Experimental Study Of Establishing Chicken Models Of ONFH By Ligating Selective Vessels

Background and ObjectiveWith the development of the medical detection means,the morbidity of ONFH(Osteonecrosis of the Femoral Head) rises year by year.The therapeutic method of ONFH is still one of the most tough problems in orthopedic field,because so far we have not discovered a method which can stop or reverse the pathology course of ONFH and stop the further collapse of femoral head.All kinds of the new therapies for ONFH are based on the animal models which can imitate the natural pathological process of ONFH in human.In 1957, Pietrogrand reported that the glucocorticoid could lead to avascular necrosis of the femoral head easily,then,we have searched a perfect animal models to imitate the pathological process of ONFH in human all the time more than a half century.The animal models of ONFH include traumatic models and nontraumatic models.Various models have been established by these two methods,but no one can simulate the pathological process of ONFH in human completely from early necrosis to collapse in articularsurface.This experiment used the method of ligating selective vessels to establish the chicken model of ONFH,which is a new animal model for research of the medical treatment.Methods30 Tender Chicken(supplied by the experimental animal center of Zhengzhou University),regardless of male or female,weight 1.5-2.1kg,1.8kg averagely.Divided into two groups randomly, cutted open one side of femoral head in group-A(25 chickens),ligatured the artery around femoral and cutted off the round ligament of femur.5 chickens were cut open only.After 2w,4w,8w,12w,putted then to death in batches,taked out the femoral heads and observe d the appearance.Then cutted them into slices,dyed, observed the pathological change.ResultsTwo weeks later after operation,the femoral heads showed a little pallor,found marrow oedema.After 4 weeks, articularsurface looked rough, the empty lacunae increased, trabecula irregular.8 weeks later, articularsurface looked pallor,roughly, pallidly,more empty lacunae appeared,the empty lacunae rate was 75-90%.After 12 weeks,the femoral heads changed a little small,dead trabeculae became thin and irregular,some of them disintegrated into chips.The fracture below cartilage made more serious.ConclusionThe method of ligating selective vessels can establish the animal models of ONFH,which is a new-style model for the medical research.