Abstract: A femoral sizing jig for use in total arthroplasty of left and right knees, comprises a femoral body, an external-rotation-angle arm which is, preferably pivotable, relative to the femoral body for setting an external angular rotation of a left or right femur, at least one of a cutting-jig guide and a cutting jig which is, preferably slidable, relative to the femoral body and in unison with movement of the external rotation-angle arm, and a medial posterior-condylar locator which is movable in unison with the movement of the external-rotation-angle arm, so as to maintain a fixed or substantially fixed relative distance with a medial side of the at least one of a cutting-jig guide and a cutting jig. A posterior-referencing femur resecting system using said femoral sizing jig and a method of resecting a femur at a knee joint relative to the medial posterior condyle are also provided.

Abstract: Leg alignment apparatus for use in total arthroplasty of left and right knees, comprises an intramedullary rod, a femoral body for location on or adjacent to an anterior surface of a femur, and a support element which extends or is extendable from the femoral body to the intramedullary rod for holding the femoral body stationary or substantially stationary relative to the intramedullary rod. A condylar locator which is pivotable relative to the femoral body and which is seatable on a distal end of the femur is also provided, along with a soft-tissue tensioning element to apply a separation between the femur and the tibia, and a varus/valgus indicator to indicate an angular alignment of the knee based on the intramedullary rod and the soft-tissue tensioning element. A method of determining a distal end resection position for a femur at a knee joint is also provided.

Abstract: A femoral sizing jig for use in total arthroplasty of left and right knees, comprises a femoral body, an external-rotation-angle arm which is, preferably pivotable, relative to the femoral body for setting an external angular rotation of a left or right femur, at least one of a cutting-jig guide and a cutting jig which is, preferably slidable, relative to the femoral body and in unison with movement of the external rotation-angle arm, and a medial posterior-condylar locator which is movable in unison with the movement of the external-rotation-angle arm, so as to maintain a fixed or substantially fixed relative distance with a medial side of the at least one of a cutting-jig guide and a cutting jig. A posterior-referencing femur resecting system using said femoral sizing jig and a method of resecting a femur at a knee joint relative to the medial posterior condyle are also provided.