椎体成形术中不同骨水泥容量及位置的生物力学评估  

Biomechanical evaluation of different bone cement volumes and locations in vertebroplasty

作　　者：简志训 陈政行 林建宇 陈文斌 

机构地区：[1]中原大学医学工程研究所,杨梅天成医院骨科 [2]中原大学医学工程研究所

出　　处：《中华创伤骨科杂志》2005年第10期903-907,共5页Chinese Journal of Orthopaedic Trauma

摘　　要：目的利用有限元实体模型来评价植入不同骨水泥的量与部位,以及椎体成形术后椎体的应力分布。方法本研究分为两部分,首先是采用患者的计算机断层影像资料建立L1椎体的三维有限元模型,根据文献中椎体力学测试的力-变形曲线推算出骨质疏松症及骨折后的材料参数。然后分析骨质疏松症椎体、骨折后椎体以及椎体成形术中椎体植入骨水泥后的力学变化,探讨骨水泥的容量、位置对椎体蒙马氏应力及刚度的关系。第二是建立一个五节椎体模型来评价椎体成形术对邻近椎体的影响。结果分析结果得知,椎体植入骨水泥的容量越多,刚度增加越多;单侧(左侧、右侧、中间)与双侧植入骨水泥在同一植入骨水泥容量下差异无显著性意义(P>0.05)。结论若骨折后能矫正恢复原来的外形,则对邻近节段的影响并不大。Objective To use a validated finite element model to evaluate the effects of bone cement with different volumes and locations in vertebroplasty and the stress distribution of the vertebral bodies after vertebroplasty. Methods The study was performed in 2 stages. A finite element model of L1 was set up with the CT screenage data of the patients. The material parameters of osteoporosis and after fracture were calculated in the light of the force-deformity curve derived in the tests of vertebro-mechanics in the literature. The mechanical changes of osteoporosis vertebra, fracture vertebra and operated vertebra after the insertion of bone cement （PMMA） were measured and analyzed. Besides, we established another model with 5 motion segments to evaluate the effect of vertebroplasty on the adjacent vertebrae. Results According to our analysis, there was no significant difference between 6 mL, uni-pedicle and 10 mL, bi-pedicle models. The effect of 6mL, uni-pedicle model was similar to that of 6mL, bi-pedicle model and even better, but no significant difference was found. The effects were related to the volumes of bone cement, but not totally proportional to them. There were similar results between the same volumes but distributions were different （uni-pedicle, bi-pedicle） （P〉0.05）. Uni-pedicle approach seemed to be a safer method. Conclusion The results of the 5-level model show that there is no significant effect on adjacent vertebrae if the height of the injured vertebral body is recovered to the initial height.

关 键 词：椎体成形术 骨水泥 容量 生物力学 骨质疏松症 有限元分析 

分 类 号：R687.3[医药卫生—骨科学] R318.01[医药卫生—外科学]