A knee prosthesis in which engagement between the femoral component and the tibial component of the knee prosthesis takes place at a contact area along articular surface areas including complementary medial-lateral surface profile contours having a single medial-lateral articular radius defining an arcuate profile, and anterior-posterior surface profile contours along the femoral component and the tibial component, the anterior-posterior surface profile contour of the femoral component having an essentially constant anterior-posterior articular radius throughout regions of the femoral component which contact the tibial component within a primary range of flexion, the center of the anterior-posterior articular radius being located along a line extending laterally between the medial and lateral attachment points of the collateral ligaments of the knee, such that the contact area along the articular surface areas is maintained at a maximum throughout at least the primary range of flexion for minimizing stresses in the tibial component and better balancing tension in the collateral ligaments during articulation of the knee prosthesis at least within the primary range of flexion, and further including an eminence projecting from the tibial component toward the femoral component, and a follower on the femoral component for engaging the eminence for controlled restraint of the femoral component during a limited portion of the primary range of flexion.