摘要
目的构建出结构精细腰椎L3～S1三维有限元模型,计算ISOBAR TTL系统椎弓根钉、弹簧棒的应力分布、应力峰值并分析其对相邻节段的影响。方法一名26岁正常男性志愿者的CT图像,利用Mim-ics11.1、Geomagic studio10.0、HyperMesh 10.0和Abaqus6.8等软件建立L3~S1三维有限元模型,并验证其有效性,重建ISOBAR TTL术后模型,施加150 N预载荷及10 Nm力矩,模拟产生运动状态,计算椎间活动度、邻段椎间盘应力、内固定应力分布及应力峰值。结果成功建立L3~S1三维有限元模型;ISOBAR TTL系统应力主要分布在螺钉钉身处,应力峰值集中在螺钉中部,应力峰值不超过100MPa;对下腰椎整体活动度与无明显影响。结论 ISOBAR TTL系统能有效的维持术后腰椎活动度,减少应力遮挡,理论上可以减缓邻近节段的退变。
【Objective】 To establish finite element model of normal human lumbar spine（L3～S1） with fine anatomical structures and explore ROM of L3～S1,intra-diskal pressure of adjacent segment and the stress distribution and maximum value of the fixation devices during various motion conditions.【Methods】 The lumbar spine geometries were determined from CT images of a 26 year old healthy man.The finite element model（L3～S1） was constructed by the combination of software package Mimics 11.1,Geomagic studio10.0,HyperMesh 10.0 and Abaqus6.8.Inter-segmental ranges of motion was calculated after L3～S1 being subjected to loads of moments 10 Nm and 150 N preload and S1 was rigidly fixed while loads were applied at the L3 for flexion,extension,lateral bending and axial rotation.For validation of the model,their predicted inter-segmental range of motion was compared with the results by Yamamoto et al.【Results】 All the predicted responses of the final intact model were in good agreement with the published data by Yamamoto et al.All the screws have high stress concentration at the middle part of the screw.Maximal stress level of the fixation systems is all less than 100 MPa in different conditions.Compared to the reconstructed model by Isobar TTL,the total lumbar ROM of reconstructed models has no noticeable differences with the intact model.【Conclusion】 Isobar TTL system could maintain the entire ROM of L3～S1.It could be one of available treatment.
出处
《中国现代医学杂志》
CAS
CSCD
北大核心
2013年第12期101-104,共4页
China Journal of Modern Medicine
关键词
腰椎
动态固定
非融合
有限元分析
lumber vertebra
dynamic fixation
non-fusion
finite element analysis
