Distal Tibiofibular Ligament Injury Anatomic Reconstruction Research

Objective: To study the anatomic reconstructionmethod of the inferior tibiofibular ligament and its effect on the stability of the inferior tibiofibular syndesmosis.Methods: In the first part of the study,we dissect 10 cases of fresh specimens of the ankle joint in adult pigs, research its anatomical characteristics of inferior tibiofibular ligament and movement characteistics,compared with the anatomy of human ankle joint similarity, to establish the animal injury model of distal tibiofibular syndesmosis.Research the entry and exit points of bone tunnels for inferior tibiofibular ligament reconstruction, as well as the approach of walking and fixing of peroneus brevis tendon.Evaluate the effect on stability and physiological movement of distal tibiofibular syndesmosis of anatomic reconstruction. We measure the distance and direction of movement of distal fibula to tibia in the transverse and sagittal axis with Instron8874 biomechanical testing machine,research the change of the syndesmotic stability and physiological movement in four different conditions including inferior tibiofibular ligament intact, cut off completely, ligament anatomic reconstruction and fixtion with single 3.5mm cortical screws. In the second part of our study, we research the method of anatomic reconstruction of syndesmotic ligament with 10 fresh human ankle joint specimens, measure displacement direction and distance of distal fibular with respect to the tibia in the transverse and sagittal axis,compare its influence on the syndesmotic stability and physiological movement.The specimens was loaded with compression force in dorsiflexion 30 degree to 200N and external rotation torque force in 0 degree neutral position to 10Nm,respectively.Results: The syndesmosis ligament of pig are composed of anterior tibiofibular ligament, posterior tibiofibular ligament and interosseous ligament, similar to the human ankle joint structures, in line with the animal model of injury of distal tibiofibular syndesmosis. Operation technique of anatomic reconstruction of distal tibiofibular ligament with peroneus brevis tendon has the clinical feasibility and practicality. The distance and direction of distal fibular movement relative to the tibia have no significant difference in the anatomic reconstruction and physiological state. Anatomic reconstruction of inferior tibiofibular ligament can restore the stability of the syndesmosis, and also allow its physiological movement.Conclusion The syndesmosis of the pig has the similar construction to the human ankle joint structure, in line with the animal injury model of distal tibiofibular syndesmosis. Operation technique of anatomic reconstruction of distal tibiofibular ligament with peroneus brevis tendon has the clinical feasibility and practicality.Anatomic reconstruction of inferior tibiofibular ligament can restore the stability of the syndesmosis, and also allow its physiological movement.