皮质骨轨迹椎弓根系统拔出力下腰椎的有限元分析  

Finite element analysis of lumbar vertebrae under the pull-out strength of screw in cortical bone trajectory technique

作　　者：任航宁 居来提·买提肉孜[1] 帕尔哈提·热西提[2] 罗辉卿 Ren Hangning;Jurat·Matrozi;Paerhati·Rexiti;Luo Huiqing(College of Mechanical Engineering,Xinjiang University,Urumqi 830047,Xinjiang Uygur Autonomous Region,China;The First Affiliated Hospital,Xinjiang Medical University,Urumqi 830047,Xinjiang Uygur Autonomous Region,China)

机构地区：[1]新疆大学机械工程学院,新疆维吾尔自治区乌鲁木齐市830047 [2]新疆医科大学第一附属医院,新疆维吾尔自治区乌鲁木齐市830047

出　　处：《中国组织工程研究》2021年第36期5771-5776,共6页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金地区基金项目(81960415),项目负责人:帕尔哈提·热西提,项目名称:腰椎改良皮质骨螺钉技术相关生物力学,3D导板设计与应用研究。

摘　　要：背景:椎弓根皮质骨螺钉内固定技术是目前临床治疗腰椎退行性疾病的主要手段,但传统皮质骨轨迹椎弓根方案置钉后螺钉存在很大的松动可能,进而引起固定失效或植骨不融合。目的:通过有限元方法比较腰椎在改良皮质骨轨迹椎弓根螺钉与传统皮质骨轨迹椎弓根螺钉固定技术应用下,受拔出力作用时的生物力学性能。方法:依据提取的骨质疏松症患者CT图像建立L1-L5全椎体功能单元骨质疏松人体有限元模型,模拟改良皮质骨轨迹椎弓根螺钉和传统皮质骨轨迹椎弓根螺钉两种固定方式置钉,在加载一定实际旋转拔出力状态下,测量两种方式钉道周围骨质的应力分布、最大应力值并分析其差异。结果与结论:(1)相同固定方式下相同载荷状态中,两种置钉方案中椎骨的应力分布差异明显,与传统皮质骨轨迹椎弓根组比,改良皮质骨轨迹椎弓根组的应力区体积及应力集中点明显减少,能显著增加置入螺钉的稳定性;(2)不同的钉道带来不同骨密度,直接影响了内固定螺钉在腰椎骨内的力学性能。(3)L1-L5椎体形状不同、大小不同,其力学性能、表现也不相同。可见改良的皮质骨轨迹椎弓根技术相比传统皮质骨轨迹椎弓根技术具有优越性,是骨质疏松患者腰椎内固定选择中的一种优选方式。BACKGROUND:Pedicle screw fixation is the preferred surgical treatment for clinical treatment of lumbar degenerative disease currently.However,there is a great possibility of screw loosening after the traditional cortical bone trajectory pedicle screw placement scheme,which may cause fixation failure or nonfusion of bone graft.OBJECTIVE:To compare biomechanical properties of novel cortical bone trajectory screw and cortical bone trajectory screw in lumbar vertebrae under pull-out strength by finite element method.METHODS:Based on the extracted computed tomography of patients with osteoporosis,the finite element model of L1-L5 full vertebral body functional unit osteoporosis was established.The novel cortical bone trajectory screw and cortical bone trajectory screw were simulated.The stress distribution and maximum stress value of bone around the screw track of the two methods were measured and compared under a certain actual rotation pull-out strength.RESULTS AND CONCLUSION:(1)Under the same fixation mode,the stress distribution of vertebrae in the novel cortical bone trajectory group and cortical bone trajectory group was significantly different under the same load state.Compared with cortical bone trajectory group,the volume of the stress zone and the stress concentration point were significantly reduced,which could significantly increase the stability of the inserted screw in the novel cortical bone trajectory group.(2)Different screw paths brought different bone mineral densities,which directly affected the mechanical properties of internal fixation screws in lumbar spine.(3)Different shapes and sizes of L1-L5 bone led to different mechanical properties and performance.It can be seen that the novel cortical bone trajectory technology has advantages over the cortical bone trajectory technology.The novel cortical bone trajectory technique is a preferred method for lumbar internal fixation in patients with osteoporosis.

关 键 词：腰椎 皮质骨轨迹椎弓根技术 双侧螺钉 应力分析 有限元 

分 类 号：R318.01[医药卫生—生物医学工程] R459.9[医药卫生—基础医学]