. In addition to surgeon demographics, including age, years in practice, and years of taking care of an MLB team, the initial section of the questionnaire asked orthopedic surgeons how they would treat a theoretical starting pitcher who sustained a grade III AC joint separation of the dominant throwing arm 1 week prior to the start of the season. Physicians who preferred nonoperative treatment were asked whether they would use an injection (and what type), as well as when they would allow the pitcher to start a progressive interval throwing program. Physicians who preferred operative treatment were asked to rank their indications for operating, what procedure they would use (eg, open vs arthroscopic or coracoclavicular ligament repair vs reconstruction), and whether the surgical intervention would include distal clavicle excision. Both groups of physicians were also asked if their preferred treatment would change if the injury were to occur at the end of the season.

The second portion of the questionnaire asked surgeons about their experience treating AC joint separations in both starting pitchers and position players, as well as to describe the long-term outcomes of their preferred treatment, including time to return to full clearance for pitching, whether their patients returned to their prior level of play, and whether these patients had full pain relief. Finally, physicians were asked if any of the nonoperatively treated players ultimately crossed over and required operative intervention.

Continue to: Statistics...

STATISTICS

Descriptive statistics were used for continuous variables, and frequencies were used for categorical variables. Linear regression was performed to determine the correlation between the physician’s training or experience in treating AC joint separations and their recommended treatment. Fischer’s exact test/chi-square analysis was used to compare categorical variables. All tests were conducted using 2-sided hypothesis testing with statistical significance set at P < .05. All statistical analyses were conducted with SPSS 21.0 software (IBM Corporation).

RESULTS

A total of 28 MLB team physicians completed the questionnaires from 18 of the 30 MLB teams. The average age of the responders was 50.5 years (range, 34-60 years), with an average of 18.2 years in practice (range, 2-30 years) and 10.8 years (range, 1-24 years) taking care of their current professional baseball team. About 82% of the team physicians completed a sports medicine fellowship. On average, physicians saw 16.6 (range, 5-50) grade III or higher AC joint separations per year, and operated on 4.6 (range, 0-10) per year.

Nonoperative treatment was the preferred treatment for a grade III AC joint separation in a starting professional baseball pitcher for the majority of team physicians (20/28). No correlation was observed between the physician’s age (P = .881), years in practice (P = .915), years taking care of their professional team (P = .989), percentage of practice focused on shoulders (P = .986), number of AC joint injuries seen (P = .325), or number of surgeries performed per year (P = .807) with the team physician’s preferred treatment. Compared to the proportion reported originally by McFarland and colleagues¹³ in 1997 (69%), there was no difference in the proportion of team physicians that recommended nonoperative treatment (P = 1).

If treating this injury nonoperatively, 46.4% of physicians would also use an injection, with orthobiologics (eg, platelet-rich plasma) as the most popular choice (Table 1). No consensus was provided on the timeframe to return pitchers back to a progressive interval throwing program; however, 46.67% of physicians would return pitchers 4 to 6 weeks after a nonoperatively treated injury, while 35.7% would return pitchers 7 to 12 weeks after the initial injury.

Table 1. Treatment Preferences of Grade III AC Separation by MLB Team Physicians

^aRespondents were allowed to choose more than 1 treatment in each category. ^bChosen as an adjunct treatment.

Abbreviations: AC, acromioclavicular; MLB, major league baseball.

Most physicians (64.3%) cited functional limitations as the most important reason for indicating operative treatment, followed by pain (21.4%), and a deformity (14.3%). About 65% preferred open coracoclavicular ligament reconstruction. No physician recommended the Weaver-Dunn procedure or use of hardware (eg, hook plate). Of those who preferred an operative intervention, 66.7% would also include a distal clavicle excision, which is significantly higher than the proportion reported by McFarland and colleagues¹³ (23%, P = .0170). About 90% of physicians would return pitchers to play >12 weeks after operative treatment.

Continue to: If the injury occurred at the end ...

If the injury occurred at the end of the season, 7 of the 20 orthopedists (35%) who recommended nonoperative treatment said they would change to an operative intervention. Eighteen of 28 responders would have the same algorithm for MLB position players. Team physicians were less likely to recommend operative intervention in position players due to less demand on the arm and increased ability to accommodate the injury by altering their throwing mechanics.

Eighteen (64%) of the team physicians had treated at least 1 professional pitcher with a grade III AC separation in his dominant arm, and 11 (39.3%) had treated >1. Collectively, team physicians had treated 15 professional pitchers operatively, and 51 nonoperatively; only 3 patients converted to operative intervention after a failed nonoperative treatment.

