Femoral prostheses with upsizing and downsizing capabilities
According to one example, a femoral prosthesis system is provided that has a plurality of sizing options using two families of femoral prostheses is disclosed. The second family of femoral prostheses can have a predetermined increase in femoral posterior condylar offset relative to the first family of femoral prosthesis. In one example, the second family of femoral prostheses can have the predetermined increase in the femoral posterior condylar offset while maintaining substantially a same femoral medial-lateral condylar extent relative to a comparably sized one of the first family of femoral prostheses.
1 . A system for knee arthroplasty comprising:
a family of femoral components having a plurality of different stock sizes, wherein at least two of the plurality of different stock sizes have a same first dimension but differ in at least a second dimension, each of the family of femoral components including a medial condyle and a lateral condyle; and
a family of tibial bearing components having a plurality of different stock sizes, each of the tibial bearing components having an articular surface, the articular surface including a medial compartment and a lateral compartment;
wherein at least two of the plurality of different stock sizes of the family of femoral components are compatible for articulation with two of the plurality of different stock sizes of the family of tibial bearing components and a plurality of different stock sizes of a family of tibial components;
wherein the same first dimension comprises a femoral medial-lateral condylar extent as measured from a medial most edge of the medial condyle to a lateral most edge of the lateral condyle;
wherein the at least the second dimension comprises a posterior condylar offset as measured from an axis of a stem housing to a first posterior-most point of one or more of the medial condyle and the lateral condyle.
2 . The system of claim 1 , wherein at least one of a posterior condylar offset as measured from an axis of a stem housing to a first posterior-most point of one or more of the medial condyle and the lateral condyle or a femoral medial-lateral condylar extent as measured from a medial most edge of the medial condyle to a lateral most edge of the lateral condyle for at least two of the plurality of different stock sizes for the family of femoral components differs by a predetermined amount.
3 . The system of claim 1 , wherein a two smallest of the plurality of different stock sizes of the family of femoral prostheses and a two smallest of the plurality of different stock sizes of the family of tibial components are compatible with a same stock size of the family of tibial bearing components.
4 . The system of claim 1 , wherein at least four of the plurality of different stock sizes of the family of femoral components and at least six of the plurality of different stock sizes of the family of tibial components are compatible with three of the plurality of different stock sizes of the family of tibial bearing components.
5 . The system of claim 1 , wherein each the plurality of different stock sizes of the family of femoral components is compatible for articulation with at least two of the plurality of different stock sizes of the family of tibial bearing components.
6 . The system of claim 1 , wherein eight of the plurality of different stock sizes of the family of femoral components are compatible for articulation with six of the plurality of different stock sizes of the family of tibial bearing components.
7 . The system of claim 1 , wherein three out of at least eleven of the plurality of different stock sizes of the family of tibial bearing components are compatible with no more than two of the plurality of different stock sizes of the family of femoral components.
8 . The system of claim 1 , wherein, for the family of femoral components, at least six pairs of the plurality of different stock sizes have the same first dimension.
9 . They system of claim 1 , wherein at least a majority of the plurality of different stock sizes of the family of femoral components differ by a predetermined same amount with respect to at least the second dimension as compared with a next larger or next smaller stock size of the plurality of different stock sizes for the family of femoral components.
10 . A system for knee arthroplasty comprising:
a family of femoral components having a plurality of different stock sizes, each of the femoral components including a medial condyle and a lateral condyle; and
a family of tibial bearing components having a plurality of different stock sizes, each of the tibial bearing components having an articular surface including a medial compartment and a lateral compartment configured for articulation with the medial condyle and the lateral condyle of at least one of the family of femoral components, respectively;
wherein each the plurality of different stock sizes of the family of femoral components is compatible for articulation with at least two of the plurality of different stock sizes of the family of tibial bearing components;
and wherein three out of at least eleven of the plurality of different stock sizes of the family of tibial bearing components are compatible with no more than two of the plurality of different stock sizes of the family of femoral components.
11 . The system of claim 10 , wherein at least two of the plurality of different stock sizes of the family of femoral components have a same first dimension but differ in at least a second dimension.
12 . The system of claim 10 , wherein a two smallest of the plurality of different stock sizes of the family of femoral prostheses and a two smallest different stock sizes of a family of tibial components are compatible with a same stock size of the family of tibial bearing components.
13 . The system of claim 10 , wherein at least four of the plurality of different stock sizes of the family of femoral components and at least six different stock sizes of a family of tibial components are compatible with three of the plurality of different stock sizes of the family of tibial bearing components.
14 . The system of claim 10 , wherein eight of the plurality of different stock sizes of the family of femoral components are compatible for articulation with six of the plurality of different stock sizes of the family of tibial bearing components.
15 . The system of claim 10 , wherein at least a majority of the plurality of different stock sizes of the family of femoral prostheses differ by a predetermined same amount with respect to at least a second dimension as compared with a next larger or next smaller stock size of the plurality of different stock sizes of the family of femoral prostheses.