Cartilage Damage
Knee cartilage is the cushion between the ends of the bones that form the knee joint. Damage to articular cartilage is usually associated with aging, but it can also be caused by an injury. Wearing of this cartilage lets the bones rub together, causing pain and stiffness.

Treatment can include medication to reduce inflammation and pain, repair of the damaged cartilage with a specialized treatment for re-generation of tissue, injections into the joint to reduce pain, stiffness, or total/partial knee replacement.