Osteoarthritis (OA) is the most common kind of arthritis. It is a joint disease caused by “wear and tear.” Healthy cartilage -- the firm, rubbery tissue that cushions bones at joints -- lets bones glide over one another, while cartilage absorbs energy from the movement. In OA, cartilage breaks down and wears away. As a result, the bones rub together causing pain, swelling, and stiffness.
OA may also limit the range of motion in affected joints. Most often, OA develops in the hands, knees, hips, and spine.
Both men and women get OA about equally. It is a common condition, especially as you get older. Symptoms tend to show up when people are in their 50s and 60s, although an injury to a joint or overuse, such as some athletes might have, can cause OA when you are younger. More than 20 million people in the United States have OA.
Signs and Symptoms
Signs and symptoms of OA may include the following:
- Joint pain -- often a deep, aching pain that gets worse when you move and better when you rest the joint. In severe cases, the pain may be constant.
- Stiffness in the morning or after sitting or lying down for more than 15 minutes
- Joint swelling
- Joints that are warm to the touch
- Limited range of motion
- Muscle weakness, caused by favoring the painful joint
- Growth of bony knobs near joints -- such as Heberden's nodes, in which bumps appear on the outermost finger joints
Most of the time, the cause of OA is unknown. It is associated with aging. However, metabolic, genetic, chemical, and mechanical factors can play a role in getting OA.
Risk factors for OA include:
- Being older
- Having OA run in your family
- Being overweight
- Injury to the joint
- History of inflammatory joint disease
- Metabolic or hormonal disorders, such as hemochromatosis and acromegaly
- Bone and joint disorders present at birth
- Repetitive stressful joint use, such as athletes or construction workers might have
- Deposits of uric acid crystals in joints
There is no single test to diagnose OA, so most doctors use a combination of methods to diagnose the disease and rule out other causes. A physical exam can show limited range of motion, grating of a joint with motion, joint swelling, and tenderness. An x-ray of affected joints will show loss of the joint space and, in advanced cases, wearing down of the ends of the bone and bone spurs.
You may reduce the risk of developing OA by:
- Protecting an injured joint from further damage
- Losing weight and staying at a proper weight
- Avoiding repetitive motions
While researchers are working on ways to regrow cartilage, those treatments aren’t yet available. Current goals when treating OA are to relieve pain and improve range of motion of the joint. Specific treatment depends upon which joint is affected. A combination of conventional treatment and complementary and alternative medicine (CAM) may be most effective.
These lifestyle changes may help you manage OA:
Losing weight -- Losing any extra weight helps relieve the pressure on your joints and may slow down the loss of cartilage as well as relieve pain. If you have OA and are overweight, losing weight is one of the best things you can do to help your condition.
Exercise -- Although it may seem hard to think about exercise when you are in pain, regular exercise is another good thing you can do when you have OA. Exercise strengthens the muscles so they better support your joints.
Several clinical studies show the value of exercise for people with OA. Clinical studies also suggest that in addition to reducing pain and disability, exercise improves strength, range of motion, balance and coordination, endurance, and posture.
Walking is a great exercise. If walking is too painful, try warm-water exercise. Water supports your joints and the warmth is soothing. Also, gentle range of motion exercises can increase your flexibility and decrease pain in affected joints. Your doctor may recommend physical therapy for specific joints.
Acetaminophen (Tylenol) -- relieves pain, although it does not reduce inflammation. Long-term use or high doses can cause liver damage, especially if you drink alcohol.
Non-steroidal anti-inflammatory drugs -- relieve pain and reduce inflammation and swelling. Although NSAIDs work well, long-term use can cause stomach problems, such as ulcers and bleeding and may raise your risk of heart problems. In April 2005, the U.S. Food and Drug Administration (FDA) asked drug manufacturers of NSAIDs to include a warning label on their product that alerts users of an increased risk for stomach bleeding. Over-the-counter NSAIDs include:
- Ibuprofen (Motrin, Advil)
- Naproxen (Aleve)
Stronger versions are available as prescription drugs.
Celecoxib (Celebrex) -- blocks an inflammation-promoting enzyme called COX-2. At first, researchers thought these kinds of drugs worked as well as NSAIDs, but with fewer stomach problems. However, numerous reports of heart attacks and stroke prompted the FDA to take two similar drugs off the market. Celebrex is still available and labeled with strong warnings and a recommendation that it be prescribed at the lowest possible dose for the shortest amount of time. If you are not getting pain relief from NSAIDs or cannot take them because of stomach problems, ask your doctor about the benefits and risks of Celebrex.
