Ultrasound for the diagnosis of shoulder dislocation and reduction: A systematic review and meta-analysis

Background Shoulder dislocations are a common injury prompting presentation to the emergency department. Point-of-care ultrasound (POCUS) is a diagnostic tool for shoulder dislocations, which has the potential to reduce time to diagnosis and reduction, radiation exposure, and health care costs. This systematic review sought to evaluate the diagnostic accuracy of POCUS for diagnosing shoulder dislocations. Methods We searched PubMed, Scopus, CINAHL, LILACS, the Cochrane databases, Google Scholar, and bibliographies of selected articles for all prospective and randomized controlled trials evaluating the diagnostic accuracy of POCUS for identifying shoulder dislocations. We dual-extracted data into a predefined worksheet and performed quality analysis using the QUADAS-2 tool. We performed a meta-analysis with subgroup analyses by technique and transducer type. As a secondary outcome, we assessed the diagnostic accuracy of identifying associated fractures. Results Ten studies met our inclusion criteria, comprising 1,836 assessments with 636 dislocations (34.6%). Overall, POCUS was 100% (95% confidence interval [CI], 85.6%-100%) sensitive and 100% (95% CI, 79.4%-100%) specific for the diagnosis of shoulder dislocation with a LR+ of 11,254.8 (95% CI, 3.9-3.3e7) and a LR- of <0.1 (95% CI, < 0.1-0.2). When compared with the anterior/lateral technique, the posterior technique had greater sensitivity but no difference in specificity. There was no difference between transducer types. POCUS was also 96.8% (95% CI, 92.6%-98.7%) sensitive and 99.7% (95% CI, 92.5%-100%) specific for the diagnosis of associated fractures. Conclusions POCUS is a sensitive and specific tool for the rapid identification of shoulder dislocations and reductions, as well as for the detection of associated fractures. POCUS should be considered as an alternate diagnostic tool for the diagnosis and management of shoulder dislocations.