Arthroscopic Side-to-side Repair for Large U-shaped Full-Thickness Rotator Cuff Tears: Is the Repair Integrity Actually Maintained?

Purpose: To evaluate the clinical and structural outcomes of arthroscopic side-to-side repair of large U-shaped full-thickness rotator cuff tears (FTRCTs) by assessing the functional score of the patients and the integrity of the tendon repair using magnetic resonance imaging with a minimum follow-up duration of 2 years. Methods: In this case series, 59 consecutive patients who underwent arthroscopic side-to-side repair of large U-shaped FTRCTs, with a minimum follow-up duration of 2 years (range 25 to 72 months), were retrospectively enrolled. The mean patient age was 58.6 years. Patients' functional scores and integrity of the tendon repairs were evaluated. Results: The mean visual analog scale score improved from 5.7 +/- 2.1 preoperatively to 2.4 +/- 1.3 postoperatively (P < .001). The mean range of motion (forward flexion) improved from 152.7 degrees +/- 11.4 degrees to 164.5 degrees +/- 9.5 degrees (P < .001). The mean Constant-Murley score improved from 57.3 +/- 7.2 preoperatively to 77.8 +/- 6.9 postoperatively (P < .001). Postoperative magnetic resonance imaging examinations demonstrated cuff integrity with a retear rate of 54.2%. The retear rate of patients who underwent anchor fixation to the medial row (45%) was significantly lower than that of patients who underwent simple side-to-side repair (73.7%) (P = .039). The University of California at Los Angeles shoulder rating and Constant-Murley scores were not significantly different between the healed and retear groups (P = .639 and P = .863, respectively). Conclusions: Arthroscopic side-to-side repair of large U-shaped FTRCTs demonstrated satisfactory clinical outcomes. However, the retear rate was higher than expected when simple side-to-side fixation was performed without footprint fixation. Therefore, medial row fixation is recommended if arthroscopic side-to-side repair is performed.