摘要
针对去软组织骨生物力学建模问题,采用有限元仿真手段通过股骨CT体数据集三维几何重建、网格划分、股骨表观密度计算、有限元单元横观各项同性力学模型建立、力学参数确定等几个步骤实现对股骨的力学建模和解算。其中,最关键的工作是力学参数确定,尤其是弹性模量和表观密度关系式的建立。依据胞元理论建立了弹性模量和表观密度的分段函数关系,最终获得股骨力学模型并通过仿真计算得到载荷-轴向应变和载荷-横向应变数据。同时,也基于弹性模量和表观密度经验关系式建立力学模型并进行分析计算提取仿真结果,通过实施生物力学试验提取试验结果,将两种仿真结果与试验结果对比得出:同一块猪股骨,在相同力学环境下,胞元理论力学模型与试验结果轴向应变误差为25.92,横向应变误差为10.04,两种误差均小于经验公式力学模型仿真结果误差,因此,胞元理论力学模型在股骨建模中表现出模型更精确、适用范围更广泛的优势。
Aimed to modeling bone biomechanics removed from soft tissue, model is analyzed by using finite element method. The process of fresh swine thighbone biomechanical modeling include 3D geometry reconstruction of femoral CT image data, grid, determination of apparent density, transverse isotropic mechanical modeling of finite element and parameter selection of biomechanical model. Parameters selecting is the key work in this process. Specially, relational model between elastic modulus and apparent density is the most important step. A defined function model between elastic modulus and apparent density is developed based on cellular theory. Then load-axial strain and load-lateral strain data are got from mechanical model analysis results of femur. Finite element analysis results from empirical formula of elastic modulus and apparent density also are got and biomechanical test data are recorded. Simulation results from two kinds of models are compared to test results. To the one fresh swine thighbone, Under the same environment, the result of contrast show axial strain error between cellular theory mechanical model and test data is 25.92, lateral error is 10.04. Cellular theory mechanical model simulation results are more similar to test data than results from empirical formula mechanical model. Cellular theory mechanical model show clear advantage in accurate and scope of application for femoral modeling.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2015年第11期142-149,共8页
Journal of Mechanical Engineering
基金
国家自然科学基金(61272387)
教育部新世纪人才(NCET-13-0756)
黑龙江省杰出青年基金(JC201302)资助项目
关键词
胞元理论
经验公式
骨组织建模
生物力学
模型评价
cancellular theory
empirical model
bone tissue modeling
biomechanics
model evaluation
