A systematic review of surgical treatment of reverse shoulder arthroplasty associated acromial and scapular spine stress fractures.

Background: Current treatment options for acromial and scapular spine fracture (ASF) after reverse total shoulder arthroplasty (rTSA) include nonoperative immobilization or surgical fixation, but optimal patient selection for each option remains unclear. We performed a descriptive analysis of operative vs. nonoperative treatment to identify patterns in fracture type, functional outcomes, and operative timing. Methods: We reviewed 11 studies reporting nonoperative and operative management of post-rTSA ASFs. Data were extracted based on fracture subtype, union rate, time to surgery, indication for surgery, and functional outcomes. We assessed heterogeneity in study design, baseline reporting, and sample size when making interstudy comparisons. Risk of bias was evaluated in accordance with the Joanna Briggs Institute method. Results: Eleven studies with a total of 88 surgically managed fractures were identified. Across 8 studies reporting union rates, the operative group achieved higher radiographic union (range, 69%-100%) than the nonoperative group (30%-79%), though only one study of acute Levy II/III patterns treated within 6 weeks of fracture demonstrated statistical significance. However, most studies reported that patient-reported outcomes were similar between the groups. In addition, surgical management was associated with a notable complication profile, including hardware failure and the need for secondary procedures. In most studies, surgical treatment was performed for fractures that did not respond to an initial trial of immobilization and persistent pain. Outcome measures varied and were often reported without baseline values. Small operative cohorts across all studies limited statistical power. Conclusion: In the studies included in this review, Levy type III fractures were treated surgically at a higher rate than other fracture types due to poor function and pain. Surgical management of ASFs was largely reserved for patients who failed nonoperative treatment. Improvement of functional outcomes in surgical intervention compared to nonoperative treatment was found only in acute surgical intervention. No statistically significant difference was found when comparing delayed surgical intervention and nonoperative treatment. Surgical management was associated with significantly higher union rates than nonoperative management. However, functional improvements were largely modest and comparable to nonoperative management in delayed cases, and the benefits of surgery must be weighed against a high complication rate. Double plate fixation was the predominant surgical technique for ASF after rTSA. The use of the Levy classification system and assessment of uniform functional outcomes in future studies would allow for stronger analysis of the comparative impacts of surgical and nonoperative treatment of ASF after rTSA.