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Handout on Health: Osteoarthritis

This booklet is for people who have osteoarthritis, their families, and others interested in learning more about the disorder. The booklet describes osteoarthritis and its symptoms and contains information about diagnosis and treatment as well as current research efforts supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) and other components of the National Institutes of Health (NIH). It also discusses pain relief, exercise, and quality of life for people with osteoarthritis. If you have further questions after reading this booklet, you may wish to discuss them with your doctor.

What Is Osteoarthritis?

Osteoarthritis (AH-stee-oh-ar-THREYE-tis) is the most common type of arthritis, especially among older people. Sometimes it is called degenerative joint disease or osteoarthrosis.

Osteoarthritis is a joint disease that mostly affects the cartilage (KAR-til-uj). Cartilage is the slippery tissue that covers the ends of bones in a joint. Healthy cartilage allows bones to glide over one another. It also absorbs energy from the shock of physical movement. In osteoarthritis, the surface layer of cartilage breaks down and wears away. This allows bones under the cartilage to rub together, causing pain, swelling, and loss of motion of the joint. Over time, the joint may lose its normal shape. Also, bone spurs--small growths called osteophytes--may grow on the edges of the joint. Bits of bone or cartilage can break off and float inside the joint space. This causes more pain and damage.

People with osteoarthritis usually have joint pain and limited movement. Unlike some other forms of arthritis, osteoarthritis only affects joints, and not internal organs. For example, rheumatoid arthritis--the second most common form of arthritis--affects other parts of the body besides the joints. It begins earlier than osteoarthritis, causes inflammation, and may make people feel sick, tired, and sometimes feverish.

Who Has Osteoarthritis?

Osteoarthritis is one of the most frequent causes of physical disability among adults. More than 20 million people in the United States probably have the disease. Some younger people get osteoarthritis from a joint injury, but osteoarthritis most often occurs in older people. In fact, by age 65, more than half of the population has x-ray evidence of osteoarthritis in at least one joint. Since the number of older Americans is increasing, so is the number of people with osteoarthritis. Both men and women have the disease. Before age 45, more men have it, while after age 45 osteoarthritis is more common in women.

How Does Osteoarthritis Affect People?

Osteoarthritis affects each person differently. In some people, it progresses more quickly; in others, the symptoms are more serious. Scientists do not yet know what causes the disease, but they suspect a combination of factors in the body and in the environment. Also, diet, weight, and stresses on the joints from certain jobs affect the disease and how a person reacts to it.

Osteoarthritis hurts people in more than their joints: their finances and lifestyles are also affected.

Financial effects include:

  • The cost of treatment
  • Wages lost because of disability.

Lifestyle effects include

  • Depression
  • Anxiety
  • Feelings of helplessness
  • Limits on daily activities
  • Job limitations
  • Loss of everyday family joys and responsibilities.

Despite these challenges, most people with osteoarthritis can lead active and productive lives. They succeed by using osteoarthritis treatment strategies such as:

  • Pain relief medications
  • Rest and exercise
  • Patient education and support programs
  • Learning self-care and having a "good-health attitude."

Osteoarthritis Basics: The Joint and Its Parts

Most joints--the place where two moving bones come together--are designed to protect bone ends from wearing away and to absorb shock from movements like walking or repetitive movements. The joint includes

  • Cartilage. A hard but slippery coating on the end of each bone. Cartilage, which breaks down and wears away in osteoarthritis, is described in more detail in the box below.
  • Joint capsule. A tough membrane sac that holds all the bones and other joint parts together.
  • Synovium (sin-O-vee-um). A thin membrane inside the joint capsule.
  • Synovial fluid. A fluid that lubricates the joint and keeps the cartilage smooth and healthy.
  • Muscles, ligaments, and tendons. Together, muscles and connective tissues keep the bones stable and allow the joint to bend and move. Ligaments are tough, cord-like tissues that connect one bone to another. Tendons are tough, fibrous cords that connect muscles to bones.

How Do You Know If You Have Osteoarthritis?

Usually, osteoarthritis comes on slowly. Early in the disease, joints may ache after physical work or exercise. Osteoarthritis can occur in any joint. Most often it occurs at the hands, hips, knees, or spine.

