The effect of 12-month arthroscopic rotator cuff repair integrity on functional outcomes: a multi-centre study

Background Recurrent defects following arthroscopic rotator cuff repair are common. However, their relationship to functional outcomes and symptoms remains unclear. This study aimed to evaluate the association between rotator cuff repair integrity at 12 months and functional outcomes over a 24-month period. Materials and methods A total of 543 patients undergoing arthroscopic repair for rotator cuff tears were enrolled from nine orthopaedic centres. Clinical and patient-reported outcomes were assessed at baseline and at 6, 12, and 24 months. Medical imaging was performed at baseline and at 12 months. Patients were grouped according to the repair integrity at 12 months or the occurrence of a symptomatic recurrent defect within 12 months. Adjusted generalised linear mixed models were used to compare clinical and patient-reported outcomes. Results Overall, 299 asymptomatic patients underwent magnetic resonance imaging at 12 months ( n = 203 intact repairs, n = 41 partial recurrent defects, n = 55 full recurrent defects), and 31 patients out of 543 developed a symptomatic recurrent defects. Clinical and patient-reported outcomes improved postoperatively. Both asymptomatic recurrent defect groups showed comparable ranges of motion, abduction strength, and pain levels to the intact repair group ( P ≥ 0.071). The symptomatic recurrent defect group performed the worst overall ( P ≤ 0.009). The Constant score, Oxford Shoulder Score, Subjective Shoulder Value, and EQ-5D-5L Utility Index were similar between asymptomatic and intact repair groups ( P ≥ 0.086). The symptomatic group had the lowest proportion of patients (up to 81%) reaching an acceptable symptom state across the investigated scores, with significant differences compared with the intact repair group ( P ≤ 0.001). Current smoking and cartilage lesions of the humeral head and glenoid were more prevalent in the symptomatic group and showed a marked between-group difference. Conclusion Patients with asymptomatic recurrent defects performed comparably to those with intact repairs up to 24 months postoperatively. Patients with symptomatic recurrent defects showed clinically relevant deficits. Future predictive models should target symptomatic recurrent defects, allowing for customisation of patient-specific treatments and rehabilitation. Trial registration Ethical approval was obtained from the responsible ethics committee (Ethics Committee Northwest Switzerland EKNZ 2019-02076), and the study was registered at clinicaltrials.gov on March 24, 2020 (trial registration number NCT04321005, https://clinicaltrials.gov/ct2/show/NCT04321005 ).