摘要
目的应用三维有限元分析评价镁合金与钛合金制备的经口咽前路寰枢椎复位内固定钢板（transoralpharyngeal atlantoaxial reduction plate，TARP）系统治疗寰枢椎脱位后的生物力学性能，测试镁合金材料制备TARP系统的可行性，为临床手术治疗提供理论依据。方法选择1例典型寰枢椎骨折脱位患者，并与临床已经应用的钛合金材料制备的TARP系统进行CT薄层扫描，获得DICOM图像数据。导人三维有限元分析软件，分别模拟使用钛合金与镁合金两种不同材料制备TARP系统进行复位与内固定，应用三维有限元分析法计算两种不同材料内固定后寰椎、枢椎、内固定材料以及C2/3，的关节突关节应力变化，并进行统计学分析。结果（1）所建寰枢椎脱位复位与内固定有限元模型几何相似性好，共包含53586个节点、180784个单元；（2）在模拟头颅位于中立时，应力集中区域分别为C2/3关节突，其次是寰椎前弓、后弓和侧块；再次为C2椎弓；（3）镁合金和钛合金两种材料制备的TARP系统，在相应的力学分布上差异有统计学意义（P〈0．05）结论（1）应用CT扫描获取寰枢椎空间结构信息建立的寰枢椎模型可用于生物力学试验；（2）采用现有的钛合金TARP系统治疗寰枢椎脱位，保持寰椎前弓、后弓完整，侧块处植骨融合确实，可以更好保持寰枢椎的稳定性；寰枢椎融合后，相邻节段的关节突受力增加，加速退变，应密切随访；（3）相对于钛合金TARP，采用镁合金材料制备TARP系统进行复位固定，前述应力集中区域的峰值降低，应力分布均匀性提高。
Objective To evaluate biomechanical properties of transoralpharyngeal atlantoaxial reduction plate （TARP） prepared from magnesium alloy and titanium alloy for the atlantoaxial dislocation by using three-dimensional finite element analysis and to exam the feasibility of using magnesium alloy for preparation of TARP system so as to provide a theoretical basis for clinical surgery. Methods A pa- tient with typical atlantoaxial fracture dislocation was involved in the study, and received thin CT scan with clinically used titanium alloy TARP system for obtaining DICOM image data. Three-dimensional fi- nite element analysis software was imported to simulate magnesium alloy and titanium alloy TARP systems for reduction and fixation. Then, stress changes of the atlas, axis, internal fixators and C~/3 zygapophysial joints were determined with three-dimensional finite element analysis and analyzed statistically. Results （ 1 ） The finite element model of atlantoaxial dislocation reduction and fixation had lifelike outline and good geometric similarity. There were 53 586 nodes and 180 784 units. （2） During the simulation of head in neutral position, the stress concentration region was C2/3 zygapophysial joints followed by the anterior arch, posterior arch and lateral mass of atlas respectively, and C2 vertebral arch again. （ 3 ）Magnesium alloy and titanium alloy TARP systems showed significant difference in stress distribution （P 〈 0.05）. Conclusions （ 1 ） The atlantoaxial model established according to its structure information on CT can be used for biomechanieal experiments. （2） For the treatment of atlantoaxial dislocation using the existing titanium TARP system, maintaining the integrity of anterior and posterior arch of atlas and confirming the bone fusion in lateral mass can better keep the stability of the atlantoaxis. After atlantoaxial fusion, the increased stress of the zygapophysial joints of the adjacent segments accelerates structural degeneration, which should be closely followed up. （3） Magnesium alloy TARP system for fixation and reduction shows the fall in peak value of the stress concentration region, and improvement of the uniformity of stress distribution as compared with titanium alloy TARP.
出处
《中华创伤杂志》
CAS
CSCD
北大核心
2012年第10期921-925,共5页
Chinese Journal of Trauma
基金
全军医学科研“十二五”重点资助项目（bws11c065）
全军医学科研“十二五”面上资助项目（cws11c268）
全军热区创伤救治与组织修复重点实验室项目
关键词
脊柱损伤
寰椎
枢椎脱位
有限元分析
合金
Spinal injuries
Atlas
Axial dislocation
Finite element analysis
Alloys
