Studying the Mechanical Behavior of Tissue in the Generation of Pressure Sores using Simulation and a Guinea Pig Experimental Model

Abstract

Introduction: Pressure sores refer to lesions that are produced while a constant pressure causes necrotic <br/>tissue to grow. The need for a better comprehension of the process has led researchers to artificial generation <br/>of pressure sores. Modeling the mechanical behavior of tissue will provide a better understanding of this <br/>process as well as a more suitable selection of system parameters. <br/>Materials and Methods: In this research, the mechanical behavior of tissue was modeled using the finite <br/>element method. A system with pressure sensors and a suitable feedback mechanism was used to generate <br/>pressure sores. The elastic parameters of tissue were obtained using uniaxial tensile strength tests. The <br/>thicknesses of skin layers were calculated by taking microscopic images of skin samples and using Motic <br/>Images 2000 version 1.2 software. <br/>Results: The results of the finite element modeling illustrate the strain and stress profiles in tissue layers. The <br/>maximum values of deviatory strain occurred under the border of the disc in the muscle layer. Deviatory and <br/>shear stresses reached their maximum values under the center of the disc in the skin layers. <br/>Discussion and Conclusion: The simulation and experimental results are in good agreement. Therefore, the <br/>introduced model may be used for better comprehension of tissue behavior. Better results may be obtained by <br/>finding a more accurate method for calculating tissue parameters.