【摘要】 目的 运用有限元方法比较颈椎椎间孔螺钉（PVFS）、侧块螺钉（LMS）和椎弓根螺钉（PS）的生物力学强度。方法 采集1名22岁健康男性志愿者颈椎C₂～T₁ CT数据，应用有限元软件建立下颈椎(C_3～7)完整模型（对照组）以及C₅/C₆节段PVFS（PVFS组）、LMS（LMS组）和PS（PS组）内固定重建模型。在C₃上分别施加头颅载荷75 N，力矩为1 N/m，使模型产生前屈后伸、左右侧曲、左右旋转运动，计算各组C₅/C₆节段活动度（ROM）、螺钉应力及螺钉-骨界面应力。结果 实验建立了健康人下颈椎(C_3～7)有限元模型，共获得654 982个单元，869 841个节点，通过网格加密方法验证了本模型的有效性。PVFS组有限元模型获得639 846个单元，850 923个节点；LMS组有限元模型获得2 648 732个单元，859 105个节点；PS组有限元模型获得650 953个单元，861 843个节点。与对照组相比，6种工况下PVFS、LMS及PS组C₅/C₆节段ROM均降低：前屈（-66.9%,-56.2%,-72.8%），后伸（-53.3%,-49.4%,-63.9%），左侧曲（-60.2%,-55.3%,-64.9%），右侧曲（-61.7%,-57.3%,-65.8%），左旋（-38.8%,-35.4%,-49.1%），右旋（-41.7%,-37.9%,-51.4%）。在6种工况下PS组螺钉和螺钉-骨界面应力最小，PVFS组次之，LMS组最大。结论 与传统颈椎后路内固定方式相比，PVFS能够提供良好稳定性，可以作为后路内固定方式的一种补充。更多还原

【Abstract】 Objective To compare the biomechanical strength of cervical paravertebral foramen screws（PVFS）,lateral mass screws（LMS） and pedicle screws（PS） with finite element method.Method C₂-T₁ CT data was collected from a 22year old normal male volunteer,and to establish a complete model of the lower cervical spine(C_3-7)（control group）,as well as C₅/C₆ segment PVFS（PVFS group）,LMS（LMS group） and PS（PS group） internal fixation reconstruction models used finite element software.A head load of 75 N and a torque of 1 N/m on C₃ was applied to generate flexion and extension,left and right bending,left and right rotation movements in the model.The range of motion（ROM） of C₅/C₆ segment,screw stress and screw-bone interface stress under conditions of flexion and extension,left and right lateral bending,left and right rotation in each group were calculated.Results A finite element model of the lower cervical spine(C_3-7) in normal individuals was established,with a total of 654 982 elements and 869 841 nodes.The effectiveness of the model was verified through mesh refinement methods.The finite element model of PVFS group obtained 639 846 elements and 850 923 nodes,2 648 732elements and 859 105 nodes of LMS group,650 953 elements and 861 843 nodes of PS group.Compared with the control group,the ROMs of C₅/C₆ segment for PVFS,LMS and PS groups were decreased:flexion（-66.9%,-56.2%,-72.8%）,extension（-53.3%,-49.4%,-63.9%）,left bending（-60.2%,-55.3%,-64.9%）,right bending（-61.7%,-57.3%,-65.8%）,left rotation（-38.8%,-35.4%,-49.1%）,right rotation（-41.7%,-37.9%,-51.4%）.In terms of screw and screwbone interface stress,PS group was the least,followed by PVFS group,and LMS group was the largest under 6 conditions.Conclusion Compared with traditional posterior cervical fixation methods,PVFS can provide good stability,and can be used as a supplement method to posterior internal fixation.更多还原