Osteoarthritis

Alternative names:

degenerative joint disease; DJD; hypertrophic osteoarthritis; osteoarthrosis

Definition:

A chronic disease causing deterioration of the joint cartilage and other joint tissues with the formation of new bone (bone spurs) at the margins of the joints.

Causes, incidence, and risk factors:

The cause of osteoarthritis is unknown, but metabolic, genetic, chemical, and mechanical factors may play a role in development. It is associated with the aging process and is the most common form of arthritis. It may first appear without symptoms between 20 and 30 years of age and is present in almost everyone by the age of 70. Symptoms appear in middle age. Before the age of 55 it occurs equally in both sexes; however, after 55 the incidence is higher in women. Approximately 4 out of 100 people are affected.

The cartilage of the affected joint is roughened and becomes worn down. As the disease progresses, so much of the cartilage is worn down that the bone ends start to rub against each other. Bony spurs may develop around the joint, causing pain and inflammation.

Systemic symptoms, sometimes associated with other arthritic conditions, are not associated with osteoarthritis. The joints of the hands and fingers, hips, knees, big toe, cervical and lumbar spine are commonly affected. The degeneration of the joint may occur as a result of injury or trauma to the joint, rheumatoid arthritis, occupational overuse, obesity, or metabolic diseases.