Wallis腰椎非融合系统的有限元分析  

Finite element analysis of Wallis non-fusion system for human lumbar

作　　者：刘瑞[1] 徐林[2] 张元智[1] 俞兴[2] 

机构地区：[1]内蒙古医学院附属医院骨科,内蒙古自治区呼和浩特市010050 [2]北京中医药大学东直门医院骨科中心,北京市100700

出　　处：《中国组织工程研究》2012年第13期2287-2291,共5页Chinese Journal of Tissue Engineering Research

基　　金：内蒙古自治区自然科学基金项目(2010MS1106);内蒙古自治区高等学校科学研究课题(NJ10132)资助~~

摘　　要：背景:目前Wallis非融合系统临床应用短期效果明显。目的:构建Wallis腰椎非融合系统有限元模型,分析Wallis腰椎非融合在腰椎不同生理运动情况下的应力分布。方法:选取8例腰椎间盘轻度退变的志愿者采用连续螺旋CT扫描,导入Materialise Mimics10.01软件,三维重建L4～5椎体及椎间盘三维模型,与文献结果进行对比,验证模型有效性。在AutoCAD2009软件中建立Wallis系统模型,导入Materialise3-Matic4.3软件,将重建的Wallis模型按标准手术模式与腰椎模型拟合,导入Abaqus6.9软件,生成有限元模型,并进行分析腰椎前屈、后伸、侧屈及旋转运动时Wallis腰椎非融合系统的应力变化。结果与结论:实验所建立的腰椎三维有限元模型共有233438个单元,48174个节点;所建立的Wallis系统的三维有限元模型,共有11857个单元,3398个节点,将二者拟合,模型共有245295个单元,51572个节点,重建的三维模型可以精确地模拟Wallis非融合系统固定情况。通过应力云图显示前屈、后伸、侧屈及旋转运动下Wallis系统的应力分布情况,此模型说明Wallis系统参与了腰椎不同方向的活动,与腰椎很好地匹配,顺应了腰椎的运动,位于上下棘突之间的部分应力较大,且与下位椎体棘突相接触部分的应力最高。说明应用CT扫描技术及Mimics软件能直接与Abaqus软件进行对接,并能根据CT值直接赋值使Wallis腰椎非融合系统有限元模型的建立更加快捷和精确,Wallis棘突间撑开器植入后可分担椎间盘应力和小关节压力,Wallis系统本身和棘突应力升高,有棘突骨折及植入物疲劳性断裂的可能性。BACKGROUND：At present,the clinical short-term effect of Wallis non-fusion system is obvious.OBJECTIVE：To establish the Wallis non-fusion system finite element model and to analyze the stress distribution under different physiological movement.METHODS：Eight volunteers with mild degeneration of the lumbar intervertebral disc were subjected to compute tomography（CT） scanner.CT scanning images were imported into Materialise Mimics 10.01 software.Three-dimensional models of L4-5 disc and its intervertebral disc were reconstructed,and then the results were compared with literature results to verify the model validity.Wallis system were established by using the AutoCAD 2009 software,and then transformed into Materialise 3-Matic 4.3 software for re-meshing,the reconstructed Wallis system was fitted with lumbar spine model according to the standard operation mode,and then transformed into Abaqus 6.9 software to form finite element model,then the stress changes of lumbar flexion,extension,lateral bending and rotation of lumbar Wallis non-fusion system were analyzed.RESULTS AND CONCLUSION：The three-dimensional finite element model of lumbar established in the experiment concluded 233 438 units and 48 174 nodes;the three-dimensional finite element model of Wallis system concluded 11 857 units and 3 398 nodes.After the two models were merged,it concluded 245 295 units and 51 572 nodes.The reconstructed three-dimensional model could accurately simulate the fixation of the Wallis non-fusion system.Then the stress changes of lumbar flexion,extension,lateral bending and rotation of lumbar Wallis non-fusion system were analyzed through stress contour.The stress contour showed that Wallis system was involved in the activities of lumbar spine in different directions and had a good match with the lumbar spine.Wallis system was conformed to the four movement conditions of lumbar spine,and the stress located between the upper and lower spinous part was more concentrated,and the stress contacted with the lower part of the ve

关 键 词：腰椎 WALLIS 非融合 有限元模型 生物力学 数字化骨科 

分 类 号：R318[医药卫生—生物医学工程]