Abstract: A dental implant comprising an implant body which has an asymmetric root portion receivable in an asymmetric open root cavity of the patient and engagement means on the asymmetric root portion to at least in part engage a surface of the root cavity so as to prevent or inhibit unintentional extraction. The asymmetric root portion is complementarily shaped to fit the said asymmetric open root cavity, thus substantially dispensing with the need for protracted preparation of the root cavity and providing substantially immediate stability for the prosthetic tooth.

Abstract: An alignment guide for use in femoral head surgery. The guide includes a support arm and a cannulated rod supported by, and adjustable with respect to, the support arm. The guide also includes two jaws. The jaws include a superior jaw and an inferior jaw. Each jaw has a proximal end connected to the support arm and a distal end for clamping to the neck of the femur in use. At least one of the jaws is movable from a first open position to a second clamping position. A toothed block is located on the inferior jaw as a biting element on the inferior jaw to improve, in use, the clamping of the jaw with the neck of the femur.

Abstract: The invention relates to an element for incorporation into a prosthetic implant so as to form a bone-contacting portion thereof, the element comprising a rear face, a front face, and a body extending between the rear face and the front face, wherein the front face comprises a basal surface and at least one upstanding portion projecting above the basal surface and having a transverse hole extending therethrough from one side of the upstanding portion to another. It further relates to a prosthetic implant for implantation into a patient so as to contact a bone of the patient, the prosthetic implant comprising a body including a bone-contacting portion for contacting the patient's bone after implantation of the prosthetic implant, wherein the bone-contacting portion is provided with at least one upstanding portion that projects above a surrounding basal surface portion and that is provided with a transverse hole that extends through the upstanding portion from one side to another.

Abstract: A system for use by a surgeon during implantation of a femoral head resurfacing prosthesis in a patient which will locate the correct position for the femoral head resurfacing prosthesis. The system comprises a computer having memory for holding data relating to the size and shape of at least one femoral head resurfacing implant, and data obtained during preoperative scanning of the patient's hip joint.

Abstract: A tibial plate for an endoprosthetic knee is provided, the plate having a proximal face, a distal face and at least one distal posterior reinforcement portion projecting from a posterior region of the distal face, said reinforcement portion having an abutment face bevelled with respect to the distal surface of the tibial plate. A distal anterior posterior reinforcement portion projecting from an anterior region of the distal face may also be included.

Abstract: A surgical drape for use in orthopedic surgery on or at a bone, which drape comprises a sheet sized such that in use it will cover at least a site of an incision in the patient. The drape also comprises an aperture in the sheet, which aperture is movable from a wide position that enables the aperture to pass over the end of the bone, to a narrow position which provides a close fit around the bone.

Abstract: A single-use surgical shaping tool includes a body having a leading end and a drive end. The shaping tool also includes a debris collecting store, at least one cutting means, and at least one means for directing debris into the store.

Abstract: A jig for the application of a femoral head resurfacing prosthesis to a prepared femoral head wherein the jig comprises: at least one support arm having a proximal and a distal end; a jaw located at the distal end of the support arm and angled to the plane of the support arm; a static member located at the proximal end of the or each support arm; an applicator member associated with the static member and movable with respect thereto; and a connector means to enable the applicator member in use to interact with an outer surface of a femoral head resurfacing prosthesis; the applicator member comprising operating means to enable the applicator member to be moved from a first upper position to a second lower position.

Abstract: A replacement ligament prosthesis including an elongate replacement ligament having a femoral end and a tibial end. The prosthesis includes a bar, which in use will extend between the medial and lateral condyles of a femur and across the intercondylar notch, and to which the femoral end of the elongate replacement ligament will be fixed. The prosthesis also includes a fixing means, which in use will fasten the tibial end of the elongate replacement ligament to the tibia.

Abstract: A cap used during the insertion of an acetabular cup prosthesis. The cap comprises an impaction plate having an upperside and an underside. The impaction plate comprises a plurality of separate sectors mutually connected at a connection point on the impaction plate by means of flanges. Each sector includes interlocking means which in use enable the impaction plate to be connected to an introduction tool. The cap also comprises at least one lug extending downwardly from the underside of each sector. The lug is located at the portion of the underside of the impaction plate which will in use enable the lug to be interconnected with a corresponding recess on an internal wall, an external wall or a rim of a prosthesis.

