Abstract: A prosthetic shim and a method for use of prosthetic shims to provide level support and increase the effective thickness of a femoral knee joint component having at least one fixation peg extending from the face which is to seat against the distal end of a femur. The shim is for placement between the femoral component and the femur and comprises a platform having a first surface to cooperatively engage the joint component face and a second surface to engage the distal end of the femur. The shim preferably has a means for securing the shim in place, such as spikes extending from the second surface to be driven into the femur. The platform preferably is shaped and dimensioned to be effective if placed centrally relative to the joint component face, covers a majority of the joint component face, and has an opening corresponding to each peg of the joint component so that the shim can be placed over each peg.

Abstract: This invention provides an improved implantable tibial component comprising an implantable tibial base containing two separate, opposed raised walls which engage oppositely configured recesses in the lower surface of a removable hard polymeric condylar articulating surface insert. The locking mechanism which holds the insert within the base provides a means by which the insert can be locked within the base in a secure fashion. The locking mechanism further provides a means by which the insert can be removed from the implanted tibial base in a simple fashion by raising the anterior end of the insert over the top of the anterior wall on the edge of the tibial base and sliding the insert anteriorly out of the posterior raised walls which also extend along the medial and lateral edges of the tibial base.