颈椎前路融合手术中钢板摆放角度对颈椎稳定性影响的有限元分析

目的:利用有限元分析的方法,比较颈前路融合手术中钢板偏离颈椎长轴与钢板标准摆放的生物力学性能.方法:选取一名健康女性志愿者并进行CT扫描(C1-T1),应用Mimics 19.0,Geomagic Studio 2015,Solidworks 2018,Ansys Workbench 17.2等软件建立下颈椎(C3-C...

Finite element analysis of the effect of plate placement angle on cervical spine stability in anterior cervical fusion surgery

Objective: Using the method of finite element analysis,to compare the biomechanical properties between the plate deviating from the long axis of the cervical spine and the standard placement of the plate in the anterior cervical fusion surgery. Methods: A healthy female volunteer was selected and CT scan (C₁-T₁) was performed. Using Mimics 19.0,Geomagic Studio 2015,Solidworks 2018,Ansys Workbench 17.2 to establish a lower cervical spine (C₃-C₇) model and to verify the reliability of the model. Subsequently,anterior cervical plates of different angles and lengths were placed to establish an anterior cervical discectomy fusion(ACDF) model. Applying 73.6 N axial pressure and 1 NM pure moment on C₃ to make the model produce flexion,extension,lateral bending and rotation activities,observed the model stress cloud diagram and recorded the maximum stress value of the instrument and the intervertebral mobility. Results: The lower cervical spine(C₃-C₇) finite element model was established and verified against the published literature on the range of motion (ROM) of cervical spine. Effect of steel plate offset axis on stress distribution,maximum stress value and intervertebral ROM of internal fixation apparatus was minimal,and the mechanical effect of steel plate offset was less in double section steel plate than in single section steel plate. Conclusion: Little effect on the mechanical stability of the cervical spine was anticipated when the anterior cervical plate was not perfectly aligned with the long axis of the cervical spine. If the tilt of the plate in clinical surgery is less than 20°,there is no need to readjust the position of the plate.