Experimental Study On Therapy Of Avascular Necrosis Of The Femoral Head With Vascular Endothelial Growth Factor

Objective 1.To establish animal model of avascular necrosis of the femoral head in rabbits induced by glucocorticoid.2.To explore a new method for thetherapy of avascular necrosis of the femoral head with percutaneous injection of VEGF₁₂₁.Method Thirty-two adult New Zealand white rabbits were divided randomly into three groups:A,control group(n=10);B model group(n=10);C treatment group(n=10)。Model group and treatment group were injected with 10ml/kg equine horse serum into ear-vein.After two weeks,they were injected with 5ml/kg equine horse serum into ear-vein for 2 days.And then they were injected intraperitoneal with 7.5mg/kg of dexamethasone sodium phosphate for 3 times(three days every time).After that,treatment group was injected of VEGF₁₂₁with percutaneous with 600ug/kg,the control group was injected of physiologic saline.After the experiment at 6 weeks,We observed the necrosis of samples through X-ray and pathological section and The immunohistochemistry study for rabbit VEGF.Result 1)All the femoral heads we takened out were intact.The surface of femoral heads was white,slice and firm in group A;while it was superficially blue and thin in group B;slightly white and intermedial hard between groupA and B in group C.trabeculae(P＜0.05).2)The empty Cartilage cell lacunae ratios of groupB and C were showed significantly increased than group A, and Group C shows significantly degraded than group B(P＜0.05).3)The numbers of blood vessel under cartilage in group B was significantly reduced than group A,while group C was significantly increased to compare with group A(P＜0.01).4)The result of osteoblast amounts was the same statisticsresults with the numbers of blood vessel;The osteoclast amounts in groupB and C all were significantly increased than group A,and group C was increased significantly than group B(P＜0.05).5)The immunohistochemistry study for rabbit Collagen Typeâ… shows group B made a light color than group A,while groupC was made a deep color than group A.Conclusion 1.Avascular necrosis of the femoral head model was successfully established in rabbits.2.It is indicated that percutaneous injection of VEGF could significantly enhance bone tissue angiogenesis.Repair of osteonecrosis could be ameliorated accordingly,thus providing a potential method in the treatment of the femoral head necrosis.