Change in Contact Conditions of Knee Joint Caused by Total Knee Replacement and Its Effect : Investigation on Two-Dimensional Model during Gait

Total knee replacement changes the shape of articular surfaces and the condition of cruciate ligaments depending on the type of artificial knee joint used. This affects the contact conditions between femur and tibia. In order to evaluate and improve the performance of artificial knee joints, it is necessary to determine the variation of contact conditions to which the components are subjected. In this study, contact conditions during gait were calculated using motion analysis, inverse dynamics and non-linear optimization methods for a two-dimensional lower limb model, and stress analysis of the fixation interfaces of tibial components was performed. Results indicated that differences in the shape of articular surfaces and the condition of cruciate ligaments led to marked differences in the contact conditions and the stress distributions at the interface. It is generally considered that these differences would affect the loosening of the components and the life of the joints.