BONE HEALING AND MINERILIZATION OF FEMORAL OSTEOTOMY FIXED WITH INTRAMEDULLARY NiTi ROD

摘要

The purpose of this work was to evaluate the possible deleterious effects of NiTi on osteotomy healing, bone mineralization, and remodeling response. Femoral osteotomies of rats were fixed with either NiTi or Stainless Steel (SS) intramedullary nails. The longest follow-up period was 60 weeks. Bone healing was examined with radiographs, peripheral Quantitative Computed Tomography (pQCT), and histologically. There were more healed bone unions in the NiTi than the SS group at early (4 and 8 weeks) time points. Callus size was equal between the groups. The total and cortical bone mineral densities did not differ between the NiTi and SS groups. Mineral density in both groups was lower in the osteotomy area than in the other areas along the nail. Density in the nail area was lower than in the proximal part of the operated femur or the contralateral femur. Bone contact to NiTi was close. A peri-implant lamellar bone sheet formed in the metaphyseal area after 8 weeks, indicating good tissue tolerance. NiTi appears to be an appropriate material for further intramedullary use because it has good biocompatibility in bone tissue.