A prosthetic implant is disclosed comprising: a first component comprising a first inner surface and a first outer surface, a second component comprising a second outer surface adapted to contact and engage with the first inner surface, the second component further comprising a second inner surface, a third component comprising a third outer surface adapted to contact and engage with the second inner surface, the third component further comprising a third inner surface, and a fourth component comprising a fourth outer surface adapted to contact and engage with the third inner surface; wherein the second component is rotatable relative to the first component about a first axis, the third component is rotatable relative to the second component about a second axis perpendicular to the first axis, and the fourth component is rotatable relative to the third component about a third axis perpendicular to the first axis and second axis; the first inner surface and the second outer surface are each formed with a first partial cylindrical shape, the first inner surface and the second outer surface each comprise a flat surface normal to the first axis and are engageable with one another such that the second component is rotatable relative to the first component about the first axis only, the second inner surface and the third outer surface are each formed with a second partial cylindrical shape, the second inner surface and the third outer surface each comprise a flat surface normal to the second axis and are engageable with one another such that the third component is rotatable relative to the second component about the second axis only, and the third inner surface and the fourth outer surface are each formed with a third partial cylindrical shape, the third inner surface and the fourth outer surface each comprise a flat surface normal to the third axis and are engageable with one another such that the fourth component is rotatable relative to the third component about the third axis only.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

An acetabular hip implant and method includes an acetabular shell component having a first feature and a first insert having a second feature that cooperates with the first feature of the acetabular shell component and further includes a third feature. The implant further includes a second insert having a fourth feature that cooperates with the third feature of the first insert and further includes a fifth feature. A femoral head component includes a sixth feature that cooperates with the fifth feature. Interaction between the first and second features, between the third and fourth features, and between the fifth and sixth features mechanically constrains the acetabular hip implant to prevent dislocation of the femoral head during rotation.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

An acetabular hip implant and method includes an acetabular shell component having a first feature and a first insert having a second feature that cooperates with the first feature of the acetabular shell component and further includes a third feature. The implant further includes a second insert having a fourth feature that cooperates with the third feature of the first insert and further includes a fifth feature. A femoral head component includes a sixth feature that cooperates with the fifth feature. Interaction between the first and second features, between the third and fourth features, and between the fifth and sixth features mechanically constrains the acetabular hip implant to prevent dislocation of the femoral head during rotation.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

An acetabular hip implant and method includes an acetabular shell component having a first feature and a first insert having a second feature that cooperates with the first feature of the acetabular shell component and further includes a third feature. The implant further includes a second insert having a fourth feature that cooperates with the third feature of the first insert and further includes a fifth feature. A femoral head component includes a sixth feature that cooperates with the fifth feature. Interaction between the first and second features, between the third and fourth features, and between the fifth and sixth features mechanically constrains the acetabular hip implant to prevent dislocation of the femoral head during rotation.

This invention is directed to orthopedic implants and systems. The invention also relates to methods of implant design, manufacture, modeling and implantation as well as to surgical tools and kits used therewith. The implants are designed by analyzing the articular surface to be corrected and creating a device with an anatomic or near anatomic fit; or selecting a pre-designed implant having characteristics that give the implant the best fit to the existing defect.