ARTHRITIS: OVERVIEW

Arthritis is the inflammation of a joint, which causes localized pain, swelling and stiffness. There are several different types of arthritis. The most common type is osteoarthritis, or degenerative arthritis, which involves changes in the joint cartilage as a result of aging and use. As the cartilage deteriorates, the bones of the joint thicken and become distorted. The affected joint may become swollen. Because movement of the joint is restricted and painful, the associated muscles begin to shrink from lack of use.

Osteoarthritis generally affects the large, weight-bearing joints, such as the spine, hips, and knees, but the finger joints may also be affected. The pain and discomfort of osteoarthritis may be lessened with aspirin, ibuprofen or other nonsteroidal anti-inflammatory drugs (NSAIDs). When pain is intolerable, injections of corticosteroid drugs into the affected joint may be given on a limited basis. Physical therapy, such as exercise, massage and heat treatments, also may be prescribed.

When joints are severely damaged by osteoarthritis, producing chronic pain and preventing normal movement of limbs, they may be surgically replaced with artificial joints made of metal or metal combined with plastic or porcelain. Hip and knee joints are often successfully replaced. Self-help treatments for osteoarthritis include losing weight, using a cane to relieve pressure on a joint, applying heat to ease pain, and exercising regularly to strengthen muscles surrounding the affected joints. Although many joints may be affected by osteoarthritis, the inflammation does not involve other organ systems.

Other types of arthritis include gouty arthritis, which is caused by urate crystals forming in the joints, and a temporary form of arthritis that may accompany acute rheumatic fever. Infectious diseases, including hepatitis B and C and rubella (or German measles), can cause temporary arthritis, which is an uncommon side effect of the rubella vaccination. In these cases, as in the case of temporary arthritis with acute rheumatic fever, the joints are not permanently damaged or deformed.

Rheumatoid arthritis, an autoimmune disease, is a more serious, systemic form of arthritis, which may affect the heart, lungs and eyes, as well as the joints. The suspected cause is an unidentified virus that stimulates the immune system. Disease-fighting cells that are subsequently released by the immune system inflame the joints.