Tendon stump change as a risk factor for structural failure of arthroscopic rotator cuff repair.

BACKGROUND

This study aimed to identify risk factors for retear after arthroscopic rotator cuff repair (ARCR) using the suture bridge method and to assess the relation between preoperative and postoperative tendon condition and retear.

METHODS

We retrospectively analyzed patients who underwent ARCR for a medium tear. Potential risk factors, including tear width, anteroposterior and medial-lateral tear width, atrophy, fatty degeneration, and condition of the tendon stump (Ishitani's classification and rotator cuff/deltoid muscle [C/D] ratio), were identified on magnetic resonance preoperatively. Magnetic resonance imaging was performed regularly after surgery, and the C/D ratio in the sutured cuff was evaluated. Shoulders that were Sugaya type I-III were classified as the repair group and those that were type IV or V as the retear group. Risk factors for retear were analyzed by univariable and multivariable analyses.

RESULTS

We analyzed 175 patients in 183 shoulders. The overall retear rate was 13.1%. Multivariable analysis revealed medial-lateral width (odds ratio: 0.88; 95% confidence interval: 0.82-0.95; P < .001) and C/D ratio (odds ratio: 0.30; 95% confidence interval: 0.16-0.58; P < .001) as independent risk factors for retear. At 3 weeks postoperatively, the C/D ratio was significantly higher in the retear group (1.70 ± 1.47 vs. 0.84 ± 0.72; P = .002).

CONCLUSIONS

The C/D ratio and tear width were risk factors for retear after ARCR using the suture bridge method. The C/D ratio was higher in retear cases both preoperatively and postoperatively.