有限元法分析寰-枢椎椎弓根螺钉内固定的生物力学变化  

Biomechanical changes of atlantoaxial pedicle screw-rod fixation: a finite element analysis

作　　者：陈树金 马向阳[1] 杨进城[1] 尹庆水[1] 杨敏[1] 邹小宝[1] Chen Shu-jin;Ma Xiang-yang;Yang Jin-cheng;Yin Qing-shui;Yang Min;Zou Xiao-bao(Department of Orthopedics,General Hospital of Guangzhou Military Command,Guangzhou 510010,Guangdong Province,China;Graduate School of Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China)

机构地区：[1]广州军区广州总医院骨科,广东省广州市510010 [2]广州中医药大学研究生院,广东省广州市510405

出　　处：《中国组织工程研究》2018年第31期4970-4974,共5页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金(81672232);广东省省级科技计划项目(2015B020233013)~~

摘　　要：背景:寰-枢椎椎弓根螺钉内固定系统已广泛应用于临床,尤其对于上颈椎病变同时伴有骨质疏松症患者,更加牢固可靠,但现阶段对于其生物力学方面的研究相对较少。目的:建立寰-枢椎椎弓根螺钉钉棒内固定三维有限元分析模型,分析其生物力学特性。方法:通过CT扫描获取一健康成年人枕骨、寰枢椎图像信息,构建寰-枢椎椎弓根螺钉钉棒内固定三维有限元分析模型,利用Abaqus加载前屈、后伸、左右侧弯、左右旋转等6种载荷,分析不同运动状态下内固定系统的应力变化。结果与结论:(1)寰-枢椎椎弓根螺钉钉棒内固定系统明显减少了上颈椎运动幅度,不同运动状态下,螺钉应力均主要集中在螺钉的钉-骨交界处及钉棒连接处;(2)前屈、左右侧弯、左右旋转状态下,枢椎椎弓根螺钉根部承受最大应力;(3)后伸状态下,寰椎椎弓根螺钉根部承受最大应力;(4)旋转状态下,螺钉与连接棒均存在明显的高应力区,螺钉及连接棒所承受应力最大值明显高于其他运动状态;(5)提示寰-枢椎椎弓根螺钉钉棒内固定安全可靠,螺钉进钉点根部周围易出现应力集中,旋转状态下,螺钉所受的应力明显增加。BACKGROUND:Atlantoaxial pedicle screw-rod fixation has been extensively applied in clinic,especially for upper cervical lesions with osteoporosis.But there are few biomechanical studies.OBJECTIVE:To investigate the biomechanical features of atlantoaxial pedicle screw-rod fixation by three-dimensional finite element analysis.METHODS:CT data of occipital bone and atlantoaxial vertebrae were obtained from a healthy adult volunteer,and the three-dimensional finite element analysis model of atlantoaxial pedicle screw-rod fixation was established.The changes of von Mises Stress of the internal fixation system under different loads(flexion,extension,left and right lateral bending,as well as left and right axial rotation by Abaqus)were analyzed.RESULTS AND CONCLUSION:(1)Atlantoaxial pedicle screw-rod fixation significantly reduced the motion range of upper cervical vertebra.(2)The stress concentrated on the bone-screw interface and screw-rod interface under different postures.The maximum stress located at the root of axoid pedicle screws under flexion,left and right lateral bending,as well as left and right axial rotation.(3)The maximum stress located at the root of atlas pedicle screws under extension.(4)Mises stress was obviously increased under rotation.(5)Atlantoaxial pedicle screw-rod fixation is safe and reliable.Stress concentration always appears at the root of screw and the Mises stress is increased obviously under rotation.

关 键 词：寰椎 枢椎 椎弓根螺钉 有限元 生物力学 国家自然科学基金 枢椎 有限元分析 生物力学 组织工程 

分 类 号：R318[医药卫生—生物医学工程]