ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION NUMERIC AND EXPERIMENTAL ANALYSES: INFLUENCE OF TRABECULAR BONE CONSTITUTIVE MODEL

Abstract

Abstract INTRODUCTION The number of variables that influence the success of an ACL reconstruction is such that, the use of numerical tools becomes increasingly necessary. In this work, a finite element model is developed to simulate the ACL reconstruction in its tibial insertion. MATERIAL AND METHODS Tibiae and ligaments porcine samples were used in this work. As the tibial fixation, an interference screw with a nominal diameter of 7mm and a length of 25mm is used. The plasty which replace the injured ligament was characterize using tensile tests. Uniaxial and confined compression tests, as well as indentation tests, were used for characterizing trabecular bone. Finite element methods were used for the implementation of the ACL reconstruction simulation, which studies the effect in the knee joint of all the elements involved (plasty, bone and interference screw). RESULTS None of the models available for the description of the trabecular bone behavior (von Mises, Hill and Crushable Foam), is capable of doing it in a completely proper manner. The use of one or the other constitutive model does not greatly influence the numerical simulation results. CONCLUSIONS As trabecular bone has a strongly anisotropic and non-symmetric mechanical behavior, none of the constitutive models available in the finite element code used is capable of fully describing it. Thus, the use of von Mises criterion is recommended, as it is the easiest to define and the one that requires the least numerical resources (lower computational cost).