Abstract
Background: Arthroscopic superior capsule reconstruction (SCR) was developed to restore shoulder superior stability, muscle balance, and function in patients with irreparable posterior-superior rotator cuff tears. Purpose: To assess the effects of concomitant subscapularis tendon tear, which may reduce glenohumeral stability and force coupling, on clinical outcomes of SCR for irreparable posterior-superior rotator cuff tears. Study Design: Cohort study; Level of evidence, 3. Methods: In total, 193 patients with irreparable posterior-superior rotator cuff tears underwent arthroscopic SCR using fascia lata autograft between 2007 and 2015. They were allocated to 3 groups: group 1, no subscapularis tear (160 patients); group 2, reparable subscapularis tear, which underwent arthroscopic repair (26 patients); and group 3, irreparable subscapularis tear (7 patients). American Shoulder and Elbow Surgeons (ASES) and Japanese Orthopaedic Association (JOA) scores, visual analog scale (VAS) score for pain, active shoulder range of motion (ROM), muscle strength (manual muscle test), and acromiohumeral distance were evaluated before surgery and at final follow-up (mean, 3 years, 7 months; range, 2-11 years). Postoperative complications were assessed. Results: In groups 1 and 2, ASES, JOA, and VAS scores and shoulder ROM and muscle strength improved significantly after SCR with subscapularis repair (P <.001). SCR in group 3 significantly improved ASES, JOA, and VAS scores (P <.001), whereas shoulder ROM and muscle strength did not increase significantly. Postoperative acromiohumeral distance was significantly smaller in group 3 (5.7 ± 2.9 mm [mean ± SD]) than group 2 (9.1 ± 2.3 mm) (P =.002). Group 3 had a significantly higher rate of graft tear (P <.001) and postoperative infection (P <.001) than group 1. Conclusion: The presence of subscapularis tendon tear affects clinical outcomes and complication rates after SCR. The reparability of the subscapularis affects superior glenohumeral stability; therefore, an intact subscapularis or reparable subscapularis tendon tear is the best indication for arthroscopic SCR in patients with irreparable posterior-superior rotator cuff tendon tears. © 2020 The Author(s).