Suture Tape Reinforcement Device as an Independent Fixation Solution for Partial Syndesmosis Injuries

CATEGORY: Ankle; Arthroscopy; Basic Sciences/Biologics; Sports INTRODUCTION/PURPOSE: A suture tape reinforcement device is designed for repair of syndesmotic injury. Its insertion in the fibular and tibial footprints of the anterior inferior tibiofibular ligament (AITFL) promises a dynamic constraint to external rotation, antero-posterior translation of fibula and diastasis of the syndesmosis in the coronal plane.We hypothesized that following fixation of transected syndesmosis with suture tape reinforcement, syndesmotic stability becomes similar to that of an intact syndesmosis. METHODS: Fifteen non-paired fresh frozen cadaveric specimens amputated above the knee were included in this study. Assessment of the ankle syndesmosis was performed in six stages; 1) with all syndesmosis ligaments intact; 2) after transection of the AITFL, 3) the interosseous ligament, 4) subsequent fixation with suture tape reinforcement device, 5) transection of the posterior inferior syndesmotic ligament, and 6) after removal of the suture tape reinforcement device (complete ligament transection stage). Instability measurements included anterior and posterior tibiofibular spaces measured arthroscopically under 100N lateral stress using a bone hook, tibiofibular anteroposterior and posteroanterior translation in sagittal plane measured arthroscopically under sagittal stress of 100N, and anterior tibiofibular space measured directly with a caliper under external rotation torque of 7.5 Nm. Instability measurements taken after each fixation method were compared with the intact stage and to the complete ligament transection stage using the Wilcoxon signed-rank test. RESULTS: The suture tape reinforcement device was able to stabilize an AITFL- and the interosseous ligament-transected stage, similar to the intact stage, with respect to all measures of instability. As for the complete ligament transection stage, after suture tape reinforcement it remained unstable in the coronal plane, compared to the intact stage: there was an increase in anterior tibiofibular space without stress (1.7 mm vs 1.1 mm, p=0.005) and with stress (1.8 mm vs 1.1 mm, p=0.007), as well as in posterior tibiofibular space with stress (2.8 mm vs 1.6 mm, p=0.002). CONCLUSION: Our findings suggest that suture tape reinforcement device might be effective for fixation of partial syndesmotic injury, but not for complete syndesmotic injury. Future clinical research is needed to confirm this.