Articular cartilage is a thin layer of specialized connective tissue that covers the ends of bones where they come together to form joints. It is a living tissue that is self-lubricating because of its high fluid content, which gives it the lowest coefficient of friction of any natural or man-made material. The chondrocyte is the resident cell type in articular cartilage, which originates from mesenchymal stem cells and constitutes about 2% of the total volume of articular cartilage. Articular cartilage is unique in its ability to withstand high cyclic loads, demonstrating little or no evidence of damage or degenerative change.
Articular cartilage injuries are a common joint injury, especially among those who are physically active. Articular cartilage damage in the knee may be found on its own but it will more often be found in conjunction with injuries to ligaments and menisci. Articular cartilage does not usually regenerate after injury or disease leading to loss of tissue and formation of a defect. Several surgical techniques have been developed in the effort to repair articular cartilage defects.
