复合PRP与BMP-4的Nano—HA并髓心减压治疗兔股骨头坏死

目的探讨富含血小板血浆（PRP）与骨形态发生蛋白-4（BMP-4）的纳米羟基磷灰石（NanoHA）联合髓心减压修复兔股骨头坏死的可行性。方法激素法制备新西兰大白兔股骨头坏死模型，取36只随机分为A、B、c共3组，各12只。A组为模型组，不进行任何处理；B组行单纯髓心减压术；C组髓心减压后植入富含PRP与BMP-4的Nano—HA。分别于术后2、4、8周处死大白兔，取股骨头进行组织学观察及骨小梁图像分析，并在第8周测定股骨头骨密度。结果组织学观察显示，从术后第2周开始C组的成骨能力一直好于A、B组，C组术后2周时开始出现骨小梁，术后8周时骨小梁已成熟，骨髓组织形成；B组术后8周时缺损区仍然在修复，可见骨髓组织；A组术后8周时仍无骨组织。骨小梁图像分析显示，C组术后2、4、8周骨小梁所占缺损区面积比例均高于B组，差异有显著性（t=2．459～2．949，P〈0．05）。骨密度测定显示，术后8周c组的骨密度高于B组及A组，差异有显著性（F=13．655，P〈0．05）。结论PRP协同BMP-4可诱导坏死的股骨头内新生骨的形成，PRP协同BMP-4搭载Nano—HA联合髓心减压能加速兔股骨头坏死修复。

EFFECT OF NANO-HYDROXYAPATITE COMBINED WITH PRP AND BMP-4 CORE DECOMPRESSION ON TREATING NECRO- SIS OF THE FEMORAL HEAD IN RABBITS

Objective To discuss the feasibility of Nano-Hydroxyapatite （Nano-HA） combined with platelet rich plasma （PRP） and bone morphogenetic protein 4 （BMP 4） core decompression in the treatment of necrosis of femoral head in rabbits. Methods Animal models of femoral head necrosis were created in rabbits by injecting hormone,36 of them were enrolled and even- ly randomized to three groups as A, B and C. Group A was a model group, no any treatments were given; group B, treated with core decompression only~ group C, Nano-HA combined with PRP and BMP-4 was implanted after core decompression. The rabbits were sacrificed respectively two, four and eight weeks after surgery, the femur heads were taken for histology and bone trabeculae analysis. The bone density was measured on the 8th week. Results Histology showed that the osteogenic potential in group C was constantly better than groups A and B starting from the second week after surgery with bone trabecula appeared, and on the 8th week, the bone trabecula matured, myeloid tissue formed. In group B, the defect areas were still repairing in this period. No bone tissue in group A was noted eight weeks after surgery. Bone trabecula image analysis indicated that the bone trabecula propor- tion in group C was higher than group Btwo, four and eight weeks postoperatively, the difference was statistically significant （t = 2.459--2.949 ,P〈0.05）. Bone densitometry demonstrated-eight weeks after surgery-bone density in group C was higher than both groups B and A, the difference being significant （F= 13.655,P〈0.05）. Conclusion PRP combined with BMP-4 can induce new bone formation inside the necrotic femur bone, and Nano-HA combined with PRP and BMP-4 after core decompression can accele- rate repairing femoral head necrosis in rabbits.