基于正常人体资料建立胸腰椎单椎体压缩骨折三维有限元模型的方法与意义

Method and clinical significance of reconstructing a threedimensional finite element model of human thoracolumbar spine compression fracture based on information from normal human

目的探讨基于正常人体资料建立胸腰段脊柱椎体压缩性骨折三维有限元模型的方法及临床意义。方法将健康志愿者扫描所得的胸腰段210层Dicom格式CT图像直接读入Mimics后,界定骨组织阈值、提取各层面轮廓线、图像边缘分割、选择性编辑及补洞处理去除冗余数据,三维化处理后获得胸腰段三维几何面网格模型,直接导入Ansys划分体网格,再将体网格转入Mimics并根据CT值给予赋值,再次导入Ansys添加韧带、关节约束后生成三维有限元模型。在生成的模型上约束T12下端、在其上缘由前向后施加位移载荷,运算求解。将单纯T12椎体压缩性骨折患者的CT扫描图片按同法建立有限元模型,并将两骨折模型施加压力验证其有效性。结果建立了外形逼真、生物力学特性全面的胸腰段脊柱椎体压缩性骨折三维有限元模型。结论应用正常人体原始资料依据骨折受伤机制构建相应骨折有限元模型的方法科学有效。

【Objective】 To explore the method and clinical significance of reconstructing a three-dimensional finite element model of human thoracolumbar spine compression fracture based on information from normal human.【Methods】The 210-layer consecutive CT DICOM format images of thoracolumbar bodies in the healthy volunteers were directly read into the Mimics.Bone organization threshold was defined.Each outline was drawn.Each edge of layer picture was partitioned,selectively edited and repaired by hole processing.After the redundancy data were cleaned,the thoracolumbar 3D finite element geometry model was acquired.Then area mesh was directly introduced into Ansys software to mesh body,and then the body mesh was transferred to mimics to give evaluation on the basis of CT values,then the ligaments and joint-bindings were added to perfect the 3D finite element model in Ansys.Then the lower end was bound and displacement-load was imposed in the upper edge of T12.A three-dimensional finite element model was reconstructed using CT images from a patient of T12 vertebral compression fracture.The effectiveness of the two fracture-model was verified by imposing load.【Results】 A 3D finite element model of thoracolumbar spine compression fracture was established with realistic appearance and full biomechanical properties.【Conclusion】The method of reconstructing a three-dimensional finite element model of human thoracolumbar spine compression fracture based on fracture mechanism by information from normal human is scientific and effective.