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

Abstract

BackgroundReverse 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. MethodsFifty patients (f: 36, m:14) 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. ResultsTwelve 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%. ConclusionWhile 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.