Ulnar collateral ligament reconstruction using bisuspensory fixation: a biomechanical comparison with the docking technique.

BACKGROUND: Many ulnar collateral ligament (UCL) reconstruction techniques have been created and biomechanically tested. Single-bundle reconstructions aim to re-create the important anterior bundle of the UCL. To date, no technique has utilized suspensory fixation on the ulnar and humeral sides to create a single-bundle reconstruction. HYPOTHESIS: The bisuspensory technique will restore valgus laxity to its native state, with comparable load-to-failure characteristics to the docking technique. STUDY
DESIGN: Controlled laboratory study.
METHODS: Six matched pairs of fresh-frozen cadaveric elbows were randomized to undergo UCL reconstruction using either the docking technique or a novel single-bundle bisuspensory technique. Valgus laxity and rotation measurements were quantified using a MicroScribe 3DLX digitizer at various flexion angles for the native ligament, transected ligament, and 1 of the 2 tested reconstructed ligaments. Laxity testing was performed from maximum extension to 120° of flexion. Each reconstruction was then tested to failure, and the method of failure was recorded.
RESULTS: Valgus laxity was restored to the intact state at all degrees of elbow flexion for both the docking and bisuspensory techniques. In load-to-failure testing, there was no significant difference with regard to stiffness, ultimate torque, ultimate torque angle, energy absorbed, and applied moment to reach 10° of valgus. Yield torques for the bisuspensory and docking reconstructions were 18.7 ± 7.8 N·m and 18.6 ± 4.4 N·m, respectively (P = .95). The ultimate torque for the bisuspensory technique measured 26.5 ± 9.2 N·m and for the docking technique measured 25.1 ± 7.1 N·m (P = .78).
CONCLUSION: The bisuspensory fixation technique, a reproducible single-bundle reconstruction, was able to restore valgus laxity to the native state, with similar load-to-failure characteristics as the docking technique. CLINICAL RELEVANCE: This reconstruction technique could be considered in a clinical setting as a primary method of UCL reconstruction or as a backup fixation method should intraoperative complications occur.