Combined tears of the subscapularis and supraspinatus tendon: clinical outcome, rotator cuff strength and structural integrity following open repair

Background Anterosuperior rotator cuff tears involving the subscapularis and supraspinatus tendons are less common than other tears of the rotator cuff. The purpose of this study was to report the clinical outcome, rotator cuff strength and structural integrity of open repair of combined anterosuperior rotator cuff tears. Patients and methods Forty-eight patients at an average age of 58 years underwent open repair of a combined supraspinatus and subscapularis tendon tear. The follow-up evaluation included clinical scores, rotator cuff strength testing with a custom-made force measurement plate (FMP) and postoperative MRI to evaluate repair integrity and muscle cross-sectional area. Results After a mean follow-up of 49 months the average Constant score improved from 43 points preoperatively to 79 points postoperatively. The SST and the pain VAS were significantly improved by the procedure (each < 0.05). The combined tear group with partial subscapularis tears (G1) did not achieve significantly better score results than the combined tear group with a full-thickness subscapularis tear (G2) (p > 0.05). Strength for all rotator cuff components was reduced significantly (p < 0.05) compared with the contralateral shoulder in both groups. MRI revealed a retear-rate of 4% for the subscapularis and a retear-rate of 19% for the supraspinatus. Postoperative muscle cross-sectional area of all rotator cuff muscles did not differ significantly between G1 and G2 (p > 0.05). Conclusion Open repair of combined anterosuperior rotator cuff tears achieved good postoperative results despite a residual rotator cuff strength deficit. Combined supraspinatus-/full-thickness subscapularis tears achieved equal clinical and radiographic results compared with supraspinatus-/partial-thickness subscapularis tears.