Abstract
To investigate the lubrication condition in knee prostheses under walking conditions, a knee joints simulator is used to simulate the tibial axis load and flexion-extension motion. The fluid film formation in knee prosthesis models is evaluated by measuring the contact electric resistance between a femoral stainless steel component and a tibial conductive elastomeric or polymeric component under constant applied voltage in a knee joint simulator. The effect of swinging motion and the variation of load on the fluid film formation is examined. It is shown that the fluid film formation in a knee joint with an elastomeric tibial component changes, depending on the walking phase, and the film thickness becomes minimum just prior to the toe off during walking motion.
