Study on the pathogenesis of osteoarthrosis secondary to scraping the surface of the articular cartilage : with special interest on the importance of the surface layr of the articular cartilage

关节软骨的表层没有胶原纤维和细胞，有助于关节的润滑，并保护软骨免受外源性酶的消化。LayR主要由蛋白多糖组成，蛋白多糖是软骨的主要成分。在兔膝关节的关节表面刮除关节软骨表层时，关节常发生骨关节病。骨关节病的发展依赖于刮除的区域。刮除面积大时，骨关节病的发生率高。本研究旨在阐明骨关节病的发病机制，特别是骨关节病的发生发展与关节软骨表面层的关系。对两组兔进行了检查。在一组患者中，右膝只有三分之一的股骨关节表面被刮伤。在另一个，几乎整个关节S…股骨髁表面有较多擦伤。在前一组中，动物的右膝没有发生骨关节病，而在后一组中的兔经常发生骨关节病。低温扫描电子显微镜下，小刮伤区在1周内即可见表层再生。当时，因擦伤而受损的关节的润滑剂已恢复到正常水平。免疫组织化学检测显示，刮伤区再生的表面层由蛋白多糖组成，与正常软骨的表面层一样。透射电子显微镜显示细胞内器官丰富，表明擦伤区域及其周围的软骨细胞增加了细胞外基质的产生。在几乎整个膝关节表面都被擦伤的组中，动物经常发生膝关节骨关节病。刮削区未见表面层。关节的润滑性受损没有得到改善，退行性改变继续进行。这些结果表明，关节表面刮除后骨关节病的发展与表面层的恢复有关，而表面层的恢复依赖于刮除的区域。当刮除面积较小时，表面层由激活的软骨细胞分泌再生，不会发生进行性骨关节改变。当刮除面积较大时，表面层无法被细胞修复，关节软骨发生进行性变性破坏。较少

The surface layr of the articular cartilage, which is devoid of collagen fibrils and cells, contributes to the lubrication of the joint and protects the cartilage from digestion by exogenous enzymes. The layr is mainly composed of proteoglycan, a major constituent of the cartilage. When the surface layyr was removed from the articular cartilage by scraping the articular surface of the rabbit knee, osteoarthrosis frequently developed in the joint. The development of osteoarthrosis was dependent on the scraped area. When the scraped area was large, the incidence of the development of osteoarthrosis was high. The purpose of the present study was to elucidate the pathogenesis of osteoarthrosis, especially the relationship between the development of osteoarthrosis and the surface layr of the articular cartilage. Two groups of rabbits were examined. In one group, only central one-third of the femoral articular surface was scraped in the right knee. In the other, almost the entire articular s … More urface of the femoral condyles was scraped. In the former group, animals did not develop osteoarthrosis in their right knees, while rabbits in the latter group frequently developed osteoarthrosis. In the cryo-scanning electron microscopy, in the group of the small scraped area, the surface layr was regenerated in the scraped area with in a week. At that point of time, lubrication of the joint, which had been impaired by the scraping, was restored to the normal level. Immuno-chemical examination revealed that the regenerated surface layr in the scraped area was composed of proteoglycan as the layr in the normal cartilage. Transmission electron microscopy showed enrichment of intracellular organs, indicating enhanced production of extracellular matrix by the chondrocytes in and around the scraped area. In the group in which almost entire articular surface of the knee joint was scraped, animals frequently developed osteoarthrosis of the knee joint. In the scraped area, the surface layr was not observed. The impaired lubrication of the joint was not improved, and the degenerative changes progressed. These results indicated that the development of osteoarthrosis after scraping the articular surface was related to the restoration of the surface layr which was dependent on the scraped area. When the scraped area was small, the surface layr is regenerated by activated secretion of chondrocytes and progressive osteoarthrotic changes do not occur. When the scraped area was large, the surface layr was not restored by the cells and the articular cartilage undergo progressive degeneration and destruction. Less