Orthopedics

A common entity, osteoarthritis (OA) at the base of the thumb is largely caused by the unique anatomy and biomechanics of the thumb carpometacarpal (CMC) joint.¹ Radiographically evident CMC degeneration occurs in 40% of women and 25% of men over age 75 years, making the thumb CMC joint the most common site of surgical reconstruction for upper extremity OA.^2,3

Over the past 40 years, numerous surgical techniques for managing thumb CMC-OA have been described. These include volar ligament reconstruction, first metacarpal osteotomy, CMC arthrodesis, CMC joint replacement, and trapeziectomy. Trapeziectomy can be performed in isolation or in combination with tendon interposition, ligament reconstruction, or ligament reconstruction and tendon interposition (LRTI).^4-20 The authors of a recent systematic review concluded there is no evidence that any one surgical procedure for CMC-OA is superior to another in terms of pain, function, satisfaction, range of motion, or strength.⁴ Nevertheless, a recent survey found that 719 (62%) of 1156 US hand surgeons used LRTI as the treatment of choice for advanced CMC-OA.²¹

Our detailed literature search yielded no other database studies characterizing current trends in the practice patterns of US orthopedic surgeons who perform interposition arthroplasty for CMC arthritis. Analysis of these trends is important not only to patients but also to the broader orthopedic and health care community.²²

We conducted a study to investigate current trends in CMC interposition arthroplasty across time, sex, age, and region of the United States; per-patient charges and reimbursements; and the association between this procedure and concomitantly performed carpal tunnel syndrome (CTS) and carpal tunnel release (CTR). In addition, we compared incidence of CMC interposition arthroplasty with that of CMC arthrodesis.

Patients and Methods

All data were derived from the PearlDiver Patient Records Database (PearlDiver Technologies), a publicly available database of patients. The database stores procedure volumes, demographics, and average charge information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the present study were drawn from the Medicare database within the PearlDiver records, which has a total of 179,094,296 patient records covering the period 2005–2011. This study did not require institutional review board approval, as it used existing, publicly available data without identifiers linked to subjects.

PearlDiver Technologies granted us database access for academic research. The database was stored on a password-protected server maintained by PearlDiver. ICD-9 and CPT codes can be searched in isolation or in combination. Search results yield number of patients with a searched code (or combination of codes) in each year, age group, or region of the United States, as well as mean charge and mean reimbursement for the code or combination of codes.

We used CPT code 25447 (arthroplasty, interposition, intercarpal, or CMC joints) to search the database for patients who underwent thumb CMC interposition arthroplasty. Although this code does not specify thumb, we are unaware of any procedure (other than thumb CMC interposition arthroplasty) typically given this code. Our search yielded procedure volumes, sex distribution, age distribution, region volumes, and mean per-patient charges and reimbursements for each CPT code. We then searched the resulting cohort for CTS (ICD-9 code 354.0), endoscopic CTR (CPT code 29848), and open CTR (CPT code 64721) to find CTR performed concomitantly with CMC interposition arthroplasty. Last, patients were tracked in the database past their surgery date to evaluate for postoperative physical or occupational therapy evaluations within 6 months (using CPT codes appearing in at least 1% of the cohort: 97001, 97003, 97004, 97110, 97112, 97124, 97140, 97150, 97350, 97535) and postoperative thumb, hand, or wrist radiographs within 6 months (using CPT codes appearing in at least 1% of the cohort: 73140, 73130, 73110). To ensure adequacy of 6-month postoperative data, we included in this portion of the study only those patients with surgery dates between 2005 and 2010.

For comparative purposes, we also searched the database for patients who underwent thumb CMC arthrodesis within the same period—using CPT codes 26841 and 26842 (arthrodesis CMC joint thumb, with or without internal fixation; with or without autograft) and CPT code 26820 (fusion in opposition, thumb, with autogenous graft).

Overall procedure volume data are reported as number of patients with the given CPT code in the database output in a given year. Age-group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who underwent the CPT code of interest that year. Mean charges and reimbursements are reported as results by the database for the code of interest (CPT 25447). Data for the region analysis are presented as an incidence, as there is an uneven distribution of patient volumes among regions. This incidence is calculated as number of patients in a particular region and year normalized to total number of patients in the database for that particular region or year. Regions are defined as Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MS, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-squared linear-by-linear association analysis was used to determine statistical significance with regard to trends over time in procedure volumes, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

Results

In the database, we identified 41,171 unique patients who underwent CMC interposition arthroplasty between 2005 and 2011. Over the 7-year study period, number of patients who had CMC interposition arthroplasty increased 46.2%, from 4761 in 2005 to 6960 in 2011 (P < .0001) (Table 1, Figure 1). Throughout this period, females underwent CMC interposition arthroplasty more frequently than males at all time points (P < .0001). Overall ratio of female to male patients, however, changed significantly. In 2005, 18.1% of all CMC interposition arthroplasties were performed on male patients; this increased to 23.9% of all procedures by 2011 (P < .0001) (Figure 2). Table 1 presents an age-group analysis. There were no significant differences in relative percentage of patients in any given age group who underwent CMC interposition arthroplasty over the study period.

Analysis of overall procedure incidence by region revealed significant increases in all regions (P < .0001), ranging from 18.5% (West) to 54.5% (Northeast) (Figure 3). At all time points, the incidence of CMC interposition arthroplasty was significantly lower in the Northeast than in any other region and compared with the overall average.

Between 2005 and 2011, there were significant increases in both per-patient charges and reimbursements for CMC interposition arthroplasty (Figure 4). Mean per-patient charge increased from $2676 in 2005 to $4181 in 2011 (P < .0001), and mean per-patient reimbursement increased from $1445 in 2005 to $2061 in 2011 (P < .0001). The discrepancy between charge and reimbursement increased throughout the study period: Reimbursement in 2005 was 54.0% of the charge; this decreased to 49.3% by 2011 but was not statistically significant (P = .08).

Overall, 40.9% of patients who underwent CMC interposition arthroplasty also had a CTS diagnosis. Between 15.5% and 17.3% of these patients had concomitant open or endoscopic CTR at time of CMC interposition arthroplasty (Table 2). Percentage of patients who underwent concomitant CTR did not change significantly from 2005 to 2011 (P = .139). Use of postoperative occupational and/or physical therapy increased significantly over the study period, from 33.5% of patients in 2005 to 50.7% of patients in 2010 (P < .0001). Use of postoperative thumb, hand, and/or wrist radiography also increased throughout the study period, from 7.4% of patients in 2005 to 18.7% of patients in 2010 (P < .0001).

We identified 1916 unique patients who underwent thumb CMC arthrodesis between 2005 and 2011. Over the 7-year study period, there was a 19.1% decrease in number of patients who underwent CMC arthrodesis, from 309 in 2005 to 250 in 2011 (P < .0001) (Figure 5). Significantly fewer patients had CMC arthrodesis compared with CMC interposition arthroplasty at all time points, ranging from 6.5% (thumb CMC arthrodesis:CMC interposition arthroplasty) in 2005 to 3.6% in 2011 (P < .0001).

Discussion

Our results demonstrated a significant increase in use of thumb CMC interposition arthroplasty in a US Medicare population, with an increase of more than 46% from 2005 to 2011. This finding supports the findings of a recent cross-sectional survey-based study in which 719 (62%) of 1156 surveyed US hand surgeons reported performing trapeziectomy with LRTI for advanced thumb CMC-OA.²¹ A prior study had similar findings, with 692 (68%) of 1024 American Society for Surgery of the Hand (ASSH) members performing LRTI and 766 (75%) of 1024 performing some type of CMC interposition with trapeziectomy for advanced CMC-OA.²³ This preference for CMC interposition arthroplasty prevails despite the fact that numerous studies have shown no superiority of any surgical procedure to another for CMC-OA in terms of pain, function, satisfaction, range of motion, and strength.^{7,15,18,19,24-34} Our data demonstrated that, not only does CMC interposition arthroplasty remain the most frequently used procedure for thumb CMC-OA, the incidence of CMC interposition arthroplasty continues to increase yearly.

The incidence of thumb CMC-OA is higher in women than in men, with more joint laxity a known contributor and subtle sex differences in trapezium geometry and congruence postulated as additional factors.^3,35,36 This trend was confirmed in the present study, as females underwent significantly more CMC interposition arthroplasties at all time points. It is interesting that the overall ratio of female to male patients changed significantly over the study period, with the percentage of patients who were male increasing from 18.1% in 2005 to 23.9% in 2011. No previous studies have captured such a large cross section of the population to establish this trend. Although this trend is not necessarily intuitive, potential theories include increased acceptance of CMC interposition arthroplasty as a surgical option for male patients, and potentially a larger number of male patients seeking medical care for thumb CMC-OA in recent years.

Increases in procedure incidence were noted in all regions of the United States, but the largest percentage increase occurred in the Northeast. Despite this increase, the Northeast also had significantly lower CMC interposition arthroplasty incidence compared with all other regions and with the average procedure incidence throughout the study period—demonstrating some regional bias as to treatment of thumb CMC-OA. Unfortunately, because of database limitations and lack of specific CPT codes for other treatment options for thumb CMC-OA, we cannot ascertain if other types of surgery are more frequently used in the Northeast.

CTS and thumb CMC-OA often coexist.³⁷ The estimated incidence of concomitant CTS in patients with CMC-OA is between 4% and 43%, but the rate of concomitant CTR and CMC interposition arthroplasty was not previously characterized in the literature.^38,39 Results of the present study supported these findings; 41% of patients who underwent CMC interposition arthroplasty in our study also had a CTS diagnosis, compared with 43% in the 246-patient study by Florack and colleagues.³⁸ We also found that 16% to 17% of patients who underwent CMC interposition arthroplasty underwent concomitant CTR; this rate remained consistent throughout the study period.

Our study demonstrated that, compared with CMC interposition arthroplasties, significantly fewer thumb CMC arthrodesis procedures were performed in the same Medicare population during the same period. Furthermore, the number of thumb CMC arthrodesis procedures declined yearly, with an overall decrease of 19% from 2005 to 2011. In a recent single-blinded, randomized trial, Vermeulen and colleagues⁴⁰ compared thumb CMC arthrodesis and trapeziectomy with LRTI. They found superior patient satisfaction and significantly lower complication rates in women who underwent LRTI versus arthrodesis. The study was terminated prematurely because of these complications and thus was underpowered to determine differences in specific outcome measures. Previous studies comparing arthrodesis and interposition arthroplasties reported inconsistent outcomes. Hart and colleagues⁴¹ found no significant differences in pain or function between CMC arthrodesis and LRTI at a mean 7-year follow-up in a level II randomized controlled trial. Hartigan and colleagues¹⁵ reached similar conclusions in their retrospective comparison of the procedures. Without clear evidence supporting arthrodesis over interposition arthroplasty, the majority of surgeons favor interposition arthroplasty for thumb CMC-OA. Among Medicare patients, use of thumb CMC arthrodesis continues to fall.

This national database study had several limitations, which are common to all studies using the PearlDiver database^22,42-47:

1. The power of the analysis depended on the quality of available data. Potential sources of error included accuracy of billing codes, and miscoding or noncoding by physicians.⁴⁶

2. Although we used this database to try to accurately represent a large population of interest, we cannot guarantee the database represented a true cross section of the United States.

3. For the Medicare population, the PearlDiver database indexes data only in 7-year increments. Although the study period was long enough to detect significant trends, some data may not be accurately captured over a 7-year period.

4. Patients were not randomized to a treatment group.

5. The PearlDiver database does not include any clinical outcome data. Therefore, we cannot comment on the efficacy of the reported evaluations and interventions.

6. There is no specific CPT code for thumb CMC interposition arthroplasty. However, we are unaware of a CMC interposition arthroplasty performed for any area besides the thumb. Theoretically, the study population can include a negligible percentage of patients who had interposition arthroplasty of a CMC joint other than the thumb.

7. The database cannot be searched for use of thumb CMC-OA surgical techniques other than CMC interposition arthroplasty or arthrodesis, as isolated trapeziectomy, volar ligament reconstruction, implant arthroplasty, and metacarpal osteotomy lack specific CPT codes.

Conclusion

Thumb CMC-OA is a common entity among Medicare patients. There are numerous surgical options for cases that have failed conservative treatment. Despite the lack of evidence that thumb CMC interposition arthroplasty is superior to other surgical options, the number of patients who had this procedure increased 46% during the 2005–2011 study period. Although the majority of patients who undergo CMC interposition arthroplasty are female, the percentage of male patients has increased significantly. More than 40% of patients who have CMC interposition arthroplasty are also diagnosed with CTS, and 16% to 17% of patients who have CMC interposition arthroplasty will have a concomitant CTR. CMC arthrodesis is used in significantly fewer patients of Medicare age, and its use has been declining.

A common entity, osteoarthritis (OA) at the base of the thumb is largely caused by the unique anatomy and biomechanics of the thumb carpometacarpal (CMC) joint.¹ Radiographically evident CMC degeneration occurs in 40% of women and 25% of men over age 75 years, making the thumb CMC joint the most common site of surgical reconstruction for upper extremity OA.^2,3

Over the past 40 years, numerous surgical techniques for managing thumb CMC-OA have been described. These include volar ligament reconstruction, first metacarpal osteotomy, CMC arthrodesis, CMC joint replacement, and trapeziectomy. Trapeziectomy can be performed in isolation or in combination with tendon interposition, ligament reconstruction, or ligament reconstruction and tendon interposition (LRTI).^4-20 The authors of a recent systematic review concluded there is no evidence that any one surgical procedure for CMC-OA is superior to another in terms of pain, function, satisfaction, range of motion, or strength.⁴ Nevertheless, a recent survey found that 719 (62%) of 1156 US hand surgeons used LRTI as the treatment of choice for advanced CMC-OA.²¹

Our detailed literature search yielded no other database studies characterizing current trends in the practice patterns of US orthopedic surgeons who perform interposition arthroplasty for CMC arthritis. Analysis of these trends is important not only to patients but also to the broader orthopedic and health care community.²²

We conducted a study to investigate current trends in CMC interposition arthroplasty across time, sex, age, and region of the United States; per-patient charges and reimbursements; and the association between this procedure and concomitantly performed carpal tunnel syndrome (CTS) and carpal tunnel release (CTR). In addition, we compared incidence of CMC interposition arthroplasty with that of CMC arthrodesis.

Patients and Methods

All data were derived from the PearlDiver Patient Records Database (PearlDiver Technologies), a publicly available database of patients. The database stores procedure volumes, demographics, and average charge information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the present study were drawn from the Medicare database within the PearlDiver records, which has a total of 179,094,296 patient records covering the period 2005–2011. This study did not require institutional review board approval, as it used existing, publicly available data without identifiers linked to subjects.

