Open biceps tenodesis: A biomechanical comparison of 6 fixation techniques

Tenodesis is used to treat pathology of the long head of the biceps tendon. The authors evaluated the biomechanical properties of 6 techniques for biceps tenodesis fixation. The authors dissected 42 fresh-frozen cadaveric shoulders (mean age, 71±9.8 years; 69% male specimens), leaving the proximal humerus, proximal biceps tendon, and pectoralis major insertion. Specimens were randomized to undergo biceps tenodesis with one of the following: (1) an interference screw; (2) a cortical button; (3) a double-loaded 2.9-mm polyetheretherketone anchor (DL-2.9); (4) a double-loaded 1.9-mm all-suture anchor (DL-1.9); (5) a single-loaded 1.7-mm all-suture anchor (SL- 1.7); or (6) soft tissue tenodesis. Specimens then underwent load-to-failure axial traction testing. A generalized linear and latent mixed model with a random-effects term was used to account for specimen pairing. Mean failure loads ranged from 136 N (95% confidence interval, 103-169 N) in the cortical button group to 79 N (95% confidence interval, 58-99 N) in the interference screw group. Failure occurred most often when fixation sutures pulled out of the tendon; however, 7 specimens failed elsewhere. No significant differences in ultimate failure load were found by treatment group. The interference screw group showed significantly more weakness than the cortical button and DL-2.9 groups. Tendon quality and suture parameters are likely more important than the fixation technique in determining failure load.