Abstract: A prosthetic patellar component includes a base and a bearing element that includes first and second femoral engaging surfaces disposed between first and second (superior/inferior) edge surfaces The edge surfaces are curved to provide a gradual transition from a posterior facing portion to a nearly vertical superior or inferior facing portion. Moreover, the inferior-superior dimension of the component is at least approximately 90% of the medial-lateral dimension. The relative height and gradually transitioning edges significantly reduce the likelihood of sudden posterior rotation during deep flexion movement. The edge surfaces extend from a substantially posterior facing portion proximate to the first and second femoral engaging surfaces and a substantially vertical facing portion proximate the base.