Biomechanical Evaluation of a Transtendinous All-Suture Anchor Technique Versus Interference Screw Technique for Suprapectoral Biceps Tenodesis in a Cadaveric Model.

PURPOSE: To compare the biomechanical properties of an transtendinous all-suture anchor technique with the commonly-accepted interference screw technique in a cadaveric model.

METHODS: Sixteen fresh-frozen human cadaveric shoulders (mean age, 67.6 ± 5.8 years) were used and were randomly divided into 2 experimental long head of the biceps brachii (LHB) tenodesis groups (n = 8), namely transtendinous all-suture anchor technique and interference screw technique. The location of tenodesis was in the bicipital groove, 1 cm distal to the proximal border of the bicipital groove. Tensile force parallel to the longitudinal axis of the humerus was applied to each specimen. A preload of 5 N was applied for 2 minutes, followed by cyclic loading for 500 cycles from 5 to 70 N at 1 Hz; then, a load-to-failure test at 1 mm/s was performed. The ultimate failure load, stiffness, cyclic displacement, failure displacement, and failure modes were recorded.

RESULTS: The transtendinous all-suture anchor technique provided similar ultimate failure load and stiffness as the interference screw technique. However, the cyclic and failure displacements of the transtendinous all-suture anchor technique were significantly greater than the interference screw technique (P = .009 and .021, respectively). Six specimens in the transtendinous all-suture anchor group failed because of suture anchor pullout, while failure of the other 2 was caused by tendon tear; by contrast, all specimens in the interference screw group failed because of tendon tear.

CONCLUSIONS: The transtendinous all-suture anchor technique for LHB tenodesis offered equivalent ultimate failure load and stiffness but had significantly larger cyclic and failure displacement values when compared with the interference screw technique in this cadaveric biomechanical study.

CLINICAL RELEVANCE: The transtendinous all-suture anchor technique is an alternative technique for suprapectoral LHB tenodesis; however, care should be taken because only time zero biomechanical data are available.