过伸复位治疗胸腰椎单纯压缩性骨折的有限元分析

Hyperextension for the treatment of thoracolumbar spine compression fracture based on finite element method

背景:过伸复位被中医骨伤科临床广泛用于治疗胸腰椎单纯压缩性骨折,其生物力学机制研究尚显不足。目的:应用有限元分析方法探讨了复位过程中各结构的力学特性以及整体的应力特点。方法:依据1例T12椎体单纯压缩性骨折患者的210层Dicom3.0标准的CT图片建立T12椎体单纯压缩性骨折的有限元模型,在对建立的模型的有效性进行验证后模拟过伸复位手法,约束L2下端所有面,给T11椎体上端一个纵向牵引力,分别于T11,T12,L1椎骨棘突顶点给予一个方向垂直朝向椎体、大小为3.0cm的位移。程序运算后读取压缩椎骨外形改变和应力分布。结果与结论:建立了几何外型逼真、生物力学特性全面的胸腰段椎体压缩性骨折三维有限元模型,复位手法作用后压缩的椎骨表现出明显的过伸,在复位过程中表现的复位机制与传统的生物力学实验相同。利用有限元分析法研究传统手法的作用机制具有实验结果可靠、显示结果直观、节约资源以及手法模拟精确等优点,可广泛应用于骨折手法复位机制的研究。

BACKGROUND：Hyperextension is widely used to treat thoracolumbar spine compression fracture in clinical orthopedics by doctors of traditional Chinese medicine,but the research about the biomechanics is inadequate.OBJECTIVE：To probe the treatment mechanisms of thoracolumbar spine compression fracture by hyperextension based on finite element method.METHODS：A three-dimensional（3D） finite element model of compression fracture of T12 was established based on the 210-layer consecutive CT DICOM3.0 format images from one patient of compression fracture of T12.The effective of model was proved by simulating the hyperextension.The lower of T12 was bounded,a vertical traction at the top of T11 was imposed and a 3 cm-displacement toward the vertebral by three steps at the top of spinous process of T11,T12 and L1 was performed.The computing result about the shape and the stress of the model after the procedure computing were read.RESULTS AND CONCLUSION：A realistic appearance and full biomechanical properties 3D finite element model of thoracolumbar spine compression fracture was established.The shape of the compressed vertebrae was over extension by hyperextension.The treatment mechanisms were same as the research result of traditional experimental study on biomechanics.The method that study on mechanism of traditional practices by FEM is provided with many advantages,such as the experimental results are more reliable,showing the results intuitively,saving resources and simulating the practices accurately.The method may be applied comprehensively about fracture treatment mechanisms by manual reduction.