一种新型颈椎前路可固定式钛笼三维有限元模型的建立

Establishment of 3D finite element model of a new type of fixable titanium mesh cage for anterior cervical vertebra

目的:基于人体C4~C6节段椎体次全切除术(ACCF),应用一种新型颈椎前路可固定式钛笼,建立三维有限元仿真分析模型。方法:获得健康男性颈椎薄层CT图像,利用Mimics软件进行颈椎骨性结构三维重建,导入3-Matics软件进行模型修补,补充结构,利用Ansys软件完成有限元模型的建立。计算正常颈椎模型各节段的运动范围,与文献数据进行对比以验证其有效性,并模拟颈椎椎体次全切除术式,将新型钛笼模型添加到减压区,建立C5节段ACCF钛笼固定有限元模型。结果:建立的正常颈椎C4~C6节段钛笼三维有限元模型各节段的运动范围与既往文献研究结果近似;对ACCF术式有限元模型进行静态力学分析,获得钛笼与相邻椎体表面等效应力值。结论:新型钛笼三维有限元模型的设计,对于降低钛笼沉降可起到积极作用,该模型与实体标本具有较好的相似性,可用于术式模拟和后续实验研究,并为颈椎内固定器械的设计提供技术支持。

Objective: To establish a three-dimensional (3D) finite element simulation analysis model based on anterior cervical corpectomy and fusion (ACCF) of C4-C6 segment of human body and on the application of a new type of fixable titanium mesh cage for anterior cervical vertebra. Methods: Through obtained CT images of thinslice of cervical vertebrae of healthy males, and used Mimics software to reconstruct 3D bony structure of cervical vertebrae. And then, the model was modified and its structure was supplemented by 3-Matics software. And the finite element model was established by Ansys software. Through calculated range of motion (ROM) of each segment of normal cervical vertebra model and compared it with the data in the literature to verify its validity. And ACCF was simulated. The new type of titanium mesh cage model was added to the decompression zone so as to establish the fixed finite element model of titanium mesh cage of ACCF of C5. Results: The ROM of each segment of 3D finite element model of titanium mesh cage of normal cervical C4-C6 was similar to that of the results of literature. Through the implemented static mechanical analysis of ACCF finite element model, the equivalent stress value of titanium mesh cage with adjacent vertebral surface was obtained. Conclusion: The design of 3D finite element model of the new type of titanium mesh cage may play a positive role in reducing the sedimentation of titanium mesh cages. The model has good similarity with the specimens of entity. And it can be used for surgical simulation and subsequent experimental research, and it can provide technical support for the design of internal fixation instruments of cervical vertebra.