High Repair Tension and Advanced Age Negatively Affect Subscapularis Healing Status After Arthroscopic Rotator Cuff Repair.

PURPOSE: To (1) investigate the relationship between repair tension and radiologic outcomes and (2) identify cutoff values of associated factors that predict both radiologic and clinical outcomes after arthroscopic subscapularis (SSC) repair.

METHODS

This retrospective study included patients who underwent SSC repair and completed a 2-year follow-up between September 2020 and March 2022. Intraoperative evaluations examined the retraction length, repaired tendon, and Lafosse classification. Magnetic resonance imaging was performed before surgery and at 6 months postoperatively to evaluate the severity of the tear, fatty infiltration, and healing status of the SSC and supraspinatus. Functional scores and internal rotation strength were measured before surgery and at 6, 12, and 24 months postoperatively. Multiple logistic regression was performed to identify variables associated with poor healing, with receiver operating characteristic curves determining cutoff values.

RESULTS

A total of 67 patients were included. The mean SSC repair tension was 3.72 ± 1.48 kg. Poor healing was observed in 25.4% of the patients, with significant differences in age (P = .004), repair tension (P = .002), retraction length (P = .033), and Lafosse classification (P = .035) observed between the adequate and poor healing groups. Multiple logistic regression revealed significantly increased odds ratios for poor SSC healing in patients older than 65 years and patients with repair tension exceeding 4 kg.

CONCLUSIONS

Poor SSC healing is associated with advanced age, increased repair tension, greater retraction length, and more severe Lafosse classification. Patients older than 65 years and those with repair tension exceeding 4 kg are at a significantly higher risk of poor SSC healing. Furthermore, patients with poor SSC healing exhibit significantly reduced internal rotation strength at 24 months postoperatively. However, no significant decline was observed in shoulder function scores or achievement of the minimal clinically important difference.

LEVEL OF EVIDENCE: Level III, retrospective cohort study.