Total knee implant prosthesis assembly and method

A total knee implant prosthesis comprising:

• a tibial component including a pair of bearing surfaces and a post positioned between the bearing surfaces, and wherein the post includes an anterior surface, and
• a femoral component configured to rotate relative to the tibial component, the femoral component including (i) a pair of condyles sized and shaped to articulate on the bearing surfaces and (ii) a cam positioned between the pair of condyles, wherein the cam includes a posterior surface that is convex when the femoral component is viewed in the transverse plane, and
• wherein (i) the cam engages the post at a first contact point when the femoral component is at 0 degrees of flexion, (ii) the cam engages the post at a second contact point located lateral of the first contact point when the femoral component is at a first degree of flexion greater than 0 degrees, and (iii) the cam is disengaged from the post when the femoral component is at a second degree of flexion greater than the first degree of flexion.

A total knee implant prosthesis comprising:

• a tibial component including a pair of bearing surfaces and a post positioned between the bearing surfaces, and wherein the post includes a medial-lateral centerline that defines a medial half of the post and a lateral half of the post, and
• a femoral component configured to rotate relative to the tibial component, the femoral component including (i) a pair of condyles sized and shaped to articulate on the bearing surfaces and (ii) a cam positioned between the pair of condyles, wherein the cam includes a posterior surface that is convex when the femoral component is viewed in the transverse plane, and
• wherein (i) the cam engages the post at a first contact point located on the medial half of the post when the femoral component is at 0 degrees of flexion, (ii) the cam engages the post at a second contact point located on the lateral half of the post when the femoral component is at a first degree of flexion greater than 0 degrees, wherein the cam is disengaged from the medial half of the post when the femoral component is at the first degree of flexion, and (iii) the cam is disengaged from the post when the femoral component is at a second degree of flexion greater than the first degree of flexion.