PearlDiver Technologies granted us database access for academic research. The database was stored on a password-protected server maintained by PearlDiver. ICD-9 and CPT codes can be searched in isolation or in combination. Search results yield number of patients with a searched code (or combination of codes) in each year, age group, or region of the United States, as well as mean charge and mean reimbursement for the code or combination of codes.

We used CPT code 25447 (arthroplasty, interposition, intercarpal, or CMC joints) to search the database for patients who underwent thumb CMC interposition arthroplasty. Although this code does not specify thumb, we are unaware of any procedure (other than thumb CMC interposition arthroplasty) typically given this code. Our search yielded procedure volumes, sex distribution, age distribution, region volumes, and mean per-patient charges and reimbursements for each CPT code. We then searched the resulting cohort for CTS (ICD-9 code 354.0), endoscopic CTR (CPT code 29848), and open CTR (CPT code 64721) to find CTR performed concomitantly with CMC interposition arthroplasty. Last, patients were tracked in the database past their surgery date to evaluate for postoperative physical or occupational therapy evaluations within 6 months (using CPT codes appearing in at least 1% of the cohort: 97001, 97003, 97004, 97110, 97112, 97124, 97140, 97150, 97350, 97535) and postoperative thumb, hand, or wrist radiographs within 6 months (using CPT codes appearing in at least 1% of the cohort: 73140, 73130, 73110). To ensure adequacy of 6-month postoperative data, we included in this portion of the study only those patients with surgery dates between 2005 and 2010.

For comparative purposes, we also searched the database for patients who underwent thumb CMC arthrodesis within the same period—using CPT codes 26841 and 26842 (arthrodesis CMC joint thumb, with or without internal fixation; with or without autograft) and CPT code 26820 (fusion in opposition, thumb, with autogenous graft).

Overall procedure volume data are reported as number of patients with the given CPT code in the database output in a given year. Age-group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who underwent the CPT code of interest that year. Mean charges and reimbursements are reported as results by the database for the code of interest (CPT 25447). Data for the region analysis are presented as an incidence, as there is an uneven distribution of patient volumes among regions. This incidence is calculated as number of patients in a particular region and year normalized to total number of patients in the database for that particular region or year. Regions are defined as Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MS, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-squared linear-by-linear association analysis was used to determine statistical significance with regard to trends over time in procedure volumes, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

Results

In the database, we identified 41,171 unique patients who underwent CMC interposition arthroplasty between 2005 and 2011. Over the 7-year study period, number of patients who had CMC interposition arthroplasty increased 46.2%, from 4761 in 2005 to 6960 in 2011 (P < .0001) (Table 1, Figure 1). Throughout this period, females underwent CMC interposition arthroplasty more frequently than males at all time points (P < .0001). Overall ratio of female to male patients, however, changed significantly. In 2005, 18.1% of all CMC interposition arthroplasties were performed on male patients; this increased to 23.9% of all procedures by 2011 (P < .0001) (Figure 2). Table 1 presents an age-group analysis. There were no significant differences in relative percentage of patients in any given age group who underwent CMC interposition arthroplasty over the study period.

Analysis of overall procedure incidence by region revealed significant increases in all regions (P < .0001), ranging from 18.5% (West) to 54.5% (Northeast) (Figure 3). At all time points, the incidence of CMC interposition arthroplasty was significantly lower in the Northeast than in any other region and compared with the overall average.

Between 2005 and 2011, there were significant increases in both per-patient charges and reimbursements for CMC interposition arthroplasty (Figure 4). Mean per-patient charge increased from $2676 in 2005 to $4181 in 2011 (P < .0001), and mean per-patient reimbursement increased from $1445 in 2005 to $2061 in 2011 (P < .0001). The discrepancy between charge and reimbursement increased throughout the study period: Reimbursement in 2005 was 54.0% of the charge; this decreased to 49.3% by 2011 but was not statistically significant (P = .08).

Overall, 40.9% of patients who underwent CMC interposition arthroplasty also had a CTS diagnosis. Between 15.5% and 17.3% of these patients had concomitant open or endoscopic CTR at time of CMC interposition arthroplasty (Table 2). Percentage of patients who underwent concomitant CTR did not change significantly from 2005 to 2011 (P = .139). Use of postoperative occupational and/or physical therapy increased significantly over the study period, from 33.5% of patients in 2005 to 50.7% of patients in 2010 (P < .0001). Use of postoperative thumb, hand, and/or wrist radiography also increased throughout the study period, from 7.4% of patients in 2005 to 18.7% of patients in 2010 (P < .0001).

We identified 1916 unique patients who underwent thumb CMC arthrodesis between 2005 and 2011. Over the 7-year study period, there was a 19.1% decrease in number of patients who underwent CMC arthrodesis, from 309 in 2005 to 250 in 2011 (P < .0001) (Figure 5). Significantly fewer patients had CMC arthrodesis compared with CMC interposition arthroplasty at all time points, ranging from 6.5% (thumb CMC arthrodesis:CMC interposition arthroplasty) in 2005 to 3.6% in 2011 (P < .0001).

Discussion

Our results demonstrated a significant increase in use of thumb CMC interposition arthroplasty in a US Medicare population, with an increase of more than 46% from 2005 to 2011. This finding supports the findings of a recent cross-sectional survey-based study in which 719 (62%) of 1156 surveyed US hand surgeons reported performing trapeziectomy with LRTI for advanced thumb CMC-OA.²¹ A prior study had similar findings, with 692 (68%) of 1024 American Society for Surgery of the Hand (ASSH) members performing LRTI and 766 (75%) of 1024 performing some type of CMC interposition with trapeziectomy for advanced CMC-OA.²³ This preference for CMC interposition arthroplasty prevails despite the fact that numerous studies have shown no superiority of any surgical procedure to another for CMC-OA in terms of pain, function, satisfaction, range of motion, and strength.^{7,15,18,19,24-34} Our data demonstrated that, not only does CMC interposition arthroplasty remain the most frequently used procedure for thumb CMC-OA, the incidence of CMC interposition arthroplasty continues to increase yearly.

The incidence of thumb CMC-OA is higher in women than in men, with more joint laxity a known contributor and subtle sex differences in trapezium geometry and congruence postulated as additional factors.^3,35,36 This trend was confirmed in the present study, as females underwent significantly more CMC interposition arthroplasties at all time points. It is interesting that the overall ratio of female to male patients changed significantly over the study period, with the percentage of patients who were male increasing from 18.1% in 2005 to 23.9% in 2011. No previous studies have captured such a large cross section of the population to establish this trend. Although this trend is not necessarily intuitive, potential theories include increased acceptance of CMC interposition arthroplasty as a surgical option for male patients, and potentially a larger number of male patients seeking medical care for thumb CMC-OA in recent years.

Increases in procedure incidence were noted in all regions of the United States, but the largest percentage increase occurred in the Northeast. Despite this increase, the Northeast also had significantly lower CMC interposition arthroplasty incidence compared with all other regions and with the average procedure incidence throughout the study period—demonstrating some regional bias as to treatment of thumb CMC-OA. Unfortunately, because of database limitations and lack of specific CPT codes for other treatment options for thumb CMC-OA, we cannot ascertain if other types of surgery are more frequently used in the Northeast.

CTS and thumb CMC-OA often coexist.³⁷ The estimated incidence of concomitant CTS in patients with CMC-OA is between 4% and 43%, but the rate of concomitant CTR and CMC interposition arthroplasty was not previously characterized in the literature.^38,39 Results of the present study supported these findings; 41% of patients who underwent CMC interposition arthroplasty in our study also had a CTS diagnosis, compared with 43% in the 246-patient study by Florack and colleagues.³⁸ We also found that 16% to 17% of patients who underwent CMC interposition arthroplasty underwent concomitant CTR; this rate remained consistent throughout the study period.

Our study demonstrated that, compared with CMC interposition arthroplasties, significantly fewer thumb CMC arthrodesis procedures were performed in the same Medicare population during the same period. Furthermore, the number of thumb CMC arthrodesis procedures declined yearly, with an overall decrease of 19% from 2005 to 2011. In a recent single-blinded, randomized trial, Vermeulen and colleagues⁴⁰ compared thumb CMC arthrodesis and trapeziectomy with LRTI. They found superior patient satisfaction and significantly lower complication rates in women who underwent LRTI versus arthrodesis. The study was terminated prematurely because of these complications and thus was underpowered to determine differences in specific outcome measures. Previous studies comparing arthrodesis and interposition arthroplasties reported inconsistent outcomes. Hart and colleagues⁴¹ found no significant differences in pain or function between CMC arthrodesis and LRTI at a mean 7-year follow-up in a level II randomized controlled trial. Hartigan and colleagues¹⁵ reached similar conclusions in their retrospective comparison of the procedures. Without clear evidence supporting arthrodesis over interposition arthroplasty, the majority of surgeons favor interposition arthroplasty for thumb CMC-OA. Among Medicare patients, use of thumb CMC arthrodesis continues to fall.

This national database study had several limitations, which are common to all studies using the PearlDiver database^22,42-47:

1. The power of the analysis depended on the quality of available data. Potential sources of error included accuracy of billing codes, and miscoding or noncoding by physicians.⁴⁶

2. Although we used this database to try to accurately represent a large population of interest, we cannot guarantee the database represented a true cross section of the United States.

3. For the Medicare population, the PearlDiver database indexes data only in 7-year increments. Although the study period was long enough to detect significant trends, some data may not be accurately captured over a 7-year period.

4. Patients were not randomized to a treatment group.

5. The PearlDiver database does not include any clinical outcome data. Therefore, we cannot comment on the efficacy of the reported evaluations and interventions.

6. There is no specific CPT code for thumb CMC interposition arthroplasty. However, we are unaware of a CMC interposition arthroplasty performed for any area besides the thumb. Theoretically, the study population can include a negligible percentage of patients who had interposition arthroplasty of a CMC joint other than the thumb.

7. The database cannot be searched for use of thumb CMC-OA surgical techniques other than CMC interposition arthroplasty or arthrodesis, as isolated trapeziectomy, volar ligament reconstruction, implant arthroplasty, and metacarpal osteotomy lack specific CPT codes.

Conclusion

Thumb CMC-OA is a common entity among Medicare patients. There are numerous surgical options for cases that have failed conservative treatment. Despite the lack of evidence that thumb CMC interposition arthroplasty is superior to other surgical options, the number of patients who had this procedure increased 46% during the 2005–2011 study period. Although the majority of patients who undergo CMC interposition arthroplasty are female, the percentage of male patients has increased significantly. More than 40% of patients who have CMC interposition arthroplasty are also diagnosed with CTS, and 16% to 17% of patients who have CMC interposition arthroplasty will have a concomitant CTR. CMC arthrodesis is used in significantly fewer patients of Medicare age, and its use has been declining.

A common entity, osteoarthritis (OA) at the base of the thumb is largely caused by the unique anatomy and biomechanics of the thumb carpometacarpal (CMC) joint.¹ Radiographically evident CMC degeneration occurs in 40% of women and 25% of men over age 75 years, making the thumb CMC joint the most common site of surgical reconstruction for upper extremity OA.^2,3

Over the past 40 years, numerous surgical techniques for managing thumb CMC-OA have been described. These include volar ligament reconstruction, first metacarpal osteotomy, CMC arthrodesis, CMC joint replacement, and trapeziectomy. Trapeziectomy can be performed in isolation or in combination with tendon interposition, ligament reconstruction, or ligament reconstruction and tendon interposition (LRTI).^4-20 The authors of a recent systematic review concluded there is no evidence that any one surgical procedure for CMC-OA is superior to another in terms of pain, function, satisfaction, range of motion, or strength.⁴ Nevertheless, a recent survey found that 719 (62%) of 1156 US hand surgeons used LRTI as the treatment of choice for advanced CMC-OA.²¹

Our detailed literature search yielded no other database studies characterizing current trends in the practice patterns of US orthopedic surgeons who perform interposition arthroplasty for CMC arthritis. Analysis of these trends is important not only to patients but also to the broader orthopedic and health care community.²²

We conducted a study to investigate current trends in CMC interposition arthroplasty across time, sex, age, and region of the United States; per-patient charges and reimbursements; and the association between this procedure and concomitantly performed carpal tunnel syndrome (CTS) and carpal tunnel release (CTR). In addition, we compared incidence of CMC interposition arthroplasty with that of CMC arthrodesis.

Patients and Methods

All data were derived from the PearlDiver Patient Records Database (PearlDiver Technologies), a publicly available database of patients. The database stores procedure volumes, demographics, and average charge information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the present study were drawn from the Medicare database within the PearlDiver records, which has a total of 179,094,296 patient records covering the period 2005–2011. This study did not require institutional review board approval, as it used existing, publicly available data without identifiers linked to subjects.

PearlDiver Technologies granted us database access for academic research. The database was stored on a password-protected server maintained by PearlDiver. ICD-9 and CPT codes can be searched in isolation or in combination. Search results yield number of patients with a searched code (or combination of codes) in each year, age group, or region of the United States, as well as mean charge and mean reimbursement for the code or combination of codes.

We used CPT code 25447 (arthroplasty, interposition, intercarpal, or CMC joints) to search the database for patients who underwent thumb CMC interposition arthroplasty. Although this code does not specify thumb, we are unaware of any procedure (other than thumb CMC interposition arthroplasty) typically given this code. Our search yielded procedure volumes, sex distribution, age distribution, region volumes, and mean per-patient charges and reimbursements for each CPT code. We then searched the resulting cohort for CTS (ICD-9 code 354.0), endoscopic CTR (CPT code 29848), and open CTR (CPT code 64721) to find CTR performed concomitantly with CMC interposition arthroplasty. Last, patients were tracked in the database past their surgery date to evaluate for postoperative physical or occupational therapy evaluations within 6 months (using CPT codes appearing in at least 1% of the cohort: 97001, 97003, 97004, 97110, 97112, 97124, 97140, 97150, 97350, 97535) and postoperative thumb, hand, or wrist radiographs within 6 months (using CPT codes appearing in at least 1% of the cohort: 73140, 73130, 73110). To ensure adequacy of 6-month postoperative data, we included in this portion of the study only those patients with surgery dates between 2005 and 2010.

For comparative purposes, we also searched the database for patients who underwent thumb CMC arthrodesis within the same period—using CPT codes 26841 and 26842 (arthrodesis CMC joint thumb, with or without internal fixation; with or without autograft) and CPT code 26820 (fusion in opposition, thumb, with autogenous graft).

