Lengthening of the Femur with a Remote-Controlled Magnetic Intramedullary Nail: Antegrade Technique.

Abstract

Femoral lengthening with an intramedullary nail avoids the need for external fixation with its inherent challenges. Determine the location of the osteotomy, which should be at the apex of the deformity or at the natural anterior bow of the femur, as well as the length and type of nail, which must be ordered a few weeks in advance. Position the patient supine on a flat radiolucent table; the goal is access for antegrade canal reaming and nail insertion. Begin the osteotomy by making multiple percutaneous drill-holes, thereby avoiding the soft-tissue stripping and heat necrosis associated with the use of a power saw. Use a minimal incision approach to the proximal part of the medullary canal. Ream the medullary canal of the intact bone over a guidewire; mark the rotation before the osteotomy is complete. Insert the internal lengthening nail in an antegrade direction up to the osteotomy location, complete the osteotomy, and pass the nail across the osteotomy site. Insert proximal and distal interlocking screws. To prevent knee stiffness, release the iliotibial band through a 3-cm lateral incision, which is usually made by connecting the two stab wounds created for the distal interlocking screws. Mark the magnet location in the implant on the skin to enable use of the remote control. Postoperative management entails limited weight-bearing, distraction, and range-of-motion exercises. Femoral lengthening with the remote-controlled magnetic intramedullary nail has had excellent clinical efficacy.