Corticosteroids (cortisone shot) -- injected directly into the joint to reduce inflammation and pain. Too many injections may cause joint damage, so your doctor may limit the number of treatments.
Surgery and Other Procedures
Surgery to replace or repair damaged joints may be needed in severe, debilitating cases. Surgical and other options include:
- Arthroplasty, or joint replacement -- total or partial replacement of the joint with an artificial joint
- Arthroscopic surgery to trim torn and damaged cartilage and wash out the joint
- Viscosupplementation -- injecting artificial joint fluid called hyaluronic acid into the knee to cushion the joint. May provide temporary relief pain for up to 6 months.
- Osteotomy, realigning a bone to relieve stress on the bone or joint
- Arthrodesis, surgical fusion of bones, usually in the spine
Nutrition and Dietary Supplements
Eating a balanced, healthy diet can help reduce inflammation in your body and may also help you lose weight or stay at a proper weight. These diet tips can help:
- Eat more foods that decrease inflammation, including garlic, onions, watercress, horseradish, mustard, parsley, celery, rose hips tea, pickles, lemon, and anti-inflammatory oils (found in nuts, seeds, and cold-water fish).
- Avoid refined foods, such as white breads, pastas, and sugars.
- Eat more lean meats, cold-water fish, tofu (soy, if no allergy) or beans for protein.
- Eat more fruits, vegetables, and whole grains.
- Use healthy cooking oils, such as olive oil or vegetable oil.
- Reduce or eliminate trans-fatty acids, found in commercially baked goods such as cookies, crackers, cakes, French fries, onion rings, donuts, processed foods, and margarine.
- Avoid caffeine and other stimulants, alcohol, and tobacco.
- Drink 6 - 8 glasses of filtered water daily.
- Exercise moderately, for 30 minutes daily, 5 days a week.
These specific supplements may help with OA pain:
Glucosamine/chondroitin, 500 - 1,500 mg daily, for joint health. Results from several well-designed scientific studies suggest that glucosamine supplements may work for OA, particularly OA of the knee or hip. In general, these studies suggest that glucosamine reduces pain, improves function in people with hip or knee OA, reduces joint swelling and stiffness, and provides relief from OA symptoms for up to 3 months after treatment is stopped.
- However, the largest clinical trial so far, the 2006 Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), showed conflicting and somewhat confusing results. The study of about 1,600 people with OA of the knee found that glucosamine and chondroitin did not reduce pain in the overall group. But it did seem to lessen pain among those with moderate-to-severe OA of the knee. The study has raised questions for further research. Researchers are now studying whether the glucosamine-chondroitin combination may in fact help those with more severe OA.
- Most studies have shown that glucosamine needs to be taken for 2 - 4 months before it is effective, although you may feel some improvement sooner. Glucosamine and chondroitin can be used along with nonsteroidal anti-inflammatory drugs (NSAIDs) to treat OA. Glucosamine and chondroitin can increase the risk of bleeding, especially if you already take blood-thinners such as warfarin (Coumadin) or clopidogrel (Plavix). Some doctors think glucosamine might interfere with some medications used to treat cancer. Ask your doctor before taking glucosamine and chondroitin.
Omega-3 fatty acids, such as fish oil, 1 - 2 capsules or 1 tbsp. oil daily, to help decrease inflammation. Higher doses may be used by health care providers. Omega-3 fatty acids increase the risk of bleeding, especially if you also take blood-thinners such as clopidogrel (Plavix), warfarin (Coumadin), or aspirin.
SAMe (s-adenosyl-L-methionine), 600 - 1200 mg daily. A number of studies suggest SAMe can help reduce OA pain. In one study, SAMe relieved pain as well as NSAIDs. In another study of people with knee OA, SAMe worked as well as Celebrex in lessening pain and improving joint function, although it took longer to feel the benefits. SAMe may interact with a number of drugs, including antidepressants, dextromethorphan (found in cough medicine), levodopa, meperidine (Demerol), and tramadol (Ultram). People with bipolar disorder should not take SAMe because of the risk of mania. Ask your doctor before taking SAMe.
Avocado soybean unsaponifiables (ASUs), 300 - 600 mg daily. A few preliminary studies suggest that this natural vegetable extract may help reduce the symptoms of OA and maybe even slow progression of the disease. More research is needed to know whether ASUs can actually stop joint damage. ASUs increase the risk of bleeding, especially if you also take blood-thinners such as clopidogrel (Plavix), warfarin (Coumadin), or aspirin.
