腰椎小关节骨赘成骨潜能的形态学研究

Morphological study on osteogenic potential of the lumbar facet joint osteophytes

目的 分析腰椎小关节骨赘的形态学特征,探讨其成骨潜能及作为植骨材料的可行性.方法 选取2013年1月至2014年9月腰椎融合手术时所取腰椎小关节骨赘25例作为骨赘组,男14例,女11例;年龄43～60岁,平均（48.8±5.46）岁;另取髂骨松质骨11例作为髂骨组,男7例,女4例;年龄40～59岁,平均（47.8±6.13）岁.采用HE染色观察比较骨赘与髂骨的结构和成骨细胞数量及分布;通过Real-time PCR和免疫组织化学染色检测骨形态发生蛋白2（bone morphogenetic protein 2,BMP-2）、转化生长因子β1 （transforming growth factor beta1,TGF-β1）、胰岛素样生长因子1（insulin-like growth factor-1,IGF-1）、碱性成纤维细胞生长因子（basic fibroblast growth factor,bFGF）和血管内皮生长因子（vascular endothelial growth factor,VEGF）等骨诱导生长因子在髂骨和骨赘中的表达和分布;利用Micro-CT观察髂骨和骨赘内部的三维结构.结果 通过HE染色发现,骨赘中可见完整的骨小梁,成骨细胞沿骨小梁表面排列,但较髂骨分布稀疏,数量较少.Real-time PCR和免疫组织化学染色显示BMP-2、TGF-β1、IGF-1、bFGF和VEGF等五种生长因子在骨赘中均有表达,结果显示BMP-2、bFGF和VEGF在髂骨和骨赘中的表达差异无统计学意义,而TGF-β1和IGF-l的表达较髂骨弱;免疫组织化学染色发现,BMP-2和bFGF在两组中的表达差异无统计学意义,而TGF-β1、IGF-1和VEGF在骨赘中的表达弱于髂骨.Micro-CT检测发现,骨赘具有与髂骨相似的孔隙内交联结构,其孔隙率为63.00％±6.08％,骨小梁数、骨小梁厚度和骨小梁间隙等参数骨赘和髂骨差异无统计学意义.结论 腰椎小关节骨赘具有与髂骨相似形态学特征,具有一定的诱导成骨的能力,可作为自体骨或人工骨等植骨材料的补充.

Objective To analyze morphological features and osteogenic potential of lumbar facet joint osteophytes,and to investigate the feasibility as a grafting material.Methods Lumbar facet joint osteophytes were harvested from 25 cases which aged from 43 to 60 years during the lumbar fusion surgeries from January 2013 to September 2014,including 14 males and 11 females;with an average age of （48.8 ±5.46） years.Iliac cancellous bone was harvested from 11 cases which aged from 40 to 59 years as the control,including 7 males,4 females,with an average age of （47.8 ± 6.13） years.Internal trabecular structure,the distribution and number of osteoblasts in the osteophytes and cancellous iliac were detected by HE staining.The expression levels and distribution of BMP-2,TGF-β1,IGF-1,bFGF and VEGF in two groups were investigated by real-time PCR and immunohistochemistry.Three-dimensional structures of internal osteophytes and iliac cancellous bone were measured by micro-CT.Results HE staining showed there were integrated trabecular structures in osteophytes,and osteoblasts attached along the surface of trabecular,which were less than that in iliac cancellous bone.Real-time PCR and immunohistochemistry showed the expression of BMP-2,TGF-β1,IGF-1,bFGF and VEGF in osteophytes.The expression of BMP-2,bFGF and VEGF had no significant difference between the two groups in real-time PCR,and the expression of TGF-β1 and IGF-1 were weaker in osteophytes.Immunohistochemistry showed no significance difference on the protein levels of BMP-2 and bFGF between two groups,and the protein levels of TGF-β1,IGF-1 and VEGF were lower in osteophytes.Micro-CT scanning showed porous cross-linked structure in osteophytes,and porosity was 63.00%±6.08%.There was no significant difference between osteophytes and iliac on parameters of trabecular number,trabecular thickness and trabecular separateion.Conclusion The lumbar facet joint osteophytes have similar morphological characteristics with iliac cancellous bone.With osteogenesis potential,lumbar facet joint osteophytes might be used as a supplementary for autologous bone or artificial bone.