Hip prostheses

A bipolar prosthesis, comprising:

• a. a shell which includes an outer surface for bearing against acetabular tissue and a cavity;
• b. a multi-material liner adapted to fit within the shell cavity, the liner containing a liner cavity adapted to receive the head of a femoral component;
• c. a locking ring adapted to fit within the shell cavity in order to retain the head of the femoral component within the liner cavity;
• d. wherein the multi-material liner includes a first portion of polyethylene which has been treated to improve its crosslinking and wear resistance properties and a second portion that remains untreated.

A process for installing a prosthesis in a patient, comprising:

• 1. Providing a prosthetic component, comprising:
• a. a shell which includes an outer surface adapted to cooperate with acetabular tissue and a cavity;
• b. a multi-material polyethylene liner adapted to fit within the shell cavity, the liner containing an inner cavity adapted to receive a head of a femoral component;
• c. at least one location on the inner cavity of the liner treated to a greater degree than other locations on the inner cavity of the liner to increase crosslinking of the polyethylene in said at least one location and at least one location that remains untreated;
• 2. preparing the patient's acetabulum;
• 3. installing the prosthetic component in the patient's acetabulum;
• 4. installing a femoral stem in the patient's femur;
• and
• 5. coupling the femoral stem with the prosthetic component.

A process for installing a bipolar prosthesis in a patient, comprising:

• 1. providing a bipolar prosthetic component, comprising:
• a. a shell which includes an outer surface for bearing against acetabular tissue and a cavity;
• b. a liner adapted to fit within the shell cavity, the liner containing a liner cavity adapted to receive a head of a femoral component;
• c. a locking ring adapted to fit within the shell cavity in order to retain the head of the femoral component within the liner cavity;
• d. wherein the liner includes a first portion of polyethylene which has been treated to improve its crosslinking and wear resistance properties, and the locking ring includes a portion of polyethylene which has not been treated in said manner, said portion of the locking ring thereby featuring greater strength properties than said treated portion of the liner;
• 2. preparing the patient's acetabulum;
• 3. installing the prosthetic component in the patient's acetabulum;
• 4. installing a femoral stem in the patient's femur;
• and
• 5. coupling the femoral stem with the prosthetic component.