Glenosphere Size Does Not Matter in Reverse Total Shoulder Arthroplasty

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Musculoskeletal Research

Background:

• Reverse total shoulder arthroplasty (TSA) is a common procedure for complex shoulder conditions.
• Limited data exists on the impact of glenosphere size on reverse TSA outcomes.
• Understanding glenosphere size influence is crucial for optimizing surgical results.

Purpose of the Study:

• To investigate the effect of glenosphere size (36mm vs. 40mm) on postoperative outcomes after reverse TSA.
• To compare range of motion, patient-reported outcomes, and radiographic variables between different glenosphere sizes.

Main Methods:

• Retrospective analysis of patients undergoing reverse TSA with a minimum 2-year follow-up.
• Patients stratified into 36mm and 40mm glenosphere size cohorts.
• Evaluation of range of motion, ASES, VAS pain, and SST scores; assessment of scapular notching and loosening.

Main Results:

• Significant improvements in range of motion (except internal rotation) observed in both cohorts.
• No significant differences in postoperative range of motion, ASES, or VAS pain scores between 36mm and 40mm groups.
• Forward elevation: 134° (36mm) vs. 133° (40mm); External rotation: 37° (36mm) vs. 35° (40mm).

Conclusions:

• Reverse TSA yields consistent improvements in shoulder function and range of motion regardless of glenosphere size.
• Glenosphere size does not appear to be a critical factor in short-to-mid-term reverse TSA outcomes.
• Further research may explore long-term effects and specific patient subgroups.