Patent ID: 8287600

Claim:
A tibial prosthesis for attachment to a tibial bone of a patient, comprising: a tibial stem adapted to be anchored in a cavity in the tibial bone, wherein the tibial stem comprises a socket; a tibial plate comprising a superior surface and an inferior surface, wherein a protuberance sized to fit inside the tibial stem socket extends from the inferior surface of the tibial plate, and wherein the tibial plate and the protuberance define a through-channel axially extending all the way through the superior surface, the inferior surface and the protuberance; and a locking component having a threaded portion, and a head, wherein the locking component is adapted to be inserted through the through-channel in the tibial plate, wherein an internal passage in the protuberance tapers from larger to smaller in a direction moving away from the superior surface of the tibial plate, such that insertion of the locking component through the through-channel in the tibial plate and into the protuberance causes the protuberance to expand radially against an inner surface of the socket of the tibial stem to lock the orientation of the tibial plate relative to the tibial stem.