Abstract
A 62-year-old man presented with bilateral posterior shoulder dislocations 2 months after sustaining an accidental electric shock while fishing. Imaging confirmed chronic locked posterior dislocations with reverse Hill-Sachs lesions and large humeral head articular defects (approximately 60% on the left and 55% on the right), together with partial-thickness supraspinatus and subscapularis tendon tears. The patient underwent staged reverse total shoulder arthroplasty. At the 12-month follow-up, he was free from pain with a markedly improved active range of motion (forward flexion, 130°; abduction, 100°) and excellent functional outcomes (constant score: 86, left shoulder; 83, right shoulder; ASES, 90). This case supports reverse shoulder arthroplasty as a viable option for a chronic bilateral posterior shoulder dislocation with substantial humeral head defects.