All osteotomies were planned using a landmark based deformity analysis [6 (link), 7 (link)]. In axial CT images, the orientation of the femoral neck was measured against a horizontal line on the computer screen. Then the posterior condylar line at the distal femur was measured against the horizontal line. The two angles had to be either added (when oriented in different directions) or subtracted (when oriented in the same direction) to generate a value for femoral torsion.
Surgeries were performed by three experienced surgeons in a standardized manner. The patient was positioned supine. Two Schanz screws were positioned, one proximal and one distal to the osteotomy level. They were inserted in angulation to each other in the amount of the planned correction angle. A medial subvastus approach was established as described earlier [3 (link), 8 (link)]. Supracondylar monoplane osteotomy was performed and a TomoFix MDF plate (DePuy Synthes, Solothurn, Switzerland) was used for fixation [9 (link)].
Surgeries were performed by three experienced surgeons in a standardized manner. The patient was positioned supine. Two Schanz screws were positioned, one proximal and one distal to the osteotomy level. They were inserted in angulation to each other in the amount of the planned correction angle. A medial subvastus approach was established as described earlier [3 (link), 8 (link)]. Supracondylar monoplane osteotomy was performed and a TomoFix MDF plate (DePuy Synthes, Solothurn, Switzerland) was used for fixation [9 (link)].