Offset Resurfacing Head for Ball and Socket Joint

A femoral head resurfacing prosthesis comprising:

• a head having a rim separating an outer surface of the head from an inner surface of the head;
• and
• a stem extending from the inner surface toward an opening of the head defined by the rim,
• wherein a central axis of the head passes through a center of the opening and a pole of the head and the stem has an elongate dimension oriented at an angle in a range from 5 degrees to 20 degrees relative to the central axis of the head, and
• wherein the elongate dimension of the stem is less than 65% of an outer diameter of the head.

A method of implanting a resurfacing implant in a femur of a patient, comprising:

• resecting a first portion of a head of the femur such that a second portion of the head remains;
• retrieving a femoral head implant, the femoral head implant including a head component and a stem component, the head component including a convex outer surface and a concave inner surface and the stem component extending from the concave inner surface to a free end;
• advancing the femoral head implant into the second portion of the head of the femur;
• and
• securing the femoral head implant onto the second portion of the head such that when the concave inner surface contacts the second portion of the head, the stem component lies outside of a tensile stress region of the femur.