Method and apparatus for implanting a prosthetic device

In an apparatus for preparing a seating surface of prescribed area and contour on the bone of a joint at which a prosthetic device is to be implanted, the bone having been provided with at least a partially prapared site for locating and seating a component part of the prosthetic joint at the seating surface, guide means for guiding a cutter to cut the bone and establish said seating surface, the cutter including a cutting surface and a bearing surface adjacent to the cutting surface, said guide means comprising:

• a contouring guide having opposite ends and an upper loctor surface extending longitudinally along the contouring guide between the opposite ends;
• the upper locator surface having a profile contour essentially matching the contour of the prescribed area of the seating surface;
• and
• holding means integral with the contouring guide for holding the contouring guide on the bone with the upper locator surface placed at a predetermined location relative to the bone above the bone and along the bone such that upon engagement of the bearing surface with the upper locator surface the cutting surface will enter the bone up to a limited depth of cut determined by the predetermined location of the upper locator surface above the bone, and upon longitudinal translation of the bearing surface along the contouring guide, the cutting surface will cut the bone along a limited length of cut determined by the length of the upper locator surface along the bone to prepare the seating surface of prescribed area and contour.

In an apparatus for preparing a seating surface of prescribed area and contour on the bone of a joint at which a prosthetic device is to be implanted, the bone having been provided with at least a partially prepared site for locating and seating a component part of the prosthetic joint at the seating surface, cutting means for cutting the bone to establish said seating surface, the cutting means being guided by a contouring guide having opposite ends and an upper locator surface extending longitudinally along the contouring guide between the opposite ends, the upper locator surface having a profile contour essentially matching the contour of the prescribed area of the seating surface, and holding means integral with the contouring guide for holding the contouring guide on the bone with the upper locator surface placed at a predetermined location relative to the bone above the bone and along the bone, said cutting means comprising:

• a cutter having a cutting surface and a bearing surface adjacent to the cutting surface, the bearing surface being located relative to the cutting surface and the upper locator surface of the contouring guide such that upon engagement of the bearing surface with the upper locator surface the cutting surface will enter the bone up to a limited depth of cut determined by the predetermined location of the upper locator surface above the bone and upon longitudinal translation of the bearing surface along the contouring guide, the cutting surface will cut the bone along a limited length of cut determined by the length of the upper locator surface along the bone to prepare the seating surface of prescribed area and contour.

The method of preparing a seating surface of prescribed area and contour on the bone of a joint at which a prosthetic device is to be implanted, the bone having been provided with at least a partially prepared site for locating and seating a component part of the prosthetic joint at the seating surface, said method comprising the steps of:

• positioning a contouring guide on the bone at said site so as to locate and hold the contouring guide in place over a portion of the bone, with the contouring guide delineating a longitudinal path of travel;
• engaging cutting means with the contouring guide such that cutting portions of the cutting means enter the bone while bearing portions of the cutting means engage the contouring guide;
• and
• translating the cutting means longitudinally along the contouring guide such that the cutting means is confined to the path of travel delineated by the contouring guide and the seating surface is prepared with said prescribed area and contour.