Multiscale strain analysis of tendon subjected to shear and compression demonstrates strain attenuation, fiber sliding, and reorganization
Multiscale strain analysis of tendon subjected to shear and compression demonstrates strain attenuation, fiber sliding, and reorganization
复制标题
DOI：
10.1002/jor.22955
复制
发表时间：
2015-11-01
影响因子：
2.8
通讯作者：
Lake, Spencer P.
中科院分区：
文献类型：
--
作者：
Fang, Fei;Lake, Spencer P.
应变沿肌腱的分级长度尺度传递的方式决定了胶原网络内的细胞如何调节组织对负荷的反应。肌腱在剪切和压缩下如何在不同层次上变形是未知的。本研究的目的是：（i）评估牛深趾屈肌腱的特定区域是否表现出不同的应变衰减从宏观到微观的长度尺度，和（ii）阐明机制负责肌腱变形下剪切和压缩。屈肌腱远端和近端区域的样品进行了三步增量应力松弛试验。在加载之前和之后收集组织标记物、胶原纤维上的光漂白线和细胞核位置的图像。结果表明，在剪切和压缩下，应变从组织到局部基质的传递都是衰减的。核纵横比表现出较小的变化为远端样品，这表明细胞更屏蔽变形的远端区域。胶原纤维滑动被观察到有助于显着响应剪切，而卷曲和纤维重组的主要机制下压缩。这项研究提供了洞察微观机制负责多尺度应变衰减的肌腱在非拉伸宏观加载。(c)2015骨科研究学会。由威利期刊公司出版J Orthop Res 33：1704-1712，2015.
The manner in which strains are passed down the hierarchical length scales of tendons dictates how cells within the collagen network regulate the tissue response to loading. How tendons deform in different hierarchical levels under shear and compression is unknown. The aims of this study were: (i) to evaluate whether specific regions of bovine deep digital flexor tendons exhibited different strain attenuation from macro to micro length scales, and (ii) to elucidate mechanisms responsible for tendon deformation under shear and compression. Samples from distal and proximal regions of flexor tendons were subjected to three-step incremental stress-relaxation tests. Images of tissue markers, photobleached lines on collagen fibers, and nuclei locations were collected before and after loading. Results showed that strain transfer was attenuated from tissue to local matrix under both shear and compression. Nuclear aspect ratios exhibited smaller changes for distal samples, suggesting that cells are more shielded from deformation in the distal region. Collagen fiber sliding was observed to contribute significantly in response to shear, while uncrimping and fiber reorganization were the predominant mechanisms under compression. This study provides insight into microscale mechanisms responsible for multiscale strain attenuation of tendons under non-tensile macroscale loading. (c) 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1704-1712, 2015.