Safety and Effectiveness of Using Double-Ended Allograft in the Repair of Large Defects of Bi-Epiphyseal Bones in Experiment

BACKGROUND: The repair of large defects in the long bones remains one of the most pressing problems in traumatology and orthopedics. AIM: To evaluate the effectiveness and technological safety of the repair of large defects of the long bi-epiphyseal bones including the use of double-ended bone allografts to demarcate the defect cavity from the surrounding tissues and fixation of bone fragments using an external fixation device. MATERIALS AND METHODS: Experiments were conducted on 14 adult nonpedigree male and female dogs aged 1–2 years. The double-ended allograft was used to demarcate the formed defect of the tibial bones at 1.5 diameter length of the shinbone. The bone fragments were fixed with Ilizarov apparatus adapted for experiments on dogs. The maximal follow-up period was 2 years after the surgery. In the dynamics of the experiment, life-time observations, X-ray examination, and laboratory control were conducted. After euthanasia, the implantation zone was examined histologically. RESULTS: The visual signs of the restructure of the transplants were identified starting from day 35 after surgery. The bone regenerates in the defect zone completely formed within 3 months after the surgery. This permitted the removal of the external fixation apparatus in 3 months after the surgery. The restructuring of the newly formed part of the bone continued for 2 years after the operation. No significant changes in the laboratory parameters in the dynamics of the experiment were observed. No changes could be evaluated as negative phenomena. No serious unwanted events were recorded either. CONCLUSION: The proposed technique for the repair of large defects of long bi-epiphyseal bones demonstrated safety and sufficient effectiveness in the speed of regeneration of the defect and quality of the bones formed.