Finite element modelling vs. classic beam theory: comparing methods for stress estimation in a morphologically diverse sample of vertebrate long bones

Classic beam theory is frequently employed in biomechanics to model the stress behaviour of vertebrate long bones, particularly when creating intraspecific scaling models. Although methodologically straightforward, classic beam theory requires complex irregular bones to be approximated as slender beams, and the errors associated with simplifying complex organic structures to such an extent are unknown. Alternative approaches, such as Finite Element Analysis (FEA), whilst much more time-consuming to perform, require no such assumptions. This paper compares the results obtained using classic beam theory with those from FEA to quantify the beam theory errors and to provide recommendations about when a full FEA analysis is essential for reasonable biomechanical predictions. High-resolution computed tomographic (CT) scans of eight vertebrate long bones were used to calculate diaphyseal stress due to various loading regimes. Under compression, FEA values of minimum principal stress (σ_min) we...

经典梁理论在生物力学领域被广泛用于模拟脊椎动物长骨的应力行为，在构建种内缩放模型时尤为常用。尽管该方法原理较为简洁，但经典梁理论需要将复杂不规则的骨骼近似为细长梁，而将复杂有机结构如此简化所带来的误差尚未明确。替代方案如有限元分析（Finite Element Analysis，FEA），虽执行耗时显著更长，却无需作出此类假设。本文对比了经典梁理论与有限元分析的结果，以量化梁理论的误差，并为判断何时需开展完整的有限元分析以获得合理的生物力学预测提供建议。研究采用8例脊椎动物长骨的高分辨率计算机断层扫描（CT）数据，计算了不同加载工况下的骨干应力。在压缩工况下，有限元分析得到的最小主应力（σ_min）数值……