Patent ID: 7101401

Claim:
A tibial component of a knee-joint endoprosthesis, the tibial component comprising a flat tibial bearing surface, a bearing body that is slidably seated thereon and comprises two concave bearing dishes in which a femoral component can be movably seated, and a rotational guide that guides the rotation of the bearing body on the tibial bearing surface about an axis perpendicular thereto, wherein the guide comprises a bearing post in the form of a regular cylinder that stands upright on the tibial bearing surface and terminates at a free end, the guide further comprising first and second elongate post projections extending radially outward from the cylinder, the guide comprising a cylindrical section above the post projections, the post projections being spaced from the free end of the cylinder by a first distance, the post projections also being spaced above the tibial bearing surface by a first height, wherein the first and second post projections comprise longitudinal axes lying along a single line which is substantially parallel to an anterior-posterior axis, the guide configured to be inserted into a post receptacle on a slide face on a side of the bearing body facing the tibial bearing surface, the post receptacle further comprising a recess or groove corresponding to a height of the post projections, the post receptacle having an elongate opening sized to receive the guide and post projections, the opening having a longitudinal axis along a major axis of the opening transverse to a minor axis of the opening, wherein the longitudinal axis of the opening lies at a non-zero angle with respect to both an anterior-posterior axis and a medial-lateral axis of the bearing body.