Study On The Change Of Microstructure Characteristics And Mechanism Of Osteonecrosis Of The Femoral Head Specimens Of Emu

Objective To establish a model that can simulate the human femoral head necrosis early femoral head necrosis model emu. Study on the characteristics of bone microstructure in different zones of necrosis of the femoral head specimens in emu. To investigate the cause of osteonecrosis of the femoral head, to seek a safe and effective clinical presserving treatment scheme.Materials and Methods Adult emu as the research object.Using a method of injection ethanol to establish the animal model with the osteonecrosis of the femoral head. The specimens of femoral head Micro-CT scan and pathology detection. The samples were divided into bone distruction region, hyperostosis region and normal region according to radiographic results, then the bone microstructure, micromechanics and osteoblasts/osteoclasts activity were analyzed by Micro-CT, RT-PCR.Result 1.The ethanol injection to establish the animal model of emu osteonecrosis.Bone metrology results showed that campared with the normal side femal head, the surgery side Tb.th increased 87%;the Tb.sp decresed 43%;the BMDand the Tb.N had no significant change. 2. The samples were divided into bone distruction region, hyperostosis region and normal region according to radiographic results.Bone distruction region of trabecular BMD,Tb.Th, Tb.N, were significantly lower than normal region. Tb.Sp increased compared with the normal region. The difference was statistically significant(P <0.05). Hyperostosis region of trabecular BMD, Tb.Th, Tb.N were significantly higher than health region. Tb.Sp reduced compared with the normal region. The difference was statistically significant(P <0.05).3.The pathological results showed that each region of trabecular bone micro structure has obvious difference. Destruction of trabecular bone in the bone distruction region, the density of trabecular bone in hyperostosis region became larger.4. The RT-PCR result showed that the RANK and RANKL staining level increased significantly in subchondral bone and bone distruction region compared with normal region, while OPG and BMP2 staining level increased significantly in hyperostosis region.Conclusion 1.Our induction protocol of ethanol injection resulted in consistent osteonecrosis of the femoral head that may serve a model to testing potential protocols for treatment of osteonecrosis. 2.The different region of the femal head showed significant differences induced by local injection of purified ethanol. 3.Modulation osteoblast/osteoclast activities could help preserve the femoral head, even reverse the process, then cure the osteonecrosis.