Bilateral Anterior Shoulder Dislocation: A Systematic Review

To compile the existing literature on bilateral anterior shoulder dislocation (BASD) and analyze patient demographics, mechanisms of injury, injury characteristics, management, and outcome.

This systematic review was conducted in accordance with Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) guidelines. Online databases, including Ovid Medline 1946-, Embase.com 1947-, Scopus 1960-, Cochrane Central, and Clinicaltrials.gov were systematically queried. Studies eligible for inclusion were case reports or case-series, documenting BASD. Two reviewers independently screened and applied a set of a priori exclusion criteria to each returned study. Data were extracted, compiled, and synthesized from each reported case of BASD. Contingency tables/Chi-Square Analyses, T-tests, and univariate regression analyses were conducted to assess relationships between different variables.

Eighty-one studies (87 cases of BASD) were included. Patients were 41.1 (SD± 19.5) years old and most were male (n=63; 72.4%). Around a quarter of patients (28.7%) had a history of epilepsy/seizures or were being worked-up for such. Younger males were more likely to have BASD due to a seizure or electrocution (P<0.05). Close to a third of cases (n=27; 31.0%) were delayed in presentation. Those sustaining seizures or electrocutions were more likely to be delayed in presentation (P=0.013). Most events resulted in simple dislocations that were closed reduced successfully. BASD resulting from seizures or electrocutions were more likely to be fracture-dislocations (P=0.018); and in younger patients with fracture-dislocations, closed reduction was more often to fail or not be attempted (P<0.05). Median follow-up was 6 months (IQR: 3 months - 12 months). Seven patients (10.6%) had complications and 4 (2.3%) demonstrated recurrent instability.

In young males presenting with BASD without known trauma, suspicion should be high for a convulsant event. In patients with a known seizure disorder who present with chronic bilateral shoulder or arm pain, BASD should be considered and work-up should be expedited to avoid misdiagnosis.