occurs when the joints in the body are inflamed or there is a breakdown of cartilage in the joints. Joints are places in the body where two or more bones meet, such as the hip or knee. Cartilage is the cushion in the joints that protects them from pressure and makes movements smooth. When cartilage breaks down in a joint, the bones rub together. This causes pain, swelling and stiffness that often gets worse with aging.
The most common type of arthritis is osteoarthritis. With this type of arthritis, the cartilage in the joints wear out over time from use or as the person ages. Injury to a joint may also lead to this type of arthritis. Osteoarthritis occurs most often in the knees, hips and hands. The joints begin to ache and thicken. At times, the tissues around the joint become strained and cause more pain.
Rheumatoid arthritis is another common type of this kind of arthritis. The immune system, which normally protects the body from infection, attacks the lining of the body’s joints. It causes inflamed and painful joints and may affect other parts of the body, such as the heart, muscles, blood vessels, nerves and eyes.