Simultaneous bilateral acromial base fractures after staged reverse total shoulder arthroplasty: A case report

Acromial and scapular spine fractures after reverse total shoulder arthroplasty (RTSA) are a well-known complication that may negatively impact the effects of long-term outcomes. However, to the best of our knowledge, there has been no report of simultaneous bilateral fractures of the acromion or scapular spine that occurred following staged RTSA.

A 79-year-old right-handed male visited our outpatient clinic with a chief complaint of pain and limited motion of both shoulder joints for a one-year duration. Based on plain radiographs and magnetic resonance images, the preoperative diagnosis was bilateral cuff tear arthropathy with failed rotator cuff repair. This patient was treated with staged bilateral RTSA at a two-month interval. At 5 and 3 mo after right and left side surgery, the patient returned to the outpatient clinic with severe pain and limited motion of both shoulder joints for 2 wk without a traumatic event. A computed tomography scan revealed non-displaced acromial base fractures of both shoulders. Considering bilateral involvement, fracture location, and patient's demand, open reduction and internal fixation (ORIF) using plate for bilateral acromial base fractures were performed. At 2 years after ORIF, the fracture was completely healed, and the patient was satisfied with shoulder status.

This report describes an extremely rare case of simultaneous bilateral acromial base fractures after staged RTSA managed successfully by ORIF with a pre-contoured plate designed for distal clavicle fractures. Although acromial fracture after RTSA can be treated conservatively, simultaneous bilateral fractures may warrant surgical intervention as a means of addressing difficulties in activities of daily living.