Osteoarthritis, commonly known as wear-and-tear arthritis, is a condition in which the natural cushioning between joints -- cartilage -- wears away.
When this happens, the bones of the joints rub more closely against one another with less of the shock-absorbing benefits of cartilage.
The rubbing results in pain, swelling, stiffness, decreased ability to move and, sometimes, the formation of bone spurs.
Knee osteoarthritis is very common, especially as people age. It happens when the cartilage that cushions the knee joint starts to wear down.
That can happen as you get older or because of an old injury or other stresses on the joints. The chance of developing osteoarthritis rises after age 45. Women are more likely to have osteoarthritis than men.
Keywords: knee joint osteoarthritis; knee osteoarthritis.