Prosthetic knee tibial component constructed of synthetic polymeric material

A tibial component constructed of a unitary member of synthetic polymeric material for use in a prosthetic knee implant including a femoral component having condylar elements, the tibial component including a bearing portion having an upper surface for confronting the femoral component and a lower surface for engaging the proximal tibia, the tibial component comprising:

• condylar bearing surface portions along the upper surface of the bearing portion for engaging the condylar elements of the femoral component and accepting the load imposed by the condylar elements of the femoral component during service;
• and
• a keel projecting in an axial direction downwardly from a proximal end at the lower surface of the bearing portion to a distal end spaced away from the lower surface, the keel including a pair of flanges extending in the axial direction and establishing a generally V-shaped overall cross-sectional configuration in planes transverse to the axial direction, the V-shaped cross-sectional configuration having an apex located essentially centrally of the bearing portion along the medial-lateral direction;
• the flanges each having an inner edge located adjacent the apex, and an outer edge spaced away from the apex in a medial-lateral direction and extending in a posterior direction from the inner edge toward the outer edge such that the flanges make an angle with one another so as to be placed beneath the bearing surface portions and being tapered axially such that the outer edges extend generally from the lower surface of the bearing portion at the proximal end of the keel to the apex at the distal end of the keel to establish gussets for reinforcing the bearing portion against the load imposed by the condylar elements of the femoral component and stabilizing the keel during service.