Patent ID: 7678152
Filing Date: 2010-03-16
Classification: A61F

Abstract:
1. An artificial knee joint comprising: a femoral component adapted to be attached to a distal end of a femur, and a tibial component adapted to be attached to a proximal end of a tibia, said tibial component supporting a medial condyle and a lateral condyle of said femoral component by a medial articular surface and a lateral articular surface of said tibial component so that said femoral component and said tibial component are in relation of making rotation; wherein said tibial component is provided with a post that has an outwardly curving posterior surface in such a manner that a lateral articular surface side of said posterior surface of said post is set back from a medial auricular surface side thereof so that a center of said curving posterior surface is turned outwardly to said lateral condyle side and in such a manner that said post is formed into substantially a triangular shape when viewed form above by reducing a thickness of side surfaces from the side surfaces toward an anterior surface, said post being disposed approximately in a longitudinal center between said two articular surfaces so that said post is inside an intercondylar groove which is formed between said medial condyle and said lateral condyle and said intercondylar groove extends from a posterior end to near an anterior end of said femoral component, said intercondylar groove being comprised of a lateral surface and a medial surface so that said lateral surface is parallel to a longitudinal direction of said tibial component, and said medial surface is parallel to the longitudinal direction from posterior end to substantially a center in the longitudinal direction and then from the center towards the anterior end gradually curves and comes closer to said lateral condyle side such that the intercondylar groove extends towards the lateral condyle side; said femoral component is provided with a cam that is disposed at a posterior portion of said intercondylar groove and a surface of said cam in a lengthwise direction comes into direct contact with said curving posterior surface of said post when said rotation proceeds, said cam being-provided horizontally in said intercondylar groove and in a drum shape with an outer lateral side diameter of said cam being larger than an inner medial side diameter thereof; and said post and said cam are provided so that said femoral component is turned outwardly with respect to said tibial component when said rotation proceeds.