Of the pitchers treated operatively, 93.3% (14) of pitchers returned to their prior level of pitching. The 1 patient who failed to return to the same level of pitching retired instead of returning to play. About 80% (12) of the pitchers had full pain relief, and 93.3% (14) had full range of motion (ROM). The pitcher who failed to regain full ROM also had a concomitant rotator cuff repair. The only complication reported from an operative intervention was a pitcher who sustained a coracoid fracture 10 months postoperatively while throwing 100 mph. Of the pitchers treated nonoperatively, 96% returned to their prior level of pitching, 92.2% (47) had full complete pain relief when throwing, and 100% had full ROM. No differences were observed between the proportion of pitchers who returned to their prior level of pitching, regained full ROM, or had full pain relief in the operative and nonoperative groups (Table 2).

Table 2. Outcomes of Treatment of Grade III AC Separation in 58 Professional Baseball Players

Abbreviations: AC, acromioclavicular; ROM, range of motion.

DISCUSSION 

Controversy persists regarding the optimal management of acute grade III AC separations, with the current available evidence potentially suggesting better cosmetic and radiological results but no definite differences in clinical results.^1-6,17,18 In the absence of formal clinical practice guidelines, surgeons rely on their own experience or defer to the anecdotal experience of experts in the field. Our initial hypothesis was false in this survey of MLB team physicians taking care of overhead throwing athletes at the highest level. Our results demonstrate that despite improved techniques and an increased understanding of the pathophysiology of AC joint separations, conservative management is still the preferred treatment for acute grade III AC joint separations in professional baseball pitchers. The proportion of team physicians recommending nonoperative treatment in our series was essentially equivalent to the results reported by McFarland and colleagues¹³ in 1997, suggesting that the pendulum continues to favor conservative management initially. This status quo likely reflects both the dearth of literature suggesting a substantial benefit of acute operative repair, as well as the ability to accommodate with conservative measures after most grade III AC injuries, even at the highest level of athletic competition.

These results are also consistent with trends from the last few decades. In the 1970s, the overwhelming preference for treating an acute complete AC joint separation was surgical repair, with Powers and Bach¹⁰ reporting in a 1974 survey of 163 chairmen of orthopedic programs around the country that 91.5% advocated surgical treatment. However, surgical preference had reversed by the 1990s. Of the 187 chairmen and 59 team physicians surveyed by Cox¹⁹ in 1992, 72% and 86% respectively preferred nonoperative treatment in a theoretical 21-year-old athlete with a grade III AC separation. Nissen and Chatterjee²⁰ reported in 2007 on a survey of all American Orthopaedic Society for Sports Medicine surgeons (N = 577) and Accreditation Council for Graduate Medical Education orthopedic program residency directors (N = 87) that >80% of responders preferred conservative measures for this acute injury. The reversal of trends has also been corroborated by recent multicenter trials demonstrating no difference in clinical outcomes between operative and nonoperative treatment of high grade AC joint dislocations, albeit these patients were not all high level overhead throwing athletes.^17,18

Continue to: The trends in surgical interventions are notable...

The trends in surgical interventions are notable within the smaller subset of patients who are indicated for operative repair. Use of hardware and primary ligament repair, while popular in the surveys conducted in the 1970s¹⁰ and 1990s¹³ and even present in Nissen and Chatterjee’s²⁰ 2007 survey, were noticeably absent from our survey results, with the majority of respondents preferring open coracoclavicular ligament reconstruction. The role of distal clavicle excision has also expanded, from 23% of team physicians recommending it in 1997¹³ to 57% to 59% in Nissen and Chatterjee’s²⁰ 2007 survey, to 66.7% in our series. This trend is not surprising as several recent cadaveric biomechanical studies have demonstrated that not only do peak graft forces not increase significantly,²¹ the anterior-posterior and superior-inferior motion at the AC joint following ligament reconstruction is maintained despite resection of the lateral clavicle.²² Additionally, primary distal clavicle excision may prevent the development of post-traumatic arthritis at the AC joint and osteolysis of the distal clavicle as a possible pain generator in the future.²³ However, some respondents cautioned against performing a concomitant distal clavicle excision, as some biomechanical data demonstrate that resecting the distal clavicle may lead to increased horizontal translation at the AC joint despite intact superior and posterior AC capsules.²⁴ Professional baseball pitchers may also be more lax and thus prone to more instability. Primary repair or reconstruction may not always lead to complete pre-injury stability in these individuals. This subtle unrecognized instability is hard to diagnosis and may be a persistent source of pain; thus, adding a distal clavicle excision may actually exacerbate the instability.

