| 摘要 |
<p>PURPOSE:To obtain a long life artificial knee joint having a large bending range and versatile properties by specifying the ratio of the radius of curvature to dimension in a forward and rearward direction of the outer surface of the rear part of the condyle of a component on a femur side and forming the stand part fitted with the component on the femur side to the center of the upper surface of a component on a tibia side. CONSTITUTION:A component 4 on a femur side is provided with a front wall part 41, inner and outer condyles 42a, 42b and the projection 44 strongly fixing the component 4 to a bone formed to the inner surface of the almost center of the inner and outer condyles 42a, 42b and the shape of the slide surface (outer surface) is formed into a circular arc state wherein some circular arcs are combined. Further, the ratio R/L of the dimension L of the slide surface in the forward and rearward direction thereof and the radius R of curvature of the outer surface of the rear part of the condyle is set to 0.27-0.33. A component 5 on a tibia side is constituted of an upper plate 6 and the base plate 7 mounted to the under surface (on the side of the tibia 2) thereof and screw parts 8 for fixing the component 5 to the tibia 2 are provided to the under surface of the base plate 7 in a protruding state. By this constitution, a knee joint movable region can be expanded to a large extent up to a state near to a normal knee joint.</p> |