Hands: Osteoarthritis of the fingers is the one type of the disease that seems to be hereditary; that is, it runs in families. More women than men have it, especially after menopause. Small, bony knobs appear on the end joints of the fingers. They are called Heberden's nodes. Similar knobs (called Bouchard's [boo-SHARDZ] nodes) can appear on the middle joints of the fingers. Fingers can become enlarged and gnarled, and may ache or be stiff and numb. The base of the thumb joint is also commonly affected by osteoarthritis. This kind of osteoarthritis can be helped by medications, splints, or heat treatment.

Cartilage: the Key to Healthy Joints

Cartilage is 65 to 80 percent water. Three other substances make up the rest of cartilage tissue: collagen, proteoglycans, and chondrocytes.

  • Collagen (KAHL-uh-jen). A fibrous protein. Collagen is also the building block of skin, tendon, bone, and other connective tissues.
  • Proteoglycans (PRO-tee-uh-GLY-kanz). A combination of proteins and sugars. Strands of proteoglycans and collagen weave together and form a mesh-like tissue. This allows cartilage to flex and absorb physical shock.
  • Chondrocytes (KAHN-druh-sytz). Cells that grow all through the cartilage. They mainly help cartilage stay healthy and grow. Sometimes, however, they release substances called enzymes that destroy collagen and other proteins. Researchers are trying to learn more about chondrocytes.

Knees: The knees are the body's primary weight-bearing joints. For this reason, they are among the joints most commonly affected by osteoarthritis. They may be stiff, swollen, and painful, making it hard to walk, climb, get in and out of chairs, and use bathtubs. If not treated, osteoarthritis in the knees can lead to disability. Medications, losing weight, exercise, and walking aids can reduce pain and disability. In severe cases, knee replacement surgery may be helpful.

The Warning Signs of Osteoarthritis

  • Steady or intermittent pain in a joint
  • Stiffness after getting out of bed
  • Joint swelling or tenderness in one or more joints
  • A crunching feeling or sound of bone rubbing on bone
  • Hot, red, or tender? Probably not osteoarthritis. Check with your doctor about other causes, such as rheumatoid arthritis.
  • Not always pain. Not everyone with osteoarthritis feels pain. In fact, only a third of people with osteoarthritis in their x rays report pain or other symptoms.

Hips: Osteoarthritis in the hip can cause pain, stiffness, and severe disability. People may feel the pain in their hips, or in their groin, inner thigh, or knees. Walking aids such as canes or walkers can reduce stress on the hip. Osteoarthritis in the hip may limit moving and bending. This can make daily activities such as dressing and foot care a challenge. Walking aids, medication, and exercise can help relieve pain and improve motion. The doctor may recommend hip replacement if the pain is severe and not helped by other methods.

Spine: Stiffness and pain in the neck or in the lower back can result from osteoarthritis of the spine. Weakness or numbness of the arms or legs can also result. Some people feel better when they sleep on a firm mattress or sit using back support pillows. Others find help from heat treatment or an exercise program to strengthen the back and abdominal muscles. In severe cases, the doctor may suggest surgery to reduce pain and help restore function.

How Do Doctors Diagnose Osteoarthritis?

No single test can diagnose osteoarthritis. Most doctors use a combination of the following methods to diagnose the disease and rule out other conditions:

Clinical History: The doctor begins by asking the patient to describe the symptoms, and when and how the condition started. Good doctor-patient communication is important. The doctor can give a better assessment if the patient gives a good description of pain, stiffness, and joint function, and how they changed over time. It is also important for the doctor to know how the condition is affecting the patient's work and daily life. Finally, the doctor also needs to know about other medical conditions and whether the patient is taking any medicines.

Physical Examination: The doctor will check the patient's general health. Joints bothering the patient will be examined, including checking reflexes and muscle strength. The doctor will also observe the patient's ability to walk, bend, and carry out activities of daily living.

X Rays: Doctors take x rays to see how much joint damage has been done. X rays of the affected joint can show such things as cartilage loss, bone damage, and bone spurs. But there is often a big difference between the severity of osteoarthritis that the x ray shows and the degree of pain and disability the patient has. And x rays may not show early osteoarthritis damage (before much cartilage loss has taken place).

