【作者】 张波；

【导师】 杨惠林；

【作者基本信息】 苏州大学 ， 脊柱外科， 2011， 硕士

【摘要】 【目的】通过制备可注射双相磷酸钙/丝素蛋白/硫酸钙/rhBMP-2 (biphasic calcium phosphate/silk fibroin/calcium sulphate hemihydrate/recombinant human bone morpho- genetic protein-2, BCP/SF/CSH/rhBMP-2)复合材料,并进行动物体内降解、生物相容性及椎间融合的实验研究。【方法】8只健康成年绵羊被随机分为两组,每组四只,均经左侧腹膜外入路,暴露L1/2、L3/4和L5/6椎间盘,在其中点制成深度为12mm,直径为7.0mm的垂直于矢状面的孔洞,不穿透对侧纤维环,完全清除髓核组织,充分处理终板至渗血。每只绵羊三个腰椎椎间隙孔洞随机植入下列材料中的三种:BCP/CSH/SF、BCP/CSH/rhBMP-2、BCP/CSH/SF/rhBMP-2或自体松质髂骨。分别于术后3、6个月处死两组绵羊,通过大体观察、手触检测、CT扫描、非破坏性生物力学测试、不脱钙组织学以及组织形态学方法观察和分析脊柱融合状况。【结果】除作为对照研究的自体髂骨不能经注射器注入外,其余人工骨注射过程均较流畅。术后腰椎标本完整性均良好,无附件等组织破坏,对侧纤维环均没有穿破,钻孔侧椎旁无渗漏。手触检查结果表明:术后3个月时,BCP/CSH/SF、BCP/CSH/rhBMP-2、BCP/CSH/SF/rhBMP-2以及自体松质髂骨植骨融合率之间无统计学意义(P>0.05);而术后6个月时,四组材料的融合率也无统计学意义(P>0.05)。非破坏性生物力学测试显示:术后3个月时,屈曲、后伸、左侧屈以及右侧屈四个施力方向的融合强度的差异有统计学意义(P<0.05);术后6个月时,BCP/CSH/SF/rhBMP-2与自体髂骨表现出相近的力学强度(P>0.05),两者在四个方向的融合强度>BCP/CSH/ rhBMP-2 >BCP/CSH/SF,差异有统计学意义(P<0.05)。组织形态计量学表明:术后3个月时,四组材料之间差异具有有统计学意义(P<0.05);而钙磷残留量的差异也有统计学意义(P<0.05);术后6个月时,BCP/CSH/SF/rhBMP-2成骨能力与自体髂骨相当(P>0.05),二者新骨生成量>BCP/CSH/rhBMP-2>BCP/CSH/SF,差异有统计学意义(P<0.05);而钙磷残留BCP/CSH/SF>BCP/CSH/rhBMP-2>BCP/CSH/SF/rh- BMP-2,差异也有统计学意义(P<0.05)。【结论】腰椎间隙孔洞深度为12mm,直径为7.0mm的绵羊腰椎体间融合模型是一种较为理想的动物模型,可以用来评估BCP/CSH/SF/rhBMP-2复合材料的成骨性能。BCP/CSH/SF/rhBMP-2复合人工骨具有良好的生物相容性与可生物降解性;构建的组织工程化人工骨具有良好的骨缺损修复作用及椎间融合效果,有望成为一种新型骨修复材料。更多还原

【Abstract】 [Objective] Through the preparation of injectable biphasic calcium phosphate/ calcium sulphate hemihydrate/silk fibroin/recombinant human bone morphogenetic protein-2(BCP/CSH/SF/rhBMP-2) composite materials, and do some experimental study of interbody fusion, the degradation and biocompatibility in vivo.[Methods] Eight sheep were randomly divided into two groups. Four sheep in each group were operated on left retroperitoneal approach and intervertebral discs of L1/2, L3/4 and L5/6 were exposed. Cavities were made on the midpoint of disc space perpendicular to sagittal plane, with 12 mm in depth and 7 mm in diameter. The opposite side of annular fibrosus was kept intact, nucleus pulposus was cleared completely, and endplate was processed to capillary hemorrhage. Three fusion sites in each animal were randomly assigned three treatments of four: biphasic calcium phosphate/calcium sulphate hemihydrate/silk fibroin(BCP/CSH/SF)、biphasic calcium phosphate/calcium sulphate hemihydrate/recombinant human bone morphogenetic protein-2(BCP/CSH/rhBMP-2)、biphasic calcium phosphate/calcium sulphate hemihydrate/silk fibroin/recombinant human bone morphogenetic protein-2 (BCP/CSH/SF/rhBMP-2) or autogenous iliac crest cancellous bone. sheep of the two groups were killed at 3 and 6 months postoperation respectively. The fusion sites were observed and analyzed by manual palpation, CT scan, undestructive biomechanical test, undecalcified histology, and histomorphology.[Results] All the bone subsitutes were injected successfully while the iliac cancellous bone couldn’t be injected by syringe. The structures of all the lumbar spine specimens were presvered integrity with favorable stability and without appendix destroyed. The opposite side of annular fibrosus was kept intact and no leakage of bone substitutes was observed in the drilling side. The fusion rates of BCP/CSH/SF、BCP/ CSH/rhBMP-2、BCP/CSH/SF/rhBMP-2 and autogenous iliac cancellous bone assessed by manual palpation at 3 months and at 6 months postoperation, the fusion rates had no significant differences (P>0.05) . Respectively, the fusion stiffness of all directions among the three materials had significant differences (P<0.05) at 3 months postoperation. Statistical differences were not detected between BCP/CSH/SF and intact specimen (P>0.05). It revealed similar stiffness between iliac bone and BCP/CSH/SF/rhBMP-2 at 6 months after surgery (P>0.05). The similar stiffness of the two materials were greater than BCP/CSH/SF (P<0.05). The new bone formation among the three materials had significant differences (P<0.05) at 3 months postoperation. The residual volume of calcium phosphate has significant differences (P<0.05) among the two bone substitutes. It revealed almost new bone formation between iliac bone and BCP/CSH/SF/rhBMP-2 at 6 months after surgery (P>0.05). The similar bone formation volume of the two materials were more than BCP/CSH/SF (P<0.05). It showed the same tendency about residual volume of calcium phosphate with at 3 months postoperation.[Conclusion] The sheep anterior lumbar intervertebral fusion model, of which the cavities are made on sheep intervertebral space with 12 mm in depth and 7 mm in diameter, is an ideal fusion model to evaluate the capability of bone formation for injectable bone subsidies. The BCP/CSH/SF/rhBMP-2 composite artificial bone has good biocompatibility and biodegradability; construction of engineering artificial bone has a good repair of bone defects and interbody fusion and will be expected to become a new bone repair materials.更多还原