Abstract: A metal backing for inclusion in the manufacture of a prosthetic component having a plastic bearing element on an upper surface and has a bottom surface portion with elements for attachment to a bone. The backing has an upper surface portion at least part of which is formed by a grill element having exposed front and rear faces and which is intended to be embedded within the plastic bearing member during construction. The plastic bearing material of the bearing element can be molded so that all the faces thereof exposed to the grill are covered and the grill is embedded within the plastic material of the bearing element. The grill is located on a metal support and is provided with spacers on its front face to space the front face away from the support. The grill is cast integrally into the metal support during manufacture.

Abstract: A metal backing for inclusion in the manufacture of a prosthetic component having a plastic on an upper surface and has a bottom surface portion with elements for attachment to a bone. The backing has an upper surface portion at least part of which is formed by a grill element having exposed front and rear faces and which is intended to be embedded within the plastic bearing member during construction. The plastic bearing material of the bearing element can be molded so that all the faces thereof exposed to the grill are covered and the grill is embedded within the plastic material of the bearing element. The grill is located on a metal support and is provided with spacers on its front face to space the front face away from the support. The grill is cast integrally into the metal support during manufacture. The casting process includes casting a grill on both outer surfaces of the metal backing with the grill element including cross-members spaced from backing surfaces.

Abstract: A prosthetic patello femoral joint assembly comprises a patella mounting component on which is located a movable mobile bearing component. A first side of the bearing component is shaped to engage the patella groove of a natural or an artificial femur. A second side of the mounting component has a substantially spherical convex bearing surface which engages and can articulate against a substantially spherical posterior concave bearing surface on the mounting component. A control means acts between the components to restrict substantially vertical movement of the bearing component about a medio lateral axis of the knee with which it is to be used, but allows substantially horizontal movement and relative rotation between said mounting component and said bearing component.

Abstract: A method of implanting an acetabular cup includes preparing an acetabular socket to receive said cup, placing cement in said socket before or after locating a loading tube in line with the socket and inserting the acetabular cup through the tube into said socket. This is done by pushing it down the tube with an inserter to a predetermined position therein defined by a stop element acting on the inserter or an attachment thereto.

Abstract: An orthopedic instrument for guiding a saw blade for preparing the distal end of a human femur to receive an endoprosthetic femoral component has a base component provided with guide for guiding cutting blades. The guide can be used to shape all of the necessary femoral surfaces to receive the femoral component to be fitted once the base component is fitted to the bone. A device for aligning the base component on the bone elements for attaching the base component to the bone after alignment is also provided.

Abstract: A prosthetic tibial component has a tibial tray having an underside for engaging a prepared tibial plateau. The tibial component has a stem having a tapered connection at one end. The stem has a non-symmetrically shaped bone engagement element extending therefrom. The tray includes a tapered connection element for mating with the tapered connection element on the stem. The tray includes an alignment element for locating and engaging the bone engagement element on the stem to locate the stem at a predetermined position relative to the tibial plateau.

Abstract: A centralizer for the stem of a prosthetic orthopedic implant adapted for implantation into a medullary canal has a hollow annular body portion. The annular body portion has an interior for receiving the stem of the implant. The body portion also includes at least three spring elements extending outwardly from the exterior surface of the body portion. Each spring element has a portion thereof extending generally tangentially with respect to the axial extent of the tapered stem and deformable circumferentially and inwardly towards the stem upon insertion into the medullary canal.

Abstract: A tibial component for a replacement knee prosthesis comprising a tibial tray for connection to a suitably prepared tibia has a tray carrying fixed lateral and medial condylar bearing components. Only the medial component has a shock absorber located beneath it.