Other Tests: The doctor may order blood tests to determine the cause of symptoms. Another common test includes "joint aspiration," where fluid is drawn from the joint for examination.

It is usually not difficult to tell if a patient has osteoarthritis. It is more difficult to tell if the disease is causing the patient's symptoms. Osteoarthritis is so common, especially in older people, that other conditions may play a role in the symptoms. The doctor will try to find out what is causing the symptoms, ruling out other disorders and identifying conditions that may make the symptoms worse. The severity of symptoms in osteoarthritis is greatly influenced by the patient's attitudes, anxiety, depression, or daily activity level.

How Is Osteoarthritis Treated?

Most successful treatment programs involve a combination of treatments tailored to the patient's needs, lifestyle, and health. Osteoarthritis treatment has four general goals:

  • Control pain through drugs and other measures.
  • Improve joint care through rest and exercise.
  • Maintain an acceptable body weight.
  • Achieve a healthy lifestyle.

Osteoarthritis treatment plans often include ways to manage pain and improve function. Such plans can involve exercise, rest and joint care, pain relief, weight control, medications, surgery, and nontraditional treatment approaches.

Exercise: Research shows that one of the best treatments for osteoarthritis is exercise. This activity can improve mood and outlook, decrease pain, increase flexibility, improve the heart and blood flow, maintain weight, and promote general physical fitness. It is also inexpensive and, if done correctly, has few negative side effects. The amount and form of exercise will depend on which joints are involved, how stable the joints are, and whether a joint replacement has already been done. (See Be a Winner! Practice Self-Care and Keep a Good-Health Attitude.)

Rest and Joint Care: Treatment plans include regularly scheduled rest. Patients must learn to recognize the body's signals, and know when to stop or slow down. This prevents pain caused by overexercising. Some patients find that relaxation techniques, stress reduction, and biofeedback help. Some use canes and splints to protect joints and take pressure off them. Splints or braces provide extra support for weakened joints. They also keep the joint in proper position during sleep or activity. Splints must be used for limited periods because joints and muscles need to be exercised to prevent stiffness and weakness. An occupational therapist or a doctor can help the patient get a properly fitting splint.

On the Move: Fighting Osteoarthritis With Exercise

You can use exercises to keep strong and limber, extend your range of movement, and reduce weight. Ask your doctor or physical therapist what exercises are best for you.

Strength: Exercise bands are inexpensive devices that add resistance.

Aerobics: Activities that keep your lungs and circulation systems in shape.

Range of Motion: These activities keep the joints limber.

Agility: Many of these exercises help you to maintain daily living skills.

Neck and Back Strength: Don't forget to keep your spine strong and limber.

Ask your doctor or physical therapist what exercises are best for you. Ask for guidelines on exercising when a joint is sore or if swelling is present. Also, check if you should (1) use drugs such as analgesics or anti-inflammatories (NSAIDs) to make exercising easier, or (2) use ice afterwards.

Pain Relief: People with osteoarthritis may have nonmedical ways to relieve pain. Patients can use warm towels, hot packs, or a warm bath or shower to apply moist heat to the joint. This can relieve pain and stiffness. In some cases, cold packs (a bag of ice or frozen vegetables wrapped in a towel) can relieve pain or numb the sore area. (Check with a doctor or physical therapist to find out if heat or cold is the best treatment.) Water therapy in a heated pool or whirlpool may also relieve pain and stiffness. For osteoarthritis in the knee, patients may wear insoles or cushioned shoes to redistribute weight and reduce joint stress.

Weight Control: Osteoarthritis patients who are overweight or obese need to lose weight. Weight loss can reduce stress on weight-bearing joints and limit further injury. A dietician can help patients develop healthy eating habits. A healthy diet and regular exercise help reduce weight.

Medicines: Doctors use medicines to eliminate or reduce pain and to improve functioning. Doctors consider a number of factors when choosing medicines for their patients with osteoarthritis. Two important factors are the nature of the pain and potential drug side effects. Patients must use medicines carefully and tell doctors about any changes that occur.

