An artificial knee joint that compresses both osseous impingement and soft
tissue impingement from occurring and can endure usage over a long period
of time is provided.
The artificial knee joint of the present invention comprises a femoral
component, a tibial tray and an insert plate fixed onto the top surface
of the tibial tray. The femoral component comprises a femoral articular
surface and a cam that is provided on the rear end of the femoral
articular surface and protrudes from the femoral articular surface, the
insert plate comprises a tibial articular surface that makes contact with
the femoral articular surface and a cam-receiving slide surface that
makes contact with the cam. When the knee is extended, the joint takes a
first sliding state in which the femoral articular surface slides against
the tibial articular surface. When the knee is bent at an angle in a
range from 90 to 160 degrees, the joint shifts from the first sliding
state to a second sliding state in which the cam slides on the
cam-receiving slide surface. When the knee is bent deeply with a bending
angle of 180 degrees, the second sliding state is assumed in which a
resection surface of the femoral component and the rear end of the insert
plate are offset.