Approximately 40 million people in the United States have arthritis. It is a disorder of the joints that connect the bones of the body. The name arthritis means joint inflammation or swelling.

Joints are located wherever two or more bones meet. Cartilage and a lubricating fluid form a smooth gliding surface for the bones of the joint. Ligaments hold the joint together. When joints become injured or diseased, they swell. Over 100 types of arthritis affect the joints and connective tissues of the body.

Inflammation is a normal part of the body's defense system. It is a natural reaction to injury. Inflammation causes swelling, pain, and redness. It also decreases motion in the affected area. With arthritis, inflammation becomes part of the problem. It causes tissue damage which the body tries to handle by creating more inflammation. This painful cycle of destruction changes the bones and other joint tissues and limits their function.

The cause of arthritis is unknown, although clues are being uncovered. For example, people with certain gene types are prone to certain forms of arthritis. There also seem to be microorganisms that trigger the onset of arthritis.

Each type of arthritis has different symptoms and patterns and each requires different treatments. The most common forms of arthritis are osteoarthritis and rheumatoid arthritis, followed by spinal arthritis, lupus, gout, scleroderma, and juvenile arthritis.

Some forms of arthritis go through cycles of getting better and worse. A flare-up means the disease is more active. During this time, there is increased morning stiffness, more pain and swelling in the joints, involvement of new joints, and increased tiredness and fatigue. Flare-ups can occur after eating a specific food. Milk is the most common offender. Other foods are shrimp, wheat products, and certain meats.

Treatment for most forms of arthritis includes drugs, exercise, and rest. Joint protection and surgery are sometimes needed as well.

To learn more about arthritis, call the Arthritis Foundation at (800) 283-7800.

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