Methods for forming prosthetic implants, including femoral implants, are discussed. While the methods can include any suitable step, in some cases, they include providing a master negative mold defining an internal space shaped to form a femoral component configured to replace a distal portion of a femur, wherein the femoral component comprises at least one of: an anterior flange that is disposed at an anterior proximal end of the femoral component, and a proximal extension disposed at a proximal portion of a posterior condyle of the femoral component, the proximal extension comprising a concave articulation surface that is configured to articulate against at least one of: a tibial prosthetic component and a tibia; filling the master negative mold with a molding material to form a molded femoral component; and removing at least one of: the anterior flange, and the proximal extension from the molded femoral component to form a modified molded femoral component. Other implementations are described.