Cruciate-retaining knee prosthesis

Abstract

Certain embodiments generally provide an improved tibial base member comprising keel portions that allow one or both cruciate ligaments to be preserved. Other embodiments provide improved lateral and/or medial inserts having a mesial lip that helps relieve and or prevent impingement between the femoral component and the tibial eminence. Other embodiments provide improved femoral components having various chamfers to provide additional clearance with respect to the tibial eminence and posterior cruciate ligament without decreasing bone coverage.

1 . A femoral prosthesis, comprising:
 a femoral condylar articulation surface for articulation with a tibial articulation surface;   a medial condyle comprising a first portion of the femoral condylar articulation surface; and   a lateral condyle comprising a second portion of the femoral condylar articulation surface, wherein the medial condyle or the lateral condyle comprise a posterolateral chamfer.   
     
     
         2 . The femoral prosthesis of  claim 1 , wherein the medial condyle comprises the posterolateral chamfer. 
     
     
         3 . The femoral prosthesis of  claim 2 , comprising another chamfer swept around an inner sagittal radius of a posterior portion of the medial condyle or a posterior portion of the lateral condyle. 
     
     
         4 . The femoral prosthesis of  claim 3 , wherein the posterolateral chamfer is combined with the other chamfer. 
     
     
         5 . The femoral prosthesis of  claim 1 , wherein the lateral condyle comprises the posterolateral chamfer. 
     
     
         6 . The femoral prosthesis of  claim 1 , wherein the medial condyle and the lateral condyle comprise the posterolateral chamfer. 
     
     
         7 . The femoral prosthesis of  claim 1 , comprising a patella contacting area, wherein the posterolateral chamfer starts posterior to the patella contacting area. 
     
     
         8 . The femoral prosthesis of  claim 1 , wherein the posterolateral chamfer has an angle between 1 and 10 degrees. 
     
     
         9 . The femoral prosthesis of  claim 1 , wherein the medial condyle extends further distally than the lateral condyle. 
     
     
         10 . The femoral prosthesis of  claim 1 , wherein the medial condyle or the lateral condyle comprise a posteromedial chamfer. 
     
     
         11 . The femoral prosthesis of  claim 1 , comprising an anterior flange with an anterolateral chamfer. 
     
     
         12 . The femoral prosthesis of  claim 1 , comprising at least one chamfer configured to increase clearance with respect to a tibial eminence. 
     
     
         13 . A femoral prosthesis, comprising:
 a femoral condylar articulation surface for articulation with a tibial articulation surface;   a medial condyle comprising a first portion of the femoral condylar articulation surface, wherein the medial condyle comprises a posterolateral chamfer; and   a lateral condyle comprising a second portion of the femoral condylar articulation surface.   
     
     
         14 . The femoral prosthesis of  claim 13 , comprising another chamfer swept around an inner sagittal radius of a posterior portion of the medial condyle or a posterior portion of the lateral condyle. 
     
     
         15 . The femoral prosthesis of  claim 14 , wherein the posterolateral chamfer is combined with the other chamfer. 
     
     
         16 . The femoral prosthesis of  claim 13 , wherein the lateral condyle comprises a posterolateral chamfer. 
     
     
         17 . The femoral prosthesis of  claim 13 , comprising a patella contacting area, wherein the posterolateral chamfer starts posterior to the patella contacting area. 
     
     
         18 . The femoral prosthesis of  claim 13 , wherein the posterolateral chamfer has an angle between 1 and 10 degrees. 
     
     
         19 . The femoral prosthesis of  claim 13 , wherein the medial condyle extends further distally than the lateral condyle. 
     
     
         20 . The femoral prosthesis of  claim 13 , wherein the medial condyle or the lateral condyle comprise a posteromedial chamfer