骨盆及髋臼三维有限元模型材料属性设定及其生物力学意义

Biomechanical significance in the attribute selection of three dimensional fini te element model material of pelvis and acetabulum

目的:寻求骨盆及髋臼三维有限元模型构建中有限元模型材料属性设定的方法,并探讨相关的生物力学意义。方法:实验于2002-01/2004-04在第二军医大学长海医院骨科实验室和同济大学生命科学与技术学院生物力学实验室完成。通过计算骨盆及髋臼三维CT扫描层面上不同CT值,采用经典理论公式分析骨密度及骨骼弹性模量,最终确定有限元模型材料属性。结果:对于有限元模型材料属性,当Hu≤816时,ρα=1.9×10-3Hu+0.105,当Hu≥816时ρα=7.69×10-4Hu+1.028;而模型弹性模量则由E=3790ε0.06ρ3骨盆和髋臼三维有限元模型具体数值。结论:通过计算模型密度和弹性模量,进一步确定单元材料属性,对于建立接近实际的骨盆和髋臼三维有限元具有重要的意义。

AIM:To find out a selection method for attribute of finite element model mater ials in the construction of three dimensional finite element model of pelvis an d acetabulum so as to probe into its relative biomechanical significance. METHODS:The experiment was conducted in the laboratory of Department of Orthop aedics,Changhai Hospital Second Military Medical University of Chinese PLA and L aboratory of Biomechanics,College of Life Science and Technology,Tongjing Univer sity.The conventional theory formula was used for the analysis of bone mineral d ensity and skeletal elastic modulus to confirm the attribute of finite element m odel materials by using marching cube arithmetic to manage different CT image da ta matrix of pelvis and acetabulum scanned with three dimensional CT. RESULTS:To the attribute of finite element model material,when Hu≤816,ρα=1. 9×10-3 Hu+0.105,when Hu ≥816,ρα=7.69×10-4 Hu +1.028.The elastic modulus of model was the detailed data of three dimensional finite element model of pe lvis and acetabulum calculated with E=3 790ε0.06ρ3. CONCLUSION:The attribute of finite element model materials is confirmed farthe r by calculating density of model and elastic modulus,which is of important sign ificance to construct three dimensional finite element models close to the real ones.