The following types of medicines are commonly used in treating osteoarthritis:

  • NSAIDs (Nonsteroidal anti-inflammatory drugs). Many NSAIDs are used to treat osteoarthritis. Patients can buy some over the counter (for example, aspirin, Advil®*, Motrin® IB, Aleve®, ketoprofen). Others need a prescription. These drugs work in a similar way: they fight inflammation or swelling and relieve pain. However, each NSAID is a different chemical, and has slightly different effects in the body.

    * Note: Brand names included in this booklet are provided as examples only. Their inclusion does not mean they are endorsed by the National Institutes of Health or any other Government agency. Also, if a certain brand name is not mentioned, this does not mean or imply that the product is unsatisfactory.

    Side effects. NSAIDs can cause stomach irritation or affect kidney function. The longer a person uses NSAIDs, the more likely he or she is to have side effects, and the more serious those effects can be. Many other drugs cannot be taken with NSAIDs, because NSAIDs alter the way the body uses or gets rid of these drugs. NSAIDs are associated with serious gastrointestinal problems, including ulcers, bleeding, and perforation. They should be used with caution in people over 65 and in those with any history of ulcers or gastrointestinal bleeding. COX-2 inhibitors. Two new NSAIDs, Celebrex® and Vioxx®, from a class of drugs known as COX-2 inhibitors, are now being used against osteoarthritis. These medicines reduce inflammation like traditional NSAIDs, but cause fewer gastrointestinal side effects.
  • Acetaminophen. A non-anti-inflammatory pain reliever (for example, Tylenol®). This drug does not irritate the stomach and is less likely than NSAIDs to cause long-term side effects. Research has shown that in many patients with osteoarthritis, acetaminophen relieves pain as effectively as NSAIDs. Warning: Patients with liver disease, heavy alcohol drinkers, and those on blood-thinning medicines should use acetaminophen with caution.
  • Other Medicines. Doctors may prescribe several other medicines for osteoarthritis. They include

    Topical pain-relieving creams, rubs, and sprays (for example, capsaicin cream) applied directly to the skin.

    Mild narcotic painkillers, which--while very effective--are addictive and rarely used.

    Corticosteroids, powerful anti-inflammatory hormones made naturally in the body or man made for use as drugs. Corticosteroids are typically injected into affected joints to relieve pain temporarily. This is a short-term measure, not recommended for more than two or three times per year.

    Hyaluronic acid, a new medicine for joint injection, used to treat osteoarthritis of the knee. This substance is a normal component of the joint, involved in joint lubrication and nutrition. Many patients experience pain relief after a series of three to five injections.

Questions to Ask Your Doctor
or Pharmacist About Medicines
  • How often should I take this medicine?
  • Should I take this medicine with food or between meals?
  • What side effects can I expect?
  • Should I take this medicine with other prescription medicines I take?
  • Should I take this medicine with the over-the-counter medicines I take?

Most medicines used to treat osteoarthritis have side effects. So it is important for patients to learn about the drugs they are taking. Even nonprescription drugs should be checked. Several groups of patients are at high risk for side effects. Those patients are people with a history of peptic ulcers or digestive tract bleeding, those taking oral corticosteroids or anticoagulants (blood thinners), those who smoke, and those who consume alcohol. Some patients may be able to help reduce side effects by taking some drugs with food. Others should avoid stomach irritants such as alcohol, tobacco, and caffeine. Some patients take other medicines to try to protect their stomachs by coating the stomach or blocking stomach acids. These measures help, but are not always completely effective.

Treatment Approaches to Osteoarthritis
  • Exercise
  • Medicines
  • Rest and joint care
  • Surgery
  • Pain relief techniques
  • Alternative therapies
  • Weight control

Surgery: For some people, surgery helps relieve the pain and disability of osteoarthritis. Surgery may be performed to

  • Resurface (smooth out) bones.
  • Reposition bones.
  • Replace joints. Surgeons may replace affected joints with artificial joints called prostheses. These joints can be made from metal alloys, high-density plastic, and ceramic material, and can be joined to bone surfaces by special cements. Artificial joints can last from 10 to 15 years or more. About 10 percent may need revision. Surgeons choose the design and components of prostheses according to their patient's weight, sex, age, activity level, and other medical conditions.
  • Remove loose pieces of bone or cartilage from the joint to improve joint function.

