Acetabular cup prosthesis with extension for deficient acetabulum

An acetabular cup prosthesis for use in deficient acetabulae, the prosthesis comprising;

• a body portion having an axis and a rim, the rim tangent to a base plane that is perpendicular to the body portion's axis;
• an extension comprising a top surface and a bottom surface;
• wherein the body portion and the extension are connected by a connecting means;
• whereby the extension has a first angle, the first angle being formed between the base plane and a first line, the first line having a first point at the intersection of the extension with the body portion and a second point at the opposite end of the extension, with both the first and the second point located in the middle of the extension's bottom surface;
• and
• so that the extension has a second angle that is perpendicular to the first angle, the second angle being formed between the first line and a plane containing the body portion axis and the first point;
• and
• wherein one or more components of the prosthesis includes a shape memory alloy.

An acetabular cup prosthesis for use in deficient acetabulae, the prosthesis comprising:

• a cup-shaped body portion having a central axis, an inner surface, an outer surface, and a rim tangent to a base plane;
• an extension, the extension comprising mechanical means for connecting to the body portion;
• a liner, the liner being insertable into the body portion and comprising a lip that rests substantially on the body-portion's rim;
• the liner and the body portion farther comprising a connecting means whereby they may be connected;
• and
• wherein one or more components of the prosthesis includes a shape memory alloy.

A modular acetabular cup prosthesis system for use in deficient acetabulae, the system comprising;

• a selection of cup-shaped body portion units, each cup-shaped body portion unit having a central axis, an inner surface, an outer surface, and a rim tangent to a base plane;
• a selection of extension units, each extension unit comprising mechanical means for connecting to a body portion unit;
• a selection of liner units, each liner unit being insertable into a body portion unit and comprising a substantially concave inner surface, a substantially convex outer surface, and a lip that rests substantially on the body-portion unit's rim;
• each liner unit and body portion unit further comprising a connecting means whereby they may be connected;
• whereby the extension has a first angle, the first angle being formed between the base plane and a first line, the first line having a first point at the intersection of the extension with the body portion and a second point at the opposite end of the extension, with both the first and the second point located in the middle of the extension's bottom surface;
• so that the extension has a second angle that is perpendicular to the first angle, the second angle being formed between the first line and a plane containing the body portion axis and the first point;
• wherein the first angle has an absolute value in the range of 15 to 120 degrees and the second angle has an absolute value in the range of 0 to 180 degrees;
• whereby the system enables rapid and economical assembly of an optimally-shaped acetabular cup prosthesis by choosing a liner unit, a body portion unit, and an extension unit;
• and
• wherein one or more components of the prosthesis includes a shape memory alloy.

A method of sizing and implanting an acetabular cup prosthesis in a patient, the method comprising;

• attaching at least one extension to a cup-shaped portion of an acetabular prosthesis, the cup-shaped portion comprising an inner surface with a central axis, an outer surface, and a rim;
• implanting the prosthesis in the patient;
• wherein the extension is configured to contact the outer surface of the cup-shaped portion of the prosthesis and extends away from its axis;
• and
• wherein one or more components of the prosthesis includes a shape memory alloy.

A method of implanting an acetabular cup prosthesis in a patient, the method comprising;

• attaching at least one extension to a cup-shaped portion of an acetabular prosthesis, the cup-shaped portion comprising an inner surface with a central axis, an outer surface, and a rim;
• cutting the bone to achieve a geometry suitable for accommodating said extension;
• implanting the extension in the patient;
• wherein the extension contacts the outer surface of the cup-shaped portion of the prosthesis and extends away from its axis;
• and
• wherein one or more components of the prosthesis includes a shape memory alloy.