Osteoarthritis (AH-stee-oh-ar-THREYE-tis) is the most common type of arthritis, and is seen especially among older people.
Sometimes it is called degenerative joint disease or osteoarthrosis.
Osteoarthritis mostly affects cartilage (KAR-til-uj), the hard but slippery tissue that covers the ends of bones where they meet to form 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, small deposits of bone - called osteophytes or bone spurs - 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 some movement limitations. Unlike some other forms of arthritis, such as rheumatoid arthritis, osteoarthritis affects only joint function and does not affect skin tissue, the lungs, the eyes, or the blood vessels.
In rheumatoid arthritis, the second most common form of arthritis, the immune system attacks the tissues of the joints, leading to pain, inflammation, and eventually joint damage and malformation. It typically begins at a younger age than osteoarthritis, causes swelling and redness in joints, and may make people feel sick, tired, and uncommonly feverish.
Who Has Osteoarthritis?
Osteoarthritis is by far the most common type of arthritis, and the percentage of people who have it grows higher with age. An estimated 27 million Americans age 25 and older have osteoarthritis.
Although osteoarthritis is more common in older people, younger people can develop it - usually as the result of a joint injury, a joint malformation, or a genetic defect in joint cartilage. Both men and women have the disease. Before age 45, more men than women have osteoarthritis; after age 45, it is more common in women. It is also more likely to occur in people who are overweight and in those with jobs that stress particular joints.
As the population ages, the number of people with osteoarthritis will only grow. By 2030, 20 percent of Americans - about 72 million people - will have passed their 65th birthday and will be at high risk for the disease.
What Areas Does Osteoarthritis Affect?
Osteoarthritis most often occurs in the hands (at the ends of the fingers and thumbs), spine (neck and lower back), knees, and hips.
How Does Osteoarthritis Affect People?
People with osteoarthritis usually experience joint pain and stiffness. The most commonly affected joints are those at the ends of the fingers (closest to the nail), thumbs, neck, lower back, knees, and hips.
Osteoarthritis affects different people differently. Although in some people it progresses quickly, in most individuals joint damage develops gradually over years. In some people, osteoarthritis is relatively mild and interferes little with day-to-day-life; in others, it causes significant pain and disability.
While osteoarthritis is a disease of the joints, its effects are not just physical. In many people with osteoarthritis, lifestyle and finances also decline.
Lifestyle effects include
- feelings of helplessness
- limitations on daily activities
- job limitations
- difficulty participating in everyday personal and family joys and responsibilities.
Financial effects include
- the cost of treatment
- wages lost because of disability.
Fortunately, most people with osteoarthritis live active, productive lives despite these limitations. They do so by using treatment strategies such rest and exercise, pain relief medications, education and support programs, learning self-care, and having a "good attitude."
Osteoarthritis Basics: The Joint and Its Parts
A joint is the point where two or more bones are connected. With a few exceptions (in the skull and pelvis, for example), joints are designed to allow movement between the bones and to absorb shock from movements like walking or repetitive motions. These movable joints are made up of the following parts:
- 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 on the next page.
- Joint capsule: a tough membrane sac that encloses all the bones and other joint parts.
- Synovium (sin-O-vee-um): a thin membrane inside the joint capsule that secretes synovial fluid.
- Synovial fluid: a fluid that lubricates the joint and keeps the cartilage smooth and healthy.
A Healthy Joint
In a healthy joint, the ends of bones are encased in smooth cartilage. Together, they are protected by a joint capsule lined with a synovial membrane that produces synovial fluid. The capsule and fluid protect the cartilage, muscles, and connective tissues.
A Joint With Severe Osteoarthritis
With osteoarthritis, the cartilage becomes worn away. Spurs grow out from the edge of the bone, and synovial fluid increases. Altogether, the joint feels stiff and sore.
Ligaments, tendons, and muscles are tissues that surround the bones and joints, and allow the joints 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. Muscles are bundles of specialized cells that, when stimulated by nerves, either relax or contract to produce movement.
Cartilage: The Key to Healthy Joints
Cartilage is 65 to 80 percent water. The remaining three components - collagen, proteoglycans, and chondrocytes - are described below.
- collagen (KAHL-uh-jen): A family of fibrous proteins, collagens are the building blocks of skin, tendon, bone, and other connective tissues.
- proteoglycans (PRO-tee-uh-GLY-kanz): Made up of proteins and sugars, strands of proteoglycans interweave with collagens and form a mesh-like tissue. This allows cartilage to flex and absorb physical shock.
