Benoist Girard Sas

Howmedica Osteonics Corporation

Howmedica International Inc.

Neil Rushton

Richard Eddy Field

John Andrew Storer

Arnaud AuxEpaules

Richard E Field

Aude Hibon

Peter Nuijten

An inserter for locating and impacting an acetabular cup which has an inner bearing surface in a prepared acetabulum. The inserter has a handle carrying an anvil, an impaction head adapted to receive the cup and a retention system for attaching the cup to the inserter. The retention system extends between an actuator in the handle and the impaction head. The actuator is operable to free the retention system from the cup by impacting the anvil.

Inserter for locating and impacting an acetabular cup

The present invention is intended to provide a cementless prosthetic bearing element which has been molded and which is possible to place in an acetabular socket without cement, the outer surface of the backing being provided with elements to assist stabilization and the ingrowth of bone. Thus, the bearing element is cheaper and easier to produce and provides superior location and installation in the bone. According to the present invention a cementless prosthetic bearing element comprises a backing which supports a bearing liner having a bearing surface, the backing being molded from a rigid polymeric material and said bearing liner being made from elastomeric polyurethane material to which the backing is molded with an outer surface which includes a number of raised engagement features provided in directions extending away from and/or towards the outer periphery of the outer surface.

Cementless prosthetic bearing element

A prosthetic femoral component is located in a prepared socket in a femur which has been resected at a position on the proximal side of its neck. The component includes an insert portion and an enlarged proximal head portion the distal end of the head portion being adapted for location in the prepared socket. The component takes advantage of the bone at the periphery of the socket which enables the insert and the part of the head concerned to be accurately and firmly located in the bone. The presence of the bone at the outer edges of the socket helps to stabilize the component. The insert portion can be dimensioned to pass through the neck of the femur with which it is to be used or to be shorter depending upon the requirements.

Femoral hip prosthesis

A prosthetic femoral component is located in a prepared socket in a femur which has been resected at a position on the proximal side of its neck and Includes a tapered insert and a proximal head portion. The proximal end of the insert portion is adapted for location in the prepared socket and has a maximum dimension in a plane normal to the distal-proximal axis of the neck which is larger than the minimum dimension of the neck in a parallel plane. The component takes advantage of the bone at the periphery of the socket which enables the insert to be accurately and firmly located in the bone. The presence of the bone at the outer edges of the socket helps to stabilize the component. Preferably the tapered insert portion is flared outwardly in the proximal direction. The tapered insert portion can be dimensioned to pass through the neck of the femur with which it is to be used or it can stop short of it.

An acetabular cup for a total hip prosthesis has an outer shell and an inner bearing component. The shell is molded around the inner bearing component and has an elastic modulus similar to subchondral bone of between 5 GPa and 18 GPa. The shell has a part-spherical main portion and two independent arms projecting from the part-spherical main portion. The arms are separated from each other by an opening of predetermined shape and size.

Growing community of inventors

Cambridge, United Kingdom

Neil Rushton