Bromelain, 250 mg twice a day. This enzyme that comes from pineapples reduces inflammation. Bromelain increases the risk of bleeding, especially if you also take blood-thinners such as clopidogrel (Plavix), warfarin (Coumadin), or aspirin. People with stomach ulcers should avoid bromelain. Turmeric is sometimes combined with bromelain, because it makes the effects of bromelain stronger.
Herbs are generally available as standardized, dried extracts (pills, capsules, or tablets), teas, or tinctures or liquid extracts (alcohol extraction, unless otherwise noted). Mix liquid extracts with favorite beverage. Dose for teas is 1 - 2 heaping teaspoonfuls in a cup of water, steeped for 10 - 15 minutes (roots need longer).
- Turmeric (Curcuma longa) standardized extract, 300 mg three times a day, for pain and inflammation. Turmeric is sometimes combined with bromelain, because it makes the effects of bromelain stronger. Turmeric can increase the risk of bleeding, especially for people who take blood-thinnning medications or NSAIDs. Ask your doctor before taking turmeric.
- Cat's claw (Uncaria tomentosa) standardized extract, 30 mg three times a day, has been used traditionally for OA pain. In one study, 100 mg per day of cat’s claw taken for 4 weeks relieved pain better than a placebo. More research is needed. Do not take cat’s claw if you take medicine for high blood pressure or blood-thinning medications.
- Devil's claw (Harpagophytum procumbens) standardized extract, 100 - 200 mg one to two times daily. Devil's claw has also been used traditionally to relieve pain. One study found that more than 50% of people with OA of the knee or hip or low back pain who took devil's claw reported less pain and better mobility after 8 weeks. Devil's claw may increase the risk of bleeding, especially if you also take blood-thinners. It may also interact with several other medications, including those used to treat diabetes. Devil's claw may affect blood pressure and heart rate, so people with heart disease should ask their doctor before taking it.
- Ginger (Zingiber officinale), up to 2 g per day in divided doses, may reduce joint inflammation and pain. One study found that ginger extract blocked COX-2, a chemical in the body that causes pain. Ginger may increase the risk of bleeding, especially if you also take blood-thinners such as clopidogrel (Plavix), warfarin (Coumadin), or aspirin.
- Willow bark (Salix alba) standardized extract, 500 mg up to three times daily. Willow acts similar to aspirin. Do not take white willow if you are also taking aspirin or blood-thinners. Do not take willow bark if you are allergic to aspirin or salicylates. Willow should not be given to children under the age of 18.
- Capsaicin (Capsicum frutescens) cream, applied to the skin (topically). Capsaicin is the main component in hot chili peppers (also known as cayenne). Applied to the skin, it is believed to temporarily reduce amounts of "substance P," a chemical that contributes to inflammation and pain in arthritis. Several clinical studies have shown that capsaicin cream provided better pain relief than a placebo. But it doesn't improve joint swelling, grip strength, or function for people with OA. Pain generally starts to get better 3 - 7 days after applying the capsaicin cream to the skin.
Several controlled clinical trials suggest that the ancient Chinese practice of acupuncture works to treat OA pain. It may also help improve joint function. A few clinical studies have found that people with OA experience better pain relief and improvement in function from acupuncture than from NSAIDs such as aspiroxicam.
Although there is no evidence that chiropractic care can stop joint damage from OA, some clinical studies indicate that spinal manipulation may:
- Increase range of motion
- Restore normal movement of the spine
- Relax the muscles
- Improve joint coordination
- Reduce pain
A review of the scientific literature suggests that chiropractic, especially when combined with glucosamine supplements and stretches and exercise, helps treat OA. Chiropractors will avoid using direct thrusts or pressure on red, swollen joints.
Physical therapy can improve muscle strength and motion at stiff joints. Physical therapists have many techniques for treating OA.
Manual therapy and supervised exercise may help you put off joint replacement surgery for a time or even avoid it. In one study of people with OA of the knee, those who got manual therapy to the lumbar spine, hip, ankle, and knees showed the following improvements:
- Less stiffness
- Reduced pain
- Improved functional ability
- Improved walking distance
- Less need for knee surgery 1 year later
Balneotherapy (Hydrotherapy or spa therapy)
Balneotherapy is one of the oldest forms of therapy for pain relief for people with arthritis. The term "balneo" comes from the Latin word for bath (balneum) and refers to bathing in thermal or mineral waters. Sulfur-containing mud baths, for example, have been shown to relieve symptoms of arthritis. However, hydrotherapy, which can be performed under the guidance of certain physical therapists, is sometimes referred to with the word balneotherapy. The goals of balneotherapy for arthritis include:
- Improving range of joint motion
- Increasing muscle strength
- Eliminating muscle spasm
- Enhancing functional mobility
- Easing pain
Although balneotherapy is most often used for psoriatic or rheumatoid arthritis, some medical experts believe that it may help people with OA as well. However, one large review of clinical trials found little evidence to support its use.
