Impact of preoperative shoulder osteoarthritis severity score on outcomes after rotator cuff repair: A correlation study

Arthroscopic rotator cuff repair (ARCR) generally improves clinical outcomes, but the impact of pre-existing glenohumeral osteoarthritis (GHOA) severity on these outcomes remains unclear. This study aims to evaluate the correlation between preoperative GHOA severity, assessed via the Shoulder Osteoarthritis Severity (SOAS) score, and postoperative patient-reported outcomes (PROs) following ARCR with a minimum of two years follow-up. In this retrospective cohort study, 150 patients who underwent ARCR between 2018 and 2023 were included. Preoperative GHOA severity was assessed independently by two reviewers using magnetic resonance imaging (MRI) and graded using the SOAS score. PROs included the American Shoulder and Elbow Surgeons (ASES) score, University of California-Los Angeles (UCLA) score, and Western Ontario Rotator Cuff (WORC) index. Correlation and multivariate regression analyses were used to identify predictors of PROs. Receiver operating characteristic (ROC) curve was performed to assess the SOAS score’s predictive value. Of 150 eligible patients, the cohort had a mean age of 66.6 ± 8.8 years and a mean follow-up of 42.3 ± 14.5 months. Inter-reader reliability of total SOAS was excellent (ICC = 0.942). Higher total SOAS scores were significantly associated with lower ASES (r=–0.21, p = 0.012) and UCLA (r=–0.22, p = 0.006) scores. Subdomain analysis revealed that labral-bicipital complex pathology negatively correlated with all three PROs (ASES: r=-0.21, p = 0.010; UCLA: r=-0.20, p = 0.013; WORC: r=-0.18, p = 0.026), while cartilage degeneration correlated with lower UCLA score (r=-0.18, p = 0.033). On multivariate analysis, long head of biceps pathology was an independent predictor of a lower ASES score (β=–2.14, p = 0.029) and WORC index (β=–0.1, p = 0.032). An optimal SOAS cut-point of 17 for predicting failure showed poor discriminative ability (AUC = 0.596). The SOAS score demonstrated a significant correlation with Kellgren-Lawrence grading system (r = 0.71, p < 0.001). Although continuous GHOA severity correlates with lower postoperative scores, the overall SOAS score alone is a poor prognostic discriminator for clinical failure. Therefore, GHOA should not be considered an absolute contraindication for ARCR. A holistic preoperative assessment integrating these critical factors is essential for optimizing clinical decision making.