What do your knees, ears and ribs all have in common? Well aside from all being part of you and your body, they contain cartilage.
Cartilage serves many functions, but when it comes to working you need to know that it lines your joints and allows bones to slide over one another. So cartilage reduces friction and prevents damage to the joint. It also acts as a shock absorber helping to decrease the force of impact on bones. Think of it like a cushion. You want to take care of your cartilage because this tough fiber is avascular, meaning it doesn't have blood flow so when it is injured it takes a long time to heal. Not only is it tough but it is also flexible and elastic and is considered a connective tissue, since you find it where bones connect.
Cartilage also forms part of the structure of the skeleton in the ribs, where it joins them to the breastbone (aka the sternum), and it is found in the tip of the nose as well as in the external ear.
Breakdown in the cartilage can lead to osteoarthritis, sometimes called degenerative arthritis. Aging generally causes osteoarthritis, and there can be a hereditary component as well. Other conditions that can lead to osteoarthritis include obesity, injury or surgery to a joint, gout and diabetes. Joints that are commonly affected are in the hands, feet and spine and the major weight bearing joints in the legs - hips and knees.