Does the subscapularis refixation affect the clinical outcome after primary reverse shoulder arthroplasty?

ABSTRACT

BACKGROUND: Reverse shoulder arthroplasty is an established procedure for patients with rotator cuff tear arthropathy. However, the refixation of the subscapularis tendon remains a controversial and frequently discussed topic. This prospective randomized study was conducted to evaluate the clinical benefit of the subscapularis refixation after reverse shoulder arthroplasty. METHODS: Fifty patients (f 36, m14) were randomized and assigned to either the "repaired" (rep) or the "not repaired" (nrep) cohort. Intraoperatively, the subscapularis tendon was reattached in the rep-cohort with four tendon-to-tendon sutures, whereas no refixation was performed in the nrep-cohort. The Constant-Murley Score (CS) and the range of motion was evaluated preoperatively as well as 12 and 36 months postoperatively. The Subjective Shoulder Value (SSV) and the Lift-off test were performed 36 months postoperatively. The postoperative subscapularis integrity was assessed sonographically. RESULTS: Twelve months postoperatively the rep-cohort presented better results in the CS (rep 71 vs. nrep 66, p 0.037). The normalized CS was 80% in the rep-cohort and 75% in the nrep-cohort (p 0.114). At our last follow-up after 36 months we did not find significant differences between the rep-cohort and the nrep-cohort in the CS (rep 76 vs. nrep 75, p 0.285) and normalized CS (rep 91% vs. nrep 91%, p 0.388). Concerning internal rotation (in points) the rep-cohort achieved better results than the nrep-cohort (rep 7.3 vs. nrep 6.6, p 0.040). Flexion (rep 145° vs. nrep 151°, p 0.826), abduction (rep 135° vs. nrep 137° p 0.816), external rotation (rep 34° vs. nrep 37°, p 0.817) and the SSV (rep 81% vs. nrep 77%, p 0.398) presented no significant differences between the cohorts. The ultrasound examination after 36 months displayed an intact tendon in 70%. CONCLUSION: While the subscapularis refixation effects the postoperative internal rotation positively, there were no differences in mid-term follow-up concerning the overall results after rTSA. Further, the external rotation is not affected by the refixation of the subscapularis tendon.