Ice Massage, Transcutaneous Nerve Stimulation (TENS), and Electroacupuncture
In a well-designed trial comparing the effectiveness of TENS, electroacupuncture, and ice massage for the treatment of knee OA, each of these methods were found to:
- Reduce pain at rest
- Reduce stiffness
- Boost walking speed
- Increase quadriceps muscle strength
- Increase knee range of motion
Many physical therapists use TENS. When the nerve stimulation of TENS is applied to acupuncture points, it is called electroacupuncture.
Mechanical Aids (braces, splints)
Many mechanical devices, called orthoses, are available for people with OA to help support and protect joints. Made from lightweight metal leather, elastic, foam, and plastic, they allow some movement of the affected joint while not restricting nearby joints. For example, splints or braces help align joints and properly distribute weight. Shock-absorbing soles in shoes can help in daily activities and during exercise. Physical therapists use these mechanical aids most often to treat hands, wrists, knees, ankles, and feet. Orthoses should be custom-fitted by a physical or occupational therapist.
Although very few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following treatments to alleviate symptoms of OA based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.
Although people with OA are best treated with an individualized homeopathic remedy chosen by a professional homeopath, several trials have found that some common homeopathic combinations may be at least as effective as conventional medications for OA. Potential remedies include:
- A topical homeopathic gel containing comfrey (Symphytum officinale), poison ivy (Rhus toxicodendron), and marsh-tea (Ledum palustre)
- A combination homeopathic preparation containing R. toxicodendron., Arnica montana (arnica), Solanum dulcamara (climbing nightshade), Sanguinarra canadensis (bloodroot), and Sulphur
- A liquid homeopathic preparation containing R. toxicodendron, Causticum (potassium hydrate), and Lac vaccinum (cow's milk)
Other Common Homeopathic Remedies for OA Include:
- Calcarea carbonica (carbonate of lime or calcium carbonate)
- Bryonia (wild hops)
Chronic pain and disability can make daily life difficult. Treating the whole person and paying attention to the mind as well as the body can improve quality of life. Many people say that relaxation techniques, such as guided imagery and meditation, are an important part of their care, and help to reduce pain and other symptoms of OA.
This ancient Indian practice is well known for its physical, psychological, emotional, and spiritual benefits. In the West, it is often recommended to relieve musculoskeletal symptoms and some studies have found it can help relieve OA pain. In one clinical trial studying OA of the hand, the group practicing yoga showed less pain and better range of motion compared to those participating in non-yoga stretching and strengthening sessions. Some yoga "asanas" (postures) strengthen the quadriceps and emphasize stretching, both of which help people with OA of the knee. People with arthritis should begin asanas slowly and make sure they warm up first. Look for a reputable instructor who knows how to change postures for people with arthritis.
This ancient form of classical conditioning has been practiced in China for centuries. Like yoga, it is sometimes recommended to help relieve arthritis pain. Clinical studies have found the following benefits of tai chi:
- Improved fitness
- Stronger muscles
- Better flexibility
- Reduced percentage of body fat
- Lowered risk of falls in the elderly
In a clinical trial of people with OA of the knee or hip (ranging in age from 49 - 81), those who practiced tai chi twice a week for 3 months showed improvement compared to those in the control group. Improvement was seen in the following areas:
- Overall sense of quality of life
- Fewer feelings of stress/tension
- More satisfaction with general health
- Less fatigue
- Easier self management of arthritis symptoms
Many of the herbs used to treat OA have not been tested on pregnant women and some are known to be unsafe in pregnancy. Don't take any medication, herb, or supplement when you are pregnant without first talking to your obstetrician.
Prognosis and Complications
Complications of OA include:
- Inability to walk due to very advanced hip or knee OA
- Stomach bleeding and kidney problems from long-term NSAID use
Many people are able to control OA and prevent the condition from getting worse over time. Knee OA is still the No. 1 cause of disability in countries such as the United States. In the most advanced stages, OA can cause complete cartilage loss. In some cases joint replacement may be needed. While OA can be a debilitating condition, current treatments have shown great promise in reducing pain and improving mobility.
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