中文摘要：

目的应用Micro CT对正常C_5椎弓根部位进行扫描,分析椎弓根结构的骨小梁显微结构特点并测量相关指标。方法选取5例C5颈椎骨结构完整的成人干燥骨标本,年龄45～57岁,使用Micro CT对其C5椎弓根标本进行扫描。以Inveon Research Workplace软件对横断面重建图像分别选定3个兴趣区（50×50×50）,计算各兴趣区内骨小梁体积/样本体积（BV/TV）、骨面积体积比（BS/BV）、骨组织表面积（BS）、骨小梁厚度（Tb.Th）等参数,分析骨小梁结构特点、寻找滋养孔并测量统计选定区域骨皮质厚度和髓腔径线。结果 Micro CT扫描数据经过三维重建后能够清晰显示椎弓根结构骨小梁的显微结构,板层状骨小梁通过斜形棒状骨小梁组成立体网状结构。椎弓根骨髓腔各部分兴趣区BV/TV、BS/BV、Tb.Th、TN值差异均无统计学意义（P〉0.05）;椎弓根中部皮质厚度及髓腔径线与椎弓根前部和后部皮质厚度及髓腔径线差异有统计学意义（P〈0.05）,并发现滋养孔结构。结论应用Micro CT可以获得正常颈椎椎弓根结构的精细显微图像,可用于分析椎弓根结构的各项指标,也可以进一步应用于有限元分析。

英文摘要：

Objective To measure and analyze the microstructures of the 5th cervical vertebra with micro CT.Methods Micro CT scans were obtained from the 5th cervical vertebra of bone specimens of 5 adult cadaver who aged 45 to 57 years old.The scanned data were reconstructed with the Inveon Research Workplace.After being reconstructed with the Inveon Research Workplace,3 regions of interest（50×50×50,pixe3） were chosen in a coronalplane so that the results of bone volume/total volume（BV/TV,%）,bone surface area/bone volume ratio（BS/BV,mm^-1）,bone surface（BS,mm）,trabecular thickness（Tb.Th,mm）,and trabecular number（TN,mm-1） were measured.The characteristics of the bone trabecular structure and the nutrient foramina were analyzed,and the thickness of bone cortex and medullary cavity diameter were measured.Results Trabecular microstructures were obtained after 3D reconstruction of micro CT scans of the 5th cervical vertebra.The lamellar-like trabecular bone make up a complex net-like micro-construction combined with rod-shaped trabecular bones in all direction.There was no significant difference in BT/TV,BS/BV,Tb.Th,TN compared with the regions of interest of the 5th cervical vertebra（P〈0.05）.The thickness of bone cortex and medullary cavity diameter between different parts of the 5th cervical vertebra were of statistically significant difference（P〈0.05）.And the nutrient foramina were discovered.Conclusion High-resolution 3D images of the 5th cervical vertebra can be obtained with micro CT as so to analyze not only the bone micro-structures but also the finite element and so on.