Experimental Study On Promoting Bone Consolidation By Platelet-rich Plasma In Different Period During Distraction Osteogenesis

Objective To establish the rabbit model of tibial lengthening using the monolateral external fixation. Injecting platelet-rich plasma (PRP) at different period on distraction osteogenesis, To observe the effect on the distraction osteogenesis. To discuss the effect on the mineralization process of distraction osteogenesis at different period, and provide the theoretical basis on promoting bone consolidation and healing.Methods Forty Japanese rabbits (weighing2.5-2.8kg) were randomly divided into4groups (n=5). The experimental group was performed the tibial osteotomy fixed the monolateral external fixator and began distraction at five days after surgery in a rate of lmm/d for twice a day. In group A,5days after operation, inject PRP500ul1times in the beginning of lengthening; In group B,15days after operation, inject PRP500ul1times in the beginning of; In group C,25days after operation, inject PRP500ul1times at the middle of mineralization period; In the group D (control group), lengthening without injection of PRP. The X-ray films were taken at0,15,25,35days after operation, At37days after operation, the tibial specimens were harvested and HEcoloration and scanning electron microscope(SEM) was used to observe bone regeneration.Results1. X-ray:The X-ray films showed that new bone formation in groups B and C was obviously better than that in groups A and D at35days after operation.2. Measure the trabecular bone area ratio (Tb.AR) in HE staining:select10randomly in100times magnification view, trabecular bone area ratio (Tb.AR) of group B and group C were significantly higher than those of groups A and D (P<0.05); Trabecular bone area ratio (Tb.AR) of group C were significantly higher than those of groups B (P<0.05); There was no significantly difference in Tb.RA between groups A and B (P>0.05).3. The observation of scanning electron microscope (SEM):the cell ultrastructure of groups B and C of were significant different from groups A and D.Conclusion It is well that the rabbit model of tibial lengthening using the monolateral external fixation can imitate the clinical lengthening process in this study. local injection of PRP can promote bone consolidation during distraction osteogenesis effectively, especially in the middle period of distraction osteogenesis.