The nuanced indications for operative intervention, such as the presence of associated lesions were not captured by our survey.²⁵ While most team physicians cited functional limitations as their most common reason for offering surgery, several MLB orthopedic surgeons also commented on evaluating the stability of the AC joint after a grade III injury, akin to the consensus statement from the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) Upper Extremity Committee²⁶ in 2014 that diversified the Rockwood Grade III AC joint separation into its IIIA and IIIB classifications. The ISAKOS recommendations include initial conservative management and a second evaluation (both clinical and radiographic) for grade III lesions 3 to 6 weeks after the injury. However, as professional baseball is an incredibly profitable sport with an annual revenue approaching $9.5 billion²⁷ and pitching salaries up to $32.5 million in 2015, serious financial considerations must be given to players who wish to avoid undergoing delayed surgery.

This study has shortcomings typical of expert opinion papers. The retrospective nature of this study places the data at risk of recall bias. Objective data (eg, terminal ROM, pain relief, and return to play) were obtained from a retrospective chart review; however, no standard documentation or collection method was used given the number of surgeons involved and, thus, conclusions based on treatment outcomes are imperfect. Another major weakness of this survey is the relatively small number of patients and respondents. An a priori power analysis was not available, as this was a retrospective review. A comparative trial will be necessary to definitively support one treatment over another. Assuming a 95% return to play in the nonoperatively treated group, approximately 300 patients would be needed in a prospective 2-armed study with 80% power to detect a 10% reduction in the incidence of return to play using an alpha level of 0.05 and assuming no loss to follow-up. This sample size would be difficult to achieve in this patient population.

However, compared to past series,¹³ the number of professional baseball players treated by the collective experience of these MLB team physicians is the largest reported to date. As suggested above, the rarity of this condition in elite athletes precludes the ability to have matched controls to definitively determine the optimal treatment, which may explain the lack of difference in the return to play, ROM, and pain relief outcomes. Instead, we can only extrapolate based on the collective anecdotal experience of the MLB team physicians.

CONCLUSION

Despite advances in surgical technique and understanding of throwing mechanics, the majority of MLB team physicians preferred nonoperative management for an acute grade III AC joint separation in a professional baseball pitcher. Open coracoclavicular ligament reconstruction was preferred for those who preferred operative intervention. An increasing number of orthopedic surgeons now consider a distal clavicle excision as an adjunct procedure.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

Blunt trauma to the anterior knee typically results in a contusion or fracture of the patella. Additionally, injury to the extensor mechanism may come from a partial or full disruption of the patellar or quadriceps tendon. A professional baseball player suffered an injury to his knee after he collided with an outfield wall. Acute swelling in the suprapatellar soft tissues concealed a palpable defect, which initially was suspected to be an injury to the quadriceps tendon. Magnetic resonance imaging of the knee revealed an intact extensor mechanism; moreover, a fracture of the subcutaneous fat anterior to the quadriceps tendon was evident and diagnosed as a fat fracture.

Fat fracture is a rare diagnosis, and to the best of our knowledge, this is the first reported diagnosis in a professional athlete. Conservative management including, but not limited to, range of motion exercises, hydrotherapy, and iontophoresis effectively treated the athlete’s injury.

Blunt trauma to the anterior knee can result in a contusion or fracture of the patella, subluxation of the patella, and injury to the quadriceps or patellar tendon. Typically, a contusion or non-displaced fracture of the patella clinically presents with a direct anterior effusion and point tenderness. A displaced fracture or tendon deficit typically has an extensor lag or weakness in extension. Fat fracture or traumatic lipomata has been previously described in 1 case of anterior knee pain after blunt injury.¹

In this article, we present the case of a 32-year-old professional baseball player who suffered a blunt injury to his left knee after collision with the outfield wall and experienced both anterior and medial knee pain. The patient provided written informed consent for print and electronic publication of this case report.

CASE

A 32-year-old outfielder for a professional baseball team was attempting a catch in the outfield when his left knee collided with the padded outfield wall in a semiflexed position. The player was able to walk off the field in the middle of the inning; however, he then experienced increasing pain and was unable to return to play. He had no prior history of significant knee pain or injury. He complained only of pain, with no instability or sensation of catching or locking.

Continue to: Physical examination of the patient...

