Articular Cartilage Tidemark in the Murine Knee Advances with Mechanical Loading

Osteoarthritis (OA) is characterized by not only articular cartilage degeneration, but also subchondral bone sclerosis. While mechanically-induced cartilage degeneration may instigate tidemark advancement and subchondral bone thickening, the association between the two structures and the time course of tidemark advancement are unknown. Thus, in this study, we investigated the effects of mechanical loading on mouse tibial articular cartilage. Daily cyclic mechanical loading stimulated tidemark advancement after 6 weeks, with little to no effects after 1 and 2 weeks. Understanding the role of the tidemark in the joint will add to the current knowledge of the mechanisms behind subchondral bone thickening, potentially contributing to a future OA treatment.