A biomechanical model of the human stomach is proposed, that is based on detailed biological data of the structure and function of the organ. The process of electromechanical conjugation and the spread of the electromechanical wave along the stomach wall were analyzed numerically. Results revealed patterns of stress-strain distribution in the organ. Thus the fundus, the body and the antrum of the organ always experience biaxial stress-strain states, while the cardia and the pylorus undergo uniaxial loading. The circular smooth muscle layer produced greater total forces throughout in comparison to the outer longitudinal smooth muscle layer. The body of the organ along the lesser curvature and the cardia-fundus areas were overstressed compare to other regions. Although the theoretical results resemble qualitatively patterns of electrical and mechanical activity observed in vivo and in vitro there is currently no affirmative experimental evidence to provide a detailed quantitative comparison of the results.
mathematical model, human stomach, numerical simulations, electromechanical activity, peristalsis
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