Subject-specific assessment of loading variation in the knee ligaments with a view to preoperative planning

The human knee joint is a complex joint of the human body that experiences large loads. The knee stability is mainly ensured by four major ligaments, which all play vital roles to enable a proper joint articulation. As such, the interactions between the mechanical loading in these ligaments needs to be taken into account in order to obtain an adequate assessment of rehabilitation after injury or preoperative planning to restore the function of a damaged ligament. However, the combined effect of knee ligaments during movement has not yet been investigated in detail. In this study, we present a three-dimensional finite element model of a healthy human knee including the four major ligaments. The geometric model of the knee was reconstructed from volumetric data obtained from MR scans. Transversely isotropic Mooney-Rivlin material with fiber orientation was used to represent the mechanical response of the ligaments. For validation, anterior-posterior tibia translations were compared with the results obtained with an in vitro technique performed on cadavers. The purpose of these simulations is to simultaneously evaluate the mechanical behavior of the major ligaments of the knee. The good agreement between the 3D model and the in vitro measurements supports the potential for clinical applications of the model for evaluation of interventions or treatments.