Rod-Through-Plate Fixator for Long Bone Fractures:A Morphological Study on Rabbits

Abstract

We study the effect of a new fixator for treatment of diaphyseal bone fractures of small animal. The experiments  were performed on 12 New Zealand White rabbits. Transverse osteotomy was made in the central  third of the diaphysis of the rabbit’s femur and a rod-through-plate fixator was used to treat the bone fracture.  The regeneration of the bone tissue was studied by means of radiography and histomorphology at  postoperative weeks 2, 4 and 8. The rod-through-plate fixator gives stable fixation and early mobilisation  of the limb. Radiographic images showed that the fractures had repaired well. Morphologically, all the parts  of the callus had a typical structure. An immunohistochemical examination showed elevated levels of extracellular  matrix proteins collagen type II, osteocalcin and osteopontin in the callus area. The new fixation  method gives strong fixation of bone fragments with minimal traumatization of soft tissue during the operation.  The construction of the rod-through-plate fixator allows one to reduce pressure in the area of the  fracture and the dynamic fixation given by intramedullary rods allows micromotions stimulating callus formation  and avoiding implant-induced osteoporosis. The fixator has a simple construction and its use  expands the treatment possibilities for diaphyseal fractures of long bones. The rod-through-plate fixator use  does not require special training for the surgeon.