Comparison of a Novel Modified All-Suture Construct versus Suspensory Suture-button Fixation in a Syndesmotic Injury Model.

Abstract

To biomechanically investigate a novel modified all-suture construct compared with commercially available suspensory button fixation for stabilization of the syndesmosis. Eight matched pairs of cadaver lower limbs were obtained. We used a material testing machine and Optotrak optoelectronic 3D motion measurement system for testing. Syndesmotic injuries were simulated, and specimens were fixed with either a suspensory suture button or modified all-suture construct. Repaired specimens were then cyclically loaded for 500 cycles. Spatial relationship of the tibia and fibula were continuously monitored for the intact, destabilized, and repaired states. The results were analyzed using independent samples t test. There was no significant difference in sagittal or coronal plane translation between intact and either repair. Compared with the intact state, both repair techniques demonstrated significantly more external rotation of the fibula relative to the tibia and decreased construct stiffness. Cycling of the specimens did not significantly increase coronal or sagittal plane translation; however, external rotation of the fibula relative to the tibia increased and stiffness decreased with cycling for both repair techniques. Our data suggest that sagittal and coronal plane translation is no different from the intact state for both fixation techniques. However, rotation of the fibula relative to the tibia was increased, and construct stiffness was decreased compared with the intact state for both fixation techniques. These findings suggest that an all-suture construct could offer syndesmotic fixation comparable with proprietary suspensory button fixation in a cadaver model.