Overall procedure volume data are reported as number of patients with the given CPT code in the database output in a given year. Age-group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who underwent the CPT code of interest that year. Mean charges and reimbursements are reported as results by the database for the code of interest (CPT 25447). Data for the region analysis are presented as an incidence, as there is an uneven distribution of patient volumes among regions. This incidence is calculated as number of patients in a particular region and year normalized to total number of patients in the database for that particular region or year. Regions are defined as Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MS, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-squared linear-by-linear association analysis was used to determine statistical significance with regard to trends over time in procedure volumes, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

Results

In the database, we identified 41,171 unique patients who underwent CMC interposition arthroplasty between 2005 and 2011. Over the 7-year study period, number of patients who had CMC interposition arthroplasty increased 46.2%, from 4761 in 2005 to 6960 in 2011 (P < .0001) (Table 1, Figure 1). Throughout this period, females underwent CMC interposition arthroplasty more frequently than males at all time points (P < .0001). Overall ratio of female to male patients, however, changed significantly. In 2005, 18.1% of all CMC interposition arthroplasties were performed on male patients; this increased to 23.9% of all procedures by 2011 (P < .0001) (Figure 2). Table 1 presents an age-group analysis. There were no significant differences in relative percentage of patients in any given age group who underwent CMC interposition arthroplasty over the study period.

Analysis of overall procedure incidence by region revealed significant increases in all regions (P < .0001), ranging from 18.5% (West) to 54.5% (Northeast) (Figure 3). At all time points, the incidence of CMC interposition arthroplasty was significantly lower in the Northeast than in any other region and compared with the overall average.

Between 2005 and 2011, there were significant increases in both per-patient charges and reimbursements for CMC interposition arthroplasty (Figure 4). Mean per-patient charge increased from $2676 in 2005 to $4181 in 2011 (P < .0001), and mean per-patient reimbursement increased from $1445 in 2005 to $2061 in 2011 (P < .0001). The discrepancy between charge and reimbursement increased throughout the study period: Reimbursement in 2005 was 54.0% of the charge; this decreased to 49.3% by 2011 but was not statistically significant (P = .08).

Overall, 40.9% of patients who underwent CMC interposition arthroplasty also had a CTS diagnosis. Between 15.5% and 17.3% of these patients had concomitant open or endoscopic CTR at time of CMC interposition arthroplasty (Table 2). Percentage of patients who underwent concomitant CTR did not change significantly from 2005 to 2011 (P = .139). Use of postoperative occupational and/or physical therapy increased significantly over the study period, from 33.5% of patients in 2005 to 50.7% of patients in 2010 (P < .0001). Use of postoperative thumb, hand, and/or wrist radiography also increased throughout the study period, from 7.4% of patients in 2005 to 18.7% of patients in 2010 (P < .0001).

We identified 1916 unique patients who underwent thumb CMC arthrodesis between 2005 and 2011. Over the 7-year study period, there was a 19.1% decrease in number of patients who underwent CMC arthrodesis, from 309 in 2005 to 250 in 2011 (P < .0001) (Figure 5). Significantly fewer patients had CMC arthrodesis compared with CMC interposition arthroplasty at all time points, ranging from 6.5% (thumb CMC arthrodesis:CMC interposition arthroplasty) in 2005 to 3.6% in 2011 (P < .0001).

Discussion

Our results demonstrated a significant increase in use of thumb CMC interposition arthroplasty in a US Medicare population, with an increase of more than 46% from 2005 to 2011. This finding supports the findings of a recent cross-sectional survey-based study in which 719 (62%) of 1156 surveyed US hand surgeons reported performing trapeziectomy with LRTI for advanced thumb CMC-OA.²¹ A prior study had similar findings, with 692 (68%) of 1024 American Society for Surgery of the Hand (ASSH) members performing LRTI and 766 (75%) of 1024 performing some type of CMC interposition with trapeziectomy for advanced CMC-OA.²³ This preference for CMC interposition arthroplasty prevails despite the fact that numerous studies have shown no superiority of any surgical procedure to another for CMC-OA in terms of pain, function, satisfaction, range of motion, and strength.^{7,15,18,19,24-34} Our data demonstrated that, not only does CMC interposition arthroplasty remain the most frequently used procedure for thumb CMC-OA, the incidence of CMC interposition arthroplasty continues to increase yearly.

The incidence of thumb CMC-OA is higher in women than in men, with more joint laxity a known contributor and subtle sex differences in trapezium geometry and congruence postulated as additional factors.^3,35,36 This trend was confirmed in the present study, as females underwent significantly more CMC interposition arthroplasties at all time points. It is interesting that the overall ratio of female to male patients changed significantly over the study period, with the percentage of patients who were male increasing from 18.1% in 2005 to 23.9% in 2011. No previous studies have captured such a large cross section of the population to establish this trend. Although this trend is not necessarily intuitive, potential theories include increased acceptance of CMC interposition arthroplasty as a surgical option for male patients, and potentially a larger number of male patients seeking medical care for thumb CMC-OA in recent years.

Increases in procedure incidence were noted in all regions of the United States, but the largest percentage increase occurred in the Northeast. Despite this increase, the Northeast also had significantly lower CMC interposition arthroplasty incidence compared with all other regions and with the average procedure incidence throughout the study period—demonstrating some regional bias as to treatment of thumb CMC-OA. Unfortunately, because of database limitations and lack of specific CPT codes for other treatment options for thumb CMC-OA, we cannot ascertain if other types of surgery are more frequently used in the Northeast.

CTS and thumb CMC-OA often coexist.³⁷ The estimated incidence of concomitant CTS in patients with CMC-OA is between 4% and 43%, but the rate of concomitant CTR and CMC interposition arthroplasty was not previously characterized in the literature.^38,39 Results of the present study supported these findings; 41% of patients who underwent CMC interposition arthroplasty in our study also had a CTS diagnosis, compared with 43% in the 246-patient study by Florack and colleagues.³⁸ We also found that 16% to 17% of patients who underwent CMC interposition arthroplasty underwent concomitant CTR; this rate remained consistent throughout the study period.

Our study demonstrated that, compared with CMC interposition arthroplasties, significantly fewer thumb CMC arthrodesis procedures were performed in the same Medicare population during the same period. Furthermore, the number of thumb CMC arthrodesis procedures declined yearly, with an overall decrease of 19% from 2005 to 2011. In a recent single-blinded, randomized trial, Vermeulen and colleagues⁴⁰ compared thumb CMC arthrodesis and trapeziectomy with LRTI. They found superior patient satisfaction and significantly lower complication rates in women who underwent LRTI versus arthrodesis. The study was terminated prematurely because of these complications and thus was underpowered to determine differences in specific outcome measures. Previous studies comparing arthrodesis and interposition arthroplasties reported inconsistent outcomes. Hart and colleagues⁴¹ found no significant differences in pain or function between CMC arthrodesis and LRTI at a mean 7-year follow-up in a level II randomized controlled trial. Hartigan and colleagues¹⁵ reached similar conclusions in their retrospective comparison of the procedures. Without clear evidence supporting arthrodesis over interposition arthroplasty, the majority of surgeons favor interposition arthroplasty for thumb CMC-OA. Among Medicare patients, use of thumb CMC arthrodesis continues to fall.

This national database study had several limitations, which are common to all studies using the PearlDiver database^22,42-47:

1. The power of the analysis depended on the quality of available data. Potential sources of error included accuracy of billing codes, and miscoding or noncoding by physicians.⁴⁶

2. Although we used this database to try to accurately represent a large population of interest, we cannot guarantee the database represented a true cross section of the United States.

3. For the Medicare population, the PearlDiver database indexes data only in 7-year increments. Although the study period was long enough to detect significant trends, some data may not be accurately captured over a 7-year period.

4. Patients were not randomized to a treatment group.

5. The PearlDiver database does not include any clinical outcome data. Therefore, we cannot comment on the efficacy of the reported evaluations and interventions.

6. There is no specific CPT code for thumb CMC interposition arthroplasty. However, we are unaware of a CMC interposition arthroplasty performed for any area besides the thumb. Theoretically, the study population can include a negligible percentage of patients who had interposition arthroplasty of a CMC joint other than the thumb.

7. The database cannot be searched for use of thumb CMC-OA surgical techniques other than CMC interposition arthroplasty or arthrodesis, as isolated trapeziectomy, volar ligament reconstruction, implant arthroplasty, and metacarpal osteotomy lack specific CPT codes.

Conclusion

Thumb CMC-OA is a common entity among Medicare patients. There are numerous surgical options for cases that have failed conservative treatment. Despite the lack of evidence that thumb CMC interposition arthroplasty is superior to other surgical options, the number of patients who had this procedure increased 46% during the 2005–2011 study period. Although the majority of patients who undergo CMC interposition arthroplasty are female, the percentage of male patients has increased significantly. More than 40% of patients who have CMC interposition arthroplasty are also diagnosed with CTS, and 16% to 17% of patients who have CMC interposition arthroplasty will have a concomitant CTR. CMC arthrodesis is used in significantly fewer patients of Medicare age, and its use has been declining.

Gamekeeper’s or skier’s thumb is caused by an injury to the ulnar collateral ligament (UCL) of the metacarpophalangeal (MCP) joint of the thumb. The mechanism of injury is forced radial and palmar abduction and hyperextension.

This lesion was initially described in 1955 by Campbell.¹ It occurred in gamekeepers who worked in preserves in Scotland. The UCL was injured because of the way they killed rabbits—hence, gamekeeper’s thumb. Now these injuries are more common in skiers—skier’s thumb. In skiers, the mechanism of injury is the force exerted by the ski pole strap on the thumb during a fall. This injury is also seen in breakdancers.^1,2

Different lesions can result, the most common being that of the UCL. The UCL lesion may be partial, with no joint instability,^3,4 or total, with instability and subdislocation of the proximal phalanx.^5-9 Rupture of the thumb adductor aponeurosis and displacement of the long extensor have been described as the cause of thumb instability.^6-8

UCL rupture can occur in its extension or can cause a fracture-tearing in the proximal phalanx.^9-12 Intra-articular fractures are sometimes found. The essential problem in UCL injuries is the impossibility of spontaneous healing once the rupture is complete, because of the Stener effect. (When the UCL ruptures, its proximal part retracts and runs above the fibrous expansion of the adductor muscle, which is interposed between the 2 parts of the ruptured UCL and prevents healing, even if the thumb is immobilized.) In these cases, only surgery can repair the lesion.²

In any thumb injury, particularly one caused by hyperabduction, a UCL lesion should be considered. The main problem is diagnosing sprain severity, which is evidenced by the degree of joint hypermobility. Radiologic examination should be performed in all cases to rule out fracture with tear, posterior capsular tear, palmar plate tear, and palmar subdislocation of the proximal phalanx, all of which are associated with UCL tearing.^7-9

If the diagnosis is suspected, and radiographs show no fracture, comparative radiographs should be obtained in forced valgus.

Technique

We report on a simple, reliable, reproducible method that allows the patient’s thumbs to be compared, under the same force application conditions, on a single radiograph. This technique reduces the patient’s and examiner’s exposure to x-rays and is well tolerated by the patient. Anesthesia for the thumb is usually not necessary.

In each hand, the patient holds a cylindrical object, such as a drinking glass (standard diameter, 7.5-8.5 cm). We use an elastic crepe bandage roll (diameter, 7.5 cm; width, 10 cm). This roll is common in emergency departments (EDs) and easily accessible. The patient holds the rolls in his or her hands with the thumbs in the posteroanterior position (Figures 1–3) and places himself or herself on a 18×24-cm frame or directly on the radiography table.

Both thumbs are captured on a single functional radiograph for comparison of forced valgus of the MCP joints, as in our example cases. The patients provided written informed consent for print and electronic publication of these case reports.

Case Reports

Control Case

The single functional radiograph of both thumbs showed no evidence of joint laxity on the valgus stress test (Figure 4).

Case 1

A 72-year-old woman landed on her left hand when she fell backward while supporting the hand on a piece of furniture. She presented to the ED with pain in the region of the thumb and thenar eminence. Posteroanterior and lateral radiograph projections showed no significant bone injury (Figure 5). Given the patient’s persistent pain, the traumatologist suspected damage to the thumb UCL, so a simultaneous bilateral functional radiographic projection was obtained. The projection showed joint laxity, implying damage to the thumb UCL. Repair and reinsertion of the UCL were performed using a bone harpoon suture.

Case 2

A 58-year-old man sustained a left hand injury when, using both hands, he tried to catch hold of a falling wooden plank. When he presented to the ED the following week, he was given a diagnosis of thumb contusion and forced hyperabduction and was wearing a metal strap for immobilization. Radiographs showed no bone damage (Figure 6). Thumb UCL injury was suspected on the basis of the physical examination findings and the mechanism of injury. A bilateral simultaneous functional radiographic projection showed significant joint laxity. Surgical treatment with the pull-out technique was performed.

Case 3

A 44-year-old woman experienced forced traction from a dog leash and presented to the ED with pain in the right thumb region. Radiographs showed no bone damage (Figure 7). Thumb UCL injury was suspected. A bilateral simultaneous functional radiographic projection showed slight joint laxity, a sprain was diagnosed, and plaster bandaging was applied. Figures 8A–8D show the accurate thumb positions for performing the functional radiograph in forced valgus. We call the technique J.J.’s thumb radiographic projection.

Discussion

Examination using the stress test to cause joint tilt is crucial in making an accurate diagnosis and deciding on the most appropriate therapeutic approach.¹⁰ Most authors accept that surgical management is required in joint tilts over 30º, as these involve complete UCL rupture.^10-12

The MCP joint must be examined in flexion, when the main fascicle of the UCL is tight, and not in extension, when the main fascicle of the UCL is relaxed. If we examine the thumb in extension, radial deviations may occur that are not caused by joint instability. Tilt here must be compared with that of the healthy side.¹¹

Early diagnosis and adequate management are essential, as unnoticed or undervalued injuries can progress to painful sequelae, associated with stiffness, instability, and osteoarthritis, with evident harm to the grip and pinch functions of the hand. In many cases, clinical evidence of MCP joint instability is difficult. The radiologic diagnosis is usually obtained with comparative radiographs in forced valgus of both thumbs.

The forced valgus maneuver typically is performed by the examiner, who must stay with the patient in the radiography room and wear radiologic protection. Incredibly, some patients must force the valgus themselves.

The maneuver we have described clearly has complications, as it is painful, and some patients are uncooperative. Usually the thumb is anesthetized, and the examiner assumes the exposure to x-rays. The valgus deviation force that can be applied during stability testing may lead to further disruption of a partially torn ligament or displacement of a ruptured ligament if the overforced maneuver is performed.^13,14 That does not occur with our technique. On the other hand, the forces applied to the thumbs must be symmetrical for comparison purposes. The way to prevent these inconveniences is to perform the forced valgus maneuver over both thumbs simultaneously, under the same force application conditions and on a single radiograph, without requiring the examiner to remain with the patient in the radiography room.

Heim¹⁵ designed a system for simultaneous functional radiographs, but an apparatus must be built to adapt it to the frame of the radiography table, and the technique involves hyperpronating both hands and bandaging them to the forearm—which is uncomfortable and bothersome for patients and, in our opinion, has a poor application in high-volume EDs.

