Braided tape is equivalent to modified Mason-Allen multi-strand #2 suture in subscapularis muscle repair: results of a biomechanical study

Background To help determine the optimal fixation method for subscapularis tendon repair in arthroplasty, the present study compares single-passage transosseous tape (BT) and modified Mason-Allen #2 suture (MA). Methods Eighteen human cadaveric shoulders were randomized to two repair constructs after arthroplasty preparation. Both techniques included two transosseous passages through the bicipital groove and then through the tendon at the level of the anatomical neck. Construct was tested using a traction machine, measuring cyclic loading and ultimate load to failure. Results The mean age of our specimens was 71 years. No significant difference was observed between the repair techniques in both mean ultimate load and cyclic loading. The mean (SD) ultimate load (UL) for BT was 293 (84) N and 342 (117) N for MA, which was not statistically significant (p = 0.374). The majority of repairs failed in the tendon. Bone cut-out was observed with the MA but not for the BT repair. No correlation was found between bone density and UL for BT (r = −0.09) but there was strong correlation for MA (r = 0.63). Conclusions The MA repair appears to be more dependant on bone mineral density for ultimate load, indicating that braided-tape might be better suited for osteoporotic patients to avoid bone cut-out.