This invention provides for a novel orthopedic prosthesis, specifically a
prosthetic tibial component for a prosthetic total knee joint, that
comprises two constructs, one being a metal base construct that engages
the bone and the other being a polyethylene bearing construct that
attaches to the metal base construct and articulates with a femoral
prosthetic component on the opposing side of the joint. The metal base
construct is composed of two different metals, one of which engages the
bone surface and the other of which engages the polyethylene bearing
construct. Each of these metals is selected so that its characteristics
are well suited to its particular function. More particularly, the first
metal (i.e., the one that engages the bone surface) is selected so as to
provide a superior bone-engaging face, while the second metal (i.e., the
one that engages the polyethylene bearing construct) is selected so as to
provide a superior polyethylene-engaging face. By combining the different
material characteristics of two different metals in the metal bone
construct, it is possible to simultaneously form a superior bone-engaging
face and a superior polyethylene-engaging face.