Modified double-pulley suture-bridge techniques with or without medial knot tying show comparable clinical and radiological outcomes in arthroscopic rotator cuff repair

Purpose The optimal technique for arthroscopic rotator cuff repair is still controversial. The aim of this study was to compare modified arthroscopic double-pulley suture-bridge (DPSB) technique with medial knot tying to those without tying, considering clinical and radiological outcomes. Methods This study included 292 patients with large full-thickness rotator cuff tears treated with modified DPSB technique. The patients were divided into 158 cases with medial knot tying (knot-tying group) and 134 without tying (knotless group). At follow-up, clinical outcome was assessed by the Constant score, American Shoulder and Elbow Surgeons (ASES) score, and Shoulder Rating Scale of the University of California at Los Angeles (UCLA) score. The assessment of tendon healing was performed with magnetic resonance imaging (MRI) at a minimum of 12 months postoperatively. Results The Constant score, ASES score and UCLA score in the knot-tying and knotless groups all improved significantly from before surgery to 12 months postoperatively (P < 0.05, respectively). No significant differences were observed between groups for each phase evaluated (n.s.). Tendon healing was categorised according to Sugaya's classification. The retearing rate was 27/158 (17.0%) in the knot-tying group and 20/134 (14.9%) in the knotless group, with no statistically significant difference between groups (n.s.). Additionally, the retear was classified using the Cho's classification. When comparing the retear rates of different types independently, no statistically significant differences were found between groups (n.s.). Conclusions The knotless modified DPSB technique showed comparable short-term functional outcomes to those of the knot tying method in large full-thickness rotator cuff tears. Additionally, no significant differences in repair integrity were observed between the two methods. Both techniques can be considered effective treatments for patients with large-sized full-thickness rotator cuff tears.