Health Professionals Who Treat Osteoarthritis

Many types of health professionals care for people with osteoarthritis:

  • Rheumatologists. Doctors who specialize in treating arthritis and related conditions that affect joints, muscles, and bones.
  • Orthopaedists. Doctors who specialize in treatment of and surgery for bone diseases.
  • Physical therapists. Health professionals who work with patients to improve joint function.
  • Occupational therapists. Health professionals who teach ways to protect joints, minimize pain, and conserve energy.
  • Dietitians. Health professionals who teach ways to use a good diet to improve health and maintain a healthy weight.
  • Nurse educators. Nurses who specialize in helping patients understand their overall condition and implement their treatment plans.
  • Physiatrists (rehabilitation specialists). Doctors who help patients make the most of their physical potential.
  • Licensed acupuncture therapists. Health professionals who reduce pain and improve physical functioning by inserting fine needles into the skin at various points on the body.
  • Psychologists. Health professionals who help patients cope with difficulties in the home and workplace resulting from their conditions.
  • Social workers. Professionals who assist patients with social challenges caused by disability, unemployment, financial hardships, home health care, and other needs resulting from their conditions.

The decision to use surgery depends on several things. Both surgeon and patient consider the patient's level of disability, intensity of pain, interference with lifestyle, age, and occupation. Currently, more than 80 percent of osteoarthritis surgery cases involve replacing the hip or knee joint. After surgery and rehabilitation, the patient usually feels less pain and swelling, and can move more easily.

Nontraditional Approaches: Among the alternative therapies for treating osteoarthritis are:

  • Acupuncture. Some people have found pain relief using acupuncture (the use of fine needles inserted at specific points on the skin). Preliminary research shows that acupuncture may be a useful component in an osteoarthritis treatment plan for some patients. (See the Current Research section.)
  • Folk Remedies. Some patients seek alternative therapies for their pain and disability. Some of these alternative therapies have included wearing copper bracelets, drinking herbal teas, and taking mud baths. While these practices are not harmful, some can be expensive. They also cause delays in seeking medical treatment. To date, no scientific research shows these approaches to be helpful in treating osteoarthritis.

Be a Winner! Practice Self-Care and Keep a "Good-Health Attitude"

People with osteoarthritis can enjoy good health despite having the disease. How? By learning self-care skills and developing a "good-health attitude."

Self-care is central to successfully managing the pain and disability of osteoarthritis. Patients have a much better chance for a rewarding lifestyle when they educate themselves about the disease and take part in their own care. Working actively with a team of health care providers enables people with the disease to minimize pain, share in decisionmaking about treatment, and feel a sense of control over their lives. Research shows that patients who take part in their own care report less pain and make fewer doctor visits. They also enjoy a better quality of life.

Self-Management Programs Do Help

People with osteoarthritis find that self-management programs help them:

  • Understand the disease
  • Reduce pain while remaining active
  • Cope physically, emotionally, and mentally
  • Have greater control over the disease
  • Build confidence in their ability to live an active, independent life.

Self-Help and Education Programs: Three kinds of programs help people learn about osteoarthritis, learn self-care, and improve their good-health attitude. These programs are

  • Patient education programs
  • Arthritis self-management programs
  • Arthritis support groups.

These programs teach about osteoarthritis, its treatments, exercise and relaxation, patient/health care provider communication, and problem solving. Research has shown that these programs have clear and long-lasting benefits.

Enjoy a "Good-Health Attitude"
  • Focus on your abilities instead of disabilities.
  • Focus on your strengths instead of weaknesses.
  • Break down activities into small tasks that you can manage.
  • Incorporate fitness and nutrition into daily routines.
  • Develop methods to minimize and manage stress.
  • Balance rest with activity.
  • Develop a support system of family, friends, and health professionals.

Exercise: Regular physical activity plays a key role in self-care and wellness. Two types of exercise are important in osteoarthritis management. Therapeutic exercises keep joints working as well as possible. Aerobic conditioning exercises improve strength and fitness, and control weight. Patients should be realistic when they start exercising. They should learn how to exercise correctly, because exercising incorrectly can actually cause problems.

