Arthroscopic rotator cuff repair: A biomechanical comparison of the suture-bridge technique vs. a new transosseous technique using SutureButtons®

BackgroundThe suture-bridge technique using anchors as established transosseous-equivalent technique in arthroscopic rotator cuff repair was compared to a modified transosseous technique suitable for arthroscopic cuff repair.MethodsIn 10 fresh-frozen matched pairs of human cadaveric shoulders (mean age 67.1, SD 8.5 years), two different surgical techniques of cuff repair were tested: Group 1, using the suture-bridge technique with suture anchors, and Group 2, using two transosseous tunnels with SutureButtons®. Lateral row fixation was performed in both groups using knotless implants. Cyclic displacement to gap formation of 2 and 5 mm, linear stiffness, yield load, ultimate load, and mode of failure were recorded.FindingsGap formation at the tendon-to-bone interface of 2 mm occurred after a mean of 219.5 (SD 590.7) cycles in Group 1 and after 750.0 (SD 1566.1) cycles in Group 2. Gap formation of 5 mm occurred after 2331.6 (SD 2033.9) cycles (Group 1) and 2364.5 (SD 1994.2) cycles (Group 2), respectively. The yield and ultimate loads were 316.9 (SD 114.1) N and 375.9 (SD 131.2) N in Group 1, and 311.0 (SD 97.2) N and 363.8 (SD 107.6) N in Group 2, respectively. The linear stiffness was 40.3 (SD 10.4) N/mm in Group 1, and 41.6 (SD 13.2) N/mm in Group 2. There were no statistically significant intergroup differences.InterpretationThe new transosseous technique using SutureButtons® achieves equivalent biomechanical properties to the established suture-bridge technique using anchors. A tendentially reduced primary gap formation may be of importance for repair healing during the early phase of rehabilitation.