Numerical investigation of human knee joint for understanding the influence of anterior cruciate ligament on the displacement and stress

This study aims at understanding the response of human knee joint during normal loading. Magnetic resonance images (MRI) of five healthy human knee joints were considered for this study. Three-Dimensional (3D) models of these knee joints were generated. Finite element analysis was undertaken on these models after their discretisation. A load of 134 N along with corresponding boundary conditions was applied on these human knee joint models. Linear elastic material properties were considered for all the parts. Ruptured anterior cruciate ligament (ACL) under the same load and boundary conditions as earlier was simulated. The maximum von-Mises stress was observed to be in the expected regions of ACL with the mean stress being 13.934 ± 5.1 MPa. The higher displacement and reduced stress observed in the knee joint with ruptured ACL when compared with that of healthy knee joint indicates that the joint becomes more flexible in the absence of ACL.