The effect of Theranekron on femur fracture healing in an experimental rat model

Objectives: The aim of this study was to investigate the radiological, biomechanical, histopathological and immunohistochemical effects of Theranekron on fracture healing in an experimental rat model. Materials and methods: Forty-eight male albino Wistar rats were used. Four groups were formed, with 12 rats in each of Theranekron groups 1 and 2, and control groups 1 and 2. After a fracture was created in the right femur of the rats included in the study, fixation was performed with an intramedullary Kirschner wire. Theranekron was administered subcutaneously to Theranekron groups 1 and 2 at a dose of 0.3 mg/kg on days 0, 5 and 10. After radiographic analysis of the femurs of Theranekron group 1 and control group 1 rats at four weeks of the study was performed, both groups were divided into two equal subgroups (six femurs in each group). Histopathological and immunohistochemical examinations were performed in one subgroup and biomechanical examination in the other subgroup. At the end of six weeks, the rats in Theranekron group 2 and control group 2 were evaluated after applying the same procedure as in the fourth week. Results: When the mean radiological scores of the Theranekron and control groups were compared, a statistically significant difference was found in favor of the Theranekron group at four and six weeks (p=0.028 and p=0.006, respectively). At four weeks, statistically significant higher biomechanical forces were obtained in the Theranekron group compared to the control group (p=0.030). In the histopathological evaluation, the inflammation value of the control group at four weeks was statistically significantly higher than the Theranekron group (p=0.027). The angiogenesis, osteoblast proliferation, and bone formation values of the Theranekron group were significantly higher than the control group (p=0.014, p=0.014, and p=0.005, respectively). At six weeks, the bone formation values of the Theranekron group were statistically significantly higher than the control group (p=0.021). The difference between the Theranekron group and the control group scores of the immunohistochemical evaluation were statistically significantly different at four and six weeks (p=0.006 and p=0.011, respectively). Conclusion: Theranekron may play a role in accelerating fracture healing by reducing acute inflammation process in the early period of fracture union, increasing fracture strength, angiogenesis, osteoblast proliferation, and bone formation.