The technique of having the patient hold a bandage roll (J.J.’s thumb radiographic projection) offers several advantages:

1.  The thumb can be placed in flexion, tightening the main fascicle of the UCL, which is how the UCL must be examined.

2. Forced valgus is allowed. Holding a water glass involves opening the thumb and the necessary stability of the MCP joint of the thumb (grip function of thumb); this radiographic technique is functional.

3. The examiner need not stay with the patient in the radiography room or be exposed to x-rays.

4. The bandage roll is thick enough to generate forced valgus in a patient with large hands. The nonrigid roll makes the examination more tolerable and avoids overforced valgus, eliminating the need for anesthetic blockade.

5. The technique is accessible and simple. In fact, there is no need to remove the roll from its wrapping.

Gamekeeper’s or skier’s thumb is caused by an injury to the ulnar collateral ligament (UCL) of the metacarpophalangeal (MCP) joint of the thumb. The mechanism of injury is forced radial and palmar abduction and hyperextension.

This lesion was initially described in 1955 by Campbell.¹ It occurred in gamekeepers who worked in preserves in Scotland. The UCL was injured because of the way they killed rabbits—hence, gamekeeper’s thumb. Now these injuries are more common in skiers—skier’s thumb. In skiers, the mechanism of injury is the force exerted by the ski pole strap on the thumb during a fall. This injury is also seen in breakdancers.^1,2

Different lesions can result, the most common being that of the UCL. The UCL lesion may be partial, with no joint instability,^3,4 or total, with instability and subdislocation of the proximal phalanx.^5-9 Rupture of the thumb adductor aponeurosis and displacement of the long extensor have been described as the cause of thumb instability.^6-8

UCL rupture can occur in its extension or can cause a fracture-tearing in the proximal phalanx.^9-12 Intra-articular fractures are sometimes found. The essential problem in UCL injuries is the impossibility of spontaneous healing once the rupture is complete, because of the Stener effect. (When the UCL ruptures, its proximal part retracts and runs above the fibrous expansion of the adductor muscle, which is interposed between the 2 parts of the ruptured UCL and prevents healing, even if the thumb is immobilized.) In these cases, only surgery can repair the lesion.²

In any thumb injury, particularly one caused by hyperabduction, a UCL lesion should be considered. The main problem is diagnosing sprain severity, which is evidenced by the degree of joint hypermobility. Radiologic examination should be performed in all cases to rule out fracture with tear, posterior capsular tear, palmar plate tear, and palmar subdislocation of the proximal phalanx, all of which are associated with UCL tearing.^7-9

If the diagnosis is suspected, and radiographs show no fracture, comparative radiographs should be obtained in forced valgus.

Technique

We report on a simple, reliable, reproducible method that allows the patient’s thumbs to be compared, under the same force application conditions, on a single radiograph. This technique reduces the patient’s and examiner’s exposure to x-rays and is well tolerated by the patient. Anesthesia for the thumb is usually not necessary.

In each hand, the patient holds a cylindrical object, such as a drinking glass (standard diameter, 7.5-8.5 cm). We use an elastic crepe bandage roll (diameter, 7.5 cm; width, 10 cm). This roll is common in emergency departments (EDs) and easily accessible. The patient holds the rolls in his or her hands with the thumbs in the posteroanterior position (Figures 1–3) and places himself or herself on a 18×24-cm frame or directly on the radiography table.

Both thumbs are captured on a single functional radiograph for comparison of forced valgus of the MCP joints, as in our example cases. The patients provided written informed consent for print and electronic publication of these case reports.

Case Reports

Control Case

The single functional radiograph of both thumbs showed no evidence of joint laxity on the valgus stress test (Figure 4).

Case 1

A 72-year-old woman landed on her left hand when she fell backward while supporting the hand on a piece of furniture. She presented to the ED with pain in the region of the thumb and thenar eminence. Posteroanterior and lateral radiograph projections showed no significant bone injury (Figure 5). Given the patient’s persistent pain, the traumatologist suspected damage to the thumb UCL, so a simultaneous bilateral functional radiographic projection was obtained. The projection showed joint laxity, implying damage to the thumb UCL. Repair and reinsertion of the UCL were performed using a bone harpoon suture.

Case 2

A 58-year-old man sustained a left hand injury when, using both hands, he tried to catch hold of a falling wooden plank. When he presented to the ED the following week, he was given a diagnosis of thumb contusion and forced hyperabduction and was wearing a metal strap for immobilization. Radiographs showed no bone damage (Figure 6). Thumb UCL injury was suspected on the basis of the physical examination findings and the mechanism of injury. A bilateral simultaneous functional radiographic projection showed significant joint laxity. Surgical treatment with the pull-out technique was performed.

Case 3

A 44-year-old woman experienced forced traction from a dog leash and presented to the ED with pain in the right thumb region. Radiographs showed no bone damage (Figure 7). Thumb UCL injury was suspected. A bilateral simultaneous functional radiographic projection showed slight joint laxity, a sprain was diagnosed, and plaster bandaging was applied. Figures 8A–8D show the accurate thumb positions for performing the functional radiograph in forced valgus. We call the technique J.J.’s thumb radiographic projection.

Discussion

Examination using the stress test to cause joint tilt is crucial in making an accurate diagnosis and deciding on the most appropriate therapeutic approach.¹⁰ Most authors accept that surgical management is required in joint tilts over 30º, as these involve complete UCL rupture.^10-12

The MCP joint must be examined in flexion, when the main fascicle of the UCL is tight, and not in extension, when the main fascicle of the UCL is relaxed. If we examine the thumb in extension, radial deviations may occur that are not caused by joint instability. Tilt here must be compared with that of the healthy side.¹¹

Early diagnosis and adequate management are essential, as unnoticed or undervalued injuries can progress to painful sequelae, associated with stiffness, instability, and osteoarthritis, with evident harm to the grip and pinch functions of the hand. In many cases, clinical evidence of MCP joint instability is difficult. The radiologic diagnosis is usually obtained with comparative radiographs in forced valgus of both thumbs.

The forced valgus maneuver typically is performed by the examiner, who must stay with the patient in the radiography room and wear radiologic protection. Incredibly, some patients must force the valgus themselves.

The maneuver we have described clearly has complications, as it is painful, and some patients are uncooperative. Usually the thumb is anesthetized, and the examiner assumes the exposure to x-rays. The valgus deviation force that can be applied during stability testing may lead to further disruption of a partially torn ligament or displacement of a ruptured ligament if the overforced maneuver is performed.^13,14 That does not occur with our technique. On the other hand, the forces applied to the thumbs must be symmetrical for comparison purposes. The way to prevent these inconveniences is to perform the forced valgus maneuver over both thumbs simultaneously, under the same force application conditions and on a single radiograph, without requiring the examiner to remain with the patient in the radiography room.

Heim¹⁵ designed a system for simultaneous functional radiographs, but an apparatus must be built to adapt it to the frame of the radiography table, and the technique involves hyperpronating both hands and bandaging them to the forearm—which is uncomfortable and bothersome for patients and, in our opinion, has a poor application in high-volume EDs.

The technique of having the patient hold a bandage roll (J.J.’s thumb radiographic projection) offers several advantages:

1.  The thumb can be placed in flexion, tightening the main fascicle of the UCL, which is how the UCL must be examined.

2. Forced valgus is allowed. Holding a water glass involves opening the thumb and the necessary stability of the MCP joint of the thumb (grip function of thumb); this radiographic technique is functional.

3. The examiner need not stay with the patient in the radiography room or be exposed to x-rays.

4. The bandage roll is thick enough to generate forced valgus in a patient with large hands. The nonrigid roll makes the examination more tolerable and avoids overforced valgus, eliminating the need for anesthetic blockade.

5. The technique is accessible and simple. In fact, there is no need to remove the roll from its wrapping.

Gamekeeper’s or skier’s thumb is caused by an injury to the ulnar collateral ligament (UCL) of the metacarpophalangeal (MCP) joint of the thumb. The mechanism of injury is forced radial and palmar abduction and hyperextension.

This lesion was initially described in 1955 by Campbell.¹ It occurred in gamekeepers who worked in preserves in Scotland. The UCL was injured because of the way they killed rabbits—hence, gamekeeper’s thumb. Now these injuries are more common in skiers—skier’s thumb. In skiers, the mechanism of injury is the force exerted by the ski pole strap on the thumb during a fall. This injury is also seen in breakdancers.^1,2

Different lesions can result, the most common being that of the UCL. The UCL lesion may be partial, with no joint instability,^3,4 or total, with instability and subdislocation of the proximal phalanx.^5-9 Rupture of the thumb adductor aponeurosis and displacement of the long extensor have been described as the cause of thumb instability.^6-8

UCL rupture can occur in its extension or can cause a fracture-tearing in the proximal phalanx.^9-12 Intra-articular fractures are sometimes found. The essential problem in UCL injuries is the impossibility of spontaneous healing once the rupture is complete, because of the Stener effect. (When the UCL ruptures, its proximal part retracts and runs above the fibrous expansion of the adductor muscle, which is interposed between the 2 parts of the ruptured UCL and prevents healing, even if the thumb is immobilized.) In these cases, only surgery can repair the lesion.²

In any thumb injury, particularly one caused by hyperabduction, a UCL lesion should be considered. The main problem is diagnosing sprain severity, which is evidenced by the degree of joint hypermobility. Radiologic examination should be performed in all cases to rule out fracture with tear, posterior capsular tear, palmar plate tear, and palmar subdislocation of the proximal phalanx, all of which are associated with UCL tearing.^7-9

If the diagnosis is suspected, and radiographs show no fracture, comparative radiographs should be obtained in forced valgus.

Technique

We report on a simple, reliable, reproducible method that allows the patient’s thumbs to be compared, under the same force application conditions, on a single radiograph. This technique reduces the patient’s and examiner’s exposure to x-rays and is well tolerated by the patient. Anesthesia for the thumb is usually not necessary.

In each hand, the patient holds a cylindrical object, such as a drinking glass (standard diameter, 7.5-8.5 cm). We use an elastic crepe bandage roll (diameter, 7.5 cm; width, 10 cm). This roll is common in emergency departments (EDs) and easily accessible. The patient holds the rolls in his or her hands with the thumbs in the posteroanterior position (Figures 1–3) and places himself or herself on a 18×24-cm frame or directly on the radiography table.

Both thumbs are captured on a single functional radiograph for comparison of forced valgus of the MCP joints, as in our example cases. The patients provided written informed consent for print and electronic publication of these case reports.

Case Reports

Control Case

The single functional radiograph of both thumbs showed no evidence of joint laxity on the valgus stress test (Figure 4).

Case 1

A 72-year-old woman landed on her left hand when she fell backward while supporting the hand on a piece of furniture. She presented to the ED with pain in the region of the thumb and thenar eminence. Posteroanterior and lateral radiograph projections showed no significant bone injury (Figure 5). Given the patient’s persistent pain, the traumatologist suspected damage to the thumb UCL, so a simultaneous bilateral functional radiographic projection was obtained. The projection showed joint laxity, implying damage to the thumb UCL. Repair and reinsertion of the UCL were performed using a bone harpoon suture.

Case 2

A 58-year-old man sustained a left hand injury when, using both hands, he tried to catch hold of a falling wooden plank. When he presented to the ED the following week, he was given a diagnosis of thumb contusion and forced hyperabduction and was wearing a metal strap for immobilization. Radiographs showed no bone damage (Figure 6). Thumb UCL injury was suspected on the basis of the physical examination findings and the mechanism of injury. A bilateral simultaneous functional radiographic projection showed significant joint laxity. Surgical treatment with the pull-out technique was performed.

Case 3

A 44-year-old woman experienced forced traction from a dog leash and presented to the ED with pain in the right thumb region. Radiographs showed no bone damage (Figure 7). Thumb UCL injury was suspected. A bilateral simultaneous functional radiographic projection showed slight joint laxity, a sprain was diagnosed, and plaster bandaging was applied. Figures 8A–8D show the accurate thumb positions for performing the functional radiograph in forced valgus. We call the technique J.J.’s thumb radiographic projection.

Discussion

Examination using the stress test to cause joint tilt is crucial in making an accurate diagnosis and deciding on the most appropriate therapeutic approach.¹⁰ Most authors accept that surgical management is required in joint tilts over 30º, as these involve complete UCL rupture.^10-12

The MCP joint must be examined in flexion, when the main fascicle of the UCL is tight, and not in extension, when the main fascicle of the UCL is relaxed. If we examine the thumb in extension, radial deviations may occur that are not caused by joint instability. Tilt here must be compared with that of the healthy side.¹¹

Early diagnosis and adequate management are essential, as unnoticed or undervalued injuries can progress to painful sequelae, associated with stiffness, instability, and osteoarthritis, with evident harm to the grip and pinch functions of the hand. In many cases, clinical evidence of MCP joint instability is difficult. The radiologic diagnosis is usually obtained with comparative radiographs in forced valgus of both thumbs.

The forced valgus maneuver typically is performed by the examiner, who must stay with the patient in the radiography room and wear radiologic protection. Incredibly, some patients must force the valgus themselves.

The maneuver we have described clearly has complications, as it is painful, and some patients are uncooperative. Usually the thumb is anesthetized, and the examiner assumes the exposure to x-rays. The valgus deviation force that can be applied during stability testing may lead to further disruption of a partially torn ligament or displacement of a ruptured ligament if the overforced maneuver is performed.^13,14 That does not occur with our technique. On the other hand, the forces applied to the thumbs must be symmetrical for comparison purposes. The way to prevent these inconveniences is to perform the forced valgus maneuver over both thumbs simultaneously, under the same force application conditions and on a single radiograph, without requiring the examiner to remain with the patient in the radiography room.

Heim¹⁵ designed a system for simultaneous functional radiographs, but an apparatus must be built to adapt it to the frame of the radiography table, and the technique involves hyperpronating both hands and bandaging them to the forearm—which is uncomfortable and bothersome for patients and, in our opinion, has a poor application in high-volume EDs.

The technique of having the patient hold a bandage roll (J.J.’s thumb radiographic projection) offers several advantages:

1.  The thumb can be placed in flexion, tightening the main fascicle of the UCL, which is how the UCL must be examined.

2. Forced valgus is allowed. Holding a water glass involves opening the thumb and the necessary stability of the MCP joint of the thumb (grip function of thumb); this radiographic technique is functional.

3. The examiner need not stay with the patient in the radiography room or be exposed to x-rays.

4. The bandage roll is thick enough to generate forced valgus in a patient with large hands. The nonrigid roll makes the examination more tolerable and avoids overforced valgus, eliminating the need for anesthetic blockade.

5. The technique is accessible and simple. In fact, there is no need to remove the roll from its wrapping.

Total knee arthroplasty provides osteoarthritis patients with greater improvement in pain and health-related quality of life than it does for rheumatoid arthritis patients, possibly relating to the lower pain and younger age of RA patients at the time of surgery, according to a study based on patients’ responses to semiannual questionnaires.