Most people with osteoarthritis exercise best when pain is least severe. Start with an adequate warmup and begin exercising slowly. Resting frequently ensures a good workout. It also reduces the risk of injury. A physical therapist can evaluate how a patient's muscles are working. This information helps the therapist develop a safe, personalized exercise program to increase strength and flexibility.

Many people enjoy sports or other activities in their exercise program. Good activities include swimming and aquatic exercise, walking, running, biking, cross-country skiing, and using exercise machines and exercise videotapes.

People with osteoarthritis should check with their doctor or physical therapist before embarking on an exercise program. Health care providers will suggest what exercises are best for you, how to warm up safely, and when to avoid exercising a joint affected by arthritis. Pain medications and ice applications may make exercising easier.

Body, Mind, Spirit: Making the most of good health requires careful attention to the body, mind, and spirit. People with osteoarthritis must plan and develop daily routines that maximize their quality of life and minimize disability. They also need to evaluate these routines periodically to make sure they are working well.

Good health also requires a positive attitude. People must decide to make the most of things when faced with the challenges of osteoarthritis. This attitude--a good-health mindset--doesn't just happen. It takes work, every day. And with the right attitude, you will enjoy it.

Current Research

The leading role in osteoarthritis research is played by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), within the National Institutes of Health (NIH). The NIAMS funds many researchers across the United States to study osteoarthritis. It has established a Specialized Center of Research devoted to osteoarthritis. Also, a large number of researchers study arthritis at the NIAMS Multipurpose Arthritis and Musculoskeletal Disease Centers. These centers conduct basic, laboratory, and clinical research aimed at understanding the causes, treatment options, and prevention of arthritis and musculoskeletal diseases. Center researchers also study professional, patient, and public education; epidemiology; and health services.

For years, scientists thought that osteoarthritis was simply a disease of "wear and tear" that occurred in joints as people got older. In the last decade, however, research has shown that there is more to the disorder than aging alone. The production, maintenance, and breakdown of cartilage, as well as bone changes in osteoarthritis, are now seen as a series or "cascade" of events. Many researchers are trying to discover where in that cascade of events things go wrong. By understanding what goes wrong, they hope to find new ways to prevent or treat osteoarthritis. Some key areas of research are described below.

Animal Models: Animals help researchers understand how diseases work and why they occur. In osteoarthritis, animal models help researchers learn many things about osteoarthritis. They help reveal what happens to cartilage, how treatment strategies might work, and what might prevent the disease. Animal models also help scientists study osteoarthritis in very early stages, before it causes joint damage.

Diagnostic Tools: Some scientists want to find ways to detect osteoarthritis at earlier stages so that they can treat it earlier. They seek specific abnormalities in the blood, joint fluid, or urine of people with the disease. Other scientists use new technologies to analyze differences in cartilage from different joints. For example, many people have osteoarthritis in the knees or hips, but few have it in their ankles. Can ankle cartilage be different? Does it age differently? Answering these questions will help us understand the disease better.

Genetic Studies: Researchers suspect that inheritance plays a role in 25 to 30 percent of osteoarthritis cases. Scientists have identified a mutation (a gene defect) affecting collagen, an important part of cartilage in patients with an inherited kind of osteoarthritis that starts at an early age. The mutation weakens collagen protein, which may break or tear more easily under stress. Scientists are looking for other mutations in osteoarthritis. In the future, a test to determine who carries the genetic defect (or defects) could help people reduce their risk for osteoarthritis with lifestyle adjustments.

Comprehensive Treatment Strategies: Effective treatment for osteoarthritis takes more than drugs or surgery. Getting help from a variety of care professionals can often improve patient treatment and self-care. (See Health Professionals Who Treat Osteoarthritis.) Research shows that adding patient education and social support is a low-cost, effective way to decrease pain and reduce the amount of medicine used.

Exercise plays a key part in comprehensive treatment. Researchers are studying exercise in greater detail, finding out just how to use it in treating or preventing osteoarthritis. For example, several scientists have looked at knee osteoarthritis and exercise. They have found that:

  • The level of muscle strength in the thigh muscle (quadriceps) is very important. Strengthening this muscle can relieve symptoms and prevent more damage.
  • Walking can result in better functioning and increased walking distance.
  • People with knee osteoarthritis who were active in an exercise program feel less pain. They also function better.

