Role of Ligaments in the Knee Joint Kinematic Behavior: Development and Validation of a Finite Element Model

Abstract

The management of knee instability is a complex problem in orthopedic surgery. To comprehensively assess the biomechanical role of the knee joint and to investigate various aspects of knee mechanics, several Finite Element (FE) knee models have been developed. However, (i) the full validation of these models against tibio-femoral and tibio-patellar kinematic data and (ii) the high numerical costs associated with the computation of the biomechanical response of the knee joint are still main issues. Moreover, the contribution on knee mobility of the different ligaments is still unclear. The aim of this study was therefore to develop an FE model with both extensive validation and low computational for the investigation of the role of ligaments in the joint kinematic behavior. To this end, a 3D FE model, consisting of the distal and proximal part of the femur and tibia, respectively, the patella, the quadriceps tendon, the cartilage, and knee ligaments was developed in ANSYS. For the model evaluation, 23 fresh frozen knee joints were tested in flexion/extension using a validated device. The model-predicted response was within or at the limits of the experimental corridors for all translations and rotations of tibia and patella with regard to the femur. A sensitivity analysis was conducted to evaluate the impact of both the stiffness and initial strain of ligaments on the knee kinematic response. Our results showed the high sensitivity of the model to the mechanical parameters of the ligaments.