The study included 834 patients diagnosed with RA and 315 patients diagnosed with osteoarthritis (OA), who had a primary total knee arthroplasty (TKA) between Jan. 1, 1999, and June 30, 2012. The patients were probed on their demographic characteristics, disease duration, mental health, functional status, health-related quality of life (HRQoL), pain, and usage of pain medication. All study participants participated in at least three consecutive sampling intervals: a 6-month preoperative period, a 6-month immediate postoperative period, and a subsequent 6-month “recovery” period. Of the patients who underwent a TKA, 144 (11%) did not complete all three sampling intervals.

© iStock / ThinkStockPhotos.com

At baseline, compared with OA patients, RA patients had significantly less severe scores for measures of pain, lesser usage of pain medications, and significantly more severe scores for measures of disease activity.

After recovering from a TKA, the RA and OA patients improved in almost all outcome measures of pain, function, and HRQoL. The surgery had a larger beneficial effect in OA patients than in RA patients for all measures of pain and HRQoL indices, except for the RA disease activity index (RADAI)/total joint count. In contrast to the OA patients, RA patients showed greater improvements in joint involvement.

For both groups, all outcome measures of pain and function worsened a year before TKA and improved immediately after the surgery; however, the improvement leveled off in the 6-12 months after the procedure.

“After adjusting for preoperative variables, post TKA, a diagnosis of RA (vs. OA) (P = .03), income (P < .01), and anxiety (P = .03) were most useful in predicting the reduction in [visual analog scale] pain scores,” noted Dr. Anand Dusad of the Veterans Affairs Nebraska–Western Iowa Health Care System, Omaha, and his colleagues.

“In summary, using a large cohort of arthritis patients, we have shown that TKA is performed in patients with severe disease and leads to marked improvements in pain function and HRQoL,” according to the researchers.

Read the full study published online July 20 in Arthritis & Rheumatology (doi:10.1002/art.39221).

klennon@frontlinemedcom.com

Total knee arthroplasty provides osteoarthritis patients with greater improvement in pain and health-related quality of life than it does for rheumatoid arthritis patients, possibly relating to the lower pain and younger age of RA patients at the time of surgery, according to a study based on patients’ responses to semiannual questionnaires.

The study included 834 patients diagnosed with RA and 315 patients diagnosed with osteoarthritis (OA), who had a primary total knee arthroplasty (TKA) between Jan. 1, 1999, and June 30, 2012. The patients were probed on their demographic characteristics, disease duration, mental health, functional status, health-related quality of life (HRQoL), pain, and usage of pain medication. All study participants participated in at least three consecutive sampling intervals: a 6-month preoperative period, a 6-month immediate postoperative period, and a subsequent 6-month “recovery” period. Of the patients who underwent a TKA, 144 (11%) did not complete all three sampling intervals.

© iStock / ThinkStockPhotos.com

At baseline, compared with OA patients, RA patients had significantly less severe scores for measures of pain, lesser usage of pain medications, and significantly more severe scores for measures of disease activity.

After recovering from a TKA, the RA and OA patients improved in almost all outcome measures of pain, function, and HRQoL. The surgery had a larger beneficial effect in OA patients than in RA patients for all measures of pain and HRQoL indices, except for the RA disease activity index (RADAI)/total joint count. In contrast to the OA patients, RA patients showed greater improvements in joint involvement.

For both groups, all outcome measures of pain and function worsened a year before TKA and improved immediately after the surgery; however, the improvement leveled off in the 6-12 months after the procedure.

“After adjusting for preoperative variables, post TKA, a diagnosis of RA (vs. OA) (P = .03), income (P < .01), and anxiety (P = .03) were most useful in predicting the reduction in [visual analog scale] pain scores,” noted Dr. Anand Dusad of the Veterans Affairs Nebraska–Western Iowa Health Care System, Omaha, and his colleagues.

“In summary, using a large cohort of arthritis patients, we have shown that TKA is performed in patients with severe disease and leads to marked improvements in pain function and HRQoL,” according to the researchers.

Read the full study published online July 20 in Arthritis & Rheumatology (doi:10.1002/art.39221).

klennon@frontlinemedcom.com

Total knee arthroplasty provides osteoarthritis patients with greater improvement in pain and health-related quality of life than it does for rheumatoid arthritis patients, possibly relating to the lower pain and younger age of RA patients at the time of surgery, according to a study based on patients’ responses to semiannual questionnaires.

The study included 834 patients diagnosed with RA and 315 patients diagnosed with osteoarthritis (OA), who had a primary total knee arthroplasty (TKA) between Jan. 1, 1999, and June 30, 2012. The patients were probed on their demographic characteristics, disease duration, mental health, functional status, health-related quality of life (HRQoL), pain, and usage of pain medication. All study participants participated in at least three consecutive sampling intervals: a 6-month preoperative period, a 6-month immediate postoperative period, and a subsequent 6-month “recovery” period. Of the patients who underwent a TKA, 144 (11%) did not complete all three sampling intervals.

© iStock / ThinkStockPhotos.com

At baseline, compared with OA patients, RA patients had significantly less severe scores for measures of pain, lesser usage of pain medications, and significantly more severe scores for measures of disease activity.

After recovering from a TKA, the RA and OA patients improved in almost all outcome measures of pain, function, and HRQoL. The surgery had a larger beneficial effect in OA patients than in RA patients for all measures of pain and HRQoL indices, except for the RA disease activity index (RADAI)/total joint count. In contrast to the OA patients, RA patients showed greater improvements in joint involvement.

For both groups, all outcome measures of pain and function worsened a year before TKA and improved immediately after the surgery; however, the improvement leveled off in the 6-12 months after the procedure.

“After adjusting for preoperative variables, post TKA, a diagnosis of RA (vs. OA) (P = .03), income (P < .01), and anxiety (P = .03) were most useful in predicting the reduction in [visual analog scale] pain scores,” noted Dr. Anand Dusad of the Veterans Affairs Nebraska–Western Iowa Health Care System, Omaha, and his colleagues.

“In summary, using a large cohort of arthritis patients, we have shown that TKA is performed in patients with severe disease and leads to marked improvements in pain function and HRQoL,” according to the researchers.

Read the full study published online July 20 in Arthritis & Rheumatology (doi:10.1002/art.39221).

klennon@frontlinemedcom.com

Extensor tendon rupture in chronic Madelung deformity, as a result of tendon attrition on the dislocated distal ulna, occurs infrequently. However, it is often seen in patients with rheumatoid arthritis. This issue has been reported in only a few English-language case reports. Here we report a case of multiple tendon ruptures in a previously undiagnosed Madelung deformity. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 56-year-old active woman presented with 50 days’ inability to extend the fourth and fifth fingers of her dominant right hand. The loss of finger extension progressed, over several weeks, to involve the third finger as well. The first 2 tendon ruptures had been triggered by lifting a light grocery bag, when she noticed a sharp sudden pain and “pop.” The third rupture occurred spontaneously with a snapping sound the night before surgery.

 The patient had observed some prominence on the ulnar side of her right wrist since childhood but had never experienced any pain or functional disability. There was neither history of trauma, inflammatory disease, diabetes mellitus, or infection, nor positive family history of similar wrist deformity.

The physical examination showed a dorsally subluxated distal radioulnar joint, prominent ulnar styloid, and mild ulnar and volar deviation of the wrist along with limitation of wrist dorsiflexion. Complete loss of active extension of the 3 ulnar fingers was demonstrated, while neurovascular status and all other hand evaluations were normal. The wrist radiographs confirmed the typical findings of Madelung deformity (Figure 1).

Repair of the ruptured tendons and resection of the prominent distal ulna (Darrach procedure) was planned. (Given the patient’s age and evidence of degenerative changes in the radiocarpal joint, correction of the Madelung deformity did not seem necessary). At time of surgery, the recently ruptured third finger extensor tendon was easily found and approximated, and end-to-end repair was performed. The fourth and fifth fingers, however, had to be fished out more proximally from dense granulation tissue. After the distal ulna was resected for a distance of 1.5 cm, meticulous repair of the ulnar collateral ligament and the capsule and periosteum over the end of the ulna was performed. Then, for grafting of the ruptured tendons, the extensor indicis proprius tendon was isolated and transected at the second metacarpophalangeal joint level. A piece of this tendon was used as interpositional graft for the fourth extensor tendon, and the main tendon unit was transferred to the fifth finger extensor. The extensor digiti quinti tendon, which was about to rupture, was further reinforced by suturing it side to side to the muscle and tendon of the extensor indicis proprius (Figure 2).

Postoperatively, the wrist was kept in extension in a cast for 3 weeks while the fingers were free for active movement. A removable wrist splint was used for an additional month. At 3-month follow-up, the patient had regained full and strong finger extension and wrist motion.

At 3-year follow-up, the patient was pain-free, and had full extension of all fingers, full forearm rotation, and near-normal motion (better than her preoperative motion). The grip power on the operated right hand was 215 N, and pinch power was 93 N. (The values for the left side were 254 N and 83 N, respectively, using the Jamar hydraulic hand dynamometer [Patterson Medical].) The patient has had no additional tendon rupture (Figure 3).

Discussion

Madelung deformity was first described by Madelung in 1878 and several cases have reported this deformity. However, extensor tendon rupture caused by Madelung deformity is very rare, reported in few cases.¹

Extensor tendon rupture caused by chronic Madelung deformity has been reported few times in the English literature. Goodwin¹ apparently published the first report of such an occurrence in 1979. Ducloyer and colleagues² from France reported 6 cases of extensor tendon rupture as a result of inferior distal radioulnar joint deformity of Madelung. Jebson and colleagues³ reported bilateral spontaneous extensor tendon ruptures in Madelung deformity in 1992.

The mechanism of tendon rupture seems to be mechanical, resulting from continuous rubbing and erosion of tendons over the deformed ulnar head, which has a rough irregular surface⁴ and leads to fraying of the tendons and eventual rupture and retraction of the severed tendon ends. This rupture usually progresses stepwise from more medial to the lateral tendons.² Older patients are, therefore, subject to chronic repetitive attritional trauma leading to tendon rupture.

Tendons may rupture as a result of a variety of conditions, such as chronic synovitis in rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disease, or crystal deposition in gout.^5-8 Some other metabolic or endocrine conditions that involve tendon ruptures include diabetes mellitus, chronic renal failure, and hyperparathyroidism. Steroid injection into the tendons also has a detrimental effect on tendon integrity and may cause tendon tear.⁹ Mechanical factors, such as erosion on bony prominences, are well-known etiologies for tendon rupture, as commonly seen in rheumatoid arthritis, and have been reported in Kienböck disease,¹⁰ thumb carpometacarpal arthritis,¹¹ Colles fracture, scaphoid fracture nonunion,¹² and Madelung deformity.

Conclusion

Our case reflects the usual middle-aged female presentation of such a tendon rupture. The tendon ruptures were spontaneous in the reported order of ulnar to radial, beginning with the little and ring fingers, and progressed radially. The patient had isolated Madelung deformity with no other sign of dyschondrosteosis¹³ or dwarfism, conditions commonly mentioned in association with Madelung deformity. This case report should raise awareness about possible tendon rupture in any chronic case of Madelung deformity.

Extensor tendon rupture in chronic Madelung deformity, as a result of tendon attrition on the dislocated distal ulna, occurs infrequently. However, it is often seen in patients with rheumatoid arthritis. This issue has been reported in only a few English-language case reports. Here we report a case of multiple tendon ruptures in a previously undiagnosed Madelung deformity. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 56-year-old active woman presented with 50 days’ inability to extend the fourth and fifth fingers of her dominant right hand. The loss of finger extension progressed, over several weeks, to involve the third finger as well. The first 2 tendon ruptures had been triggered by lifting a light grocery bag, when she noticed a sharp sudden pain and “pop.” The third rupture occurred spontaneously with a snapping sound the night before surgery.

 The patient had observed some prominence on the ulnar side of her right wrist since childhood but had never experienced any pain or functional disability. There was neither history of trauma, inflammatory disease, diabetes mellitus, or infection, nor positive family history of similar wrist deformity.

The physical examination showed a dorsally subluxated distal radioulnar joint, prominent ulnar styloid, and mild ulnar and volar deviation of the wrist along with limitation of wrist dorsiflexion. Complete loss of active extension of the 3 ulnar fingers was demonstrated, while neurovascular status and all other hand evaluations were normal. The wrist radiographs confirmed the typical findings of Madelung deformity (Figure 1).

Repair of the ruptured tendons and resection of the prominent distal ulna (Darrach procedure) was planned. (Given the patient’s age and evidence of degenerative changes in the radiocarpal joint, correction of the Madelung deformity did not seem necessary). At time of surgery, the recently ruptured third finger extensor tendon was easily found and approximated, and end-to-end repair was performed. The fourth and fifth fingers, however, had to be fished out more proximally from dense granulation tissue. After the distal ulna was resected for a distance of 1.5 cm, meticulous repair of the ulnar collateral ligament and the capsule and periosteum over the end of the ulna was performed. Then, for grafting of the ruptured tendons, the extensor indicis proprius tendon was isolated and transected at the second metacarpophalangeal joint level. A piece of this tendon was used as interpositional graft for the fourth extensor tendon, and the main tendon unit was transferred to the fifth finger extensor. The extensor digiti quinti tendon, which was about to rupture, was further reinforced by suturing it side to side to the muscle and tendon of the extensor indicis proprius (Figure 2).

Postoperatively, the wrist was kept in extension in a cast for 3 weeks while the fingers were free for active movement. A removable wrist splint was used for an additional month. At 3-month follow-up, the patient had regained full and strong finger extension and wrist motion.

At 3-year follow-up, the patient was pain-free, and had full extension of all fingers, full forearm rotation, and near-normal motion (better than her preoperative motion). The grip power on the operated right hand was 215 N, and pinch power was 93 N. (The values for the left side were 254 N and 83 N, respectively, using the Jamar hydraulic hand dynamometer [Patterson Medical].) The patient has had no additional tendon rupture (Figure 3).

Discussion

Madelung deformity was first described by Madelung in 1878 and several cases have reported this deformity. However, extensor tendon rupture caused by Madelung deformity is very rare, reported in few cases.¹

Extensor tendon rupture caused by chronic Madelung deformity has been reported few times in the English literature. Goodwin¹ apparently published the first report of such an occurrence in 1979. Ducloyer and colleagues² from France reported 6 cases of extensor tendon rupture as a result of inferior distal radioulnar joint deformity of Madelung. Jebson and colleagues³ reported bilateral spontaneous extensor tendon ruptures in Madelung deformity in 1992.

The mechanism of tendon rupture seems to be mechanical, resulting from continuous rubbing and erosion of tendons over the deformed ulnar head, which has a rough irregular surface⁴ and leads to fraying of the tendons and eventual rupture and retraction of the severed tendon ends. This rupture usually progresses stepwise from more medial to the lateral tendons.² Older patients are, therefore, subject to chronic repetitive attritional trauma leading to tendon rupture.