Mild coronal laxity of the patella was noted compared with that of the contralateral knee. Hip range of motion (ROM) was intact, but knee ROM was limited to 110° of flexion, with the complaint of anterior tightness at this position. He was able to fully extend his knee without symptoms. The knee was stable to varus and valgus stress at both 0° and 30° of flexion. Lachman and anterior and posterior drawer tests were negative and symmetric to the contralateral knee. The McMurray test for meniscal pathology also was negative. Radiographs of the left knee were completed and were negative for fracture.

OUTCOMES

The initial clinical diagnosis was a patellar contusion and sprain of the medial retinaculum, and the athlete was treated with multiple modalities available in the athletic training room. Rehabilitation included activity modifications, passive and active ROM activities, quadriceps isometric exercises, and neuromuscular control activities. Adjunctive modalities included cryotherapy, hydrotherapy, topical hematoma cream, and iontophoresis.² This aggressive treatment was continued for 3 days with decreased but persistent pain with running drills and limited knee flexion. Repeat clinical examination revealed a decreased swelling, but there was evidence of a clinically palpable defect anteriorly proximal to the patella. Although the patient could perform a straight leg raise, a partial injury to the quadriceps became plausible. Magnetic resonance imaging (MRI) of the left knee was performed, owing to the persistent pain and limited flexion despite aggressive conservative management, as well as the palpable soft-tissue defect.

MRI was performed using a 3T (Tesla) system (GE Healthcare) with a GE Healthcare Precision 8-channel knee coil. Routine knee protocol imaging was performed to include the distal quadriceps tendon due to clinical concern for a quadriceps tear. Sagittal proton density and proton-density fat-saturated (PD FS), coronal T1 and PD FS, and axial T1 and PD FS sequences were acquired.

An acutely marginated, 1.5 cm × 3 cm, longitudinal and transverse fluid defect “crevasse” was identified at the midline in the prepatellar subcutaneous fat overlying the distal quadriceps tendon and corresponded to a clinically palpable abnormality (Figures 1, 2). 

Continue to: These findings explained...

DISCUSSION

A fat fracture was first described in 1972 in 12 cases of buttock fat fractures after blunt trauma.³ The authors explained that fat lobules are typically arranged in layers and supported by horizontal and vertical fibrous septa. Typical loads flatten the lobules and disperse the forces throughout the layer. However, abnormal loads to a local area disrupt the fat lobules and shear the septa, resulting in decreased integrity of the interface between the epidermis and the fascia.

However, the extremities typically have less adipose tissue than in the buttocks, and the anterior knee is prone to blunt trauma. A previous description of a fat fracture in the knee noted a palpable defect in the quadriceps tendon and an inability to perform a straight leg raise. Our case initially presented with swelling, which concealed any soft-tissue defect. Furthermore, a straight leg raise was always intact despite the fat fracture defect surfacing after anterior swelling subsided. However, the disparity in these 2 cases highlights the spectrum of injury that is possible, as well as the difficulty in diagnosing a fat fracture. The previous report used ultrasound to confirm the diagnosis and assess the integrity of adjacent musculotendinous structures. An ultrasound may be readily available in athletic training rooms.¹ Of note, to the best of our knowledge, this is the first case in the literature to report a fat fracture in a professional athlete and in baseball players. Furthermore, this case report describes an athlete who presented with anterior and medial knee pain. The edema from the fat fracture dispersed into the medial prepatellar bursa, which could be confused with edema from an injury to the medial-sided soft tissues.

Although these injuries do not require operative management, conservative measures may not be as effective as those in a patellar contusion or ligamentous sprain, and prolonged treatment may be necessary. Additionally, healthcare providers should be aware of this possible source of injury and counsel on an appropriate recovery time. Ideally, further recognition of such injuries can facilitate improved management and a faster return to activity.

ABSTRACT

Blunt trauma to the anterior knee typically results in a contusion or fracture of the patella. Additionally, injury to the extensor mechanism may come from a partial or full disruption of the patellar or quadriceps tendon. A professional baseball player suffered an injury to his knee after he collided with an outfield wall. Acute swelling in the suprapatellar soft tissues concealed a palpable defect, which initially was suspected to be an injury to the quadriceps tendon. Magnetic resonance imaging of the knee revealed an intact extensor mechanism; moreover, a fracture of the subcutaneous fat anterior to the quadriceps tendon was evident and diagnosed as a fat fracture.

Fat fracture is a rare diagnosis, and to the best of our knowledge, this is the first reported diagnosis in a professional athlete. Conservative management including, but not limited to, range of motion exercises, hydrotherapy, and iontophoresis effectively treated the athlete’s injury.

