Types of Arthritis

Osteoarthritis

The most common form of arthritis is osteoarthritis (OA), also known as “wear and tear” or degenerative arthritis. It is estimated that approximately 10% of people in the United States are affected by osteoarthritis, rising to 70% to 90% of people older than 75. OA is caused by the gradual degeneration of joint cartilage, which normally acts to cushion the bones in a joint. Healthy cartilage replaces itself, a process that is disrupted when osteoarthritis sets in. When the cushion of cartilage disappears, the bones can thicken and often produce bone spurs that protrude into the joint, causing inflammation and subsequent pain and stiffness. Osteoarthritis is most commonly found in the knees, hips, hands, and spine.

Lupus

Lupus is an autoimmune disease in which the immune system attacks healthy cells and tissues in various parts of the body, most particularly the joints, skin, blood, and kidneys.

Fibromyalgia

Fibromyalgia is characterized by pain, stiffness, and tenderness in the joints, muscles, and tendons. These symptoms are accompanied by sleep problems, fatigue, and anxiety. Patients suffer generalized aching and pain and have multiple tender points (areas of localized pain when pressure is applied) located in the neck, spine, shoulders, hips, and knees. A diagnosis of FM is made when pain has persisted for longer than three months and the patient has pain in 11 of the 18 specific tender point areas.

Fibromyalgia does not cause the inflammation found in the other types of arthritis discussed above. Because of this, damage to the joints or internal organs of the body and/or joint deformities are not part of this disease.

Researchers have found a higher incidence of sleep apnea and restless leg syndrome in fibromyalgia patients, suggesting that inadequate sleep may be a possible contributor to the condition. Other studies suggest that low levels of the stress hormone cortisol are associated with fibromyalgia.

Fibromyalgia is diagnosed most frequently in women of childbearing age but can also occur among men and younger and older women. The disease is more common among people who have a family history of fibromyalgia or other pain-related disorders.

Juvenile Rheumatoid Arthritis

Juvenile rheumatoid arthritis is an autoimmune disease, as is rheumatoid arthritis among adults. The immune system attacks healthy cells and tissues, resulting in pain, swelling, and heat around the joints. Scientists suspect a genetic tendency toward the disease, triggered by a bacterial or viral infection. JRA onset has been linked to the rubella virus and enteric (intestinal) bacterial infections, among others, but research continues to investigate this relationship.

American Juvenile Arthritis Organization

Gout

Gout accounts for about 5% of all arthritis cases, affecting close to 1 in 30 Americans. It is one of the most painful of all rheumatic diseases. Gout results when deposits of uric acid crystals locate in different parts of the body, most frequently the joints. Uric acid crystals form when there is an excess of uric acid (hyperuricemia) built up in the body. This can result from the body producing too much uric acid or not excreting enough of the acid through the kidneys.

The big toe is the most common site of gout (about 75% of patients), but the ankle, knee, wrist, hand, elbow, and foot can also be affected. The crystal deposits cause inflammation in the joint, resulting in pain and swelling, often with sudden onset. Men are four times more likely to develop gout than women, with onset rare before age 30 and most frequently between 40 and 50. Women are more likely to develop gout after the age of 60.

Rheumatoid Arthritis

Rheumatoid arthritis (RA), the most common connective tissue disorder, is a chronic autoimmune disorder. It occurs in approximately 1% to 2% of the population and is two to three times more likely to be diagnosed in women than in men, often developing in women between the ages of 30 and 50. Among the elderly, men and women are equally likely to develop RA.