Tendons may rupture as a result of a variety of conditions, such as chronic synovitis in rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disease, or crystal deposition in gout.^5-8 Some other metabolic or endocrine conditions that involve tendon ruptures include diabetes mellitus, chronic renal failure, and hyperparathyroidism. Steroid injection into the tendons also has a detrimental effect on tendon integrity and may cause tendon tear.⁹ Mechanical factors, such as erosion on bony prominences, are well-known etiologies for tendon rupture, as commonly seen in rheumatoid arthritis, and have been reported in Kienböck disease,¹⁰ thumb carpometacarpal arthritis,¹¹ Colles fracture, scaphoid fracture nonunion,¹² and Madelung deformity.

Conclusion

Our case reflects the usual middle-aged female presentation of such a tendon rupture. The tendon ruptures were spontaneous in the reported order of ulnar to radial, beginning with the little and ring fingers, and progressed radially. The patient had isolated Madelung deformity with no other sign of dyschondrosteosis¹³ or dwarfism, conditions commonly mentioned in association with Madelung deformity. This case report should raise awareness about possible tendon rupture in any chronic case of Madelung deformity.

Extensor tendon rupture in chronic Madelung deformity, as a result of tendon attrition on the dislocated distal ulna, occurs infrequently. However, it is often seen in patients with rheumatoid arthritis. This issue has been reported in only a few English-language case reports. Here we report a case of multiple tendon ruptures in a previously undiagnosed Madelung deformity. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 56-year-old active woman presented with 50 days’ inability to extend the fourth and fifth fingers of her dominant right hand. The loss of finger extension progressed, over several weeks, to involve the third finger as well. The first 2 tendon ruptures had been triggered by lifting a light grocery bag, when she noticed a sharp sudden pain and “pop.” The third rupture occurred spontaneously with a snapping sound the night before surgery.

 The patient had observed some prominence on the ulnar side of her right wrist since childhood but had never experienced any pain or functional disability. There was neither history of trauma, inflammatory disease, diabetes mellitus, or infection, nor positive family history of similar wrist deformity.

The physical examination showed a dorsally subluxated distal radioulnar joint, prominent ulnar styloid, and mild ulnar and volar deviation of the wrist along with limitation of wrist dorsiflexion. Complete loss of active extension of the 3 ulnar fingers was demonstrated, while neurovascular status and all other hand evaluations were normal. The wrist radiographs confirmed the typical findings of Madelung deformity (Figure 1).

Repair of the ruptured tendons and resection of the prominent distal ulna (Darrach procedure) was planned. (Given the patient’s age and evidence of degenerative changes in the radiocarpal joint, correction of the Madelung deformity did not seem necessary). At time of surgery, the recently ruptured third finger extensor tendon was easily found and approximated, and end-to-end repair was performed. The fourth and fifth fingers, however, had to be fished out more proximally from dense granulation tissue. After the distal ulna was resected for a distance of 1.5 cm, meticulous repair of the ulnar collateral ligament and the capsule and periosteum over the end of the ulna was performed. Then, for grafting of the ruptured tendons, the extensor indicis proprius tendon was isolated and transected at the second metacarpophalangeal joint level. A piece of this tendon was used as interpositional graft for the fourth extensor tendon, and the main tendon unit was transferred to the fifth finger extensor. The extensor digiti quinti tendon, which was about to rupture, was further reinforced by suturing it side to side to the muscle and tendon of the extensor indicis proprius (Figure 2).

Postoperatively, the wrist was kept in extension in a cast for 3 weeks while the fingers were free for active movement. A removable wrist splint was used for an additional month. At 3-month follow-up, the patient had regained full and strong finger extension and wrist motion.

At 3-year follow-up, the patient was pain-free, and had full extension of all fingers, full forearm rotation, and near-normal motion (better than her preoperative motion). The grip power on the operated right hand was 215 N, and pinch power was 93 N. (The values for the left side were 254 N and 83 N, respectively, using the Jamar hydraulic hand dynamometer [Patterson Medical].) The patient has had no additional tendon rupture (Figure 3).

Discussion

Madelung deformity was first described by Madelung in 1878 and several cases have reported this deformity. However, extensor tendon rupture caused by Madelung deformity is very rare, reported in few cases.¹

Extensor tendon rupture caused by chronic Madelung deformity has been reported few times in the English literature. Goodwin¹ apparently published the first report of such an occurrence in 1979. Ducloyer and colleagues² from France reported 6 cases of extensor tendon rupture as a result of inferior distal radioulnar joint deformity of Madelung. Jebson and colleagues³ reported bilateral spontaneous extensor tendon ruptures in Madelung deformity in 1992.

The mechanism of tendon rupture seems to be mechanical, resulting from continuous rubbing and erosion of tendons over the deformed ulnar head, which has a rough irregular surface⁴ and leads to fraying of the tendons and eventual rupture and retraction of the severed tendon ends. This rupture usually progresses stepwise from more medial to the lateral tendons.² Older patients are, therefore, subject to chronic repetitive attritional trauma leading to tendon rupture.

Tendons may rupture as a result of a variety of conditions, such as chronic synovitis in rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disease, or crystal deposition in gout.^5-8 Some other metabolic or endocrine conditions that involve tendon ruptures include diabetes mellitus, chronic renal failure, and hyperparathyroidism. Steroid injection into the tendons also has a detrimental effect on tendon integrity and may cause tendon tear.⁹ Mechanical factors, such as erosion on bony prominences, are well-known etiologies for tendon rupture, as commonly seen in rheumatoid arthritis, and have been reported in Kienböck disease,¹⁰ thumb carpometacarpal arthritis,¹¹ Colles fracture, scaphoid fracture nonunion,¹² and Madelung deformity.

Conclusion

Our case reflects the usual middle-aged female presentation of such a tendon rupture. The tendon ruptures were spontaneous in the reported order of ulnar to radial, beginning with the little and ring fingers, and progressed radially. The patient had isolated Madelung deformity with no other sign of dyschondrosteosis¹³ or dwarfism, conditions commonly mentioned in association with Madelung deformity. This case report should raise awareness about possible tendon rupture in any chronic case of Madelung deformity.

A few days after an incidental cat bite, a patient presented to the emergency department for treatment of poison sumac exposure. He was discharged with oral methylprednisolone for the dermatitis and returned 1 week later with symptoms, examination findings, and laboratory results consistent with sepsis and bilateral upper extremity necrotizing soft-tissue infections. After administering multiple irrigation and débridement procedures, hyperbaric oxygen treatments, and an antibiotic regimen, the patient’s status greatly improved. However, the patient returned 1 month later with a new sternoclavicular joint prominence that was associated with painful crepitus. Additionally, he noted that his wrists were gradually becoming more swollen and painful. Imaging studies showed a lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint bilaterally, consistent with osteomyelitis. The patient was treated with ertapenem for 6 weeks, and his polyarthropathy resolved. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 73-year-old, right-hand–dominant man with no notable medical history presented to the emergency department for treatment of poison sumac exposure, incidentally, a few days after being bitten by a cat on the bilateral distal upper extremities. He was prescribed a course of oral methylprednisolone for dermatitis. A week later, the patient returned to the emergency department with altered mental status, fevers, diaphoresis, lethargy, and polyarthralgia. At the time of presentation, the patient’s vital signs were labile, and he was found to have extensive bilateral upper extremity erythema, blistering, petechiae, purpuric lesions, and exquisite pain with passive range of motion of his fingers and wrists. His leukocyte count was 25.1 × 10⁹/L, and he had elevated C-reactive protein level and erythrocyte sedimentation rate of 150 mg/L and 120 mm/h, respectively. He was admitted for management of sepsis and presumed bilateral upper extremity necrotizing soft-tissue infection.

Broad-spectrum intravenous (IV) antibiotics (vancomycin, piperacillin, tazobactam) were initiated after blood cultures were obtained, and the patient was taken emergently to the operating theatre for irrigation and débridement of his hands and wrists bilaterally. Arthrotomy of the wrist and débridement of the distal extensor compartment and its tenosynovium were performed on the right forearm, in addition to a decompressive fasciotomy of the left forearm. Postoperatively, the patient’s mental status improved and his vital signs gradually normalized. He received multiple hyperbaric oxygen treatments and underwent several additional operative débridement procedures with eventual closure of his wounds. At initial presentation, the differential diagnosis for the severe soft-tissue infection included necrotizing fasciitis or myositis caused by any of a variety of bacterial pathogens. Most notably, it was important to elicit the history of a cat bite to include and consider Pasteurella multocida as a potential pathogen. Initial cultures supported the diagnosis of acute P multocida necrotizing skin and soft-tissue infection, in addition to septic arthritis. The patient’s blood and intraoperative wound cultures grew P multocida. The antibiotic treatment was tailored initially to ampicillin and sulbactam and then to a final regimen of orally administered ciprofloxacin (750 mg twice a day), once susceptibility testing was performed on the cultures. On hospital day 10, the patient was discharged home, receiving a 6-week course of ciprofloxacin to complete the 8-week course of treatment.

At follow-up, approximately 1 month after discharge, the patient noted that he had developed a new right sternoclavicular joint prominence that was associated with painful crepitus. He also noted that his wrists were gradually becoming more swollen and painful bilaterally. Computed tomography scans of the chest were obtained to evaluate the sternoclavicular joint (Figure 1). Repeat radiographs of the wrists were also obtained (Figure 2). Imaging showed lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint, consistent with osteomyelitis. The C-reactive protein level and erythrocyte sedimentation rate at this time were 34 mg/L and 124 mm/h, respectively.

The patient returned to the operating room for débridement and biopsy of the right sternoclavicular joint and left wrist. This patient’s delayed presentation was characterized by a subacute worsening of isolated musculoskeletal complaints. The differential diagnosis then included infection with the same bacterial pathogen versus reactive or inflammatory arthritis. Several intraoperative cultures failed to grow any bacteria, including P multocida, although P multocida was the presumptive cause of the erosive polyarthropathy, considering that symptoms eventually resolved with a repeated course of IV-administered ertapenem for 6 weeks. The patient experienced complete resolution of his joint pain and swelling. He was able to resume his activities of daily living and had no further recurrence of symptoms at follow-up 3 months later.

Discussion

Cat bites often are the source of Pasteurella species infections because the bacteria are carried by more than 90% of cats.¹ These types of infections can cause septic arthritis, osteomyelitis, and deep subcutaneous and myofascial infections because of the sharp and narrow morphology of cat teeth. The infections can progress to necrotizing fasciitis and myositis if not recognized early, as was the case with our patient. Prophylactic antibiotic administration for animal bites is controversial and is not a universal practice.^1,2Pasteurella bacteremia is an atypical progression that occurs more often in patients with pneumonia, septic arthritis, or meningitis. Cases of Pasteurella sepsis, necrotizing fasciitis, and septic arthritis have been reported.^3-7 However, associated progressive septic arthritis and osteomyelitis, despite initial clinical improvement, have not been reported. Severe infection (ie, sepsis and septic shock) can occur in infants, pregnant women, and other immunocompromised patients.⁷ Immune suppression of our patient with steroid medication for poison sumac dermatitis likely contributed to the progression and systemic spread of an initially benign cat bite. Before prescribing steroids, it is imperative to ask about exposures and encourage patients to seek prompt medical attention with worsening or new symptoms. Healthy individuals rarely develop bacteremia; however, in these cases, mortality remains high at approximately 25%.^4,6

The clinical course of this case emphasizes the need for vigilance and thoroughness in obtaining histories from patients presenting with seemingly benign complaints, especially in vulnerable populations, such as infants, pregnant women, and immunocompromised adults. In this case, the progression of symptoms might have been avoided if the patient’s dermatitis had been treated conservatively or with topical rather than systemic steroids.

A few days after an incidental cat bite, a patient presented to the emergency department for treatment of poison sumac exposure. He was discharged with oral methylprednisolone for the dermatitis and returned 1 week later with symptoms, examination findings, and laboratory results consistent with sepsis and bilateral upper extremity necrotizing soft-tissue infections. After administering multiple irrigation and débridement procedures, hyperbaric oxygen treatments, and an antibiotic regimen, the patient’s status greatly improved. However, the patient returned 1 month later with a new sternoclavicular joint prominence that was associated with painful crepitus. Additionally, he noted that his wrists were gradually becoming more swollen and painful. Imaging studies showed a lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint bilaterally, consistent with osteomyelitis. The patient was treated with ertapenem for 6 weeks, and his polyarthropathy resolved. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 73-year-old, right-hand–dominant man with no notable medical history presented to the emergency department for treatment of poison sumac exposure, incidentally, a few days after being bitten by a cat on the bilateral distal upper extremities. He was prescribed a course of oral methylprednisolone for dermatitis. A week later, the patient returned to the emergency department with altered mental status, fevers, diaphoresis, lethargy, and polyarthralgia. At the time of presentation, the patient’s vital signs were labile, and he was found to have extensive bilateral upper extremity erythema, blistering, petechiae, purpuric lesions, and exquisite pain with passive range of motion of his fingers and wrists. His leukocyte count was 25.1 × 10⁹/L, and he had elevated C-reactive protein level and erythrocyte sedimentation rate of 150 mg/L and 120 mm/h, respectively. He was admitted for management of sepsis and presumed bilateral upper extremity necrotizing soft-tissue infection.

Broad-spectrum intravenous (IV) antibiotics (vancomycin, piperacillin, tazobactam) were initiated after blood cultures were obtained, and the patient was taken emergently to the operating theatre for irrigation and débridement of his hands and wrists bilaterally. Arthrotomy of the wrist and débridement of the distal extensor compartment and its tenosynovium were performed on the right forearm, in addition to a decompressive fasciotomy of the left forearm. Postoperatively, the patient’s mental status improved and his vital signs gradually normalized. He received multiple hyperbaric oxygen treatments and underwent several additional operative débridement procedures with eventual closure of his wounds. At initial presentation, the differential diagnosis for the severe soft-tissue infection included necrotizing fasciitis or myositis caused by any of a variety of bacterial pathogens. Most notably, it was important to elicit the history of a cat bite to include and consider Pasteurella multocida as a potential pathogen. Initial cultures supported the diagnosis of acute P multocida necrotizing skin and soft-tissue infection, in addition to septic arthritis. The patient’s blood and intraoperative wound cultures grew P multocida. The antibiotic treatment was tailored initially to ampicillin and sulbactam and then to a final regimen of orally administered ciprofloxacin (750 mg twice a day), once susceptibility testing was performed on the cultures. On hospital day 10, the patient was discharged home, receiving a 6-week course of ciprofloxacin to complete the 8-week course of treatment.

