Osteoarthritis is a chronic disorder associated with damage to the cartilage and surrounding tissues and characterized by pain, stiffness, and loss of function.
- Arthritis due to damage of joint cartilage and surrounding tissues becomes very common with aging.
- Pain, swelling, and bony overgrowth are common, as well as stiffness that follows awakening or inactivity and disappears within 30 minutes, particularly if the joint is moved.
- The diagnosis is based on symptoms and x-rays.
- Treatment includes exercises and other physical measures, drugs that reduce pain and improve function, and, for very severe changes, joint replacement or other surgery.
Osteoarthritis, the most common joint disorder, often begins in the 40s and 50s and affects almost all people to some degree by age 80. Before the age of 40, men develop osteoarthritis more often than do women, often because of injury. Many people have some evidence of osteoarthritis on x-rays (often by age 40), but only half of these people have symptoms. From age 40 to 70, women develop the disorder more often than do men. After age 70, the disorder develops in both sexes equally.
Osteoarthritis is classified as:
- Primary
- Secondary
In primary (or idiopathic) osteoarthritis, the cause is not known (as in the large majority of cases).
Primary osteoarthritis may affect only certain joints, such as the knee, or many joints.
In secondary osteoarthritis, the cause is another disease or condition, such as
- An infection
- A joint abnormality that appeared at birth
- An injury
- A metabolic disorder—for example, excess iron in the body (hemochromatosis) or excesscopper in the liver
- A disorder that has damaged joint cartilage—for example, rheumatoid arthritis or gout
Some people who repetitively stress one joint or a group of joints, such as foundry workers, farmers, coal miners, and bus drivers, are particularly at risk. The major risk factor for osteoarthritis of the knee comes from having an occupation that involves bending the joint. Curiously, long-distance running does not increase the risk of developing the disorder. However, once osteoarthritis develops, this type of exercise often makes the disorder worse. Obesity may be a major factor in the development of osteoarthritis, particularly of the knee and especially in women
What Can Cause Chronic Pain?Treatment of Osteoarthritis
- Physical measures, including physical and occupational therapy
- Drugs
- Surgery
Chronic Pain Does More Than Just Hurt
Chronic pain can have many, sometimes serious consequences:
- Loss of sleep
- Fatigue and loss of energy
- Loss of appetite
- Lack of participation in activities, resulting in social isolation
- Avoidance of physical activity, resulting in loss of muscle strength and flexibility
- Depression
- For older people, difficulty doing their daily activities and increased dependence on other people
Treatment includes
- Pain relievers such as acetaminophen, aspirin, and other nonsteroidal anti-inflammatory drugs (NSAIDs)
- Other drugs such as certain antidepressants and anticonvulsants
- Other treatments such as biofeedback, relaxation training, distraction techniques, and hypnosis
- Topical Compounds combining multiple pain relievers, muscle relaxers, neuropathic, and analgesics to create multimodal analgesia Doctors may
prescribe opioid pain relievers when other treatments do not work.
The main goals of osteoarthritis treatment are to
- Relieve pain
- Maintain joint flexibility
- Optimize joint and overall function
These goals are primarily achieved by physical measures that involve exercises for strength, flexibility, and endurance and rehabilitation (physical and occupational therapy). People are taught how modifying their daily activities can help them live with osteoarthritis. Additional treatment includes drugs, surgery (for some people), and newer therapies. Drugs are used to supplement exercise and physical therapy. Drugs, which may be used in combination or individually, do not directly alter the course of osteoarthritis. They are used to reduce symptoms and thus allow more normal daily activities. A simple pain reliever (analgesic), such as acetaminophen, used before activities that cause discomfort or used regularly to relieve more constant joint discomfort, may be all that is needed for mild to moderate pain. Although side effects are not common, people should not
take acetaminophen in higher than recommended doses, particularly if they have liver disease. When taking acetaminophen, people should also make sure not to simultaneously take one of the numerous over-the-counter drug products that contain acetaminophen.
Sometimes, however, people may need a more potent analgesic, such as tramadol or rarely opioids. Alternatively, a nonsteroidal anti-inflammatory drug (NSAID) may be taken to lessen pain and swelling. NSAIDs reduce pain and inflammation in joints and can be used in combination with other analgesics. NSAIDs also come in gel and cream forms that can be rubbed into the skin (such as diclofenac gel 1%) over the joints of the hands and knees and may help relieve symptoms. However, NSAIDs have a higher risk of serious side effects than acetaminophen when used long term.
Sometimes other types of pain medicine may be needed. For example, a cream made from cayenne pepper—the active ingredient is capsaicin—can be applied directly to the skin over the joint. Doctors may also recommend lidocaine patches for pain relief, but there is no evidence these patches are effective. Duloxetine, a type of antidepressant taken by mouth, reduces the pain caused by osteoarthritis.
Muscle relaxants (usually in low doses) occasionally relieve pain caused by muscles straining to support joints affected by osteoarthritis. In older people, however, they tend to cause more side effects than relief.
Combinations of multiple drugs from different drug classes can be utilized with topical paincompounds that feature antinflammatory drugs and analgesics. If a joint suddenly becomes inflamed, swollen, and painful, most of the fluid inside the joint may need to be removed and a special form of cortisone may be injected directly into the joint. This treatment may provide temporary pain relief and increased joint flexibility in some people.
A series of 1 to 5 weekly injections of hyaluronate (a substance similar to normal joint fluid) into the knee joint may provide some pain relief in some people for prolonged periods of time. These injections should not be given more often than every 6 months. Hyaluronate injections are less effective in people with severe osteoarthritis.
Several nutritional supplements (such as glucosamine sulfate and chondroitin sulfate) have been tested for potential benefit in treating osteoarthritis. So far, results are mixed, and the potential
benefit of glucosamine sulfate and chondroitin sulfate in treating pain is unclear and they do not seem to change the progression of joint damage. There is no good evidence that any other nutritional
supplements work.