Finite element modeling and mechanical analysis on supination-external rotation ankle injury / 医用生物力学

ABSTRACT

Objective To simulate the supination-external rotation ankle injury and establish a 3D finite element model of the ankle. Methods Based on CT images of the normal human ankle joint, the 3D model of the ankle with ligaments was established. The supination-external rotation ankle injuries with four different degrees of Lauge-Hanson were analyzed by finite element method. Distributions of the ankle joint stress and tibial articular surface pressure were obtained. Results The maximum stress was at the anterior tibiofibular ligament attachment point of the tibial under supination-external rotation loading. When the anterior tibiofibular ligament was ruptured, the maximum stress was at the interosseous membrane. After the interosseous membrane was ruptured, the high stress was at the posterior ligament of the ankle. When the posterior tibiofibular ligament was ruptured, the high stress was at the deltoid ligament. The high pressure was at the distal fibula or the rear of tibial articular surface. Conclusions The established ankle-foot 3D numerical model can be used for the mechanical analysis of supination-externalrotation ankle injury. The calculated distributions of the ankle stress and the tibial articular surface pressure were in agreement with the description of Lauge-Hanson classification.