Repair with bicortical suspension device restores proximal tibiofibular joint motion.

Purpose: Dislocation of the proximal tibiofibular joint is a complex injury that is often overlooked or misdiagnosed. Surgical treatment is recommended for severe acute or for chronic symptomatic instability but there is still no evidence on the optimal reconstruction technique. The purpose of this study is to analyze the motion of the proximal tibiofibular joint after repair with a bicortical suspension device as compared to its normal kinematics.

Methods: Kinematic analysis of the proximal tibiofibular joint was performed during continuous passive motion of the knee and ankle in 7 whole body cadavers in a controlled laboratory study. The 14 knees were measured in four conditions: (1) intact; (2) repair with transarticular bicortical suspension device tensioned to 40 N; (3) the same repair tensioned to 50 N; and (4) the repair tensioned to 50 N after interosseous syndesmotic membrane sectioning.

Results: Proximal tibiofibular joint can be successfully repaired by a bicortical suspension device restoring its normal 3D spatial motion. The fixation of the PTFJ with the device tested tensioned to 40 or 50 N could restore the intact joint kinematics for every movement tested except knee internal and external rotation. The fixation to 40 N attained closer values to the intact joint in the movements that evolve the anterior PTFJ ligament. The 50 N fixation is overall more rigid than the intact joint but statistically closer to the normal PTFJ kinematics for the movements more dependent on the posterior PTFJ ligament. Sectioning of the interosseous syndesmotic membrane determined an important loss of stability of the PTFJ during the movements of ankle extension and ankle flexion. Such loss illustrates the relevance of this associated injury when planning PTFJ ligament reconstruction.

Conclusions: This study indicates that the repair of the proximal tibiofibular joint with a transarticular bicortical suspension device tensioned to 40 and 50 N can restore the normal kinematics of this joint. Based on these findings, Surgeons may consider this option as a reliable solution when planning successful treatment for proximal tibiofemoral joint instability.