Reverse Shoulder Arthroplasty with a Glenoid-Sided Lateralized Prosthesis and Concomitant Latissimus Dorsi Transfer...

Reverse total shoulder arthroplasty (rTSA) using a lateralized implant design is commonly employed to address deficits in external rotation. In select cases, rTSA is combined with a concomitant latissimus dorsi tendon transfer (rTSA+LT) to augment external rotation. This study compared the clinical and radiographic outcomes of patients undergoing rTSA+LT with those undergoing rTSA alone (rTSA-only). We hypothesized that patients who underwent rTSA+LT would demonstrate (1) improved clinical outcomes especially, active external rotation (ER); and (2) a higher incidence of abnormal radiographic findings compared with rTSA-only patients.

Patients with preoperative ER deficit who underwent rTSA+LT were propensity score-matched (PSM) to a cohort treated with rTSA alone. Patients were included if they received an rTSA with lateralized-glenosphere and inlay-stem implant designs for massive irreparable rotator cuff tears without severe glenohumeral arthritis (Hamada 1-4), minimum three months of radiographic and minimum one year of clinical follow-up including American Shoulder and Elbow Surgeons (ASES) score. Of 2,242 patients who underwent rTSA, 196 in the rTSA-only cohort and 26 in the rTSA+LT cohort met inclusion criteria, which resulted in 26 unique, 1:1 PSM pairs.

Mean follow-up was 5 years (range, 1-15 years). Both rTSA+LT and rTSA-only cases demonstrated no differences in the magnitudes of improvement from preoperatively to a minimum 1-year follow-up in final ASES scores (ΔASES score 25.8; 95% confidence interval [CI, 14.2-37.4] vs. 33.7 [22.5-44.9], respectively; P > 0.611) and ER (ΔER; 33° [20°-46°] vs. 36° [28°-45°], respectively; P > 0.635). Results for the minimum 2-year follow-up group also demonstrated no differences between rTSA+LT an rTSA-only cohorts in ΔASES (26.0 [12.5-39.5] vs. 33.4 [19.8- 47.0], respectively; P > 0.719) and ΔER (27° [20°-35°] vs. 35° [27°-43°], respectively; P > 0.498). However, the rTSA+LT cohort demonstrated a higher incidence of early proximal humeral osseous erosion on postoperative imaging (96% [23/24] vs. 4% [1/26]; P <0.001).

In this matched cohort study, rTSA with or without concomitant LT results in significant improvements in patient-reported outcomes and rotational range of motion in patients with massive rotator cuff tears and limited preoperative ER. However, concomitant LT did not provide superior improvement in ER or overall functional outcomes compared with rTSA alone and was associated with early proximal humeral osseous erosion, the clinical significance of which remains unclear.

Level III, Retrospective Cohort Comparison, Treatment Study.