Patient specific femoral prosthesis

An orthopaedic implant system comprising:

• a first femoral prosthesis and a second femoral prosthesis each defining a medial side and a lateral side opposite the medial side along a medial-lateral direction, and an anterior side and a posterior side opposite the anterior side along an anterior-posterior direction, each of the first and second femoral prostheses including:
• a core that includes:
• i) a core body elongate along a core body axis, the core body defining an outer core body surface;
• and
• ii) a neck monolithic with the core body, wherein the neck extends out with respect to the core body along a central neck axis,
• wherein the core of the first femoral prosthesis is substantially identical to the core of the second femoral prosthesis;
• and
• a porous casing that encases at least a portion of the core body, the porous casing defining an inner casing surface that extends along the outer core body surface, and an outer casing surface that is opposite the inner casing surface,
• wherein the outer casing surface defines a central outer casing axis,
• wherein each of the first femoral prosthesis and the second femoral prosthesis includes a geometry that includes at least one of a selectable neck angle defined by the central neck axis and the central outer casing axis, a neck offset that extends from the neck to the casing along the central neck axis, and a rotational position of the core body relative to the outer casing surface about an axis that substantially perpendicular to each of the anterior-posterior direction and the medial-lateral direction,
• wherein the geometry of the first femoral prosthesis is different than the geometry of the second femoral prosthesis, and
• wherein the rotational position of the core body relative to the outer casing surface varies a thickness of each of an anterior casing side of the casing and a posterior casing side of the casing that is opposite the anterior casing side.

An orthopaedic implant system comprising:

• a first femoral prosthesis and a second femoral prosthesis each defining a medial side and a lateral side opposite the medial side along a medial-lateral direction, and an anterior side and a posterior side opposite the anterior side along an anterior-posterior direction, each of the first and second femoral prostheses including:
• a core that includes:
• i) a core body elongate along a core body axis, the core body defining an outer core body surface;
• and
• ii) a neck monolithic with the core body, wherein the neck extends out with respect to the core body along a central neck axis,
• wherein the core of the first femoral prosthesis is substantially identical to the core of the second femoral prosthesis;
• and
• a porous casing that encases at least a portion of the core body, the porous casing defining an inner casing surface that extends along the outer core body surface, and an outer casing surface that is opposite the inner casing surface,
• wherein the outer casing surface defines a central outer casing axis,
• wherein each of the first femoral prosthesis and the second femoral prosthesis includes a geometry that includes at least one of a selectable neck angle defined by the central neck axis and the central outer casing axis, a neck offset that extends from the neck to the casing along the central neck axis, and a rotational position of the core body relative to the outer casing surface about an axis that substantially perpendicular to each of the anterior-posterior direction and the medial-lateral direction,
• wherein the geometry of the first femoral prosthesis is different than the geometry of the second femoral prosthesis,
• wherein the inner casing surface extends along a central inner casing axis that is substantially coincident with the core body axis, and the porous casing defines a thickness from the inner casing surface to the outer casing surface, and
• wherein the selectable neck angle causes 1) the thickness at a first side of the porous casing to increase as the casing extends in a distal direction from a proximal core body end of the core body to a distal end of the core body, and 2) the thickness at a second side of the porous casing to decrease as the casing extends in the distal direction, the second side being opposite the first side.