Supracondylar rotation osteotomy of the femur influences the coronal alignment of the ankle.

Supracondylar external rotation osteotomy of the femur leads to lateralization of the weight bearing line at the knee and ankle due to valgisation of the coronal limb alignment. The mobile subtalar joint has to compensate (inversion) for the resulting valgus orientation of the ankle to ensure contact between the foot and the floor. When planning a rotational osteotomy of the lower limb, this should be appreciated - especially in patients with a preexisting valgus alignment of the lower extremities or restricted mobility in the subtalar joint.