Research has shown that losing extra weight can help people with osteoarthritis. Most important, weight loss may reduce the risk of developing osteoarthritis of the knee in overweight or obese people.

Using NSAIDs: Many patients have pain that persists despite the use of simple pain relievers like acetaminophen. Some of these patients use NSAIDs instead. Health care providers are concerned about long-term NSAID use because dangerous side effects can result. Scientists are working to design and test new, safer NSAIDs. One example currently available is a class of drugs called COX-2 inhibitors. These medicines relieve symptoms and are less likely to produce serious side effects such as stomach ulcers and bleeding, which are associated with long-term NSAID use.

Drugs to Prevent Joint Damage: No treatment actually prevents osteoarthritis or reverses or blocks the disease process once it begins. Present treatments just relieve the symptoms. Researchers are looking for drugs that would prevent, slow down, or reverse joint damage. One experimental antibiotic drug, doxycycline, may stop certain enzymes from damaging cartilage. The drug has responded well in clinical studies, but more studies are needed. Researchers are also studying growth factors or other natural chemical messengers. These potential medicines may be able to stimulate cartilage growth or repair.

Acupuncture: Licensed acupuncture therapists insert very fine needles into the skin at various points on the body. Scientists think that the needles stimulate the release of natural, pain-relieving chemicals produced by the brain or the nervous system. Researchers are looking at acupuncture treatment of patients who have knee osteoarthritis. Early findings suggest that traditional Chinese acupuncture is effective in some patients as an additional therapy for osteoarthritis, reducing pain and improving function.

Nutritional Supplements: Nutritional supplements are often reported as helpful in treating osteoarthritis. Such reports should be viewed with caution, however, since very few studies have carefully evaluated the role of nutritional supplements in osteoarthritis.

  • Glucosamine and chondroitin sulfate. Both of these nutrients are found in small quantities in food and are components of normal cartilage. Scientific studies on these two nutritional supplements have not yet shown that they affect the disease. They may relieve symptoms in some patients, however. The National Center for Complementary and Alternative Medicine at NIH is supporting a clinical trial to test whether either glucosamine or chondroitin sulfate alone, or in combination with each other, reduces pain and improves function. Patients using this therapy should do so only under the supervision of their doctor, as part of an overall treatment program with exercise, relaxation, and pain relief.
  • Vitamins D and C. Progression of the disease appears to be less in patients with high levels of vitamin D or C intake. More studies are needed to confirm these reports.

Hyaluronic Acid: Injecting this substance into the knee joint provides long-term pain relief for some people with osteoarthritis. Hyaluronic acid is a natural component of cartilage and joint fluid. It lubricates and absorbs shock in the joint. The Food and Drug Administration (FDA) recently approved this therapy for patients with osteoarthritis of the knee if they do not get relief from exercise, physical therapy, or simple analgesics. Researchers are testing whether hyaluronic acid can slow down the progression of osteoarthritis.

Estrogen: In studies of older women, scientists found a lower risk of osteoarthritis in women who had used oral estrogens for hormone replacement therapy. The researchers suspect that low estrogen levels could increase risk for the disease. Further studies are needed to answer this question.

Tissue Engineering: This technology involves removing cells from the body and replacing them to improve certain body functions. NIAMS researchers are exploring three types of tissue engineering for use in treating osteoarthritis.

  • Enzyme engineering. Certain body chemicals called enzymes may help cartilage break down. Scientists are working to genetically engineer cells that would inhibit these enzymes and prevent the damage they cause. Cells are removed from the body, genetically changed, and then injected back into the affected joint. They live in the joint and protect it from damaging enzymes.
  • Cartilage cell replacement. Researchers remove cartilage cells from the patient's own joint, clone or grow new cells using tissue culture and other laboratory techniques, and inject the newly grown cells into the patient's joint. Patients with cartilage cell replacement have decreased osteoarthritis symptoms. Actual cartilage repair is limited, however.
  • Stem cell transplantation. Stem cells are primitive cells that can transform into other kinds of cells, such as muscle or bone cells. They are usually taken from bone marrow. In the future, researchers hope to insert stem cells into cartilage where they will make new cartilage. If successful, this process could be used to repair damaged cartilage and avoid the need for surgical joint replacements with metal or plastics.