Blunt trauma to the anterior knee can result in a contusion or fracture of the patella, subluxation of the patella, and injury to the quadriceps or patellar tendon. Typically, a contusion or non-displaced fracture of the patella clinically presents with a direct anterior effusion and point tenderness. A displaced fracture or tendon deficit typically has an extensor lag or weakness in extension. Fat fracture or traumatic lipomata has been previously described in 1 case of anterior knee pain after blunt injury.¹

In this article, we present the case of a 32-year-old professional baseball player who suffered a blunt injury to his left knee after collision with the outfield wall and experienced both anterior and medial knee pain. The patient provided written informed consent for print and electronic publication of this case report.

CASE

A 32-year-old outfielder for a professional baseball team was attempting a catch in the outfield when his left knee collided with the padded outfield wall in a semiflexed position. The player was able to walk off the field in the middle of the inning; however, he then experienced increasing pain and was unable to return to play. He had no prior history of significant knee pain or injury. He complained only of pain, with no instability or sensation of catching or locking.

Continue to: Physical examination of the patient...

Mild coronal laxity of the patella was noted compared with that of the contralateral knee. Hip range of motion (ROM) was intact, but knee ROM was limited to 110° of flexion, with the complaint of anterior tightness at this position. He was able to fully extend his knee without symptoms. The knee was stable to varus and valgus stress at both 0° and 30° of flexion. Lachman and anterior and posterior drawer tests were negative and symmetric to the contralateral knee. The McMurray test for meniscal pathology also was negative. Radiographs of the left knee were completed and were negative for fracture.

OUTCOMES

The initial clinical diagnosis was a patellar contusion and sprain of the medial retinaculum, and the athlete was treated with multiple modalities available in the athletic training room. Rehabilitation included activity modifications, passive and active ROM activities, quadriceps isometric exercises, and neuromuscular control activities. Adjunctive modalities included cryotherapy, hydrotherapy, topical hematoma cream, and iontophoresis.² This aggressive treatment was continued for 3 days with decreased but persistent pain with running drills and limited knee flexion. Repeat clinical examination revealed a decreased swelling, but there was evidence of a clinically palpable defect anteriorly proximal to the patella. Although the patient could perform a straight leg raise, a partial injury to the quadriceps became plausible. Magnetic resonance imaging (MRI) of the left knee was performed, owing to the persistent pain and limited flexion despite aggressive conservative management, as well as the palpable soft-tissue defect.

MRI was performed using a 3T (Tesla) system (GE Healthcare) with a GE Healthcare Precision 8-channel knee coil. Routine knee protocol imaging was performed to include the distal quadriceps tendon due to clinical concern for a quadriceps tear. Sagittal proton density and proton-density fat-saturated (PD FS), coronal T1 and PD FS, and axial T1 and PD FS sequences were acquired.

An acutely marginated, 1.5 cm × 3 cm, longitudinal and transverse fluid defect “crevasse” was identified at the midline in the prepatellar subcutaneous fat overlying the distal quadriceps tendon and corresponded to a clinically palpable abnormality (Figures 1, 2). 

Continue to: These findings explained...

DISCUSSION

A fat fracture was first described in 1972 in 12 cases of buttock fat fractures after blunt trauma.³ The authors explained that fat lobules are typically arranged in layers and supported by horizontal and vertical fibrous septa. Typical loads flatten the lobules and disperse the forces throughout the layer. However, abnormal loads to a local area disrupt the fat lobules and shear the septa, resulting in decreased integrity of the interface between the epidermis and the fascia.

However, the extremities typically have less adipose tissue than in the buttocks, and the anterior knee is prone to blunt trauma. A previous description of a fat fracture in the knee noted a palpable defect in the quadriceps tendon and an inability to perform a straight leg raise. Our case initially presented with swelling, which concealed any soft-tissue defect. Furthermore, a straight leg raise was always intact despite the fat fracture defect surfacing after anterior swelling subsided. However, the disparity in these 2 cases highlights the spectrum of injury that is possible, as well as the difficulty in diagnosing a fat fracture. The previous report used ultrasound to confirm the diagnosis and assess the integrity of adjacent musculotendinous structures. An ultrasound may be readily available in athletic training rooms.¹ Of note, to the best of our knowledge, this is the first case in the literature to report a fat fracture in a professional athlete and in baseball players. Furthermore, this case report describes an athlete who presented with anterior and medial knee pain. The edema from the fat fracture dispersed into the medial prepatellar bursa, which could be confused with edema from an injury to the medial-sided soft tissues.

