Department of Anatomy, University of Otago, Dunedin, New Zealand.
Institute of Materials Science and Engineering, Chemnitz University of Technology, Chemnitz, Germany.
Sci Rep. 2019 May 27;9(1):7887. doi: 10.1038/s41598-019-44306-z.
Though it is known that the water content of biological soft tissues alters mechanical properties, little attempt has been made to adjust the tissue water content prior to biomechanical testing as part of standardization procedures. The objective of this study was to examine the effects of altered water content on the macro and micro scale mechanical tissues properties. Human iliotibial band samples were obtained during autopsies to osmotically adapt their water content. Macro mechanical tensile testing of the samples was conducted with digital image correlation, and micro mechanical tests using atomic force microscopy. Analyses were conducted for elastic moduli, tensile strength, and strain at maximum force, and correlations for water content, anthropometric data, and post-mortem interval. Different mechanical properties exist at different water concentrations. Correlations to anthropometric data are more likely to be found at water concentrations close to the native state. These data underline the need for adapting the water content of soft tissues for macro and micro biomechanical experiments to optimize their validity. The osmotic stress protocol provides a feasible and reliable standardization approach to adjust for water content-related differences induced by age at death, post-mortem interval and tissue processing time with known impact on the stress-strain properties.
尽管已知生物软组织的含水量会改变其力学性能，但在生物力学测试前，几乎没有尝试通过调整组织含水量来作为标准化程序的一部分。本研究的目的是研究含水量变化对宏观和微观组织力学性能的影响。在尸检过程中获取人阔筋膜张肌带样本，通过渗透作用来调节其含水量。使用数字图像相关技术对样本进行宏观机械拉伸测试，并使用原子力显微镜进行微观机械测试。对弹性模量、拉伸强度和最大力下的应变进行了分析，并对水含量、人体测量数据和死后间隔时间进行了相关性分析。在不同的水浓度下存在不同的机械性能。在接近自然状态的水浓度下，更有可能发现与人体测量数据的相关性。这些数据强调了需要调整软组织的含水量，以优化宏观和微观生物力学实验的有效性。渗透压力方案提供了一种可行且可靠的标准化方法，可用于调整因死亡年龄、死后间隔时间和组织处理时间引起的与含水量相关的差异，这些因素已知会对应力-应变特性产生影响。
