Motorized internal lengthening of long bones: residual limb lengthening

Distraction osteogenesis can be performed for transfemoral amputees using a motorized intramedullary limb lengthening nail (LLN) such as the 14×130 mm NuVasive Freedom nail. Despite being the shortest commercially available LLN, some patients have even shorter residual femurs, making it impossible to link the bone to the nail by the standard technique of inserting a cross-locking bolt through the proximal and distal nail holes. Two modified techniques of linking a very short femur to a LLN are introduced in this manuscript. The triple cable lasso technique passes 2 cerclage cables transversely through the cortex and then the nail hole, with a third cable clamping the first 2 to the outer cortex. The contoured locking plate technique bends a locking plate to fit over the protruding distal tip of the nail, locks a screw in the plate which threads the distal nail hole, and then locks the plate to the bone with unicortical screws.