BackgroundThis study aimed to evaluate the efficacy of preemptive middle glenohumeral ligament (MGHL) release during arthroscopic rotator cuff repair (ARCR) of small- to medium-sized tears to prevent postoperative stiffness. MethodsPatients who underwent ARCR of small- to medium-sized tears were enrolled and allocated into two groups retrospectively: the preemptive MGHL release group (MGHL+ group, n=34) and preemptive MGHL non-release group (MGHL- group, n=32). The rotator interval and coracohumeral ligament release were performed in all patients with or without MGHL release in both groups. Clinical outcomes including the range of motion (ROM), Constant Shoulder (CS) score, and University of California, Los Angeles (UCLA) score preoperatively and at 3 months, 6 months, and 12 months postoperatively and complications were assessed and compared between the two groups. The integrity of the repaired tendon was assessed at the 12-month follow-up using magnetic resonance imaging. ResultsThe MGHL+ group showed a significantly higher external rotation, CS score, and UCLA score than the MGHL- group at 6 months postoperatively (P=.03, <.001, .01, respectively). The ROM and functional scores were not significantly different between the groups at 3 and 12 months postoperatively (P>.05). The retear rate, postoperative stiffness, and postoperative instability were not significantly different between the groups (all, P>.05). ConclusionsPreemptive MGHL release in ARCR of small- to medium-sized tears could be an effective method to prevent early postoperative shoulder stiffness but does not significantly change the overall clinical outcome after ARCR.