Biomechanical comparison of the three techniques for arthroscopic suprapectoral biceps tenodesis: implant-free intraosseous tendon fixation with Cobra Guide, interference screw and suture anchor.

PURPOSE: A new arthroscopic technique with Cobra Guide (CG) was developed to enable fast, controlled and strong intraosseous biceps tenodesis while avoiding an implant. The purpose of this study was to compare the newly developed suture-only biceps tenodesis technique [arthroscopic suprapectoral intraosseous implant-free biceps tenodesis (ASIIBT) with the new CG] to classical interference screws (IS) and suture anchors (SA) in terms of construct resistance to failure.

MATERIALS AND METHODS: Fifty-eight human cadaveric shoulders were randomized into three treatment groups. Twenty shoulders received an IS, 19 SA and 19 ASIIBT. A biceps tenodesis was performed according to the techniques listed above. Cyclic loading tests on a dynamic loading testing device were used to measure and compare the resistance to failure pullout between the three groups. Hartley's Fmax test and Tukey's Honest Significant Difference method were used for statistical analysis.

RESULTS: The construct with the greatest resistance was ASIIBT. Its resistance was statistically higher compared to the IS technique (p = 0.001). Resistance compared to the SA technique was not statistically significant (p = 0.123), although in seven cases ASIIBT resisted more than 50 cycles at 200 N, while the SA technique reached 50 cycles at 200 N in just two cases. During cyclic loading, each specimen failed at the tenodesis site.

CONCLUSIONS: ASIIBT showed higher failure loads compared with IS and SA. Better construct performance of ASIIBT is due to greater absorption of distension forces which may improve final tenodesis healing. Also, the absence of an implant lowers additional costs and the chances for postoperative complications may be decreased significantly.