- chondrocytes (KAHN-druh-sytz): Found throughout the cartilage, chondrocytes are cells that produce cartilage and help it stay healthy as it grows. Sometimes, however, they release substances called enzymes that destroy collagen and other proteins. Researchers are trying to learn more about chondrocytes.
How Do You Know if You Have Osteoarthritis?
Usually, osteoarthritis comes on slowly. Early in the disease, your joints may ache after physical work or exercise. Later on, joint pain may become more persistent. You may also experience joint stiffness, particularly when you first wake up in the morning or have been in one position for a long time.
Although osteoarthritis can occur in any joint, most often it affects the hands, knees, hips, and spine (either at the neck or lower back). Different characteristics of the disease can depend on the specific joint(s) affected. For general warning signs of osteoarthritis, see the box on the next page. For information on the joints most often affected by osteoarthritis, please see the following descriptions below:
Hands: Osteoarthritis of the hands seems to have some hereditary characteristics; that is, it runs in families. If your mother or grandmother has or had osteoarthritis in their hands, you're at greater-than-average risk of having it too. Women are more likely than men to have hand involvement and, for most, it develops after menopause.
When osteoarthritis involves the hands, small, bony knobs may appear on the end joints (those closest to the nails) of the fingers. They are called Heberden's (HEBerr-denz) 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 they may ache or be stiff and numb. The base of the thumb joint also is commonly affected by osteoarthritis.
Knees: The knees are among the joints most commonly affected by osteoarthritis. Symptoms of knee osteoarthritis include stiffness, swelling, and pain, which make it hard to walk, climb, and get in and out of chairs and bathtubs. Osteoarthritis in the knees can lead to disability.
Hips: The hips are also common sites of osteoarthritis. As with knee osteoarthritis, symptoms of hip osteoarthritis include pain and stiffness of the joint itself. But sometimes pain is felt in the groin, inner thigh, buttocks, or even the knees. Osteoarthritis of the hip may limit moving and bending, making daily activities such as dressing and putting on shoes a challenge.
Spine: Osteoarthritis of the spine may show up as stiffness and pain in the neck or lower back. In some cases, arthritis-related changes in the spine can cause pressure on the nerves where they exit the spinal column, resulting in weakness or numbness of the arms and legs.
The Warning Signs of Osteoarthritis
- stiffness in a joint after getting out of bed or sitting for a long time
- swelling in one or more joints
- a crunching feeling or the sound of bone rubbing on bone
About a third of people whose x rays show evidence of osteoarthritis report pain or other symptoms. For those who experience steady or intermittent pain, it is typically aggravated by activity and relieved by rest.
If you feel hot or your skin turns red, you probably do not have osteoarthritis. Check with your doctor about other causes, such as rheumatoid arthritis.
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:
The doctor begins by asking the patient to describe the symptoms, and when and how the condition started, as well as how the symptoms have changed over time. The doctor will also ask about any other medical problems the patient and close family members have and about any medications the patient is taking. Accurate answers to these questions can help the doctor make a diagnosis and understand the impact the disease has on your life.
The doctor will check the patient's reflexes and general health, including muscle strength. The doctor will also examine bothersome joints and observe the patient's ability to walk, bend, and carry out activities of daily living.
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 often is a big difference between the severity of osteoarthritis as shown by the x ray and the degree of pain and disability felt by the patient. Also, x rays may not show early osteoarthritis damage before much cartilage loss has taken place.
Magnetic resonance imaging
Also known as an MRI, magnetic resonance imaging provides high-resolution computerized images of internal body tissues. This procedure uses a strong magnet that passes a force through the body to create these images. Doctors often use MRI tests if there is pain; if x-ray findings are minimal; and if the findings suggest damage to other joint tissues such as a ligament, or the pad of connective tissue in the knee known as the meniscus.
The doctor may order blood tests to rule out other causes of symptoms. He or she may also order a joint aspiration, which involves drawing fluid from the joint through a needle and examining the fluid under a microscope.
It usually is 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 symptoms seemingly caused by the disease actually may be due to other medical conditions. The doctor will try to find out what is causing the symptoms by ruling out other disorders and identifying conditions that may make the symptoms worse. The severity of symptoms in osteoarthritis can be influenced greatly by the patient's attitude, anxiety, depression, and daily activity level.
Four Goals of Osteoarthritis Treatment
- To control pain
- To improve joint function
- To maintain normal body weight
- To achieve a healthy lifestyle
Treatment Approaches to Osteoarthritis
- Weight control
- Rest and relief from stress on joints
- Nondrug pain relief techniques
- Medications to control pain
- Complementary and alternative therapies
How Is Osteoarthritis Treated?
