摘要 |
A prosthetic knee joint of the hinged type which permits rotation of the bones in two planes and has means for attaching the device to the bones as well as coupling means. The attaching means for the tibia is in the form of a flanged sleeve in which a flanged stem element is adapted to be rotatably received. The stem element and the attaching means for the femur are coupled together so that they are permitted to undergo relative rotation in the plane of flexion. The rotation of the stem in the sleeve about the axis of the shaft of the tibia permits rotational movement of the pair of bones in a second (axial) plane. The stem is free to distract from the sleeve while maintaining alignment to insure proper reengagement. Bearing surfaces on the stem and sleeve elements are adapted to engage so that the large forces exerted on the implanted device by reason of the knee's function and mechanics are distributed over the substantial area of the congruent thrust bearing surfaces. Non-hinged knee joints with congruent bearing surfaces which allow flexion and tibial rotation are shown as alternate constructions.
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