Efficacy of bone marrow stimulation for arthroscopic knotless suture bridge rotator cuff repair: a prospective randomized controlled trial

The purpose of this study was to investigate the efficacy of bone marrow stimulation (BMS) on the repair integrity of the rotator cuff insertion treated with arthroscopic knotless suture bridge (K-SB) rotator cuff repair. We hypothesized that BMS during K-SB repair can improve the healing of the rotator cuff insertion.Sixty patients who underwent arthroscopic K-SB repair of full-thickness rotator cuff tears were randomly allocated to two treatment groups. Patients in the BMS group underwent K-SB repair augmented with BMS at the footprint. Patients in the control group underwent K-SB repair without BMS. Cuff integrity and retear patterns were evaluated by postoperative magnetic resonance imaging. The clinical outcomes included the Japanese Orthopaedic Association score, University of California at Los Angeles score, Constant-Murley score, and Simple Shoulder Test.Clinical and radiological evaluations were completed in 60 patients at 6 months postoperatively, in 58 patients at 1 year postoperatively, and in 50 patients at 2 years postoperatively. Both treatment groups showed significant improvements in the clinical outcome from baseline to the 2-year follow-up, but no significant differences were found between the two groups. At 6 months postoperatively, the retear rate at the tendon insertion was 0.0% (0 of 30) in the BMS group and 3.3% (1 of 30) in the control group (p = 0.313). The retear rate at the musculotendinous junction was 26.7% (8 of 30) in the BMS group and 13.3% (4 of 30) in the control group (p = 0.197). All retears in the BMS group occurred at the musculotendinous junction, and the tendon insertion was preserved. There was no significant difference in the overall retear rate or retear patterns between the two treatment groups during the study period.No significant differences were detected in the structural integrity or retear patterns regardless of the use of BMS. The efficacy of BMS for arthroscopic K-SB rotator cuff repair was not proven in this randomized controlled trial.