The radiographic and clinical outcomes of stemless reverse total shoulder arthroplasty: a minimum 2-year follow-up study

Background: The purpose of this study was to examine the radiographic and clinical outcomes of stemless reverse total shoulder arthroplasty (RTSA) after a minimum 2-year follow-up.

Methods: Between July 2018 and March 2023, 50 patients underwent 50 stemless RTSA with the Lima component. Twenty-eight patients with a follow-up of more than 2 years were reviewed. The average age was 71.9 years (range, 61-85 years), and the average follow-up period was 2.2 years (range, 2.0-5.1). Bone marrow density of the proximal humerus was measured before RTSA. We evaluated preoperative and postoperative range of motion, clinical score, radiographic change, and postoperative complications.

Results: Significant increases were observed postoperatively in forward flexion (112.0º-162.5º, P<0.01) and internal rotation (from L3 to T12 level; P<0.05). No changes were observed in external rotation (from 43.0º to 45.2º; P=0.762). The clinical scores improved for Korean Shoulder Scoring system (from 64 to 93, P<0.01) and American Shoulder and Elbow Surgeons score (from 17.5 to 27.3, P<0.01). Although radiolucent lines of less than 2 mm were observed in all cases, no osteolysis and loosening of the stemless humeral component was found. In one case, the stemless humeral component pulled out at the 1-week follow-up, and a revision was implemented to replace it with a stemmed humeral component. Scapular notching was observed in 18 cases.

Conclusions: Stemless RTSA showed good radiographic and clinical results after a minimum 2-year follow-up. Level of evidence: IV.