中文摘要：

背景：研究关节软骨的回弹性能对人的作息以及和人工软骨回弹性能的匹配度等都具有很大的参考意义。目的：分析不同载荷和不同时间下关节软骨回弹的微观力学性能。方法：运用MTF-100拉力机对涂有示踪剂的猪软骨试件进行压缩,用其附带的CCD对软骨压缩和回弹状态进行拍照记录,采用数字图像相关技术进行图像处理。结果与结论：（1）回弹时软骨浅表层回弹的应变减少幅度最大,中间层次之,深层最小,分别从20%、10%、6%左右降到3%所用的时间相似;（2）回弹时间越长,软骨不同层区的应变变化越缓慢,但最终应变会小于1%;（3）相同层区不同压缩载荷作用下,在回弹初期,载荷越大,软骨回弹应变变化越快;在回弹后期,载荷越小,回弹应变变化越快;（4）相同层区不同持续压缩时间和载荷的影响相似;（5）从实验数据看,关节软骨90%左右的回弹主要集中在前15 min左右。关节软骨不同层区的力学回弹性能与其加载载荷和加载持续时间都有密切的相关性,载荷和压缩时间的增加都会对回弹产生不利的影响。从回弹后期数据说明经过一定的时间基本能回弹到压缩前的状态。

英文摘要：

BACKGROUND： It is of great significance to study the resilience of articular cartilage for human daily routine and their match quality. OBJECTIVE： To analyze the micromechanical properties of articular cartilage resilience under different loads and at time points. METHODS： The swine cartilage samples coated with tracers were compressed using the MTF-100 tensile machine, and the cartilage compression and resilience were recorded by CCD. Images were processed using digital image correlation technology. RESULTS AND CONCLUSION： During resilience, the strain value on the superficial surface of the cartilage was decreased most, successively followed by the middle layer and the deep layer, while the time of a decrease from 20%, 10% and 6% to 3% was similar. The longer the resilience time was, the more slowly the strain changed in different layers of the cartilage, but the ultimate strain was less than 1%. On the same layer under different compressive stress, the larger load caused faster strain change firstly, and then the smaller load brought about faster strain change. The effect of different continuous compressive time on the same layer of cartilage was similar with the load. These results showed that 90% resilience of the articular cartilage occurred within the first 15 minutes. The mechanical resilience of different layers of the articular cartilage has a close relationship with the loading and the loading time, and both compressive time and loading do harm to the resilience of articular cartilage. Besides, the cartilage will rebound to the state before compression.