Regional variations in discrete collagen fibre mechanics within intact intervertebral disc resolved using synchrotron computed tomography and digital volume correlation.
Regional variations in discrete collagen fibre mechanics within intact intervertebral disc resolved using synchrotron computed tomography and digital volume correlation.
复制标题
DOI：
10.1016/j.actbio.2021.10.012
复制
发表时间：
2022-01-15
影响因子：
9.7
通讯作者：
Bay BK
中科院分区：
文献类型：
--
作者：
Disney CM;Mo J;Eckersley A;Bodey AJ;Hoyland JA;Sherratt MJ;Pitsillides AA;Lee PD;Bay BK
许多软组织，如间盘(IVD)，具有层次化的纤维复合结构，受到局部损害。我们假设这些组织区域具有独特的、固有的纤维结构和加载时的结构反应。在这里，我们使用同步加速器计算机断层扫描(SCT)在增加压缩负荷的情况下，在完整的自然大鼠腰椎IVD中以3D方式解析胶原纤维束(∼5μm宽)。使用完整的样本意味着组织边界(如终板-盘或核-环)和残余应变被保留；这对于表征固有结构和在近自然环境中发挥作用的组织区域的结构变化是至关重要的。我们跟踪了10,000根单独的纤维的纳米尺度位移测量，并比较了后外侧区域和前侧区域之间的纤维取向、曲率和应变变化。这些方法可以广泛应用于其他软组织，以识别导致组织区域更容易损伤和退化的纤维结构。我们的结果首次表明，纤维取向、曲率和应变的高度局部化变化表明局部应变转移和机械功能(例如组织顺应性)的差异。这包括在较高载荷下纤维重定向减少，特殊的组织形态降低了弹性能力，以及在椎间盘-终板边界处的高应变。本文的分析方法适用于许多局部受损的胶原软组织。我们的目的是通过表征胶原纤维的结构并将特定的纤维和组织水平的变形行为联系起来，来研究区域性椎间盘(IVD)结构和功能的差异。同步加速器CT提供了第一个在完整的IVD内追踪3D离散纤维的演示。使用超过200k个点，沿着10k个单独的纤维每隔8μm对区域进行详细分析。这种全面的结构特征对于未来的计算模型具有重要意义。组织顺应性的形态指标(纤维曲率和取向的变化)和纤维应变测量揭示了组织行为的局部和区域差异。
Many soft tissues, such as the intervertebral disc (IVD), have a hierarchical fibrous composite structure which suffers from regional damage. We hypothesise that these tissue regions have distinct, inherent fibre structure and structural response upon loading. Here we used synchrotron computed tomography (sCT) to resolve collagen fibre bundles (∼5μm width) in 3D throughout an intact native rat lumbar IVD under increasing compressive load. Using intact samples meant that tissue boundaries (such as endplate-disc or nucleus-annulus) and residual strain were preserved; this is vital for characterising both the inherent structure and structural changes upon loading in tissue regions functioning in a near-native environment. Nano-scale displacement measurements along >10,000 individual fibres were tracked, and fibre orientation, curvature and strain changes were compared between the posterior-lateral region and the anterior region. These methods can be widely applied to other soft tissues, to identify fibre structures which cause tissue regions to be more susceptible to injury and degeneration. Our results demonstrate for the first time that highly-localised changes in fibre orientation, curvature and strain indicate differences in regional strain transfer and mechanical function (e.g. tissue compliance). This included decreased fibre reorientation at higher loads, specific tissue morphology which reduced capacity for flexibility and high strain at the disc-endplate boundary. The analyses presented here are applicable to many collagenous soft tissues which suffer from regional damage. We aimed to investigate regional intervertebral disc (IVD) structural and functional differences by characterising collagen fibre architecture and linking specific fibre- and tissue-level deformation behaviours. Synchrotron CT provided the first demonstration of tracking discrete fibres in 3D within an intact IVD. Detailed analysis of regions was performed using over 200k points, spaced every 8 μm along 10k individual fibres. Such comprehensive structural characterisation is significant in informing future computational models. Morphological indicators of tissue compliance (change in fibre curvature and orientation) and fibre strain measurements revealed localised and regional differences in tissue behaviour.
登录
查看更多内容
影响因子：
3
作者：
MARCHAND, F;AHMED, AM
通讯作者：
AHMED, AM
影响因子：
2.4
作者：
Michalek, A. J.;Gardner-Morse, M. G.;Iatridis, J. C.
通讯作者：
Iatridis, J. C.
影响因子：
13.6
作者：
Badon A;Li D;Lerosey G;Boccara AC;Fink M;Aubry A
通讯作者：
Aubry A
影响因子：
3
作者：
Berger-Roscher, Nikolaus;Casaroli, Gloria;Wilke, Hans-Joachim
通讯作者：
Wilke, Hans-Joachim
影响因子：
2.9
作者：
CASSIDY, JJ;HILTNER, A;BAER, E
通讯作者：
BAER, E