Changes in the Functional Flexion Axis of the Knee Before and After Total Knee Arthroplasty Using a Navigation System

摘要

Long term satisfaction of patients after total knee arthroplasty (TKA) has lagged behind that of total hip arthroplasty [1]. Reported dissatisfaction for total knee arthroplasty is usually in the 20% range with functional satisfaction being lower [1 ]. One reasonable explanation for the discrepancy between hip and knee outcomes is the relatively simple motion of the hip compared with the knee. The knee joint moves with a combination of rotation and translation of the femur on the tibia (gliding and rolling, where gliding is rotation with the surfaces in contact sliding past one another (like a ball rolling in water) and rolling is rotation with no sliding of the surfaces in contact (like a car tire)) [2]. The primary rotational movement of the knee is flexion/extension in the sagittal plane, but there are also rotations in the transverse and coronal planes during everyday movements. More specifically, even the flexion/ extension movement of the knee can be quite complex with varying combinations of rolling and gliding movements medially and laterally.