人体下腰椎显微骨硬度分布特征研究

The hardness variations and characteristics of human lower lumbar vertebra by Vickers microindentation

目的:探讨人体下腰椎显微骨硬度的分布特征。方法:选取三具新鲜尸体捐献者,取出L3~L5椎体后剔除软组织。按脊柱两柱理论将椎体分为椎体区和附件区,并使用高精慢速锯,于椎体区垂直上下终板切割4片,右侧附件区沿椎弓根长轴切割1片,左侧附件区沿上下关节突长轴切割(1片),将骨骼制备成若干厚约3mm的骨组织切片,并经砂纸打磨。9块椎骨共计产生54分骨组织切片(椎体区36片,附件区18片)。应用维氏方法测量骨切片不同区域骨皮质和骨松质的显微硬度值(单位:HV)。采用50g力加载50s、维持12s的标准操作方法测定,每一个区域选取5个有效硬度值,取平均值作为该区域的硬度值。每块椎体选取11个区域,9块椎体共进行495次有效压痕实验并取得显微硬度值,观测不同部位显微骨硬度分布特征。结果:下腰椎硬度范围为20.7~48.8HV,其中皮质骨骨硬度为32.86±5.35HV,松质骨骨硬度为31.25±3.55HV;其中皮质骨平均硬度为32.11±5.17HV,附件区皮质骨平均硬度为33.46±5.43HV;椎体区松质骨平均硬度为30.41±3.07HV,附件区松质骨平均硬度为32.10±3.83HV,附件区皮质骨骨硬度/松质骨骨硬度均高于椎体区,差异具有统计学意义(P<0.05);L3~L5不同受试者下腰椎同一部位的骨硬度数值不同,但是部位之间的变化规律与整体一致。结论:下腰椎不同部位的显微骨硬度值存在显著差异,附件区皮质骨和松质骨骨硬度分别高于椎体区皮质骨和松质骨骨硬度。

Objectives: To explore the variations and characteristics of micro-hardness of human lower lumbar vertebra. Methods: L3-L5 vertebrae were harvested from three fresh cadaver donors. The soft tissues were removed. According to the two-column theory of spine, each vertebra was divided into the vertebral body area and the attachment area. 4 specimens perpendicular to the upper and lower endplates were cut in the vertebral body area, meanwhile, 1 specimen parallel to the long axis of the vertebral pedicle and 1 specimen perpendicular to the superior and inferior articular process was cut in the attachment area by using a high-precision slow-speed saw. All specimens were sanded(Unit: HV). A total of 54 bone specimens was produced from 9 vertebrae(36 specimens in the vertebral body area and 18 specimens in the attachment area). The Vickers method was used to measure the micro-hardness of cortical bone and cancellous bone in different areas. The standard operation method of loading 50g for 50s and maintaining for 12s was choosen. Five effective hardness values were selected for each region, and the average value was taken as the hardness of the region. 11 regions were selected for each vertebra, and 495 effective indentations were performed. Results: The hardness range of the lower lumbar vertebra was 20.7-48.8 HV, with the average hardness of the cortical bone as 32.86±5.35 HV and the average hardness of the cancellous bone as 31.25±3.55 HV;the average hardness of the cortical bone in the vertebral body area as 32.11±5.17 HV, the average hardness of cortical bone in the attachment area as 33.46±5.43 HV;the average hardness of cancellous bone in the vertebral body area as 30.41±3.07 HV. The average hardness of cancellous bone in the attachment area as 32.10±3.83 HV. The hardness of cortical bone/cancellous bone in the attachment area was higher than that in the vertebral body area, and the difference was statistically significant(P<0.05). L3-L5 different subjects had different bone hardness in the same region of the lumbar vertebra, but the changes among the regions were consistent with the whole. Conclusions: There are significant differences in the hardness from different regions of the lumbar vertebra. The hardness of the cortical bone and cancellous bone in the attachment area is higher than that of the cortical bone and cancellous bone in the vertebral body area.