A biomechanical comparison of two arthroscopic suture techniques in biceps tenodesis: whip-stitch vs. simple suture techniques

Abstract

The aim of this study was to compare the biomechanical performance of whip-stitch (WS) and simple suture techniques (SST) of the long head of the biceps tendon in suprapectoral intraosseous tenodesis with interference screw fixation. A total of 10 paired cadavers (61.1 ± 4.6 years) were randomized to receive WS or SST biceps tenodesis beginning at the musculotendinous junction. Both groups implemented a No. 2 FiberLoop wire and underwent suprapectoral fixation with a polyetheretherketone interference screw at the bicipital grove. A Materials Testing System performed cyclic testing (500 cycles), followed by load to failure at 1 mm/s. Load, displacement, and time were recorded during cyclic and failure testing. A 2-tailed Student's t-test and χ2 analysis were performed for failure load and mode of failure, respectively. Two SST specimens and 1 WS specimen failed during cyclic loading via tendon rupture at the screw-tendon interface. There was no significant statistical difference in the cyclic displacement after 500 cycles between the WS (12.9 mm ± 4.4 mm) and SST groups (14.0 mm ± 3.8 mm, P = .2); cyclic strain, defined as the peak displacement at the 500th cycle divided by the initial gauge length, betweenthe WS (0.4 ± 0.2) and SST groups (0.7 ± 0.7, P = .3); maximal load (162.7 N ± 56.8 N vs. 153.1 N ± 39.3 N, respectively, P = .6); and stiffness (50.5 N/mm ± 17.7 N/mm vs. 43.3 N/mm ± 10.9 N/mm, respectively, P = .3). All specimens ruptured at the screw-tendon interface. The WS technique can provide equivalent biomechanical performance to the SST in suprapectoral intraosseous biceps tenodesis with interference screw fixation.