Patent attributes
A knee prosthesis for total knee replacement has femoral and tibial joint components. The femoral component has a medial condyle, a lateral condyle and an intercondylar recess between the condyles. The condyles in sagittal profile both have spiral outer surfaces, wherein the increasing anterior-to-posterior radii of curvature for the medial condyle is smaller than the corresponding radii of curvature for the lateral condyle. The tibial component has shallow concave medial and lateral condyle surfaces for receiving corresponding condyles of the femoral component as bearing surfaces when the femoral and tibial components are biased together under applied tension by ligaments. Posterior portions of each femoral condyle that contact the corresponding tibial condyle up to 90° flexion are substantially spherical in shape, with gradually increasing radii in coronal profile as flexion increases, while the anterior portions beyond 90° flexion are substantially elliptical in shape in coronal profile.