Hope for the Future

Research is opening up new avenues of treatment for people with osteoarthritis. A balanced, comprehensive approach is still the key to staying active and healthy with the disease. People with osteoarthritis should combine exercise, relaxation education, social support, and medicines in their treatment strategies. Meanwhile, as scientists unravel the complexities of the disease, new treatments and prevention methods should appear. They will improve the quality of life for people with osteoarthritis and their families.

Additional Resources

National Institute of Arthritis and Musculoskeletal
and Skin Diseases Information Clearinghouse
National Institutes of Health

1 AMS Circle
Bethesda, MD 20892-3675
(301) 495-4484 or (877) 22-NIAMS (toll free)
TTY: (301) 565-2966
Fax: (301) 718-6366
World Wide Web address: http://www.niams.nih.gov/

This clearinghouse, a public service sponsored by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), provides information about various forms of arthritis and rheumatic diseases. The clearinghouse distributes patient and professional education materials and also refers people to other sources of information.

American College of Rheumatology
1800 Century Place, Suite 250
Atlanta, GA 30345
(404) 633-3777
Fax: (404) 633-1870
World Wide Web address: http://www.rheumatology.org/

This association provides referrals to rheumatologists and physical and occupational therapists who have experience working with people who have osteoarthritis. The organization also provides educational materials and guidelines.

American Academy of Orthopaedic Surgeons
P.O. Box 2058
Des Plaines, IL 60017
Phone: 800-824-BONE (2663) (free of charge)
World Wide Web address: http://www.aaos.org/

The academy provides education and practice management services for orthopaedic surgeons and allied health professionals. It also serves as an advocate for improved patient care and informs the public about the science of orthopaedics. The orthopaedist's scope of practice includes disorders of the body's bones, joints, ligaments, muscles, and tendons. For a single copy of an AAOS brochure, send a self-addressed stamped envelope to the address above or visit the AAOS Web site.

Arthritis Foundation
1330 West Peachtree Street
Atlanta, GA 30309
(404) 872-7100
(800) 283-7800, or call your local chapter (listed in the telephone directory)
World Wide Web address: http://www.arthritis.org/

This is the main voluntary organization devoted to arthritis. The foundation publishes a free pamphlet on osteoarthritis and a magazine for members on arthritis and related conditions. It also provides up-to-date information on research and treatment, nutrition, alternative therapies, and self-management strategies. Chapters nationwide offer exercise programs, classes, support groups, physician referral services, and free literature.

Acknowledgments

The NIAMS gratefully acknowledges the assistances of John Klippel, M.D., and Joan McGowan, Ph.D., NIAMS, NIH; Kenneth D. Brandt, M.D., Indiana University School of Medicine, Indianapolis; Marc C. Hochberg, M.D., M.P.H., University of Maryland, Baltimore; and Roland Moskowitz, M.D., University Hospital of Cleveland, Ohio, in preparation and review of this publication. Special thanks also go to the patients who reviewed this publication and provided valuable input. Debbie Novak of Johnson, Bassin, and Shaw, Inc. wrote this booklet.

About NIAMS and Its Clearinghouse: The mission of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) is to support research into the causes, treatment, and prevention of arthritis and musculoskeletal and skin diseases; the training of basic and clinical scientists to carry out this research; and the dissemination of information on research progress in these diseases. The NIAMS Information Clearinghouse is a public service sponsored by the NIAMS that provides health information and information sources. Additional information and research updates can be found on the NIAMS Web site at http://www.niams.nih.gov/hi/.

This is a publication of the National Institutes of Health National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS).

This booklet is not copyrighted. Readers are encouraged to duplicate and distribute as many copies as needed.

Additional copies of this booklet are available from the

National Institute of Arthritis and Musculoskeletal
and Skin Diseases Information Clearinghouse
National Institutes of Health (NIAMS/NIH)
1 AMS Circle
Bethesda, MD 20892-3675

Publication Date: June 1999
Updated February 2000

NIH Publication No. 99-4617