Deep flexion knee prosthesis

A femoral knee prosthesis comprising a lateral and a medial condylar element, and an intermediate portion joining said condylar elements, said condylar elements and said intermediate portion having interior surfaces and exterior surfaces, said exterior surfaces of the posterior aspect of said condylar elements extending proximally more than 140° relative to the longitudinal axis of a femur for which a said prosthesis is intended, and the interior surfaces of said posterior portion of said condylar element being substantially planar, and converging proximally toward said longitudinal axis;

• said intermediate portion being located between the anterior portions of said condylar elements, and having an interior surface in two portions that meet along a crest substantially parallel to, or proximally divergent from, said interior posterior surfaces of said condylar elements, said two portions of the anterior interior surface of said intermediate portion each being planar, and extending from said crest to the lateral or medial edge respectively of the adjacent anterior portion of a said condylar element.