Harrigan T P, Jasty M, Mann R W, Harris W H
Department of Mechanical Engineering, Massachusetts Institute of Technology.
J Biomech. 1988;21(4):269-75. doi: 10.1016/0021-9290(88)90257-6.
Most existing stress analyses of the skeleton which consider cancellous bone assume that it can be modelled as a continuum. In this paper we develop a criterion for the validity of this assumption. The limitations of the continuum assumption appear in two areas: near biologic interfaces, and in areas of large stress gradients. These limitations are explored using a probabilistic line scanning model for density measurement, resulting in an estimate of density accuracy as a function of line length which is experimentally verified. Within three to five trabeculae of an interface, a continuum model is suspect. When results as predicted using continuum analyses vary by more than 20-30% over a distance spanning three to five trabeculae, the results are suspect.
大多数现有的考虑松质骨的骨骼应力分析都假定其可被建模为连续体。在本文中，我们制定了一个关于该假设有效性的标准。连续体假设的局限性体现在两个方面：靠近生物界面处以及大应力梯度区域。利用用于密度测量的概率线扫描模型对这些局限性进行了探究，得出了作为线长函数的密度精度估计值，并通过实验进行了验证。在界面的三到五个小梁范围内，连续体模型值得怀疑。当使用连续体分析预测的结果在跨越三到五个小梁的距离上变化超过20% - 30%时，结果就值得怀疑。