Although these injuries do not require operative management, conservative measures may not be as effective as those in a patellar contusion or ligamentous sprain, and prolonged treatment may be necessary. Additionally, healthcare providers should be aware of this possible source of injury and counsel on an appropriate recovery time. Ideally, further recognition of such injuries can facilitate improved management and a faster return to activity.

ABSTRACT

Blunt trauma to the anterior knee typically results in a contusion or fracture of the patella. Additionally, injury to the extensor mechanism may come from a partial or full disruption of the patellar or quadriceps tendon. A professional baseball player suffered an injury to his knee after he collided with an outfield wall. Acute swelling in the suprapatellar soft tissues concealed a palpable defect, which initially was suspected to be an injury to the quadriceps tendon. Magnetic resonance imaging of the knee revealed an intact extensor mechanism; moreover, a fracture of the subcutaneous fat anterior to the quadriceps tendon was evident and diagnosed as a fat fracture.

Fat fracture is a rare diagnosis, and to the best of our knowledge, this is the first reported diagnosis in a professional athlete. Conservative management including, but not limited to, range of motion exercises, hydrotherapy, and iontophoresis effectively treated the athlete’s injury.

Blunt trauma to the anterior knee can result in a contusion or fracture of the patella, subluxation of the patella, and injury to the quadriceps or patellar tendon. Typically, a contusion or non-displaced fracture of the patella clinically presents with a direct anterior effusion and point tenderness. A displaced fracture or tendon deficit typically has an extensor lag or weakness in extension. Fat fracture or traumatic lipomata has been previously described in 1 case of anterior knee pain after blunt injury.¹

In this article, we present the case of a 32-year-old professional baseball player who suffered a blunt injury to his left knee after collision with the outfield wall and experienced both anterior and medial knee pain. The patient provided written informed consent for print and electronic publication of this case report.

CASE

A 32-year-old outfielder for a professional baseball team was attempting a catch in the outfield when his left knee collided with the padded outfield wall in a semiflexed position. The player was able to walk off the field in the middle of the inning; however, he then experienced increasing pain and was unable to return to play. He had no prior history of significant knee pain or injury. He complained only of pain, with no instability or sensation of catching or locking.

Continue to: Physical examination of the patient...

Mild coronal laxity of the patella was noted compared with that of the contralateral knee. Hip range of motion (ROM) was intact, but knee ROM was limited to 110° of flexion, with the complaint of anterior tightness at this position. He was able to fully extend his knee without symptoms. The knee was stable to varus and valgus stress at both 0° and 30° of flexion. Lachman and anterior and posterior drawer tests were negative and symmetric to the contralateral knee. The McMurray test for meniscal pathology also was negative. Radiographs of the left knee were completed and were negative for fracture.

OUTCOMES

The initial clinical diagnosis was a patellar contusion and sprain of the medial retinaculum, and the athlete was treated with multiple modalities available in the athletic training room. Rehabilitation included activity modifications, passive and active ROM activities, quadriceps isometric exercises, and neuromuscular control activities. Adjunctive modalities included cryotherapy, hydrotherapy, topical hematoma cream, and iontophoresis.² This aggressive treatment was continued for 3 days with decreased but persistent pain with running drills and limited knee flexion. Repeat clinical examination revealed a decreased swelling, but there was evidence of a clinically palpable defect anteriorly proximal to the patella. Although the patient could perform a straight leg raise, a partial injury to the quadriceps became plausible. Magnetic resonance imaging (MRI) of the left knee was performed, owing to the persistent pain and limited flexion despite aggressive conservative management, as well as the palpable soft-tissue defect.

MRI was performed using a 3T (Tesla) system (GE Healthcare) with a GE Healthcare Precision 8-channel knee coil. Routine knee protocol imaging was performed to include the distal quadriceps tendon due to clinical concern for a quadriceps tear. Sagittal proton density and proton-density fat-saturated (PD FS), coronal T1 and PD FS, and axial T1 and PD FS sequences were acquired.

An acutely marginated, 1.5 cm × 3 cm, longitudinal and transverse fluid defect “crevasse” was identified at the midline in the prepatellar subcutaneous fat overlying the distal quadriceps tendon and corresponded to a clinically palpable abnormality (Figures 1, 2). 

Continue to: These findings explained...

DISCUSSION

A fat fracture was first described in 1972 in 12 cases of buttock fat fractures after blunt trauma.³ The authors explained that fat lobules are typically arranged in layers and supported by horizontal and vertical fibrous septa. Typical loads flatten the lobules and disperse the forces throughout the layer. However, abnormal loads to a local area disrupt the fat lobules and shear the septa, resulting in decreased integrity of the interface between the epidermis and the fascia.

