Fig 2.

Anteroposterior left knee radiograph with preoperative templating for biplanar lateral opening wedge distal femoral osteotomy. The 4° correction is calculated using the hip knee ankle angle and transposed to the desired cut at the distal femur starting 2 cm above the lateral flare (white arrow) and aiming toward the adductor tubercle while preserving a 1-cm medial hinge (asterisks). The amount of correction is measured at the lateral cortex; in this case, 6 mm (black line).