带BMP椎弓根钉修复羊椎体骨缺损的研究

Repair of Sheep Vertebra Defect with Nover Pedical Screw with BMP

目的分析带有骨形态发生蛋白(bone morphogenetic protein,BMP)同种异体骨的新型椎弓根钉在修复羊椎体内骨缺损的作用特点。方法选取健康成年山羊12只,建立腰椎椎体内骨缺损的模型,所有动物被分为3组,每组均为4只。分别对各组动物进行腰椎椎体的生物力学检测(包括轴向最大拔出力、垂直压缩刚度及极限压缩强度),比较新型椎弓根钉组与普通椎弓根钉组动物腰椎椎体的不同生物力学检测结果的差异;采用HE染色法进行病理染色,分别在第4周和第12周时观察和比较各组动物腰椎椎体骨缺损区的组织形态学差异;采用RT-PCR法检测和比较在第4周和第12周时各组动物腰椎椎体骨缺损区BMP-2mRNA含量的差异。结果新型椎弓根钉组平均轴向最大拔出力、极限抗压强度明显高于普通型组,差异有显著性(P<0.05),即刻状态的整体刚度新型椎弓根钉组与普通型组比较,差异无显著性(P>0.05)。与普通型椎弓根钉组及空白对照组相比较,新型椎弓根钉组在植入后第1周和第4周BMP-2mRNA含量均增多,各组间比较差异有显著性(P<0.05)。结论 BMP-2有很强的促进成骨细胞分化和诱导体外成骨的能力,因此带BMP-2的新型椎弓根钉在骨缺损中的治疗有重要的临床意义,值得临床推广应用。

Objective To explore features of novel lumbar pedicle screw with BMP in the repair of bone defects in sheep vertebral body. Methods Twelve adult sheep were used to construct bone defects models. All animals were di vided into three groups. We compared the difference for the biomechanics of the maximum pullout strength,the stiff ness modulus of immediately state after reconstruction and the ultimate compressive strength and observed tissue characters of lumbar spine by HE pathological staining method and test BMP-2mRNA expression by RT-PCR at the fourth and twelfth week in different groups. Results The maximum pullout strength was higher in novel than com- mon （P^0.05）. There were difference about values of the ultimate compressive strength of immediately state after re construction. In novel group ,the histological observation found there was difference between control group and novel group. The BMP-2mRNA expression in the first and fourth week and in outer and central space is higher in novel group than in control and common group ,there is significant difference among them. Conclusion BMP-2 can strongly accelerate osteoclasts fissure and induce bone formation in outside bone,so the novel lumbar pediele screw with BMP is very important for treating bone defect,it worth applying for clinical therapy.