However, the extremities typically have less adipose tissue than in the buttocks, and the anterior knee is prone to blunt trauma. A previous description of a fat fracture in the knee noted a palpable defect in the quadriceps tendon and an inability to perform a straight leg raise. Our case initially presented with swelling, which concealed any soft-tissue defect. Furthermore, a straight leg raise was always intact despite the fat fracture defect surfacing after anterior swelling subsided. However, the disparity in these 2 cases highlights the spectrum of injury that is possible, as well as the difficulty in diagnosing a fat fracture. The previous report used ultrasound to confirm the diagnosis and assess the integrity of adjacent musculotendinous structures. An ultrasound may be readily available in athletic training rooms.¹ Of note, to the best of our knowledge, this is the first case in the literature to report a fat fracture in a professional athlete and in baseball players. Furthermore, this case report describes an athlete who presented with anterior and medial knee pain. The edema from the fat fracture dispersed into the medial prepatellar bursa, which could be confused with edema from an injury to the medial-sided soft tissues.

Although these injuries do not require operative management, conservative measures may not be as effective as those in a patellar contusion or ligamentous sprain, and prolonged treatment may be necessary. Additionally, healthcare providers should be aware of this possible source of injury and counsel on an appropriate recovery time. Ideally, further recognition of such injuries can facilitate improved management and a faster return to activity.

Take-Home Points

• Stress fractures should always be considered when dealing with overuse injuries.
• Radial shaft stress fractures in overhead throwing athletes are rare.
• Stress fractures can occur anywhere increased muscular forces exceed the bone’s ability to remodel.
• Proper imaging is necessary to make the diagnosis of a stress fracture.
• Nonoperative management of radial shaft stress fractures is an effective treatment.

In athletes, the incidence of stress fractures has been reported to be 1.4% to 4.4%.¹ Stress fractures of the upper extremity are less common and not as well described as lower extremity stress fractures. Although data is lacking, stress fractures involving the upper extremity appear to account for <6% of all stress fractures.² Stress fractures of the upper extremity, though rare, are being recognized more often in overhead athletes.^3-6 In baseball pitchers, stress fractures most commonly occur in the olecranon but have also been found in the ribs, clavicle, humerus, and ulnar shaft.^2,4,7-10 Stress fractures of the radius are a rare cause of forearm pain in athletes, and there are only a few case reports involving overhead athletes.^4,11-15 To our knowledge, a stress fracture of the radial shaft has not been reported in a throwing athlete. Currently, there are no reports on stress fractures of the proximal radial shaft.^16-18

In this article, we report the case of a radial shaft stress fracture that was causing forearm pain in a Major League Baseball (MLB) pitcher. We also discuss the etiology, diagnosis, and management of stress fractures of the upper extremity of overhead throwing athletes. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 28-year-old right-hand-dominant MLB pitcher presented to the clinic with a 4-week history of right dorsal forearm pain that was refractory to a period of rest and physical therapy modalities. The pain radiated to the wrist and along the dorsal forearm. The pain started after the man attempted to develop a new pitch that required a significant amount of supination. The pain prevented him from pitching competitively. Indomethacin, diclofenac sodium topical gel, and methylprednisolone (Medrol Dosepak) reduced his symptoms only slightly.

Physical examination of the right elbow showed mild range of motion deficits; about 5° of extension and 5° of flexion were lacking. The patient had full pronation and supination. Palpation of the dorsal aspect of the forearm revealed marked tenderness in the area of the proximal radius. There was no tenderness over the posterior olecranon or the ulnar collateral ligament, and a moving valgus stress test was negative. No pain was elicited by resisted extension of the wrist or fingers. Motor innervation from the posterior interosseous nerve, anterior interosseous nerve, and ulnar nerve was intact with 5/5 strength, and there were no sensory deficits in the distribution of the radial, median, or ulnar nerves.

Discussion

Stress fractures account for 0.7% to 20% of sports medicine clinic injuries; <10% of all stress fractures involve the rib or upper extremity.^4,6 When the intensity or frequency of physical activity is increased, as with overuse, bone resorption surpasses bone production, locally weakening the bone and making it prone to mechanical failure. Failure is thought to be induced by a combination of contractile muscular forces across damaged bone and increased mechanical loading caused by fatigue of supporting structures.^5,6,19 These forces may have contributed to our baseball pitcher’s development of a stress fracture near the insertion of the supinator muscle in his throwing arm.

