The effect of thranekron and autograft bone on bone defect healing in rabbit model

Nowadays, bone grafting is used in both human and veterinary orthopedics to stimulate fracture healing, accelerate arthrodesis, and to restore bone defects. In such procedures, orthopedic surgeons are searching to favorable substitute for autograft bone. The present study seeks to investigate the use of Theranekron in bone defect healing process. 20 native rabbits (male rabbits weighing approximately 2 kg and aged 1.5-2 years) were divided into 4 groups of five, and bone fragments were removed from their radius bones. In the first group, Theranekron 1mg/kg was injected into bone defect. Normal saline was injected into the same site of the five rabbits in the second group (saline treated controls). As for the third group (the untreated controls), nothing was injected. In the fourth group (autograft group), the removed bone was put in place and muscle and skin were sutured. Post op lateral x-rays were prepared on days 14, 28, 42, and 56. Bone biopsy for histopathological study was performed after 8 weeks. Radiographs and samples were analyzed statistically in terms of union, osteogenesis activity, and bone Remodeling. Results: Radiological evaluation showed that autograft group was significantly superior to both untreated and saline treated controls (p=0.02, p=0.04, respectively). Also, Theranekron group proved better than untreated controls (p=0.04). Histopathological evaluation showed terabecular bone and bone marrow formations in Theranekron and also autograft groups. In the untreated and saline treated controls, most part of defect was filled with fibrous tissue. Conclusion: Theranekron treated group showed almost similarly to autograft counterpart, but better than normal saline and untreated controls. Keywords: Thranekron, Bone repair, Autograft, Rabbits