SAN DIEGO – Point-of-care ultrasound should be the go-to approach for the routine assessment of suspected shoulder dislocations in the ED, based on data from a prospective, multicenter study presented at the annual meeting of the American College of Emergency Physicians.
In the observational study, the average time needed to diagnose shoulder dislocation using ultrasound was 18 seconds, far faster than time from triage to x-ray, according to Michael Secko, MD, director of the emergency ultrasound division at Stony Brook University (NY).
The results from this study, called MUDDS (Musculoskeletal Ultrasound to Diagnose Dislocated Shoulders), support point-of-care ultrasound as a faster and more readily performed alternative to x-ray. Of the 46 adult patients enrolled so far in the ongoing study, ultrasound’s sensitivity has been 96% and its specificity 100% when validated by x-ray findings.
In the study, adults presenting to the ED are evaluated with point-of-care ultrasound from a posterior approach using either a curvilinear or linear transducer in the transverse plane. About half of the patients enrolled so far had injuries caused by falls, and many of the others had a shoulder complaint related to being pulled. Slightly more than one-third had a previous shoulder dislocation.
When evaluated with point-of-care ultrasound and x-ray, 23 of the 42 evaluable patients had a dislocation. The time from triage to ultrasound evaluation averaged 60 minutes, 40 minutes faster than the average of 100 minutes from triage to x-ray. Both tests were ordered at the same time.
Ultrasound performed less well for the diagnosis of a fracture, with a sensitivity of only 53%. Dr. Secko said the anterior approach would not be expected to provide a comprehensive assessment for fracture. He noted, for example, that there was no attempt in this study to evaluate patients for the presence of Bankart lesions. However, in those found to have a fracture on point-of-care ultrasound, the specificity of this imaging tool was 96%.
Ultimately, a major goal of this study was to determine whether a posterior point-of-care ultrasound could provide a quick answer to the question, “is it in or out?” Although patients are still being enrolled, Dr. Secko believed there is already good evidence that ultrasound is fast and effective for diagnosing dislocations.
Others have addressed this same question. Citing a meta-analysis published last year, Dr. Secko reported that all but one of four studies evaluating ultrasound for shoulder dislocations found a sensitivity and specificity of 100% (Gottlieb M et al. West J Emerg Med. 2017 Aug;18:937-942).
Many centers have already switched to ultrasound for the evaluation of shoulder dislocations, according to Andrew S. Liteplo, MD, who moderated the ACEP session in which Dr. Secko presented his data. “If you are not already doing this for suspected shoulder dislocation, start right away because it is easy and awesome,” said Dr. Liteplo, who is chief of the division of ultrasound in emergency medicine at Massachusetts General Hospital, Boston. He also advised that ultrasound can also can be performed after reduction to confirm the efficacy of treatment.
Dr. Secko reported no financial relationships relevant to this study.