Jayyosi C, Affagard J-S, Ducourthial G, Bonod-Bidaud C, Lynch B, Bancelin S, Ruggiero F, Schanne-Klein M-C, Allain J-M, Bruyère-Garnier K, Coret M
IFSTTAR, UMR_T9406, LBMC, Univ Lyon, Université Claude Bernard Lyon 1, F69622, Lyon, France.
LMS, Ecole Polytechnique, CNRS, Université Paris-Saclay, Palaiseau, France.
Biomech Model Mechanobiol. 2017 Aug;16(4):1459-1473. doi: 10.1007/s10237-017-0899-1. Epub 2017 Mar 29.
The affine transformation hypothesis is usually adopted in order to link the tissue scale with the fibers scale in structural constitutive models of fibrous tissues. Thanks to the recent advances in imaging techniques, such as multiphoton microscopy, the microstructural behavior and kinematics of fibrous tissues can now be monitored at different stretching within the same sample. Therefore, the validity of the affine hypothesis can be investigated. In this paper, the fiber reorientation predicted by the affine assumption is compared to experimental data obtained during mechanical tests on skin and liver capsule coupled with microstructural imaging using multiphoton microscopy. The values of local strains and the collagen fibers orientation measured at increasing loading levels are used to compute a theoretical estimation of the affine reorientation of collagen fibers. The experimentally measured reorientation of collagen fibers during loading could not be successfully reproduced with this simple affine model. It suggests that other phenomena occur in the stretching process of planar fibrous connective tissues, which should be included in structural constitutive modeling approaches.
在纤维组织的结构本构模型中，通常采用仿射变换假设来将组织尺度与纤维尺度联系起来。由于成像技术的最新进展，如多光子显微镜，现在可以在同一样本内不同拉伸情况下监测纤维组织的微观结构行为和运动学。因此，可以研究仿射假设的有效性。在本文中，将仿射假设预测的纤维重新定向与在皮肤和肝包膜力学测试期间获得的实验数据进行比较，这些实验数据是通过多光子显微镜结合微观结构成像获得的。在增加加载水平时测量的局部应变值和胶原纤维取向用于计算胶原纤维仿射重新定向的理论估计值。用这个简单的仿射模型无法成功再现加载过程中实验测量的胶原纤维重新定向。这表明在平面纤维结缔组织的拉伸过程中发生了其他现象，这些现象应纳入结构本构建模方法中。
