Tsujii Akira, Nakamura Norimasa, Horibe Shuji
Department of Orthopedics, Yao Municipal Hospital, Yao, Osaka, Japan.
Institute for Medical Science in Sports, Osaka Health Science University, Osaka, Japan.
Knee. 2017 Dec;24(6):1262-1270. doi: 10.1016/j.knee.2017.08.001. Epub 2017 Sep 30.
Aging is the most prominent risk factor for the development of osteoarthritis (OA), which affects knees and causes major health burdens. Meniscal dysfunction mostly based on degeneration contributes to the development and progression of knee OA. Meniscal degeneration is caused by various extrinsic factors, such as repetitive trauma or leg malalignment, while meniscal aging is considered as internal changes, such as molecular or cellular changes. Little is known about age-related changes in the meniscus. Therefore, this review aimed to summarize and clarify the understanding of the aged meniscus.
There are few articles about natural aging in the meniscus, because most reports only demonstrate the effects of OA on the meniscus. We searched PubMed (1948 to November 2016) to identify and summarize all English-language articles evaluating natural aging in the meniscus.
There is evidence of compositional change in the meniscus with aging, involving cells, collagens, and proteoglycans. In addition, as recent reports on the natural aging of cartilage have indicated, senescence of the meniscal cells may also lead to disruption of meniscal cells and tissue homeostasis. Due to the low turnover rate of collagen, accumulation of advanced glycation end-products largely contributes to tissue stiffness and vulnerability, and finally results in degenerative changes or tears. Furthermore, environmental factors such as joint fluid secreted by inflamed synovium could also contribute to meniscal tissue deterioration.
Age-related changes induce meniscal tissue vulnerability and finally lead to meniscal dysfunction.
衰老是骨关节炎（OA）发生的最主要风险因素，OA影响膝关节并造成重大健康负担。主要基于退变的半月板功能障碍会促使膝关节OA的发生和发展。半月板退变由多种外在因素引起，如重复性创伤或腿部力线不正，而半月板老化则被视为内部变化，如分子或细胞层面的变化。目前对半月板随年龄增长的变化了解甚少。因此，本综述旨在总结并阐明对老化半月板的认识。
关于半月板自然老化的文章很少，因为大多数报告仅阐述了OA对半月板的影响。我们检索了PubMed（1948年至2016年11月），以识别并总结所有评估半月板自然老化的英文文章。
有证据表明半月板会随着年龄增长发生成分变化，涉及细胞、胶原蛋白和蛋白聚糖。此外，正如最近关于软骨自然老化的报告所示，半月板细胞的衰老也可能导致半月板细胞和组织内环境稳态的破坏。由于胶原蛋白的更新率较低，晚期糖基化终产物的积累在很大程度上导致了组织僵硬和易损性，最终导致退行性改变或撕裂。此外，诸如炎症滑膜分泌的关节液等环境因素也可能导致半月板组织退变。
与年龄相关的变化会导致半月板组织易损性增加，最终导致半月板功能障碍。
