Apparatus and method for knee implantation

A set of instruments and a surgical technique facilitate precise orientation of the femoral implant. Precision is aided by decoupling the determination of A/P placement, valgus angle, and external rotation into three discrete steps. In this way, a surgeon's full concentration can be directed to each element of placement and fine adjustments can readily be made to each. An Epicondylar Guide is configured to ease referencing external rotation from the epicondyles. The narrow elongated guide is easily alignable with the epicondyles when it is placed on the flat distal cut. A Posterior Reference/Rotation Guide can be attached to the Epicondylar Guide to check the rotation relative to the intact posterior condyles to confirm the epicondylar setting. A slot in the guide guides a saw blade to cut a corresponding slot in the distal femur. An A/P Cutting Guide has a fin that fits in the slot cut in the distal femur. With the A/P Cutting Guide engaging the slot and resting on the flat distal cut, external rotation is fixed and the A/P Cutting Guide can only move in the A/P direction. By moving the guide in the A/P direction, fine adjustments in the flexion and extension gaps can be made. Once A/P placement is set, the anterior and posterior cuts are made through slots in the guide. In an alternative embodiment, the Epicondylar Guide defines a linear track attached to the distal femur and the A/P Cutting Guide includes a slot configured to engage the linear track.