Repair Integrity and Retear Pattern After Arthroscopic Medial Knot-Tying After Suture-Bridge Lateral Row Rotator Cuff Repair

Background: Type 2 failure is a big issue after suture-bridge rotator cuff repair, which may be because of stress concentration at the medial row stitches. We have been performing medial knot-tying after suture-bridge lateral row repair to avoid the stress concentration. This study aimed to evaluate clinical and radiological outcomes after arthroscopic rotator cuff repair using this technique. Hypothesis: This technique would yield better radiological outcomes with a reduced type 2 failure rate compared with reported outcomes after conventional suture-bridge repair. Study Design: Case series; Level of evidence, 4. Methods: The inclusion criteria of this study were (1) full-thickness tears, (2) primary surgery, and (3) minimum 2-year follow-up with pre- and postoperative magnetic resonance imaging (MRI). We investigated active ranges of motion (forward elevation and external rotation), as well as the Japanese Orthopaedic Association (JOA) and University of California, Los Angeles (UCLA), scores preoperatively and at the final follow-up. Results: This study included 384 shoulders in 373 patients (205 men and 168 women) with a mean age of 65 years (range, 24-89 years) at the time of surgery. The mean follow-up was 29 months (range, 24-60 months). There were 91 small, 137 medium, 121 large, and 35 massive tears. Postoperative MRI scans demonstrated successful repair in 324 shoulders (84.4%, group S) and retear in 60 shoulders (15.6%). Among 60 retears, 40 shoulders (67%) had type 1 failure (group F1) and 20 shoulders (33%) had type 2 failure (group F2). Forward elevation and external rotation significantly improved after surgery ( P < .001 for both). Postoperative JOA and UCLA scores in group F2 were significantly lower than those in the other groups. Conclusion: The medial knot-tying after suture-bridge lateral row repair demonstrated excellent functional and radiological outcomes after surgery, with a retear rate of 15.6%. The type 2 failure showed significantly inferior functional outcomes; however, the rate of type 2 failure was less relative to previous studies using conventional suture-bridge techniques. Our technique could be a good alternative to conventional suture-bridging rotator cuff repair because it may reduce the rate of postoperative type 2 failure.