A pre-operative joint alignment method comprising: using imaging data of at least a portion of a leg to create a leg model, the leg model including a femur having medial and lateral condyles (216, 218) and a tibia having tibial plateaus that are configured to engage the medial and lateral condyles at a knee joint; displaying an image of the leg model for manipulation by a user; said method being characterized in that it further comprises the steps of: locating a first pivot point within one of the medial or lateral condyles of the leg model, the first pivot point being defined by a center of an arc that approximates a curvature of an outer condylar surface of the leg model wherein the arc extends in a medial-lateral direction and passes through a contact point between a distal end of the condylar surface of the leg model and a proximal end of one of the tibial plateaus of the leg model; wherein the medial or lateral condyle of the leg model containing the first pivot point is a non-arthritic condyle of the leg model, and wherein the other one of the medial or lateral condyles of the leg model is an arthritic condyle of the leg model; locating a second pivot point within the same one of the medial or lateral condyles of the leg model wherein the arc extends in an anterior-posterior direction and passes through a distalmost point on the condylar surface of the leg model; rotating, in the displayed image, the tibia of the leg model with respect to the femur of the leg model, about the first pivot point, to obtain a desired knee joint articulation in a first plane wherein the first plane is a varus-valgus plane; and rotating, in the displayed image, the tibia of the leg model with respect to the femur of the leg model, about the second pivot point, to obtain a desired knee joint articulation in a second plane wherein the second plane is a flexion-extension plane. using imaging data of at least a portion of a leg to create a leg model, the leg model including a femur having medial and lateral condyles (216, 218) and a tibia having tibial plateaus that are configured to engage the medial and lateral condyles at a knee joint; displaying an image of the leg model for manipulation by a user; said method being characterized in that it further comprises the steps of: locating a first pivot point within one of the medial or lateral condyles of the leg model, the first pivot point being defined by a center of an arc that approximates a curvature of an outer condylar surface of the leg model wherein the arc extends in a medial-lateral direction and passes through a contact point between a distal end of the condylar surface of the leg model and a proximal end of one of the tibial plateaus of the leg model; wherein the medial or lateral condyle of the leg model containing the first pivot point is a non-arthritic condyle of the leg model, and wherein the other one of the medial or lateral condyles of the leg model is an arthritic condyle of the leg model; locating a second pivot point within the same one of the medial or lateral condyles of the leg model wherein the arc extends in an anterior-posterior direction and passes through a distalmost point on the condylar surface of the leg model; rotating, in the displayed image, the tibia of the leg model with respect to the femur of the leg model, about the first pivot point, to obtain a desired knee joint articulation in a first plane wherein the first plane is a varus-valgus plane; and rotating, in the displayed image, the tibia of the leg model with respect to the femur of the leg model, about the second pivot point, to obtain a desired knee joint articulation in a second plane wherein the second plane is a flexion-extension plane.