Abstract
Rapid aging of society has aroused a great interest in the disorder that affects the function of knee. Painful and crippling knee conditions are completely released by total knee arthroplasty (TKA). However, wear of polyethylene insert frequently shortens the life span of TKA. Since knee movement involves a complicated combination of translations and rotations, adequate motion analysis is necessary for estimating the wear of inserts and improving the design of artificial knee joint. In this study, we developed the 6-DOF motion simulator for artificial knee joints and analysed the motion of the polyethylene insert on the mobile bearing TKA. Polyethylene insert and tibial component were mounted on the parallel link 6-DOF actuator that can control internal/external and abduction/adduction, and lateral/medial and anterior/posterior translation. Flexion/extension rotation and axial load were controlled by a couple of air survo cylinders. The internal/external motion of the polyethylene insert was observed depending on the flexion/extension motion conditions. The frequency of walking cycle greatly influenced on the motion of insert, which would be induced by the friction between the polyethylene and tibial component.
