A prosthetic hip joint comprising: (a) a femoral component including a femoral head; and, (b) an acetabular component including an acetabular cup and an acetabular cup insert, the acetabular cup insert sized to receive the femoral head, where the femoral head is sized to have a spherical center that matches a spherical center of a patient's native femoral head, where the acetabular cup is sized to have a cavity with a spherical center that matches a spherical center of a cavity of a patient's native acetabulum and, where the femoral head center of the femoral component is concentric with the center of the cavity of the acetabular cup.