Safety and Efficacy of Subscapularis-Sparing Shoulder Arthroplasty Approaches: A Systematic Literature Review

Nonhealing or rupture of the subscapularis after shoulder arthroplasty has been identified as a source of shoulder pain, weakness, and potentially prosthetic instability. Subscapularis-sparing approaches have been developed to mitigate this risk. However, these approaches are rarely used, despite the increasing frequency of shoulder arthroplasty. This review aims to assess the safety and efficacy of subscapularis-sparing approaches for shoulder arthroplasty.

A PRISMA-compliant review of the English literature in the PubMed/MEDLINE database after January 1, 2014, was conducted to identify clinical studies that reported the use of subscapularis-sparing shoulder arthroplasty in adults. Studies included in relevant systematic reviews were also screened. Baseline demographic data, procedural data including procedure time and blood loss, and treatment characteristics including surgical approach and device used were extracted. Efficacy outcomes included range of motion, functional scores, strength, pain, and implant stability or failure. Safety outcomes included infection, severity of infection, and antibiotic use. Because of the low number of comparative studies, study conclusions were qualitatively compared.

A total of 15 studies (1573 patients) reporting subscapularis-sparing shoulder arthroplasty were identified. Eight studies reported reverse arthroplasty (RSA), whereas seven reported anatomic arthroplasty (TSA), including one reporting hemiarthroplasty. Eight studies directly compared subscapularis-sparing and nonsparing techniques. The comparative studies reported that subscapularis-sparing techniques had comparable outcomes to nonsparing techniques in both TSA and RSA, including range of motion, functional scores, pain, and revision. Findings for subscapularis integrity were similar between studies using TSA and RSA.

Subscapularis-sparing shoulder arthroplasty is a safe and effective technique with comparable patient outcomes to nonsparing techniques. The number of comparative studies is limited, and more randomized controlled trials are needed to confirm these results.