At follow-up, approximately 1 month after discharge, the patient noted that he had developed a new right sternoclavicular joint prominence that was associated with painful crepitus. He also noted that his wrists were gradually becoming more swollen and painful bilaterally. Computed tomography scans of the chest were obtained to evaluate the sternoclavicular joint (Figure 1). Repeat radiographs of the wrists were also obtained (Figure 2). Imaging showed lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint, consistent with osteomyelitis. The C-reactive protein level and erythrocyte sedimentation rate at this time were 34 mg/L and 124 mm/h, respectively.

The patient returned to the operating room for débridement and biopsy of the right sternoclavicular joint and left wrist. This patient’s delayed presentation was characterized by a subacute worsening of isolated musculoskeletal complaints. The differential diagnosis then included infection with the same bacterial pathogen versus reactive or inflammatory arthritis. Several intraoperative cultures failed to grow any bacteria, including P multocida, although P multocida was the presumptive cause of the erosive polyarthropathy, considering that symptoms eventually resolved with a repeated course of IV-administered ertapenem for 6 weeks. The patient experienced complete resolution of his joint pain and swelling. He was able to resume his activities of daily living and had no further recurrence of symptoms at follow-up 3 months later.

Discussion

Cat bites often are the source of Pasteurella species infections because the bacteria are carried by more than 90% of cats.¹ These types of infections can cause septic arthritis, osteomyelitis, and deep subcutaneous and myofascial infections because of the sharp and narrow morphology of cat teeth. The infections can progress to necrotizing fasciitis and myositis if not recognized early, as was the case with our patient. Prophylactic antibiotic administration for animal bites is controversial and is not a universal practice.^1,2Pasteurella bacteremia is an atypical progression that occurs more often in patients with pneumonia, septic arthritis, or meningitis. Cases of Pasteurella sepsis, necrotizing fasciitis, and septic arthritis have been reported.^3-7 However, associated progressive septic arthritis and osteomyelitis, despite initial clinical improvement, have not been reported. Severe infection (ie, sepsis and septic shock) can occur in infants, pregnant women, and other immunocompromised patients.⁷ Immune suppression of our patient with steroid medication for poison sumac dermatitis likely contributed to the progression and systemic spread of an initially benign cat bite. Before prescribing steroids, it is imperative to ask about exposures and encourage patients to seek prompt medical attention with worsening or new symptoms. Healthy individuals rarely develop bacteremia; however, in these cases, mortality remains high at approximately 25%.^4,6

The clinical course of this case emphasizes the need for vigilance and thoroughness in obtaining histories from patients presenting with seemingly benign complaints, especially in vulnerable populations, such as infants, pregnant women, and immunocompromised adults. In this case, the progression of symptoms might have been avoided if the patient’s dermatitis had been treated conservatively or with topical rather than systemic steroids.

A few days after an incidental cat bite, a patient presented to the emergency department for treatment of poison sumac exposure. He was discharged with oral methylprednisolone for the dermatitis and returned 1 week later with symptoms, examination findings, and laboratory results consistent with sepsis and bilateral upper extremity necrotizing soft-tissue infections. After administering multiple irrigation and débridement procedures, hyperbaric oxygen treatments, and an antibiotic regimen, the patient’s status greatly improved. However, the patient returned 1 month later with a new sternoclavicular joint prominence that was associated with painful crepitus. Additionally, he noted that his wrists were gradually becoming more swollen and painful. Imaging studies showed a lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint bilaterally, consistent with osteomyelitis. The patient was treated with ertapenem for 6 weeks, and his polyarthropathy resolved. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 73-year-old, right-hand–dominant man with no notable medical history presented to the emergency department for treatment of poison sumac exposure, incidentally, a few days after being bitten by a cat on the bilateral distal upper extremities. He was prescribed a course of oral methylprednisolone for dermatitis. A week later, the patient returned to the emergency department with altered mental status, fevers, diaphoresis, lethargy, and polyarthralgia. At the time of presentation, the patient’s vital signs were labile, and he was found to have extensive bilateral upper extremity erythema, blistering, petechiae, purpuric lesions, and exquisite pain with passive range of motion of his fingers and wrists. His leukocyte count was 25.1 × 10⁹/L, and he had elevated C-reactive protein level and erythrocyte sedimentation rate of 150 mg/L and 120 mm/h, respectively. He was admitted for management of sepsis and presumed bilateral upper extremity necrotizing soft-tissue infection.

Broad-spectrum intravenous (IV) antibiotics (vancomycin, piperacillin, tazobactam) were initiated after blood cultures were obtained, and the patient was taken emergently to the operating theatre for irrigation and débridement of his hands and wrists bilaterally. Arthrotomy of the wrist and débridement of the distal extensor compartment and its tenosynovium were performed on the right forearm, in addition to a decompressive fasciotomy of the left forearm. Postoperatively, the patient’s mental status improved and his vital signs gradually normalized. He received multiple hyperbaric oxygen treatments and underwent several additional operative débridement procedures with eventual closure of his wounds. At initial presentation, the differential diagnosis for the severe soft-tissue infection included necrotizing fasciitis or myositis caused by any of a variety of bacterial pathogens. Most notably, it was important to elicit the history of a cat bite to include and consider Pasteurella multocida as a potential pathogen. Initial cultures supported the diagnosis of acute P multocida necrotizing skin and soft-tissue infection, in addition to septic arthritis. The patient’s blood and intraoperative wound cultures grew P multocida. The antibiotic treatment was tailored initially to ampicillin and sulbactam and then to a final regimen of orally administered ciprofloxacin (750 mg twice a day), once susceptibility testing was performed on the cultures. On hospital day 10, the patient was discharged home, receiving a 6-week course of ciprofloxacin to complete the 8-week course of treatment.

At follow-up, approximately 1 month after discharge, the patient noted that he had developed a new right sternoclavicular joint prominence that was associated with painful crepitus. He also noted that his wrists were gradually becoming more swollen and painful bilaterally. Computed tomography scans of the chest were obtained to evaluate the sternoclavicular joint (Figure 1). Repeat radiographs of the wrists were also obtained (Figure 2). Imaging showed lytic destruction of the sternoclavicular joint and erosive changes throughout the carpus and radiocarpal joint, consistent with osteomyelitis. The C-reactive protein level and erythrocyte sedimentation rate at this time were 34 mg/L and 124 mm/h, respectively.

The patient returned to the operating room for débridement and biopsy of the right sternoclavicular joint and left wrist. This patient’s delayed presentation was characterized by a subacute worsening of isolated musculoskeletal complaints. The differential diagnosis then included infection with the same bacterial pathogen versus reactive or inflammatory arthritis. Several intraoperative cultures failed to grow any bacteria, including P multocida, although P multocida was the presumptive cause of the erosive polyarthropathy, considering that symptoms eventually resolved with a repeated course of IV-administered ertapenem for 6 weeks. The patient experienced complete resolution of his joint pain and swelling. He was able to resume his activities of daily living and had no further recurrence of symptoms at follow-up 3 months later.

Discussion

Cat bites often are the source of Pasteurella species infections because the bacteria are carried by more than 90% of cats.¹ These types of infections can cause septic arthritis, osteomyelitis, and deep subcutaneous and myofascial infections because of the sharp and narrow morphology of cat teeth. The infections can progress to necrotizing fasciitis and myositis if not recognized early, as was the case with our patient. Prophylactic antibiotic administration for animal bites is controversial and is not a universal practice.^1,2Pasteurella bacteremia is an atypical progression that occurs more often in patients with pneumonia, septic arthritis, or meningitis. Cases of Pasteurella sepsis, necrotizing fasciitis, and septic arthritis have been reported.^3-7 However, associated progressive septic arthritis and osteomyelitis, despite initial clinical improvement, have not been reported. Severe infection (ie, sepsis and septic shock) can occur in infants, pregnant women, and other immunocompromised patients.⁷ Immune suppression of our patient with steroid medication for poison sumac dermatitis likely contributed to the progression and systemic spread of an initially benign cat bite. Before prescribing steroids, it is imperative to ask about exposures and encourage patients to seek prompt medical attention with worsening or new symptoms. Healthy individuals rarely develop bacteremia; however, in these cases, mortality remains high at approximately 25%.^4,6

The clinical course of this case emphasizes the need for vigilance and thoroughness in obtaining histories from patients presenting with seemingly benign complaints, especially in vulnerable populations, such as infants, pregnant women, and immunocompromised adults. In this case, the progression of symptoms might have been avoided if the patient’s dermatitis had been treated conservatively or with topical rather than systemic steroids.

According to the literature, the rate of deep venous thrombosis after total hip arthroplasty (THA) can be high (45%-63%) without prophylactic anticoagulation.^1-6 A meta-analysis of 13 studies found a rate of 51%.⁷ As lower extremity deep venous thrombi are the initial source of symptomatic pulmonary emboli in about 90% of cases,⁸ THA patients are usually given medication postoperatively focused on prevention of these thromboembolic events.⁹ Chemoprophylaxis may involve warfarin, enoxaparin, or their combination in an anticoagulation bridge. Enoxaparin is one of many low-molecular-weight heparins (LMWHs). All LMWHs exert their anticoagulant effect by binding to antithrombin III.¹⁰ The binding of LMWH to antithrombin III catalyzes the inhibition of factor Xa by antithrombin III, disrupting clot formation.¹¹

In its hydroquinone form, vitamin K is essential as a cofactor for carboxylation of the glutamic acid residues of the amino-terminals of the coagulation proteins II, VII, IX, and X, leading to their activation. Anticoagulation by warfarin is achieved by the inhibition of the reductase enzymes that produce vitamin K hydroquinone in the liver from vitamin K epoxide.¹² This inhibition prevents activation of the clotting proteins.^12,13 Prophylaxis with enoxaparin or warfarin can reduce the rate of venous thromboembolic disease to 3.6% and 3.7%, respectively.² However, these medications inhibit the clotting cascade, and their use risks prolonging the healing process.⁹ The delay increases the risk for wound infection,¹⁴ which can lead to a longer hospital stay and therefore higher costs.

We conducted a study to compare patients who received warfarin only with patients who received warfarin bridged with enoxaparin as antithrombotic chemoprophylaxis after THA. Outcomes of interest were number of days until a dry wound was observed and length of hospital stay. We hypothesized that, compared with warfarin-only therapy, bridged therapy would increase the risk for prolonged wound healing and result in longer hospital stays.

Materials and Methods

At our 746-bed academic medical center, 121 THAs were performed between January 1, 2008 and December 31, 2009. This study was approved by the center’s Office for Human Subjects Protections institutional review board (IRB). The research involved collecting or studying existing data, documents, and records recorded anonymously by the investigator in such a manner that subjects could not be identified, directly or through identifiers linked to the subjects, and therefore patient consent was not needed. Therefore, the IRB waived the need for consent. Relevant data included in this study were extracted from patient medical records, given within 35 days of surgery. For each patient, discharge notes provided data on the hospital course, and nurses’ notes provided data on wound status after THA.

Propensity Score Matching

For accurate analysis, it was important to consider confounding factors in both patient groups. Some covariates that may influence accurate analysis are age,¹⁵ diabetes,¹⁶ sex,^15,17 hypertension,¹⁸ and body mass index.^15,19Propensity score, defined as the conditional probability of receiving treatment, given the observed background covariates, was initially defined by Rosenbaum²⁰ and Rubin.²¹ The motivation behind propensity scores can be understood by considering an idealized situation in which the 2 groups are similar on all background characteristics. In nonexperimental studies, researchers aim to find for each treated individual a comparison individual who looks exactly the same as the treated individual with respect to observed pretreatment covariates. Thus, assuming no hidden bias, any difference in outcomes within these pairs can be attributed to the variable of interest and not to any other differences between the treated and comparison individuals. Our study is a typical nonexperimental retrospective study in which the 2 groups being compared are patients receiving warfarin only or warfarin bridged with enoxaparin. To minimize the influence of background covariates, we used matching procedures and present our results both with and without the use of matching techniques.

Data and Results

There are different matching algorithms aimed at matching groups. In our study, the optimal matching procedure alone could not produce adequately matched data, so we used both optimal matching²⁰ and genetic matching.^22,23 Genetic matching procedure with replacement²² can produce well-matched data—it matched each patient in the warfarin-only group with a patient in the bridged-therapy group and allowed different patients to be matched with 1 similar patient in the control group. However, as the same patients in the bridged-therapy group might be matched multiple times, it would complicate the after-matching analysis. We therefore used a 2-step matching procedure to obtain well-matched data, and a simplified analysis procedure after matching. In the first step, we implemented genetic matching with replacement, as introduced by Abadie and Imbens,²² to match each warfarin-only patient with 1 bridged-therapy patient. In the second step, we applied optimal matching to the 2 groups. This 2-step matching turned out to produce better matched pairs, as denoted by Rubin.²¹ Both matching steps were implemented using the MatchIt function in R.²⁴

The balance of matching is checked using criteria suggested by Rubin²¹: (1) standardized difference of means of propensity score, (2) ratio of variances in propensity score in treated and control groups, and (3) for each covariate, ratio of variance in residuals orthogonal to propensity score in treated and control groups.

Table 1 lists the means of the background covariates for each group before and after matching. Table 2 lists the balance check results suggested by Rubin.²¹ After matching, all standardized differences of means are smaller than 0.25, and the variance ratios are between 0.5 and 2, which are the standards suggested²¹ for regression adjustment to be valid after matching.

After genetic matching, 31 bridged-therapy patients and 57 warfarin-only patients remained. After optimal matching, there were 31 patients in each group. Poisson regressions of datasets before and after matching adjustment were fitted.

Results

Wounds of bridged-therapy patients took longer to heal than wounds of warfarin-only patients both before (odds ratio, 2.16; P < .05) and after matching data (odds ratio, 2.39; P < .05) with respect to confounding factors. In addition, bridged-therapy patients had longer hospital stays both before (odds ratio 1.20; P < .05) and after matching data (odds ratio, 1.27; P < .05) with respect to confounding factors. Figures 1 and 2 are histograms displaying the 2 groups and their outcomes.

Discussion

For patients undergoing THA procedures, several important considerations should be taken into account. Colwell and colleagues² showed that, compared with warfarin, enoxaparin offered a 0.1% higher rate of protection against venous thromboembolic disease after THA. However, patients given enoxaparin may face increased risks.²⁵ Hallevi and colleagues²⁶ demonstrated that, compared with warfarin, enoxaparin bridging increased the risk for serious bleeding in patients with cardioembolic stroke. In our review of the literature, we learned that the benefits of bridge therapy in thromboembolic disease have yet to be investigated in THA.

At our academic hospital, the extra costs associated with bridge therapy can be as much as about $2000²⁷ per day per patient. These costs can go much higher, depending on type of patient and types of resources used. Over the 2-year period covered by our study, the costs of using enoxaparin amounted to about $151,200 ($2000 × 1.2 days per patient). If bridging offers no significant protection against thromboembolic disease, then it would be more cost-effective to use a single anticoagulant, particularly enoxaparin, for high-risk patients.

