Traumatic Asymmetric Bilateral Shoulder Dislocation: The First Case Report in Mexico

Asymmetric bilateral shoulder dislocation is an exceptionally rare pattern of glenohumeral injury characterized by simultaneous dislocation of both shoulders in different directions. Since its first description in 1985, only a limited number of cases have been reported worldwide. Most cases are associated with seizures or electrical injuries, while traumatic mechanisms are uncommon. Reporting additional cases is important to improve recognition and management of this unusual injury pattern.

We report the case of a 39-year-old Hispanic male who presented to the emergency department after a high-energy motorcycle accident. Clinical examination revealed bilateral shoulder deformity and severe pain with marked limitation of motion, without neurovascular deficit. Radiographic evaluation demonstrated asymmetric bilateral glenohumeral dislocation, consisting of an anterior subglenoid dislocation of the left shoulder and a posterior dislocation of the right shoulder. Computed tomography confirmed a non-engaging reverse Hill-Sachs lesion involving approximately 18% of the articular surface of the right humeral head. Urgent closed reduction under sedation was successfully performed using different reduction maneuvers for each shoulder, achieving stable joint congruency. The patient was managed conservatively with temporary immobilization followed by progressive physical rehabilitation. During follow-up, the patient demonstrated progressive improvement in pain and range of motion. At 6 months, full functional recovery was achieved without recurrence or complications.

This report describes the first documented case in Mexico of traumatic asymmetric bilateral shoulder dislocation caused by a high-energy mechanism without associated fractures. The case highlights the importance of maintaining a high index of suspicion and performing a comprehensive radiological evaluation in patients with shoulder trauma. Early diagnosis and prompt closed reduction followed by appropriate rehabilitation can lead to favorable functional outcomes even in rare and complex injury patterns.