Aims: Acromial fractures following reverse shoulder arthroplasty (RSA) have a wide range of incidences in reported case series. This study evaluates their incidence following RSA by systematically reviewing the current literature. Materials and Methods: A systematic review using the search terms “reverse shoulder”, “reverse total shoulder”, or “inverted shoulder” was performed using PubMed, Web of Science, and Cochrane databases between 1 January 2010 and 31 March 2018. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. Studies were included if they reported on RSA outcomes and the incidence rate of acromial and/or scapular spine fractures. The rate of these fractures was evaluated for primary RSA, revision RSA, RSA indications, and RSA implant design. Results: The review included 90 articles out of 686 identified after exclusions. The incidence rate of acromial and/or scapular spine fractures was 2.8% (253/9048 RSAs). The fracture rate was similar for primary and revision RSA (2.8% vs 2.1%; p = 0.4). Acromial fractures were most common after RSA for inflammatory arthritis (10.9%) and massive rotator cuff tears (3.8%). The incidence was lowest in RSA for post-traumatic arthritis (2.1%) and acute proximal humerus fractures (0%). Lateralized glenosphere design had a significantly higher rate of acromial fractures compared with medial glenosphere designs. Conclusion: Based on current English literature, acromial and/or scapular spine fractures occur at a rate of 2.8% after RSA. The incidence is slightly more common after primary compared with revision arthroplasty. Also, higher rates of acromial fractures are reported in RSA performed for inflammatory arthritis and in the lateralized glenoid design. Cite this article: Bone Joint J 2019;101-B:627–634.

Background The incidence of humeral shaft fractures has been increasing over time. This represents a growing public health concern in a climate of cost containment. The purpose of this study is to analyze national trends in surgical management of humeral shaft fractures and determine factors predictive of surgical intervention. Materials and methods Humeral shaft fractures were identified by the International Classification of Diseases, Ninth Revision, Clinical Modification codes 812.21 and 812.31 in the United States Nationwide Inpatient Sample from 2002 to 2011. Open reduction and internal fixation (ORIF) was identified by code 79.31 (ORIF, humerus). Other case codes analyzed were 79.01 (closed reduction without internal fixation), 79.11 (closed reduction with internal fixation), and 79.21 (open reduction without internal fixation). Multivariate regression analysis was utilized to determine predictive factors for utilization of ORIF. Results 27,908 humeral shaft fractures were identified. Utilization of ORIF increased from 47.2% of humeral shaft fractures in 2002 to 60.3% in 2011. Demographically, patients who underwent ORIF were younger (51.5 versus 59.7 years, p < 0.001; odds ratio 0.87 per decade of age). There were modest increases in ORIF usage with private insurance, open fracture, and hospital size, which persisted with multivariate regression analysis. Surprisingly, there was a tendency to shift from a slight increase in ORIF for males with the bivariate case to a slight preference for females in the multivariate case. Conclusion Utilization of ORIF for humeral shaft fractures has been steadily increasing with time. Surgical intervention was more common with younger patients, female gender, private insurance, and larger hospital size. The increasing incidence of surgical management for humeral shaft fractures may represent a public health burden given the historical success of non-operative management. Level of evidence IV.

Background: Anatomic total shoulder arthroplasty improves pain and function with a reported reoperation rate of approximately 1% per year. With improved glenoid fixation, reverse shoulder arthroplasty implants may outperform anatomic total shoulder arthroplasty. We evaluate the functional outcomes and reoperation rate of anatomic total shoulder arthroplasty versus reverse shoulder arthroplasty at a minimum eight-year follow-up or revision. Methods: Between 2005 and 2010, 187 shoulders (137 anatomic total shoulder arthroplasty, 50 reverse shoulder arthroplasty) were retrospectively reviewed at a mean of 8.8 years. The mean age at surgery was 67 years. Females were more commonly treated with reverse shoulder arthroplasty. Both groups had similar body mass index and comorbidities. Outcome measures evaluated included abduction, forward elevation, external rotation, internal rotation, Simple Shoulder Test, Constant score, American Shoulder and Elbow Score, University of California Los Angeles Shoulder score, and Shoulder Pain and Disability Index. Results: At follow-up, anatomic total shoulder arthroplasty demonstrated greater overhead range of motion and external rotation. All patient-reported outcomes remained similar between groups. Reverse shoulder arthroplasty patients were more likely to rate shoulders as much better or better after surgery (90% versus 67%, p = 0.004). Complications were observed in 24% of anatomic total shoulder arthroplasties and 8% of reverse shoulder arthroplasties (p = 0.02). Reoperation was more common in anatomic total shoulder arthroplasties (23% versus 4%, p = 0.003). Discussion: At mid-to-long-term follow-up, reverse shoulder arthroplasties demonstrated significantly fewer complications and reoperations than anatomic total shoulder arthroplasties. Despite similar patient-reported outcomes, reverse shoulder arthroplasty patients were more likely to be satisfied with their shoulder.