Given the insidious nature of stress fractures, the evaluating physician must have a high index of suspicion. Early recognition of a stress fracture is important in preventing further injury and allowing for early intervention, which is associated with faster healing.^6,20 The clinical history often involves a change in training regimen within the weeks before pain onset. Furthermore, understanding the type of pitches used and the mechanics of each pitch can help with diagnosis. Often, pain increases as the inciting activity continues, and relief comes with rest. In an upper extremity examination, it is important to recall the usual stress fracture locations in throwers—the ribs, clavicle, humerus, ulnar shaft, and most often the olecranon—though the patient’s history often narrows the anatomical region of suspicion.^2,4,7-10 Examination begins with inspection of the skin and soft tissues. Range of motion and strength testing results likely are normal throughout the upper extremity.³ Palpation over the suspected injury location often elicits pain and indicates further imaging is needed.⁶ The tuning fork test or the 3-point fulcrum test may elicit symptoms in occult fractures.3 Completing the assessment is a thorough neurovascular examination.

Insidious forearm pain requires a broad differential, including flexor-pronator mass or distal biceps injury, chronic exertional compartment syndrome, radial tunnel syndrome, intersection syndrome, pronator teres syndrome, anterior interosseous syndrome, thoracic outlet syndrome, musculocutaneous nerve compression, deep vein thrombosis of ulnar vein, and periostitis. Stress fractures distal to the elbow more commonly occur in weight-bearing athletes, though as this case shows it is important to consider stress fractures of the radius and ulna when evaluating forearm pain in a throwing athlete.²¹

The first imaging examination for a suspected stress fracture is a radiograph, which can be normal in up to 90% of patients, as it initially was in our athlete’s case.²² Often, radiographic evidence takes 2 to 12 weeks to appear.⁵ Even then, radiographs may be positive in only 50% of cases.¹⁹ CT, often regarded as insensitive during the early stages, is useful in visualizing fracture lines in a suspicious location.^19,22 Radionuclide uptake scanning is highly sensitive during the early stages of stress injury but is nonspecific and may indicate neoplasm or infection; in addition, up to 46% of abnormal foci are asymptomatic.¹⁹ MRI has sensitivity comparable to that of radionuclide scanning but also many advantages, including lack of ionizing radiation, improved spatial resolution, and ability to image bone and soft tissue simultaneously.¹⁹ In our patient’s case, the unusual stress fracture location potentially could have hindered identification of the cause of injury. The lesion was just distal to the field of view of a normal elbow MRI and was not detected until a dedicated forearm MRI was examined. Both MRI and CT helped in identifying the stress fracture, and CT was used to follow interval healing.

In baseball players, upper extremity stress fractures are often nonoperatively treated with throwing cessation for 4 to 6 weeks followed by participation in a structured rehabilitation program.4,5 The throwing program that we suggest, and that was used in this case, has 21 stages of progression in duration, distance, and velocity of throwing. The athlete advances from each stage on the basis of symptoms.²³ Other issues that may be addressed are vitamin D and calcium status and any flawed throwing mechanics that may have predisposed the athlete to injury. Such mechanics are gradually corrected.

The literature suggests that appropriate nonoperative management of stress fractures allows for return to sport in 8 to 10 weeks. It is important to note that most of the literature on stress fractures involves the lower extremity, and that treatment and time to return to play are therefore better described for such fractures.6 More study and evaluation of upper extremity stress fractures are needed to make return-to-sport predictions more reliable and successful treatment modalities more unified for this patient population. Last, it is imperative that clinical examination and symptoms be correlated with serial imaging when deciding on return to play. Our patient took 12 weeks to return to high-level sport. He progressed pain-free through the throwing program and showed radiographic evidence of healing on follow-up CT.

Conclusion

Radial shaft stress fractures are rare in throwing athletes. However, with a thorough history, a physical examination, and appropriate imaging, the correct diagnosis can be made early on, and proper treatment can be started to facilitate return to sport. To our knowledge, this is the first report of a stress fracture in the radial shaft of a MLB pitcher. Although the radial shaft is an uncommon location for stress fractures, we should keep in mind that they can occur wherever increased muscular forces exceed the ability of native bone to remodel. After diagnosis, the fracture usually heals with nonoperative treatment, and healing is confirmed with follow-up imaging, as was done in our patient’s case. Improved prediction of time to return to play for upper extremity fractures, such as the radial stress fracture described in this article, requires more study.