Stemless reverse shoulder arthroplasty: Clinical and radiological outcomes with minimum two years follow-up.

Abstract

Recently, a stemless reverse shoulder arthroplasty (RSA) design was developed in order to preserve bone stock. Clinical and radiological studies of such design with larger cohorts with over 100 patients are not frequent. The purpose of this study was to present clinical and radiological results of a newly developed stemless RSA. The hypothesis was that this design would provide similar clinical and radiological results compared to other stemless and stemmed implants. Between September 2015 and December 2019, all patients who had a primary EASYTECH® stemless RSA were considered eligible for inclusion in this prospective multi-center study. Minimum follow-up was two years. Clinical outcomes consisted of Constant score, adjusted Constant score, QuickDASH, subjective shoulder value (SSV) and the American Shoulder and Elbow Surgeons Shoulder Score (ASES). Radiographic parameters included radiolucency, loosening, scapular notching and specific geometrical parameters. Stemless RSA was implanted in 115 patients (61 women and 54 men) at 6 different clinical centers. The average age at the time of surgery was 68.7 years. The average preoperative Constant score was 32.5 and it showed significant improvement at the latest follow-up at 61.8 (p < .001). SSV also demonstrated significant improvement postoperatively (27.0 pts to 77.5 pts, p< .001). Scapular notching was observed in 28 patients (24.3%), humeral loosening in 5 patients (4.3%) and glenoid loosening in 4 patients (3.5%). Our total complication rate was 17.4%. Eight patients (4 women and 4 men) underwent an implant revision. Clinical outcomes of this stemless RSA seem to be comparable to other humeral designs, however complication and revision rates are higher than rates compared to historical controls. Surgeons should proceed with caution when using this implant until longer term follow-up data is available.