Acromial Stress Fractures in Reverse Total Shoulder Arthroplasty: Diagnosis, Prevention, and Treatment

PURPOSE OF REVIEW: This review critically evaluates the literature on acromial stress fractures (ASFs) following reverse total shoulder arthroplasty (rTSA), with a focus on risk factors, prevention, and treatment. By synthesizing contemporary evidence and highlighting areas of ongoing debate, this review aims to provide clinicians with an updated understanding of these complications and identify priorities for future research. RECENT FINDINGS: ASFs have an approximate incidence of 3-5% following rTSA. Preoperative risk factors include female sex, acromial morphology, rheumatologic disease, chronic systemic steroid use, and intra-articular steroid use within three months of arthroplasty. Intra-operative risk factors include implant positioning parameters such as excessive distalization, as well as prominence of posterior superior baseplate screws, and resection of the coracoacromial ligament. While nonoperative management is the first line of treatment for many ASFs, displaced fractures are commonly treated operatively. Operative intervention facilitates fracture union but does not consistently improve functional outcomes. Intranasal calcitonin is currently being studied as an adjuvant therapy. The impact of implant design features and placement decisions addressing distalization and lateralization are areas of ongoing study. ASFs remain a challenging complication of rTSA with limited treatment success, highlighting the need for better risk identification, bone health optimization, thoughtful intraoperative decision-making, and evaluation of early interventions to improve prevention and progression.