Most successful treatment programs involve a combination of treatments tailored to the patient's needs, lifestyle, and health. Most programs include ways to manage pain and improve function. These can involve exercise, weight control, rest and relief from stress on joints, pain relief techniques, medications, surgery, and complementary and alternative therapies. These approaches are described below.
Research shows that exercise is one of the best treatments for osteoarthritis. Exercise can improve mood and outlook, decrease pain, increase flexibility, strengthen the heart and improve blood flow, maintain weight, and promote general physical fitness. Exercise is also inexpensive and, if done correctly, has few negative side effects. The amount and form of exercise prescribed will depend on which joints are involved, how stable the joints are, and whether a joint replacement has already been done. Walking, swimming, and water aerobics are a few popular types of exercise for people with osteoarthritis. Your doctor and/or physical therapist can recommend specific types of exercise depending on your particular situation.
On the Move: Fighting Osteoarthritis with Exercise
You can use exercises to keep strong and limber, improve cardiovascular fitness, extend your joints' range of motion, and reduce your weight. The following types of exercise are part of a well-rounded arthritis treatment plan.
- strengthening exercises: These exercises strengthen muscles that support joints affected by arthritis. They can be performed with weights or with exercise bands, inexpensive devices that add resistance.
- aerobic activities: These are exercises, such as walking or low-impact aerobics, that get your heart pumping and can keep your lungs and circulatory system in shape.
- range-of-motion activities: These keep your joints limber.
- agility exercises: These can help you maintain daily living skills.
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 pain-relieving drugs, such as analgesics or anti-inflammatories (also called NSAIDs or nonsteroidal anti-inflammatory drugs) to make exercising easier, or (2) use ice afterward.
Osteoarthritis patients who are overweight or obese should try to lose weight. Weight loss can reduce stress on weight-bearing joints, limit further injury, and increase mobility. A dietitian can help you develop healthy eating habits. A healthy diet and regular exercise help reduce weight.
Rest and relief from stress on joints
Treatment plans include regularly scheduled rest. Patients must learn to recognize the body's signals, and know when to stop or slow down. This will prevent the pain caused by overexertion. Although pain can make it difficult to sleep, getting proper sleep is important for managing arthritis pain. If you have trouble sleeping, you may find that relaxation techniques, stress reduction, and biofeedback can help, as can timing medications to provide maximum pain relief through the night.
Some people use canes to take pressure off painful joints. They may use splints or braces to provide extra support for joints and/or keep them in proper position during sleep or activity. Splints should be used only for limited periods of time because joints and muscles need to be exercised to prevent stiffness and weakness. If you need a splint, an occupational therapist or a doctor can help you get a properly fitted one.
If joint pain interferes with your ability to sleep or rest, consult your doctor.
Nondrug pain relief
People with osteoarthritis may find many nondrug ways to relieve pain. Below are some examples:
Heat and cold: Heat or cold (or a combination of the two) can be useful for joint pain. Heat can be applied in a number of different ways - with warm towels, hot packs, or a warm bath or shower - to increase blood flow and ease pain and stiffness. In some cases, cold packs (bags of ice or frozen vegetables wrapped in a towel), which reduce inflammation, 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.)
Transcutaneous electrical nerve stimulation (TENS): TENS is a technique that uses a small electronic device to direct mild electric pulses to nerve endings that lie beneath the skin in the painful area. TENS may relieve some arthritis pain. It seems to work by blocking pain messages to the brain and by modifying pain perception.
Massage: In this pain-relief approach, a massage therapist will lightly stroke and/or knead the painful muscles. This may increase blood flow and bring warmth to a stressed area. However, arthritis-stressed joints are sensitive, so the therapist must be familiar with the problems of the disease.
Medications to control pain
Doctors prescribe medicines to eliminate or reduce pain and to improve functioning. Doctors consider a number of factors when choosing medicines for their patients with osteoarthritis. These include the intensity of pain, potential side effects of the medication, your medical history (other health problems you have or are at risk for), and other medications you are taking.
Because some medications can interact with one another and certain health conditions put you at increased risk of drug side effects, it's important to discuss your medication, and health history with your doctor before you start taking any new medication, and to see your doctor regularly while you are taking medication. By working together, you and your doctor can find the medication that best relieves your pain with the least risk of side effects.
The following types of medicines are commonly used in treating osteoarthritis:
Acetaminophen: A medication commonly used to relieve pain, acetaminophen (for example, Tylenol1) is available without a prescription. It is often the first medication doctors recommend for osteoarthritis patients because of its safety relative to some other drugs and its effectiveness against pain.
