We have all heard about cartilage, but how much do you understand what it is and what is does for you? Here are 5 key things you should know. The list cound go on and on !
Cartilage is incredibly smooth. Joint cartilage is one of the smoothest known substances. The friction of cartilage against itself, for example between the thigh and leg bone, is about 1000 slicker than ice on ice. It is this amazing property that allows your joints to move smoothly for millions of steps.
- Cartilage is mostly water. The majority of joint cartilage is made of water. The solid part of cartilage acts like a sponge to let water in and out, cushioning with each step as you walk, springing up and down. When a joint becomes inflamed it starts to make too much water, and the joint looks swollen. The fluid is not the problem, it is a sign that the joint is irritated.
- All cartilage is not the same. There are three kinds of cartilage in the body. The cartilage that makes up your ear is similar, but obviously performs a completely different function than that in any of your joints. The cartilage in each joint is different as well, as a finger joint works differently than a knee joint.
- Cartilage grows slowly. The cells in cartilage, called ‘chondrocytes’ are metabolically very slow. They do not have a blood supply like cells in your skin, or heart of brain. They receive oxygen from the joint fluid and are well adapted to this environment. In fact, they trhrive when used when we walk. Cartilage that is not used does not do well in the long run and prefers to be used. The chondrocytes have been shown to function better in a working joint.
- The meniscus is not a cartilage. All the time, I hear patients call the meniscus a cartilage . It is NOT. The meniscus sits between the bones of the knee joint and does a lot of important things. A meniscus tear is not a cartilage tear.

Please let me know if you have questions or ideas to better understand cartilage.
Interesting article. Would like more on joints , arthritis particularly in the foot which I am now suffering from.
Love this article! That you!
I would love to learn more about meniscus,
how it’s formed, grows and work that’s being done not only to heal it but to grow it on a lattice.
Peticularly The medial Meniscus is of interest to me.
Thank you Doctor Hacker and staff!
John Z