Wong M, Ponticiello M, Kovanen V, Jurvelin J S
M.E. Mueller Institute for Biomechanics, University of Bern, Switzerland.
J Biomech. 2000 Sep;33(9):1049-54. doi: 10.1016/s0021-9290(00)00084-1.
The time-dependent lateral expansion and load relaxation of cartilage cylinders subjected to unconfined compression were simultaneously recorded. These measurements were used to (1) test the assumption of incompressibility for articular cartilage, (2) measure the Poisson's ratio of articular cartilage in compression and (3) investigate the relationship between stress relaxation and volumetric change. Mechanical tests were performed on fetal, calf, and adult humeral head articular cartilage. The instantaneous Poisson's ratio of adult cartilage was 0.49+/-0.08 (mean+S.D.), thus confirming the assumption of incompressibility for this tissue. The instantaneous Poisson's ratio was significantly lower for calf (0. 38+/-0.04) and fetal cartilage (0.36+/-0.04). The equilibrium Poisson's ratio, i.e. true Poisson's ratio of the solid matrix, was significantly higher for the adult tissue (0.26+/-0.11) compared to both the fetal (0.09+/-0.02) and calf (0.11+/-0.03) cartilage. A linear relationship between time-matched load and lateral expansion after the first minute of stress relaxation was observed.
记录了承受无侧限压缩的软骨圆柱体随时间的横向扩张和载荷松弛情况。这些测量用于：（1）检验关节软骨不可压缩性的假设；（2）测量压缩状态下关节软骨的泊松比；（3）研究应力松弛与体积变化之间的关系。对胎儿、小牛和成人的肱骨头关节软骨进行了力学测试。成人软骨的瞬时泊松比为0.49±0.08（平均值±标准差），从而证实了该组织不可压缩性的假设。小牛软骨（0.38±0.04）和胎儿软骨（0.36±0.04）的瞬时泊松比明显更低。与胎儿软骨（0.09±0.02）和小牛软骨（0.11±0.03）相比，成人组织的平衡泊松比，即固体基质的真实泊松比，明显更高（0.26±0.11）。在应力松弛第一分钟后，观察到时间匹配的载荷与横向扩张之间存在线性关系。
