Patent ID: 8002777

Claim:
A punch assembly for use in preparing a tibia bone with a tibia surface for a prosthesis comprising: a static component having a first surface configured to be supported on the tibia surface of the tibia bone and a second surface that is spaced apart from the first surface; a dynamic component that includes a punch having a stem, the dynamic component supported for sliding movement relative to the static component along a generally arcuate path extending between the first and second surfaces of the static component, wherein the static component includes an arcuate support surface that defines the generally arcuate path and includes a third surface that cooperates with the arcuate support surface to define a passage, wherein the third surface generally faces the arcuate support surface of the static component; the third surface is substantially flat, wherein the third surface is substantially parallel and disposed at a distance from an imaginary line that is substantially tangent to the arcuate support surface of the static component; and the dynamic component operable to bypass the static component and to penetrate the tibia surface as the dynamic component travels along the generally arcuate path into the tibia bone to prepare an aperture having an arcuate contour in the tibia bone.