人体腰椎活动节段应力分布的实验研究

本文采用三维光弹性实验方法观察了正常腰椎活动节段的应力分布。用精密浇铸,严格几何相似的光弹性环氧树脂腰椎和硅橡胶椎间盘模型进行三维光弹性实验,并观察腰椎的等应力差图和有效应力值分布。本实验观察到,腰椎椎体上下缘应力分布较均匀对称,其后缘应力大于前缘,后部结构应力较小。作者认为,三维光弹性实验方法具有直观性强,能有效和准确地确定腰椎的应力分布,对腰椎生物力学研究具有重要的实用价值。腰椎后缘应力大于前缘,使椎体后缘承载较大,将会增加腰椎间盘退变和损伤的机会,这可能是引起腰腿痛的重要因素。

Stress Distribution of Functional Segment of Human Lumbar Spine: A Photoelastic Experiment

Stresses of human lumbar spine functional segments were investigated using the three-dimensional photoelastic experiment. Photoelastic models were made of epoxy resin and silicon rubber. Isochromatic fringes and effective stresses were observed. The results showed that the posterior parts of vertebrae are subjected to the highest mechanical stresses among the elements of lumbar spine. The authors believe that the photoelastie experiment can be used to determine the effective stress and stress conintensity precisely. High mechanical stress in the posterior parts of vertebrae may cause the degenerative change and injury of the intervertebral disc which may be one of the important factors of lumbago.