Microstructurally-based constitutive modelling of the skin - Linking intrinsic ageing to microstructural parameters

JOURNAL OF THEORETICAL BIOLOGY

卷:444

Article

Pond, D.¹  McBride, A. T.^1,2  Davids, L. M.³  Reddy, B. D.¹  Limbert, G.^4,5 

[1] Univ Cape Town, Ctr Res Computat & Appl Mech, Rondebosch, South Africa

[2] Univ Glasgow, Sch Engn, Glasgow G12 8QQ, Lanark, Scotland

[3] Univ Western Cape, Dept Med Biosci, Bellville, South Africa

[4] Univ Southampton, Fac Engn & Environm, Bioengn Sci Res Grp, Natl Ctr Adv Tribol Southampton, Southampton, Hants, England

[5] Univ Cape Town, Fac Hlth Sci, Dept Human Biol, Lab Biomech & Mechanobiol, Rondebosch, South Africa

关键词: Soft tissue;    Microstructure;    Anisotropy;    Collagen;    Elastin;    Bulge test;    Continuum mechanics;    Finite element method;   

DOI  :  10.1016/j.jtbi.2018.01.014

来源: Elsevier

【 摘 要 】

A multiphasic constitutive model of the skin that implicitly accounts for the process of intrinsic (i.e. chronological) ageing via variation of the constitutive parameters is proposed. The structurally-motivated constitutive formulation features distinct mechanical contributions from collagen and elastin fibres. The central hypothesis underpinning this study is that the effects of ageing on the mechanical properties of the tissue are directly linked to alterations in the microstructural characteristics of the collagen and elastin networks. Constitutive parameters in the model, corresponding to different ages, are identified from published experimental data on bulge tests of human skin. The numerical results demonstrate that degradation of the elastin meshwork and variations in anisotropy of the collagen network are plausible mechanisms to explain ageing in terms of macroscopic tissue stiffening. Whereas alterations in elastin affect the low-modulus region of the skin stress-strain curve, those related to collagen have an impact on the linear region. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

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