Brand names included in this booklet are provided as examples only, and their inclusion does not mean that these products are endorsed by the National Institutes of Health or any other Government agency. Also, if a particular brand name is not mentioned, this does not mean or imply that the product is unsatisfactory.
NSAIDs (nonsteroidal anti-inflammatory drugs): A large class of medications useful against both pain and inflammation, (NSAIDs) 2 are staples in arthritis treatment. Aspirin, ibuprofen, naproxen, and naproxen sodium are examples of NSAIDs. They are often the first type of medication used. All NSAIDs work similarly: by blocking substances called prostaglandins that contribute to inflammation and pain. However, each NSAID is a different chemical, and each has a slightly different effect on the body.
Some NSAIDS are available over the counter, while more than a dozen others, including a subclass called COX-2 inhibitors, are available only with a prescription.
All NSAIDS can have significant side effects, and for unknown reasons, some people seem to respond better to one NSAID than another. Any person taking NSAIDS regularly should be monitored by a doctor.
Warning: NSAIDs can cause stomach irritation or, less often, they can affect kidney function. The longer a person uses NSAIDs, the more likely he or she is to have side effects, ranging from mild to serious. Many other drugs cannot be taken when a patient is being treated with NSAIDs because NSAIDs alter the way the body uses or eliminates these other drugs. Check with your health-care provider or pharmacist before you take NSAIDs. Also, NSAIDs sometimes are associated with serious gastrointestinal problems, including ulcers, bleeding, and perforation of the stomach or intestine. People over age 65 and those with any history of ulcers or gastrointestinal bleeding should use NSAIDs with caution.
Other medications: Doctors may prescribe several other medicines for osteoarthritis. They include the following:
Topical pain-relieving creams, rubs, and sprays: These products, which are applied directly to the skin over painful joints, contain ingredients that work in one of three different ways: by stimulating the nerve endings to distract the brain's attention from the joint pain; by depleting the amount of a neurotransmitter called substance P that sends pain messages to the brain; or by blocking chemicals called prostaglandins that cause pain and inflammation. Examples of topical medications are Zostrix, Icy Hot, Therapeutic Mineral Ice, Aspercreme, and Ben Gay.
Tramadol (Ultram): A prescription pain reliever that is sometimes prescribed when over-the-counter medications don't provide sufficient relief. It carries risks that don't exist with acetaminophen and NSAIDs, including the potential for addiction.
Mild narcotic painkillers: Medications containing narcotic analgesics such as codeine or hydrocodone are often effective against osteoarthritis pain. But because of concerns about the potential for physical and psychological dependence on these drugs, doctors generally reserve them for short-term use.
Corticosteroids: Corticosteroids are powerful antiinflammatory hormones made naturally in the body or man-made for use as medicine. They may be injected into the affected joints to temporarily relieve pain. This is a short-term measure, generally not recommended for more than two to four treatments per year. Oral corticosteroids are not routinely used to treat osteoarthritis. They are occasionally used for inflammatory flares.
Hyaluronic acid substitutes: Sometimes called viscosupplements, these products are designed to replace a normal component of the joint involved in joint lubrication and nutrition. Depending on the particular product your doctor prescribes, it will be given in a series of three to five injections. These products are approved only for osteoarthritis of the knee.
Because most medicines used to treat osteoarthritis have side effects, it's important to learn as much as possible about the medications you take, even the ones available without a prescription. Certain health problems and lifestyle habits can increase the risk of side effects from NSAIDs. These include a history of peptic ulcers or digestive tract bleeding, use of oral corticosteroids or anticoagulants (blood thinners), smoking, and alcohol use.
There are measures you can take to help reduce the risk of side effects associated with NSAIDs. These include taking medications with food and avoiding stomach irritants such as alcohol, tobacco, and caffeine. In some cases, it may help to take another medication along with an NSAID to coat the stomach or block stomach acids. While these measures may help, they are not always completely effective.
For many people, surgery helps relieve the pain and disability of osteoarthritis. Surgery may be performed to achieve one or more of the following:
- Removal of loose pieces of bone and cartilage from the joint if they are causing symptoms of buckling or locking
- Repositioning of bones
- Resurfacing (smoothing out) of bones.
Surgeons may replace affected joints with artificial joints called prostheses. These joints can be made from metal alloys, high-density plastic, and ceramic material. Some prostheses are joined to bone surfaces with special cements. Others have porous surfaces and rely on the growth of bone into that surface (a process called biologic fixation) to hold them in place. Artificial joints can last 10 to 15 years or longer. Surgeons choose the design and components of prostheses according to their patient's weight, sex, age, activity level, and other medical conditions.
