Extracortical bone-bridging fixation with use of cortical allograft and recombinant human osteogenic protein-1.

Background: Prosthetic reconstruction with extracortical bone-bridging fixation is an effective method for the treatment of massive bone loss. We evaluated the effect of the use of recombinant human osteogenic protein-1 (rhOP-1) combined with allogenic cortical bone strips as a substitute for an autogenous bone graft for extracortical bone-bridging.

Methods: Eight skeletally mature adult male dogs underwent a bilateral resection of a 6-cm segment of the femoral diaphysis and reconstruction with a porous segmental prosthesis.

Low-intensity pulsed ultrasound does not enhance distraction callus in a rabbit model.

Low-intensity pulsed ultrasound has been reported to have a positive effect when applied during the consolidation phase of distraction osteogenesis and bone transportation, but the optimal application time has not been determined. We used a rabbit model to determine whether low-intensity pulsed ultrasound applied during the distraction and early consolidation phases of tibial lengthening would have a positive effect on regenerated bone formation. Radiographic analysis showed no differences in regenerated callus area or in percent of callus mineralization between treated and control tibias immediately after distraction or at 1, 2, or 3 weeks after distraction.

Effect of pulsed electromagnetic fields on maturation of regenerate bone in a rabbit limb lengthening model.

To study the effect of applying pulsed electromagnetic fields (PEMF) during the consolidation phase of limb lengthening, a mid-tibial osteotomy was performed in 18 adult New Zealand White rabbits and an external fixator was applied anteromedially. Animals were randomly assigned to treatment and control groups. After a 7-day latency period, the tibiae were distracted 0.

Linear increase in axial stiffness of regenerate callus during limb lengthening.

Distraction osteogenesis is a powerful tool for addressing segmental defects and limb-length discrepancies. Guidelines for the rate and rhythm of distraction have been described. The possibilities of early consolidation or nonunion threaten clinical success.