An Experimental Research Of Repairing The Rabbit’s Lacunar Bone Defect In Lower Limb With Platelet-rich Plasma

Objective:Bone defect repair has been the important topic in the field of orthopedicresearch.The use of growth factors to promote and enhance bone of creepingsubstitution and new bone formation has gradually become the hotspot of current withthe deepening of the bone tissue engineering research.A large number of domestic andforeign literature reported that platelet-rich plasma (PRP) can promote bone tissuerepair and has clear bone induction ability[1].But there are also some scholars believethat platelet-rich plasma in animal experiment and clinical application can notpromote the bone regeneration and bone defect repair is not obvious with PRP’seffect.The main reason is that the researchers’ preparing standard of platelet-richplasma is not unified.Due to the study of individual differences in the preparation ofplatelet-rich plasma quality not unified, which may affect the results[2,3].Thisexperiment using platelet-rich plasma composite type injectable calcium sulphateartificial bone as bioactive new bone graft material, to repair rabbit lacunar bonedefect of lower limbs.Through the testing indexes to evaluate its ability to repair bonedefect,and preliminaryly discuss the allogeneic blood platelet rich plasma promotingbone defect repair mechanism, which is the preparation for the standardization of subsequent platelet rich plasma to provide the corresponding theoretical basis.Methods:1. PRP and artificial bone were mixed into PRP gel by2:1ratio after thepreparation of platelet rich plasma.2. Then40healthy New Zealand white rabbits were selected for theexperiment.The animals were randomly divided into2groups after bone defectmodels were made at the side of the animal tibia.The experimentalgroup:Intraoperatively filling in bone defect with the PRP gel;The controlgroup:Intraoperatively filling only artificial bone in bone defect.3. Animals were killed in3,5,7,9weeks postoperatively.Rabbit’s bone defectrepairing was observed through general, X-ray plain film, pathological biopsy andimmunohistochemical.Reference to Lane’s radiological criteria,each group of animalsis scored and record of bone repair of the bone defect shot density value.The area ofthe calculation of its positive ratio was showed up with the Image-Pro Plus.Finally thedata was analysised by using statistical software.Results:1. All animals’ incisions were healed well postoperatively.2. X-ray plain film results show that the experimental group compared withcontrol group the difference was statistically significant after3,5,7weeks（P <0.05）.3. Gross observation and HE staining showed defects of bone healing ofexperimental group is better than that in control group.4. Immunohistochemical observation showed that experimental immune stainingpositive area ratio is higher than the control group3,5weeks postoperatively.Conclusion:1. The healing and repairing of bone defect can be promoted with platelet-richplasma.2. VEGF is an important factor of stimulating bone tissue regeneration in theearly.