绝经后女性腰椎应力分布及骨折风险的FEA研究  

Finite element models predict vertebral strength of postmenopausal women

作　　者：王立英[1] 蔡跃增[1] 吴胜勇[2] 兰静[1] 王鹏林[3] 李景学[1] 

机构地区：[1]天津医科大学总医院放射科,天津300052 [2]天津市第一中心医院 [3]天津理工大学CAE中心

出　　处：《中国骨质疏松杂志》2009年第8期557-562,共6页Chinese Journal of Osteoporosis

摘　　要：目的用有限元法分析骨质疏松及椎间盘退变对腰椎应力分布及骨折风险的影响。方法应用GE Light Speed16型MSCT容积扫描数据创建正常人腰2～4节段的三维有限元模型;选取正常、骨质疏松及骨质疏松伴骨折患者各10例,模拟生理载荷下腰椎应力分布,分析骨质疏松及椎间盘退变对腰椎应力分布的影响;计算椎体内应变≥5000μ strain的骨小梁体积占骨小梁总体积的比例,作为骨折小梁比例F%。结果在正常椎间盘状态下,腰3椎体内应力分布呈三维＂工＂字形结构。骨质疏松后,骨折小梁比例增加,易骨折部位位于小梁中心区域。椎间盘退变后,高应变区向椎体周围转移,以椎体前缘皮质下方为著,骨质疏松伴骨折组骨折小梁比例明显减少（约83.6%）。结论骨质疏松对腰椎应力分布没有影响,骨折小梁比例增加,易骨折部位位于椎体中部。椎间盘退变可以减少邻近椎体骨折风险。Objective A finite element study to investigate the influence of osteoporosis and disc degeneration on the load transfer of the lumbar spine. Methods MSCT data of vertebral bodies were used to construct finite- element analyses of L2.4 to determine the physiologic load transfer in the vertebrae. Analyze the influence of osteoporosis and disc degeneration on the load distribution of vertebrae. Calculate the amount of trabecular bone at risk of fracture（F% ）, which are those with strains exceeding 5000 ~tstrain. Results Under normal intervertebral disc status, the stress distribution in L3 was like a three dimensional ＂工＂. With decreasing BMD, the trabeculae at risk of fracture increased, which is located in the center of the trabecular core. For degenerated discs, load was transferred from the trabecular core to the peripheral region especially in the anterior cortical shell, the stress in the trabecular core decreased, then the percentage of trabeculae at risk of fracture decreased （83.6% in fractured group）. Conclusion Osteoporosis had no effect on the load distribution of vertebra, but had a significant effect on the amount of trabecular bone at risk of fracture which is located at the center of the core. For a degenerated disc, trabecular core carried fewer loads, which decreased the amount of trabecular at risk of fracture.

关 键 词：骨质疏松 骨密度 骨强度 有限元法 骨折风险 

分 类 号：R589[医药卫生—内分泌]