The aim of this article is to provide some insights on the osmo-inelastic response under stretching of annulus fibrosus of the intervertebral disc. Circumferentially oriented specimens of square cross section, extracted from different regions of bovine cervical discs (ventral-lateral and dorsal-lateral), are tested under different strain-rates and saline concentrations within normal range of strains. An accurate optical strain measuring technique, based upon digital image correlation, is used in order to determine the full-field displacements in the lamellae and fibers planes of the layered soft tissue. Annulus stress–stretch relationships are measured along with full-field transversal strains in the two planes. The mechanical response is found hysteretic, rate-dependent and osmolarity-dependent with a Poisson’s ratio higher than 0.5 in the fibers plane and negative (auxeticity) in the lamellae plane. While the stiffness presents a regional-dependency due to variations in collagen fibers content/orientation, the strain-rate sensitivity of the response is found independent on the region. A significant osmotic effect is found on both the auxetic response in the lamellae plane and the stiffness rate-sensitivity. These local experimental observations will result in more accurate chemo-mechanical modeling of the disc annulus and a clearer multi-scale understanding of the disc intervertebral function.

本文的目的是对椎间盘纤维环拉伸下的渗透非弹性反应提供一些见解。从牛颈椎间盘的不同区域（腹外侧和背外侧）提取的方形横截面的圆周取向标本在正常应变范围内的不同应变率和盐水浓度下进行测试。使用基于数字图像相关性的精确光学应变测量技术来确定分层软组织的薄片和纤维平面中的全场位移。测量环面应力-拉伸关系以及两个平面中的全场横向应变。发现机械响应滞后、速率依赖和渗透压依赖，泊松比高于 0。在纤维平面中为 5，在薄片平面中为负（拉胀）。虽然由于胶原纤维含量/方向的变化，刚度呈现出区域依赖性，但发现响应的应变率敏感性与该区域无关。在薄片平面的拉胀反应和刚度速率敏感性上都发现了显着的渗透效应。这些局部实验观察将导致更准确的椎间盘环化学机械建模和对椎间盘椎间功能的更清晰的多尺度理解。在薄片平面的拉胀反应和刚度速率敏感性上都发现了显着的渗透效应。这些局部实验观察将导致更准确的椎间盘环化学机械建模和对椎间盘椎间功能的更清晰的多尺度理解。在薄片平面的拉胀反应和刚度速率敏感性上都发现了显着的渗透效应。这些局部实验观察将导致更准确的椎间盘环化学机械建模和对椎间盘椎间功能的更清晰的多尺度理解。