There are significant risk factors associated with prolonged healing of surgical wounds. Protocols outlining these factors may help reduce costs. In addition, when deciding on the use of aggressive anticoagulation therapy, surgeons must consider the risks for prolonged leakage and infection in addition to the risk for thromboembolic disease. Protocols may aid in this process as well. Our study results showed that, compared with warfarin-only therapy, bridged therapy (enoxaparin and warfarin) was associated with longer hospital stays. Further research should examine whether there are advantages that justify the higher risks of delayed wound healing and subsequent infection. Improving our understanding of risk factors associated with anticoagulation therapy will make orthopedic surgery safer for patients.

According to the literature, the rate of deep venous thrombosis after total hip arthroplasty (THA) can be high (45%-63%) without prophylactic anticoagulation.^1-6 A meta-analysis of 13 studies found a rate of 51%.⁷ As lower extremity deep venous thrombi are the initial source of symptomatic pulmonary emboli in about 90% of cases,⁸ THA patients are usually given medication postoperatively focused on prevention of these thromboembolic events.⁹ Chemoprophylaxis may involve warfarin, enoxaparin, or their combination in an anticoagulation bridge. Enoxaparin is one of many low-molecular-weight heparins (LMWHs). All LMWHs exert their anticoagulant effect by binding to antithrombin III.¹⁰ The binding of LMWH to antithrombin III catalyzes the inhibition of factor Xa by antithrombin III, disrupting clot formation.¹¹

In its hydroquinone form, vitamin K is essential as a cofactor for carboxylation of the glutamic acid residues of the amino-terminals of the coagulation proteins II, VII, IX, and X, leading to their activation. Anticoagulation by warfarin is achieved by the inhibition of the reductase enzymes that produce vitamin K hydroquinone in the liver from vitamin K epoxide.¹² This inhibition prevents activation of the clotting proteins.^12,13 Prophylaxis with enoxaparin or warfarin can reduce the rate of venous thromboembolic disease to 3.6% and 3.7%, respectively.² However, these medications inhibit the clotting cascade, and their use risks prolonging the healing process.⁹ The delay increases the risk for wound infection,¹⁴ which can lead to a longer hospital stay and therefore higher costs.

We conducted a study to compare patients who received warfarin only with patients who received warfarin bridged with enoxaparin as antithrombotic chemoprophylaxis after THA. Outcomes of interest were number of days until a dry wound was observed and length of hospital stay. We hypothesized that, compared with warfarin-only therapy, bridged therapy would increase the risk for prolonged wound healing and result in longer hospital stays.

Materials and Methods

At our 746-bed academic medical center, 121 THAs were performed between January 1, 2008 and December 31, 2009. This study was approved by the center’s Office for Human Subjects Protections institutional review board (IRB). The research involved collecting or studying existing data, documents, and records recorded anonymously by the investigator in such a manner that subjects could not be identified, directly or through identifiers linked to the subjects, and therefore patient consent was not needed. Therefore, the IRB waived the need for consent. Relevant data included in this study were extracted from patient medical records, given within 35 days of surgery. For each patient, discharge notes provided data on the hospital course, and nurses’ notes provided data on wound status after THA.

Propensity Score Matching

For accurate analysis, it was important to consider confounding factors in both patient groups. Some covariates that may influence accurate analysis are age,¹⁵ diabetes,¹⁶ sex,^15,17 hypertension,¹⁸ and body mass index.^15,19Propensity score, defined as the conditional probability of receiving treatment, given the observed background covariates, was initially defined by Rosenbaum²⁰ and Rubin.²¹ The motivation behind propensity scores can be understood by considering an idealized situation in which the 2 groups are similar on all background characteristics. In nonexperimental studies, researchers aim to find for each treated individual a comparison individual who looks exactly the same as the treated individual with respect to observed pretreatment covariates. Thus, assuming no hidden bias, any difference in outcomes within these pairs can be attributed to the variable of interest and not to any other differences between the treated and comparison individuals. Our study is a typical nonexperimental retrospective study in which the 2 groups being compared are patients receiving warfarin only or warfarin bridged with enoxaparin. To minimize the influence of background covariates, we used matching procedures and present our results both with and without the use of matching techniques.

Data and Results

There are different matching algorithms aimed at matching groups. In our study, the optimal matching procedure alone could not produce adequately matched data, so we used both optimal matching²⁰ and genetic matching.^22,23 Genetic matching procedure with replacement²² can produce well-matched data—it matched each patient in the warfarin-only group with a patient in the bridged-therapy group and allowed different patients to be matched with 1 similar patient in the control group. However, as the same patients in the bridged-therapy group might be matched multiple times, it would complicate the after-matching analysis. We therefore used a 2-step matching procedure to obtain well-matched data, and a simplified analysis procedure after matching. In the first step, we implemented genetic matching with replacement, as introduced by Abadie and Imbens,²² to match each warfarin-only patient with 1 bridged-therapy patient. In the second step, we applied optimal matching to the 2 groups. This 2-step matching turned out to produce better matched pairs, as denoted by Rubin.²¹ Both matching steps were implemented using the MatchIt function in R.²⁴

The balance of matching is checked using criteria suggested by Rubin²¹: (1) standardized difference of means of propensity score, (2) ratio of variances in propensity score in treated and control groups, and (3) for each covariate, ratio of variance in residuals orthogonal to propensity score in treated and control groups.

Table 1 lists the means of the background covariates for each group before and after matching. Table 2 lists the balance check results suggested by Rubin.²¹ After matching, all standardized differences of means are smaller than 0.25, and the variance ratios are between 0.5 and 2, which are the standards suggested²¹ for regression adjustment to be valid after matching.

After genetic matching, 31 bridged-therapy patients and 57 warfarin-only patients remained. After optimal matching, there were 31 patients in each group. Poisson regressions of datasets before and after matching adjustment were fitted.

Results

Wounds of bridged-therapy patients took longer to heal than wounds of warfarin-only patients both before (odds ratio, 2.16; P < .05) and after matching data (odds ratio, 2.39; P < .05) with respect to confounding factors. In addition, bridged-therapy patients had longer hospital stays both before (odds ratio 1.20; P < .05) and after matching data (odds ratio, 1.27; P < .05) with respect to confounding factors. Figures 1 and 2 are histograms displaying the 2 groups and their outcomes.

Discussion

For patients undergoing THA procedures, several important considerations should be taken into account. Colwell and colleagues² showed that, compared with warfarin, enoxaparin offered a 0.1% higher rate of protection against venous thromboembolic disease after THA. However, patients given enoxaparin may face increased risks.²⁵ Hallevi and colleagues²⁶ demonstrated that, compared with warfarin, enoxaparin bridging increased the risk for serious bleeding in patients with cardioembolic stroke. In our review of the literature, we learned that the benefits of bridge therapy in thromboembolic disease have yet to be investigated in THA.

At our academic hospital, the extra costs associated with bridge therapy can be as much as about $2000²⁷ per day per patient. These costs can go much higher, depending on type of patient and types of resources used. Over the 2-year period covered by our study, the costs of using enoxaparin amounted to about $151,200 ($2000 × 1.2 days per patient). If bridging offers no significant protection against thromboembolic disease, then it would be more cost-effective to use a single anticoagulant, particularly enoxaparin, for high-risk patients.

There are significant risk factors associated with prolonged healing of surgical wounds. Protocols outlining these factors may help reduce costs. In addition, when deciding on the use of aggressive anticoagulation therapy, surgeons must consider the risks for prolonged leakage and infection in addition to the risk for thromboembolic disease. Protocols may aid in this process as well. Our study results showed that, compared with warfarin-only therapy, bridged therapy (enoxaparin and warfarin) was associated with longer hospital stays. Further research should examine whether there are advantages that justify the higher risks of delayed wound healing and subsequent infection. Improving our understanding of risk factors associated with anticoagulation therapy will make orthopedic surgery safer for patients.

According to the literature, the rate of deep venous thrombosis after total hip arthroplasty (THA) can be high (45%-63%) without prophylactic anticoagulation.^1-6 A meta-analysis of 13 studies found a rate of 51%.⁷ As lower extremity deep venous thrombi are the initial source of symptomatic pulmonary emboli in about 90% of cases,⁸ THA patients are usually given medication postoperatively focused on prevention of these thromboembolic events.⁹ Chemoprophylaxis may involve warfarin, enoxaparin, or their combination in an anticoagulation bridge. Enoxaparin is one of many low-molecular-weight heparins (LMWHs). All LMWHs exert their anticoagulant effect by binding to antithrombin III.¹⁰ The binding of LMWH to antithrombin III catalyzes the inhibition of factor Xa by antithrombin III, disrupting clot formation.¹¹

In its hydroquinone form, vitamin K is essential as a cofactor for carboxylation of the glutamic acid residues of the amino-terminals of the coagulation proteins II, VII, IX, and X, leading to their activation. Anticoagulation by warfarin is achieved by the inhibition of the reductase enzymes that produce vitamin K hydroquinone in the liver from vitamin K epoxide.¹² This inhibition prevents activation of the clotting proteins.^12,13 Prophylaxis with enoxaparin or warfarin can reduce the rate of venous thromboembolic disease to 3.6% and 3.7%, respectively.² However, these medications inhibit the clotting cascade, and their use risks prolonging the healing process.⁹ The delay increases the risk for wound infection,¹⁴ which can lead to a longer hospital stay and therefore higher costs.

We conducted a study to compare patients who received warfarin only with patients who received warfarin bridged with enoxaparin as antithrombotic chemoprophylaxis after THA. Outcomes of interest were number of days until a dry wound was observed and length of hospital stay. We hypothesized that, compared with warfarin-only therapy, bridged therapy would increase the risk for prolonged wound healing and result in longer hospital stays.

Materials and Methods

At our 746-bed academic medical center, 121 THAs were performed between January 1, 2008 and December 31, 2009. This study was approved by the center’s Office for Human Subjects Protections institutional review board (IRB). The research involved collecting or studying existing data, documents, and records recorded anonymously by the investigator in such a manner that subjects could not be identified, directly or through identifiers linked to the subjects, and therefore patient consent was not needed. Therefore, the IRB waived the need for consent. Relevant data included in this study were extracted from patient medical records, given within 35 days of surgery. For each patient, discharge notes provided data on the hospital course, and nurses’ notes provided data on wound status after THA.

Propensity Score Matching

For accurate analysis, it was important to consider confounding factors in both patient groups. Some covariates that may influence accurate analysis are age,¹⁵ diabetes,¹⁶ sex,^15,17 hypertension,¹⁸ and body mass index.^15,19Propensity score, defined as the conditional probability of receiving treatment, given the observed background covariates, was initially defined by Rosenbaum²⁰ and Rubin.²¹ The motivation behind propensity scores can be understood by considering an idealized situation in which the 2 groups are similar on all background characteristics. In nonexperimental studies, researchers aim to find for each treated individual a comparison individual who looks exactly the same as the treated individual with respect to observed pretreatment covariates. Thus, assuming no hidden bias, any difference in outcomes within these pairs can be attributed to the variable of interest and not to any other differences between the treated and comparison individuals. Our study is a typical nonexperimental retrospective study in which the 2 groups being compared are patients receiving warfarin only or warfarin bridged with enoxaparin. To minimize the influence of background covariates, we used matching procedures and present our results both with and without the use of matching techniques.

Data and Results

There are different matching algorithms aimed at matching groups. In our study, the optimal matching procedure alone could not produce adequately matched data, so we used both optimal matching²⁰ and genetic matching.^22,23 Genetic matching procedure with replacement²² can produce well-matched data—it matched each patient in the warfarin-only group with a patient in the bridged-therapy group and allowed different patients to be matched with 1 similar patient in the control group. However, as the same patients in the bridged-therapy group might be matched multiple times, it would complicate the after-matching analysis. We therefore used a 2-step matching procedure to obtain well-matched data, and a simplified analysis procedure after matching. In the first step, we implemented genetic matching with replacement, as introduced by Abadie and Imbens,²² to match each warfarin-only patient with 1 bridged-therapy patient. In the second step, we applied optimal matching to the 2 groups. This 2-step matching turned out to produce better matched pairs, as denoted by Rubin.²¹ Both matching steps were implemented using the MatchIt function in R.²⁴

The balance of matching is checked using criteria suggested by Rubin²¹: (1) standardized difference of means of propensity score, (2) ratio of variances in propensity score in treated and control groups, and (3) for each covariate, ratio of variance in residuals orthogonal to propensity score in treated and control groups.

Table 1 lists the means of the background covariates for each group before and after matching. Table 2 lists the balance check results suggested by Rubin.²¹ After matching, all standardized differences of means are smaller than 0.25, and the variance ratios are between 0.5 and 2, which are the standards suggested²¹ for regression adjustment to be valid after matching.

After genetic matching, 31 bridged-therapy patients and 57 warfarin-only patients remained. After optimal matching, there were 31 patients in each group. Poisson regressions of datasets before and after matching adjustment were fitted.

Results

Wounds of bridged-therapy patients took longer to heal than wounds of warfarin-only patients both before (odds ratio, 2.16; P < .05) and after matching data (odds ratio, 2.39; P < .05) with respect to confounding factors. In addition, bridged-therapy patients had longer hospital stays both before (odds ratio 1.20; P < .05) and after matching data (odds ratio, 1.27; P < .05) with respect to confounding factors. Figures 1 and 2 are histograms displaying the 2 groups and their outcomes.

Discussion

For patients undergoing THA procedures, several important considerations should be taken into account. Colwell and colleagues² showed that, compared with warfarin, enoxaparin offered a 0.1% higher rate of protection against venous thromboembolic disease after THA. However, patients given enoxaparin may face increased risks.²⁵ Hallevi and colleagues²⁶ demonstrated that, compared with warfarin, enoxaparin bridging increased the risk for serious bleeding in patients with cardioembolic stroke. In our review of the literature, we learned that the benefits of bridge therapy in thromboembolic disease have yet to be investigated in THA.

At our academic hospital, the extra costs associated with bridge therapy can be as much as about $2000²⁷ per day per patient. These costs can go much higher, depending on type of patient and types of resources used. Over the 2-year period covered by our study, the costs of using enoxaparin amounted to about $151,200 ($2000 × 1.2 days per patient). If bridging offers no significant protection against thromboembolic disease, then it would be more cost-effective to use a single anticoagulant, particularly enoxaparin, for high-risk patients.

There are significant risk factors associated with prolonged healing of surgical wounds. Protocols outlining these factors may help reduce costs. In addition, when deciding on the use of aggressive anticoagulation therapy, surgeons must consider the risks for prolonged leakage and infection in addition to the risk for thromboembolic disease. Protocols may aid in this process as well. Our study results showed that, compared with warfarin-only therapy, bridged therapy (enoxaparin and warfarin) was associated with longer hospital stays. Further research should examine whether there are advantages that justify the higher risks of delayed wound healing and subsequent infection. Improving our understanding of risk factors associated with anticoagulation therapy will make orthopedic surgery safer for patients.