A plurality of knee joint prostheses comprise a first femoral implant and a second femoral implant. The first femoral implant has a first maximum interior anterior to posterior dimension, a first maximum overall exterior anterior to posterior dimension, a first lateral condyle, and a first medial condyle. The second femoral implant has a second maximum interior anterior to posterior dimension that is substantially the same as the first maximum interior anterior to posterior dimension, a second maximum overall exterior anterior to posterior dimension that is different than the first maximum overall exterior anterior to posterior dimension, a second lateral condyle having a medial to lateral dimension that is substantially the same as a medial to lateral dimension of the first lateral condyle, and a second medial condyle having a medial to lateral dimension that is different than a medial to lateral dimension of the first medial condyle.