The decision to use surgery depends on several factors, including the patient's age, occupation, level of disability, pain intensity, and the degree to which arthritis interferes with his or her lifestyle. After surgery and rehabilitation, the patient usually feels less pain and swelling, and can move more easily.
Complementary and alternative therapies
When conventional medical treatment doesn't provide sufficient pain relief, people are more likely to try complementary and alternative therapies. The following are some alternative therapies used to treat osteoarthritis.
Acupuncture: Some people have found pain relief using acupuncture, a practice in which fine needles are inserted by a licensed acupuncture therapist at specific points on the skin. Preliminary research shows that acupuncture may be a useful component in an osteoarthritis treatment plan for some patients. Scientists think the needles stimulate the release of natural, pain-relieving chemicals produced by the nervous system.
Folk remedies: These include wearing copper bracelets, drinking herbal teas, taking mud baths, and rubbing WD-40 on joints to "lubricate" them. While these practices may or may not be harmful, no scientific research to date shows that they are helpful in treating osteoarthritis. They can also be expensive, and using them may cause people to delay or even abandon useful medical treatment.
Nutritional supplements: Nutrients such as glucosamine and chondroitin sulfate have been reported to improve the symptoms of people with osteoarthritis, as have certain vitamins. Additional studies have been carried out to further evaluate these claims.
What You Can Do: The Importance of Self-Care and a Good-Health Attitude
While health care professionals can prescribe or recommend treatments to help you manage your arthritis, the real key to living well with the disease is you. Research shows that people with osteoarthritis who take part in their own care report less pain and make fewer doctor visits. They also enjoy a better quality of life.
Living well and enjoying good health despite arthritis requires an everyday lifelong commitment. Following are six habits worth committing to:
1. Get educated:
To live well with osteoarthritis, it pays to learn as much as you can about the disease. Three kinds of programs help people understand osteoarthritis, learn selfcare, and improve their good-health attitude. They are:
- Patient education programs
- Arthritis self-management programs
- Arthritis support groups.
These programs teach people about osteoarthritis, its treatments, exercise and relaxation, patient and health care provider communication, and problem solving. Research has shown that people who participate in these programs are more likely to have positive outcomes.
2. Stay active:
Regular physical activity plays a key role in self-care and wellness. Three types of exercise are important in osteoarthritis management. The first type, strengthening exercises, help keep or increase muscle strength. Strong muscles help support and protect joints affected by arthritis. The second type, aerobic conditioning exercises, improve cardiovascular fitness, help control weight, and improve overall function. The third type, range-of-motion exercises, help reduce stiffness and maintain or increase proper joint movement and flexibility.
Most people with osteoarthritis exercise best when their pain is least severe. Start with an adequate warm-up and begin exercising slowly. Resting frequently ensures a good workout and reduces the risk of injury.
Before beginning any type of exercise program, consult your doctor or physical therapist to learn which exercises are appropriate for you and how to do them correctly, because doing the wrong exercise or exercising improperly can cause problems. A health care professional can also advise you on how to warm up safely and when to avoid exercising a joint affected by arthritis.
3. Eat well:
Though no specific diet will necessarily make your arthritis better, eating right and controlling your weight can help by minimizing stress on the weightbearing joints such as the knees and the joints of the feet. It can also minimize your risk of developing other health problems.
4. Get plenty of sleep:
Getting a good night's sleep on a regular basis can minimize pain and help you cope better with the effects of your disease. If arthritis pain makes it difficult to sleep at night, speak with your doctor and/or physical therapist about the best mattress or comfortable sleeping positions or the possibility of timing medications to provide more pain relief at night. You may also improve your sleep by getting enough exercise early in the day; avoiding caffeine or alcoholic beverages at night; keeping your bedroom dark, quiet, and cool; and taking a warm bath to relax and soothe sore muscles at bedtime.
5. Have fun:
While having osteoarthritis certainly isn't fun, it doesn't mean you have to stop having fun. If arthritis makes it difficult to participate in favorite activities, ask an occupational therapist about new ways to do them. Activities such as sports, hobbies, and volunteer work can distract your mind from your own pain and make you a happier, more well-rounded person.
6. Keep a positive attitude:
Perhaps the best thing you can do for your health is to keep 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 achieve it.
Content provided by National Institute of Arthritis and Musculoskeletal and Skin Diseases