Pewien model mechaniczny kręgosłupa lędźwiowo-krzyżowego człowieka

To answer a question whether common disorders of the low lumbar vertebrae can be caused or developed by mechanical factors, authors analysed loads and stresses acting on human lumbar vertebrae using modelling methods. Simplified mechanical model was the first step to construct a mathematical model. Results of analysis of the mathematical model (forces acting on lumbar vertebrae) were used to load the three dimensional photoelastic model of a part of human lumbar spine. Two different photoelastic methods: thin slices mathod to find stresses concentrations and small cubes method to find effective stresses according to criterion of Huber-von Mises, showed results which are in good agreement with modes of damage of real vertebrae. The investigations presented in the paper have shown that mechanical factors can not be neglected in pathogenesis of the human lumbar spine.