Clinical Outcomes and Complications during the Learning Curve for Reverse Total Shoulder Arthroplasty: An Analysis of the First 40 Cases

BACKGROUND: The purpose of this study was to investigate the results and complications during the learning curve of reverse total shoulder arthroplasty (RTSA) for rotator cuff deficiency. METHODS: We retrospectively reviewed the first 40 cases of RTSA performed by a single surgeon. The mean age of patients was 72.7 years (range, 63 to 81 years) and mean follow-up period was 26.7 months (range, 9 to 57 months). Clinical outcomes were evaluated using a visual analog scale (VAS) for pain, the University of California at Los Angeles (UCLA) shoulder score, American Shoulder and Elbow Surgeon (ASES) score, subjective shoulder value (SSV), and active range of motion (ROM). Intraoperative and postoperative complications were also evaluated. RESULTS: The average VAS pain score, UCLA score, ASES score, and SSV improved from 6.9%, 12.8%, 29.0%, and 29.0% before surgery to 1.6%, 27.0%, 73.3%, and 71.5% after surgery, respectively (p < 0.001). The mean forward flexion, abduction, and external rotation improved from 68.0°, 56.9°, and 28.0° before surgery to 131.0°, 112.3°, and 38.8° after surgery, respectively (p < 0.001, p < 0.001, and p = 0.021). However, the mean internal rotation did not improve after surgery (p = 0.889). Scapular notching was observed in 33 patients (51.5%). Eight shoulders (20%) had complications, including 2 major (1 deep infection and 1 glenoid fixation failure) and 6 minor complications (3 brachial plexus injuries, 2 acromial fractures, and 1 intraoperative periprosthetic fracture). CONCLUSIONS: The first 40 cases of RTSA performed by a single surgeon during the learning curve period showed satisfactory short-term follow-up results with an acceptable complication rate.