Bone Transport Using Intramedullary Fixation and a Single Flexible Traction Cable

Abstract

The transfixing wires used in the limb-lengthening and bone-transport procedures described by Ilizarov are the primary source of complications, including infection, restricted joint motion, and pain. In an attempt to eliminate the need for external fixation, a traction cable device was devised to perform a 3-cm bone transport in the canine femur using an interlocking intramedullary rod for fixation. Twelve dogs were divided into 2 groups. Transport began 7 days after osteotomy and continued at either 1 mm per day (n = 6) or 2 mm per day (n = 6). The in vivo peak force, resting force, and stiffness of the transport segment increased throughout distraction to a mean of 150 Newtons, 58 N, and 58 N per millimeter, respectively, at the time of docking. The regenerate and docking sites united in 10 of 12 dogs. Failure of the regenerate associated with deep infection around the rod occurred in 2 animals (17%). Modifications of this technique to reduce the risk of infection are discussed. This study confirms that intramedullary fixation is compatible with distraction osteogenesis and shows that a single traction cable can provide the force necessary for bone transport without transfixing wires in this setting.