不同角度置钉对胸腰椎骨折椎体生物力学稳定性的影响  

Effect of different angles of screw placement on biomechanical stability of thoracolumbar vertebral fractures

作　　者：崔晓兵[1] 刘霞 Cui Xiaobing;Liu Xia(Department of Imaging,Fourth People's Hospital of Hengshui,Hengshui 053000,Hebei,China)

机构地区：[1]衡水市第四人民医院影像科,衡水053000

出　　处：《脊柱外科杂志》2025年第1期29-34,共6页Journal of Spinal Surgery

基　　金：衡水市科技计划项目(2022014018Z)。

摘　　要：目的构建基于MRI影像特征的胸腰椎骨折有限元模型,并分析不同角度置钉对椎体生物力学稳定性的影响。方法基于2021年12月—2022年12月收治的3例胸腰椎骨折患者MRI影像特征,通过有限元软件构建胸腰椎骨折有限元模型,利用Hypermesh系统装配螺钉,以矢状面平行终板、斜向上终板7°、斜向下终板7°共3种角度置钉,模型施加载荷,模拟椎体在垂直、前屈、侧曲、后伸、旋转状态下的螺钉应力,比较5种状态下椎体的最大位移。另纳入同期收治的120例胸腰椎骨折患者影像学资料,依据矢状面椎弓根螺钉置入角度分为平行组(平行终板置钉)、向上组(斜向上终板置钉)、向下组(斜向下终板置钉)。记录患者术前、术后3个月胸椎侧凸Cobb角、胸椎后凸角、伤椎前缘高度比和伤椎后缘高度比。术后3个月采用Oswestry功能障碍指数(ODI)和日本骨科学会(JOA)评分评估腰椎功能。结果在各组模型中,椎体位移侧曲状态下最大,垂直状态下最小;在各运动状态下,椎体最大位移值平行组最大,向上组最小,组间比较差异有统计学意义(P<0.05)。3组患者术后3个月胸椎后凸角、胸椎侧凸Cobb角、伤椎前缘高度比、伤椎后缘高度比较术前明显降低,差异均有统计学意义(P<0.05)。向上组胸椎后凸角、胸椎侧凸Cobb角最小,伤椎前缘高度比、伤椎后缘高度比最高,与平行组、向下组比较,差异均有统计学意义(P<0.05)。向上组术后3个月ODI和JOA评分优于平行组和向下组,差异均有统计学意义(P<0.05)。结论斜向上终板置入椎弓根螺钉可有效提高骨折椎体稳定性,有助于术后脊柱功能的恢复,提高椎弓根螺钉内固定效果。Objective To construct a finite element model of thoracolumbar vertebral fractures based on MRI characteristics,and to analyze the effects of different angles of screw placement on the biomechanical stability of the vertebral body.Methods Based on the MRI characteristics of the 3 patients with thoracolumbar vertebral fractures from December 2021 to December 2022,a finite element model of the thoracolumbar vertebral fracture was constructed using finite element software.The Hypermesh system was used to assemble screws,and the screws were placed at 3 angles:upward endplate 7°,parallel endplate,and downward endplate 7°in the sagittal plane.The model applied loads to simulate the screw stress of the vertebral body in vertical,flexion,lateral bending,extension,and rotation states,and compared the maximum displacement of the vertebral body in 5 states.Reviewing and analyzing the imaging data of 120 patients with thoracolumbar fractures during the same period,they were divided into 3 groups based on the angle of pedicle screw placement:parallel group(parallel endplate placement),upward group(upward endplate placement),and downward group(downward endplate placement).The Cobb angle of thoracic scoliosis,thoracic kyphosis angle,anterior height ratio of injured vertebra,and posterior height ratio of injured vertebra at pre-operation and postoperative 3 months were recorded.The Oswestry disability index(ODI)and Japanese Orthopaedic Association(JOA)score were used to evaluate the lumbar function at postoperative 3 months.Results In each group of models,the displacement of the vertebral body was the largest in the lateral bending state,and the smallest in the vertical state.In each movement state,the maximum displacement of vertebral body in the parallel group was the highest,and the upward group was the smallest,and the differences were statistically significant(P<0.05).At postoperative 3 months,the thoracic kyphosis angle,Cobb angle of thoracic scoliosis,anterior height ratio of injured vertebra,and posterior height ratio

关 键 词：胸椎 腰椎 脊柱骨折 骨钉 生物力学 

分 类 号：R683.2[医药卫生—骨科学]