Animal Model For Focal Osteonecrosis Of Femoral Head And Its Application

Animal model is an important tool for experimental research,kowever,date to now,there is no ideal animal model for osteonecrosis of femoralkead. Osteonecrosis of femoral head define to a series pathological processfollowing tbe death of living cell(including osteocyte,marrow cell andadipocyte).The essence of osteonecresis of femoral bead is the etisting uecrosisof bone trabecula and morrow tissue.The is the gold stadard to diagnoseosteonecrosis of femoral head.Literature confirms zinc chloride is a compound that has special effect, zincchloride has 3 aspects characteristic in bone tissue:(1)Cytototicity Zincchloride is salt of heavy matals,and can integrate to protein of cell to formaibumen salt and hydrochloric acid.and results in the death of cell.(2)Powerfulpermeability. The effects of the salt of heavy matals to protein ralated to tbedense its albumen salt. The dense of albumen salt for salt of zinc is very low.Itmakes medine easy to permeate. Hhe reserch has shown tbe osmosis of zincchloride is more powerful than formalin.(3)No influence to the bone healingand repair.Based on knowledge of above,we think to place zinc chloride in thefemoral head.In mean time,seals the extermal os using biological adhesivematerial.By this way,A close tune is develeped in the femoral head. Because ofexuduation of blood and tissue fluid, The zinc chloride would dissolve in thetune to form solution of zinc chloride.The powerful permeability andcytotoxicity of solution of zinc chloride in the bone tissue makes it can kill theosteocyte and marrow celI at its reach, Thus an osteonecrosis foci is develepedin this area.Then repairing reaction is evocationed .A serial pathphysiologyProcess for osteonecrosis of femoral head happens.The animal model forcerterin area osteonecrosis is develeped.As tbe tkeorical bases of develeping animal model for osteonecrosis usingzinc ckloridenye stttdy tke tOric effect of zinc cbloride to osteoblast in vitre intke first part of tkis tkesis. Tke results sbow zinc ckloride can alll 50o/oosteoblast in cultivatation as low a8 0.01gh.The effect has posfore correlationto tbe density of zinc ckloride(P<0.05).Based on reult8 of part one,as ourplan,we place zinc cbloride in the femoral head by operation in tke part two ofour tkesis.Periodic pathological and imagologicaI observatiou indicate thefollowing result:Zinc cbloride can ha osteoCyte and marme cell in affectingarea as earty as 2 days after opendion to lead to tke focal osteonecrosis in thefemoral kead.6 weeks after operation,large moumt of new bone formate inbyperPlastic fibreus tissue surrounding tke necrosis bone.Tke Xrny plain filmsbows obvious focal osteonecrosis.We rwiew deta~ tbe etoting animal modelin the tkesi8.As controlnye di8cuss tke cbaracteristic of tkis new model:(1)Theprocess to develop is simple.(2)Tke wound is small,and the animaI survival rateis kigh,and can move earlier.(3)Righ success rate to model develePing.(4)Tbesise and location can be controled tkeorically.To know tke model deeply,andevaluate tke model sciencifically,we anaIyze the dmerence bdeeen this modeland patient suferring from ostbonecrosis of femoral head.Altbougk tbe wide use of necrosis foci removing and bone grafting intreatment of osteonecresis of the femoral bead,1t is sun unknown tbat whatkerand kow tke grafing bone can finish boue keding and in tke femoral beadwbicb kas speciaI pbysiological' blood circulation and biomechanicsckaracteristic compared witk otker Part.How to improve tke speed and qualityof bone kealing by some way to reduce the patients anguish to least degree.Tkisproblem is studied in tke part 3 of the tkesis.ReCombinating kuman bone morPbogenesis protein(rkBare2) is a kind ofnew hone spliting and pek factor adoPting recombination tecknique of geneengneering.Animal and clinical e1periment has Proved it can induceundifferentiated mesenchymal cell around Planting area fOrm cartilage andne...