Bone resection apparatus and method for knee surgery

A system comprising:

• an implant system including a femoral component having a femoral component thickness and a tibial component having a tibial component thickness, the implant system having an overall implant thickness which is the sum of the femoral component thickness, the tibial component thickness;
• and an additional joint laxity distance corresponding to a desired amount of joint laxity;
• at least one spacer having a body including a planar seating surface, an arcuate condylar surface arching away from the seating surface generally in the shape of an anatomic femoral condyle, and an elongated support having a longitudinal axis, the spacer having a spacer thickness normal to the planar seating surface;
• and
• a tibial cut guide including an aperture having a longitudinal axis, the aperture configured to engage the cut guide support for linear translation of the cut guide parallel to the aperture longitudinal axis, a cutter guide slot defining a cut plane oriented parallel to the aperture longitudinal axis, the cut plane being spaced a predetermined distance from the aperture such that in an assembled configuration the cut plane is spaced from the arcuate condylar surface by a tibial resection distance.

A method of performing knee surgery comprising:

• resecting a portion of a distal femoral bone;
• inserting a spacer into the knee joint to abut a cut surface of the distal femoral bone, the spacer having an arcuate condylar portion facing away from the cut surface;
• abutting the arcuate condylar portion with a surface of a proximal tibial bone:
• mounting a tibial cut guide on the spacer to position a cut plane at a predetermined posterior slope angle and at a depth relative to the cut surface of the distal femoral bone;
• and
• guiding a cutter in the cut plane to form a planar surface on the proximal tibial bone.