KNEE PROSTHESIS WITH GUIDED EXTENSION AND FLEXION

摘要

An orthopaedic knee joint prosthesis (10) provides guided motion in a wide range of motion, and in both extension and flexion. In flexion, a tibial bearing component (16) shifts to a first position in which a posterior cam (36) formed in a femoral component (12) engages a tibial spine (18) coupled to a tibial component (14). Contact between the posterior cam and the spine guides the motion profile of the knee joint prosthesis throughout a wide range of flexion movement. In extension, the bearing component shifts to a second position in which an anterior cam (34) formed in the femoral component engages the spine. Contact between the anterior cam and spine guides the motion profile of the knee joint prosthesis throughout a wide range of extension. The anterior and posterior cams, mobile bearing component, and tibial component -mounted spine cooperate to facilitate guided flexion and extension of the knee joint prosthesis throughout a wide range of motion.