Challenges in modeling total knee arthroplasty and total hip replacement

Total knee arthroplasty and hip replacement are commonly used procedures in which an ailing knee or hip joint is replaced with a carefully engineered artificial joint. Multibody models of healthy knee and hip joints are used extensively to design artificial knee and joints. The quality of the replacement joint is thus intrinsically related to the quality of the multibody models. In this work, the quality of a kinematic knee model is assessed by comparing predicted knee kinematics to cadaveric knee kinematics under several patellar overstuffing conditions. In addition, the micro motion at the hip joint (between the femoral head and the acetabulum) under varying loads is experimentally measured using a cemented and a cementless cadaveric hip joint.