有限元骨承载力分析法与壁厚分析法预测骨愈合程度的比较研究  

A comparative study on prediction of bone healing by finite element analysis between bone bearing capacity and wall thickness

作　　者：童梁成 杨智伟 汪剑龄 杨俊生 徐俊捷 许建辉 李颖 TONG Liang-cheng;YANG Zhi-wei;WANG Jian-ling;YANG Jun-sheng;XU Jun-jie;XU Jian-hui;LI Ying(Department of Orthopedics,Air Force Hospital of PLA Eastern Theater Command,Nanjing,Jiangsu 210002,China;不详)

机构地区：[1]中国人民解放军东部战区空军医院骨科,江苏南京210002 [2]三的部落(上海)科技股份有限公司,上海200230

出　　处：《中国骨与关节损伤杂志》2021年第10期1035-1039,共5页Chinese Journal of Bone and Joint Injury

基　　金：原南京军区医学科技创新项目(15DX012);南京市医疗卫生科技计划项目(201503008)。

摘　　要：目的建立下肢长骨干有限元分析模型,比较有限元骨承载力分析法与壁厚分析法预测下肢长骨干骨愈合程度的效果。方法收集4例临床诊断为下肢长骨干骨折不愈合患者的CT扫描数据,建立有限元分析模型,分别采用有限元骨承载力分析法和壁厚分析法进行二次模拟仿真计算,共进行8次分析。骨承载力分析法通过有限元分析得出健侧与患侧应力-应变曲线,利用GraphPad计算曲线下总面积进行比值分析。壁厚分析法通过判读骨皮质壁厚薄弱区的情况,通过材料密度与刚度转化关系对最大壁厚分值进行比值分析。结果 4例临床诊断均为骨折不愈合,骨承载力法修正诊断结果为2例骨折愈合,2例骨折延迟愈合,内固定均有效;壁厚分析法修正诊断结果为3例骨折愈合,1例骨折延迟愈合,内固定均有效。ROC曲线分析结果显示,有限元骨承载力分析更加接近骨真实情况并且敏感性更好,有限元壁厚分析对判定骨愈合的特异性更高。结论骨承载力分析法能更好地模拟目标骨段的真实载力环境,但是计算过程中软件切换次数较多,结果飘移度较大。壁厚分析法省略了赋值和载力环境的调试过程,在同一个软件下分析骨愈合过程中骨痂变化情况,能够更有效预测骨愈合程度。ObjectiveTo establish a finite element analysis model of lower limb long bone, and to compare the effect of finite element bone bearing capacity analysis and wall thickness analysis for predicting the healing degree of lower limb long bone.MethodsThe CT data of 4 patients with nonunion of long shaft fractures of lower extremities were collected, and the finite element analysis model was established. The finite element bone bearing capacity analysis method and wall thickness analysis method were used for secondary simulation calculation, and a total of 8 times of analysis were carried out. In the analysis of bone bearing capacity, the stress-strain curves of the healthy side and the affected side were obtained by finite element analysis, and the ratio of the total area under the curve was calculated by GraphPad. The wall thickness analysis method interpreted the weak area of bone cortical wall thickness and analyzed the ratio of the maximum wall thickness score through the transformation relationship between material density and stiffness.ResultsAll the 4 cases were clinically diagnosed as nonunion. By bone bearing capacity method, the diagnosis was modified as fracture union in 2 cases and delayed union in 2 cases, all the internal fixation was effective while by wall thickness analysis, the diagnosis was modified as fracture union in 3 cases and delayed union in one case, all the internal fixation was effective. The results of ROC curve analysis showed that the finite element analysis of bone bearing capacity was closer to the real situation of bone and had better sensitivity, and the finite element analysis of wall thickness was more specific in judging bone healing.ConclusionThe bone bearing capacity analysis method can better simulate the real load environment of the target bone segment, but there are more software switching times in the calculation process,resulting in a larger degree of drift. The wall thickness analysis method omits the debugging process of assignment and load environment, and analyzes the

关 键 词：骨生物力学 有限元分析法 壁厚分析法 骨愈合 骨承载力 骨强度 骨密度 CT灰度值 

分 类 号：R687.3[医药卫生—骨科学]