Bilateral reverse shoulder arthroplasty in a patient with progressive supranuclear palsy: a case report.

Introduction: Progressive supranuclear palsy (PSP) is a rare neurodegenerative disorder characterized by postural instability, oculomotor dysfunction, and progressive motor decline. Surgical management of musculoskeletal disorders in PSP is challenging, and reports of reverse total shoulder arthroplasty (RSA) in this population are scarce. Case presentation: We report a 72-year-old woman with a 5-year history of PSP who developed bilateral shoulder pain and pseudoparalysis due to cuff tear arthropathy. After multidisciplinary discussion, staged bilateral RSA was performed using the Equinoxe® Reverse Shoulder System (Exactech). The right side was prioritized due to greater pain and disability, and rehabilitation was tailored to her neurological condition. At 2.5-year (right) and 2-year (left) follow-up, forward flexion improved from 70° to 120° (right) and from 60° to 110° (left), while external rotation improved from -10°/20° to 20°/20°. Constant scores improved from 22 to 78 (right) and from 24 to 75 (left); Japanese Orthopaedic Association (JOA) scores improved from 38/80 to 72/80 and from 40/80 to 70/80, respectively. Clinical discussion: Despite neuromuscular impairments associated with PSP, the patient achieved meaningful pain relief and functional improvement. The lateralized design of the implant contributed to recovery of forward elevation and external rotation. Conservative management and anatomic arthroplasty were unsuitable due to irreparable cuff tears. No perioperative complications, dislocations, or neurological deterioration were observed. Conclusion: Staged bilateral RSA was safely performed in a patient with PSP and resulted in significant improvements in pain, range of motion, and daily activity. Careful patient selection, implant choice, and neurologically adapted rehabilitation are essential in this complex population.