Coupled knee prostheses, used as total endoprosthesis, has meniscus bearing and hinge system allowing axial movement and rotation, and lateral stop system, e.g. with plastics disks, to limit angle of rotation of femur relative to tibia

摘要

In coupled knee prosthesis having parts of tibia with upper bearing surface, bearing seat for femur meniscus, allowing rotation about perpendicular axis, femur with sliding surface and hinge through meniscus, connecting femur journal and tibia sleeve, coaxial with tibia meniscus axis of rotation, allowing free rotation and axial movement, (a) meniscus but not sleeve can rotate freely about axis relative to tibia and (b) top of sleeve has lateral stop faces struck by femur (part) to limit angle of rotation relative to tibia. Coupled knee prosthesis has a tibia part with upper bearing surface, on its upper surface, a bearing cup for a femur meniscus part, capable of rotation about an axis perpendicular to the bearing surface, a femur part with a sliding surface, supported in the bearing cup, a hinge connecting the femur part with journal and a sleeve in the tibia part, coaxial with the axis of rotation of the tibia meniscus part, which passes through the meniscus part and allows free rotation and axial movement of the journal. The novel features are that the meniscus part can rotate freely about the axis of rotation relative to the tibia part; the sleeve cannot rotate about the axis of rotation on the tibia part; and the upper end of the sleeve has lateral stop faces struck by the femur part or a part attached to this to limit the angle of rotation of the femur part relative to the tibia part.