No Functional Difference Between Three and Six Weeks of Immobilization After Arthroscopic Rotator Cuff Repair: A Prospective Randomized Controlled Non-Inferiority Trial

Abstract

The aim of this study was to compare clinical and radiologic results among patients with 3 versus 6weeks of immobilization after arthroscopic rotator cuff (RC) repair in a prospective randomized controlled non-inferiority trial. One hundred twenty patients were included after RC surgery for a small- to medium-sized tear of supraspinatus and upper infraspinatus tendons. Group A was immobilized in a simple sling for 3weeks, and group B had a brace with a small abduction pillow with the arm in neutral position for 6weeks. All patients started active range of motion when they removed the sling/brace. One hundred eighteen (98%) patients were assessed at 1-year follow-up. They underwent magnetic resonance imaging (MRI) of the shoulder, filled out the Western Ontario Rotator Cuff (WORC) index, and were evaluated with a Constant Murley (CM) score. Statistical non-inferiority was demonstrated for the 2 groups on the basis of the WORC index, the primary endpoint at 1year. The objective for the non-inferiority test was to determine whether the expected mean WORC index for group A was at most 13% worse than standard treatment (Group B). The WORC index at 1year was similar in both groups, with mean percent scores of 83% in group A and 87% in group B (mean difference=-4; 95% one-sided CI-9,-4). Age-adjusted CM scores were also similar, with means of 86 in group A and 90 in group B (mean difference=-4; 95% CI-13, 5; P= .37). MRI after 1year showed 50 (89%) patients in each group with healed RC repair. Four patients in group A had complications: 1 acute postoperative infection, 2 cases of postoperative capsulitis treated with corticosteroid injections, and 1 repeat operation because of a loose anchor and subacromial pain. No patients in group B had complications. RC repair resulted in improved postoperative shoulder function, regardless of whether the shoulder was immobilized for 3 or 6weeks. Three weeks of postoperative immobilization with sling use was non-inferior to the commonly used regimen involving 6weeks of immobilization in a brace with regard to the WORC index at 12months' follow-up. MRI indicated similar degrees of healing between the groups. Based on these findings, it is safe to immobilize patients in a simple sling for 3 to 6weeks after repair of small to medium RC tears. Level I, high-quality randomized controlled trial with statistically significant differences.