Influence of Stratum Corneum on the entire skin mechanical properties, as predicted by a computational skin model.

Background/Purpose: Skin mechanical properties are globally well described. The aim of this paper is to evaluate, by means of a numerical model, the influence of Stratum Corneum (SC) on skin folding resulting from an in-plane compression. Methods: A computational skin model was developed where skin is divided into three layers (SC, epidermis and upper dermis, and deep dermis) of different thicknesses and elastic moduli. Skin surface deformation, consecutive to the application of a given surface compression, was computed by minimizing the mechanical energy of the multi-layered tissue. Influence of SC thickness and elastic modulus on skin buckling is presented. Results: Varying both SC thickness and elastic modulus has a marked influence on both wavelength and amplitude of the skin's surface folds. These two parameters display a logarithmic variation versus SC elastic modulus. Conclusion: Although representing about one hundredth of the total skin thickness, SC has a marked influence on the skin mechanical properties.