Called the “wear and tear” arthritis, Osteoarthritis (OA) is the most common form of arthritis. Nearly all vertebrates suffer from OA, including porpoises and whales, and those long-extinct giants, the dinosaurs. It is a chronic disease in which the cartilage breaks down. Cartilage is a slippery tissue that covers the ends of bones in a joint, allowing the bones to glide over one another. It also absorbs energy from the shock of physical movement. When cartilage in a joint deteriorates, OA occurs.
Statistics
- OA affects an estimated 20.7 million Americans.
- It is 8 times more common than Rheumatoid arthritis.
- Almost everyone over the age of 75 is affected in at least one joint.
- Before age 45, more men have it, while after age 45 it is more common in women.
- OA is responsible for more than 7 million physician visits per year.
What causes it?
There are two categories of OA, primary and secondary. Primary OA appears without any apparent cause, usually as a result of aging. Secondary OA occurs in joints that have sustained injuries, experienced infections or fractures. The pain of OA is often caused by ligament relaxation around the joint. Obesity can also cause secondary OA due to the added pressure on weight bearing joints. Secondary OA can also occur as the result of another type of arthritis, such as rheumatoid.
In cases of OA, old cartilage breakdown exceeds new cartilage synthesis and may be associated with loose ligaments. Maintaining the integrity of the synovial joints is fundamental to osteoarthritis prevention.
What are the symptoms?
As the cartilage in a joint deteriorates the bones begin to rub together, causing pain, swelling, and loss of motion of the joint. The joint may begin to lose shape. Small bone spurs called osteophytes may grow on the edges of the joint. Inflammation may or may not be present. The pain may act like a roller coaster, with pain spells followed by periods of relief. These symptoms almost always begin gradually, taking years until the pain is severe enough to be reported to a doctor. OA is commonly found in the joints of the fingers, feet, knees, hips, and spine, and is rarely found in joints of the wrist, elbows, shoulders or jaw.
How is it diagnosed?
Although it is usually not difficult to diagnose OA, no single test can pinpoint the disease. Most doctors use a combination of patient history and exam, and X-rays to diagnose the disease and rule out other causes for the symptoms.
How is it treated?
Treatment of OA should focus on managing pain while improving joint function by strengthening the joint and encouraging cartilage growth. This can be done in several ways.
People in occupations or activities requiring repetitive and stressful movement should find ways to reduce joint trauma. Adjusting the work area, substituting tasks or changing exercise activities to produce less stress on joints can help reduce further ‘wear and tear’.
Treatment plans recommended by some doctors include regularly scheduled rest. Others, however, stress the importance of continued mobility during the recovery phase, if tolerated. Corticosteroids are typically injected into affected joints rather than taken orally to relieve the pain, but repeated injections may further weaken loose ligaments and prevent healing which requires an inflammatory like response.