Osteoarthritis (OA), which is also known as osteoarthrosis or degenerative joint disease (DJD), is a disorder of the joints that worsens over time. It results from deterioration or loss of the cartilage that acts as a protective cushion between bones, particularly in weight-bearing joints such as the kneesand hips. As the cartilage wears away, the bone forms hardened areas called spurs and fluid-filled pockets in the marrow, known as subchondral cysts. Thedeformed bones and fluid accumulation in the joints cause pain, which is madeworse by moving the joint or putting weight on it. Rest usually relieves thepain.
People with osteoarthritis may have joint pain on one or both sides of the body. It affects mainly the knees, hands, hips, feet, and spine.
Osteoarthritis usually appears after age 40. About 90% of Americans will showsome signs of the disorder in their weight-bearing joints by that 40. In theearly stages of osteoarthritis, the pain is minor and may take the form of mild stiffness in the morning. In later stages, inflammation develops. The patient may have pain even when the joint is not being used and may lose the ability to move the joint normally.
Until the late 1980s, osteoarthritis was thought to be a normal part of aging, caused by simple "wear and tear" on the joints. But recent research into cartilage formation has led to new understanding. Osteoarthritis is now considered to be the end result of several different factors contributing to cartilage damage, and is classified as either primary or secondary.
Primary osteoarthritis is caused by from abnormal stresses on weight-bearingjoints or normal stresses on weak joints. Finger joints, hips, knees, the neck and back and big toe are most frequently affected. People with certain genemutations appear to be more susceptible to primary osteoarthritis. Obesity also contributes to the problem by increasing the pressure on the weight-bearing joints of the body. Age is a factor, too. As the body ages, cartilage loses its ability to repair itself. In addition to these factors, some researchers theorize that primary osteoarthritis may be triggered by enzyme disturbances, bone disease, or liver problems.
Secondary osteoarthritis results from repeated or sudden injury to a joint. It can occur in any joint.Sports injuries, gout, poor posture, metabolic disorders, and repetitive stress injuries associated with certain occupations (like the performing arts, construction or assembly line work, and computer keyboard operation) may lead to secondary osteoarthritis.
Physicians diagnose osteoarthritis using a combination of physical examination and imaging methods such as x rays, magnetic resonance imaging (MRI) and computed tomography scans (CT scans). In the physical examination, the doctor will touch and move the patient's joint, checking for swelling, pain, and cracking or grinding sounds. In patients with osteoarthritis, x rays may show narrowed joint spaces, unusually dense areas in the bone, and the presence of subchondral cysts or bone spurs.
Treatment for osteoarthritis usually involves a combination of medication andphysical therapy. Most patients with are given nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Motrin, Advil), ketoprofen (Orudis), and flurbiprofen (Ansaid), which reduce inflammation as well as relievingpain. However, NSAIDs also may have undesirable side effects including stomach ulcers, sensitivity to sun exposure, kidney problems, and nervousness or depression. Some osteoarthritis patients are treated with corticosteroids injected directly into the joints to reduce inflammation. However, this should bedone no more than two or three times a year.
Exercises that increase balance, flexibility, and range of motion are recommended for osteoarthritis patients. These may include walking, swimming and other water exercises, yoga and other stretching exercises, or isometric exercises. Physical therapy may also include massage, moist hot packs, or soaking ina hot tub.
In severe cases, surgery may be necessary to replace a damaged joint with anartificial one or to remove parts of bone.
Several new treatments are being investigated, including drugs that help thebody repair damaged cartilage; injections of hyaluronic acid, which may helplubricate protect cartilage; and cartilage transplantation.
Some osteoarthritis patients say they get relief from taking supplements of glucosamine or a combination of glucosamine and chondroitin. These substancesare believed to help the body maintain and repair cartilage, and studies conducted in Europe have shown some effectiveness.
While there is no permanent cure for osteoarthritis, many people are able tofind relief and slow the progression of the condition with a combination of weight control, appropriate exercise and medication.