Abstract: A checking jig comprising: a body having an aperture therethrough which in use can be placed over a guide wire located in a well in the head of the femur; an arm extending from the body and shaped to extend around the head of the femur; a tip located on the end of the arm remote from the body said tip representing the diameter at which a particular size of sleeve cutter will cut; and means for adjusting the position of the tip between different positions representing different cut diameters.

Abstract: An alignment guide for use in femoral head surgery comprising: a support arm having a proximal and a distal end; a ring located at the distal end of the support arm and angled to the plane of the support arm; and a collar located at the proximal end of the support arm, the support arm being configured such that the axis of the bore of the collar is located above the ring.

Abstract: An alignment guide for use in femoral head surgery comprising: a support member; a cannulated rod supported by, and adjustable with respect to, the support arm, and two jaws, a superior jaw and a inferior jaw, each jaw having a proximal end connected to the support, and a distal end for clamping to the neck of the femur in use; at least one of said jaws being movable from a first open position to a second clamping position.

Abstract: The invention relates to an element for incorporation into a prosthetic implant so as to form a bone-contacting portion thereof, the element comprising a rear face, a front face, and a body extending between the rear face and the front face, wherein the front face comprises a basal surface and at least one upstanding portion projecting above the basal surface and having a transverse hole extending therethrough from one side of the upstanding portion to another. It further relates to a prosthetic implant for implantation into a patient so as to contact a bone of the patient, the prosthetic implant comprising a body including a bone-contacting portion for contacting the patient's bone after implantation of the prosthetic implant, wherein the bone-contacting portion is provided with at least one upstanding portion that projects above a surrounding basal surface portion and that is provided with a transverse hole that extends through the upstanding portion from one side to another.

Abstract: A system is disclosed for use by a surgeon during implantation in a patient of a tibial implant and of a femoral implant in the course of a knee replacement operation. It comprises a navigation computer whose memory is arranged to hold data relating to size and shape of at least one tibial implant and at least one femoral implant as well as data obtained during pre-operative scanning of the patient relating to the tibia and femur of the patient and also data relating to the three dimensional position and orientation of at least one bone selected from the patient's tibia and the patient's femur obtained during the course of the knee replacement operation. It also includes registration means for registering the three dimensional position and orientation of the patient's tibia and/or femur during the course of the knee replacement operation, as well as detector means connected to the computer and operatively coupled to the registration means for detecting the position and orientation of the at least one bone.

Abstract: A knee prosthesis comprises (i) a femoral component having a medial condyle and a lateral condyle and (ii) a tibial component. The rolling surface of the medial condyle is part-spherical and the tibial component has a complementary part-spherical depression in its upper surface to receive the medial condyle. The bearing surface of the lateral condyle includes a posterior part which has a curvature in a substantially sagittal plane about a first point on a transverse axis that passes through the center of curvature of the rolling surface of the medial condyle and an anterior part which has a curvature in the same plane about a point that lies on a second transverse axis parallel to, and anterior to, the first transverse axis. The tibial component has an arcuate groove to receive the lateral condyle and to permit, in flexion of the knee after implantation, limited anterior/posterior movement of the lateral side of the tibia relative to the femur.

Abstract: An artificial acetabulum is described comprising a metal cup having on its outer surface means for locking the cup in a pelvic cavity, a hollow locating peg projecting from the base of the cup and integral therewith, and a liner within the cup and having a projection which fits within the hollow peg.

Abstract: A surgical tool, for use in hip replacement operations comprises a substantially linear stem which in use seats within a preformed femur cavity. A fixed arm extends medially from an upper portion of the stem and terminates in support for a rotatable cutter. One end of the cutter is received in a seating on the stem below the fixed arm. Ancilliary equipment includes a depth locating tool, so correctly positioning the hip implant in relation to the retained femur neck.

Abstract: An endoprosthetic ankle joint device comprises a talar component with a convex articulatory surface having an intermediate part-circular-cylindrical area coaxially flanked at each end by like mutually divergent part-conical areas, and a tibial component with an assymetrical concave articulatory surface complementary with said convex cylindrical area and one of said conical areas. In one form of the device the tibial concave surface has areas complementary with each of the talar conical areas, but to different extents, with the former areas being respectively axially longer and shorter. In another form, the tibial concave surface is only complementary with one of the talar conical areas, and the device comprises a fibular component for articulation with the other talar conical area.