Experimental verification of the role of interstitial fluid pressurization in cartilage lubrication
Experimental verification of the role of interstitial fluid pressurization in cartilage lubrication
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DOI：
10.1016/j.orthres.2003.07.002
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发表时间：
2004-05-01
影响因子：
2.8
通讯作者：
Ateshian, GA
中科院分区：
文献类型：
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作者：
Krishnan, R;Kopacz, M;Ateshian, GA
本研究的目的是测量摩擦系数的同时，在牛关节软骨间质液负载支持，而在恒定负载下对玻璃滑动。从四个牛肩关节（2-4月龄）的肱骨头采集的十个视觉正常的6 mm直径软骨栓在往复线性运动（平移范围+/-2 mm;滑动速度1 mm/s）下在定制摩擦装置中进行测试，承受4.5 N恒定载荷。发现摩擦系数随时间增加，在920 - 19，870 s（中位数：4，560 s）的持续时间内，从最小值mu（min）= 0.010 +/- 0.007（平均值+/- SD）增加到最大值0.243 +/- 0.044。相应的间质液负荷支持从最大值88.8 +/- 3.8%降至8.7 +/-8.6%。在摩擦系数和间质液负荷支持之间观察到线性相关性（r（2）= 0.96 +/- 0.03）。这些结果支持了以下假设：摩擦系数的时间变化与间质液负荷支持呈负相关，因此间质液负荷支持是调节关节软骨摩擦反应的主要机制。拟合的实验数据，以前提出的两相边界润滑模型软骨产生的平衡摩擦系数μ（eq）= 0.284 +/- 0.044。固体软骨基质与载玻片接触的表观接触面积的分数预测为0 = 1.7 +/-6.3%，显著小于组织的固体体积分数phi（s）= 13.8 +/-11.8%。该模型的预测表明，混合润滑盛行在本研究中采用的负载条件下的接触界面。(C)2003骨科研究学会。由爱思唯尔有限公司出版。保留所有权利。
The objective of the current study was to measure the friction coefficient simultaneously with the interstitial fluid load support in bovine articular cartilage, while sliding against glass under a constant load. Ten visually normal 6-mm-diameter cartilage plugs harvested from the humeral head of four bovine shoulder joints (ages 2-4 months) were tested in a custom friction device under reciprocating linear motion (range of translation +/-2 mm; sliding velocity 1 mm/s), subjected to a 4.5 N constant load. The frictional coefficient was found to increase with time from a minimum value of mu(min) = 0.010 +/- 0.007 (mean +/- SD) to a maximum value of 0.243 +/- 0.044 over a duration ranging from 920 to 19,870 s (median: 4,560 s). The corresponding interstitial fluid load support decreased from a maximum of 88.8 +/- 3.8% to 8.7 +/- 8.6%. A linear correlation was observed between the frictional coefficient and interstitial fluid load support (r(2) = 0.96 +/- 0.03). These results support the hypothesis that the temporal variation of the frictional coefficient correlates negatively with the interstitial fluid load support and that consequently interstitial fluid load support is a primary mechanism regulating the frictional response in articular cartilage. Fitting the experimental data to a previously proposed biphasic boundary lubrication model for cartilage yielded an equilibrium friction coefficient of mu(eq) = 0.284 +/- 0.044. The fraction of the apparent contact area, over which the solid cartilage matrix was in contact with the glass slide was predicted at 0 = 1.7 +/- 6.3%, significantly smaller than the solid volume fraction of the tissue, phi(s) = 13.8 +/- 11.8%. The model predictions suggest that mixed lubrication prevailed at the contact interface under the loading conditions employed in this study. (C) 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.