Transient stiffening of cartilage during joint articulation: A microindentation study
Transient stiffening of cartilage during joint articulation: A microindentation study
复制标题
关节连接过程中软骨的瞬时硬化：微压痕研究
DOI：
10.1016/j.jmbbm.2020.104113
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发表时间：
2021
影响因子：
3.9
通讯作者：
Wimmer, Markus A.
中科院分区：
文献类型：
--
作者：
Yuh, Catherine;Laurent, Michel P.;Espinosa-Marzal, Rosa M.;Chubinskaya, Susan;Wimmer, Markus A.
关节软骨作为一种机械活动组织，每天都会受到压缩和剪切。随着高分辨率和灵敏的机械测试方法的出现，如微压痕和纳米压痕，评估由于组织的压缩和剪切而引起的小规模机械性能的变化已经成为可能。然而，对关节连接前后这些特性变化的研究还很有限。为了模拟人体步态中软骨的关节负荷，使用了先前开发的生物反应器系统。在生物反应器测试后，立即用微压痕法测量硬度。具体地说，我们调查了组织的机械反应是暂时的还是永久性的，取决于对接材料，以及仅限于软骨表层的影响。我们发现，关节负荷后，软骨表面硬度立即增加，并在3小时内恢复到基线值。软骨对软骨的硬化比氧化铝和钴铬对软骨的硬化都要高，两者之间没有显著差异。这种僵硬反应被发现是表浅区域独有的，因为去除表浅区域的软骨上的关节负荷没有显示僵硬的变化。这项研究的结果表明，软骨表面区可能会适应其僵硬，作为对关节负荷的反应。由于在骨关节病的病程中，浅表区经常受到损害，这一发现具有临床意义，表明承载功能随着时间的推移而恶化。
As a mechanoactive tissue, articular cartilage undergoes compression and shear on a daily basis. With the advent of high resolution and sensitive mechanical testing methods, such as micro- and nanoindentation, it has become possible to assess changes in small-scale mechanical properties due to compression and shear of the tissue. However, investigations on the changes of these properties before and after joint articulation have been limited. To simulate articular loading of cartilage in the context of human gait, a previously developed bioreactor system was used. Immediately after bioreactor testing, the stiffness was measured using microindentation. Specifically, we investigated whether the mechanical response of the tissue was transient or permanent, dependent on counterface material, and an effect limited to the superficial zone of cartilage. We found that cartilage surface stiffness increases immediately after articular loading and returns to baseline values within 3 hr. Cartilage-on-cartilage stiffening was found to be higher compared to both alumina- and cobalt chromium-on-cartilage stiffening, which were not significantly different from each other. This stiffening response was found to be unique to the superficial zone, as articular loading on cartilage with the superficial zone removed showed no changes in stiffness. The findings of this study suggest that the cartilage superficial zone may adapt its stiffness as a response to articular loading. As the superficial zone is often compromised during the course of osteoarthritic disease, this finding is of clinical relevance, suggesting that the load-bearing function deteriorates over time.