骨组织力电效应的生物力学模型和有限元分析

Biomechanical model and finite element analysis on electromechanical behaviours in bone tissues

目的:运用数值研究的方法阐述骨组织应力对流动电位的影响,为阐明骨生理、病理现象以及进一步研究骨损伤相关疾病辅助物理康复技术奠定理论基础.方法:将骨组织看作是一种由固体骨基质和细胞外液等液体所组成的两相多孔介质模型,结合电动理论,建立描述骨组织的生物力学模型以及流动电位的模型,由Galerkin加权残值法和罚方法得到了有限元方程.通过自编程序对骨组织的变形场、流动场和流动电位进行了数值分析和模拟,并与实验进行了对比观察.结果:得到了流动电位与载荷频率、载荷大小的关系.结论:流动电位随载荷频率单调增加,并且其斜率逐渐减少,最后流动电位趋向于平缓.流动电位与驱动载荷的相位差跟载荷频率的关系刚好和幅值变化相反,随载荷频率的升高,相位差减少.

AIM：Based on researching the relationship of stress and streaming potential in bone tissues by numerical methods,biomechanical properties of bone can be understood.And physiological and pathological phenomenon can be explained.There is important significance on auxiliary physical rehabilitation techniques researching for treatment of bone fracture and related diseases.METHODS：Upon physiological structure of bone tissue,the porous media theory associated with electro-kinetics was used to model the electromechanical effects in bone tissue.The finite element governing equations were built up through Galerkin method and the penalty method.The distortion of skeleton,interstitial fluid flow and the streaming potential in bone tissue were numerically computed and simulated.Then the results will be compared with experiments.RESULTS：The relationship of streaming potential and frequency and magnitude of loading is gained.CONCLUSION：The magnitude of streaming potential is increasing with the loading frequency,and the slope is declining.The relations of the phase difference of streaming potential and load is just opposite with amplitude changing.The phase difference is declining with the loading frequency increasing.