Femoral intertrochanteric osteotomy is indicated for severe internal femoral torsion. Correction of femoral torsion may be done at any level of the femur, but the intertrochanteric level offers several advantages. The osteotomy surfaces are broad to enhance stability and rapid union. Angular malunion is less obvious than osteotomies performed in the distal femur.
Perform a rotational profile to document the status of the femur, tibia, and foot. Review an AP radiograph of the pelvis to rule out other problems. Consider the possible need for blood replacement and pre-op antibiotic prophylaxis. Assess the amount of rotational correction needed. In most children, correct idiopathic internal femoral torsion by externally rotating the femur 45°.
Make available interoperative imaging. Prone positioning has several advantages; among them, intraoperative measures of hip rotation are simplified, and gravity aids in exposure. Prep both legs. Drape, allowing the limbs to be freely mobile.
Make a longitudinal lateral skin incision just distal to the greater trochanter. Incise the fascia and reflect the muscles anteriorly. Check position with the C arm to avoid injury to the trochanteric apophysis.
Place two smooth parallel K wires to monitor rotation. Place the pins far enough apart to avoid interfering with the fixation device. Access the alignment and record any differences in rotation between the pins. Use imaging to confirm that the blade-plate guide pin is well-positioned. Make the slot for the blade-plate with a chisel.
The level of the osteotomy is critical. The fixation device should be inserted just distal to the greater trochanteric apophysis. The osteotomy should be low enough to ensure adequate bone for the fixation of the blade but still be proximal enough to be intertrochanteric in location. Make certain the guide pin is positioned before the osteotomy is completed. Check with an image to assure proper level. Complete the transverse osteotomy with a saw.
Insert the blade-plate into the slot and secure. Laterally rotate the leg until the pins show that the femur is 45° more laterally rotated than before the osteotomy. Screw the plate to the shaft, making certain not to lose the desired rotation. Confirm position by imaging and assessing hip rotation.
If fixation is secure, allow mobility in a wheelchair for the first 6 weeks. Allow crutch-walking for 2 additional weeks. Allow return to running at 16 weeks. Remove the plates in 6–12 months.