Osteoarthritis: Symptoms and Treatment

Arthritis is one of the leading causes of pain and disability in America, and osteoarthritis (OA) is far and away the most common type. OA begins in the cartilage, the smooth, slippery tissue that covers the ends of the bones as they come together in joints. Healthy cartilage allows the joints to move smoothly and painlessly, but in OA the cartilage undergoes chemical and structural changes, then gradually wears away.

Scientists don’t fully understand what causes OA, but they have identi?ed factors that increase risk. Advancing age is the most important. Others include a family history of OA, obesity, biomechanical abnormalities that increase stress on joints, serious injuries, and certain repetitive activities such as frequent knee bending and lifting. Poor nutrition may also play a role.

Doctors can con?rm a diagnosis of OA by taking x-rays that show the typical joint space narrowing due to loss of cartilage, accompanied eventually by the increased density of the bones near the joint (sclerosis) and bone spurs (osteophytes). In some cases, blood or joint ?uid tests may be needed to rule out conditions that mimic OA. Advanced imaging techniques are sometimes important; for example, an MRI can be helpful when OA strikes the spine. But most people can diagnose their own OA based on typical symptoms, and many can treat themselves with diet, exercise, and many nonprescription medications. If these measures don’t do the trick, doctors can provide treatments that are usually quite effective.

Here are some things you should know about OA.

Location, location

Although OA can affect any joint in the body, some joints are more vulnerable than others. The ?ngers are the most frequent targets. Bone spurs in the joints at the end and in the middle of the ?ngers produce characteristic swellings that doctors call Heberden and Bouchard nodes. OA of the knees and hips is also very common; these joints are the most likely to produce severe pain and disability. The neck and low back are frequently involved and can be very troublesome. When OA strikes the feet, it often singles out the joint at the base of the big toe.

OA has its favorite targets, but it also favors certain joints by sparing them. Barring injury, the disease is uncommon in the ankles, shoulders, elbows, and wrists. Except for the thumb, the knuckles are usually unscathed.

Symptoms

Pain heads the list, but it can be quite capricious. Some people experience lots of pain even before OA has progressed enough to produce x-ray abnormalities. The reverse is also common; some patients feel little or no discomfort even though their x-rays show advanced OA. Doctors can’t accurately predict the severity of pain because they don’t fully understand its cause. Since there are no nerves in the cartilage itself, pain must emanate from the bones or from the muscles, tendons, and ligaments that surround the joint.

Like OA itself, the pain usually begins gradually. It can remain mild or can build to a disabling severity. In most cases, it is increased by physical activity and relieved by rest. If OA progresses to an advanced stage, the pain can become severe and constant, even interfering with sleep.

Although the pain is usually centered in the involved joint, it can also be referred to nearby areas. That’s par­ticularly true of the hip and spine. Hip pain may be referred to the groin, thigh, or even the knees. OA of the spine is particularly tricky since it can put pressure on nerves, causing pain that shoots down a limb or weakness in muscles that depend on the pinched nerve. These complications are best detected by MRIs and may require surgery.

A second symptom is stiffness. Morning stiffness is common, but it usually resolves within 20 minutes. Stiffness after rest (gelling) is also brief, but patients with advanced OA can be stiff and creaky for most of the day.

People who have painful joints tend to be inactive. OA patients who are sedentary tend to be stiff, which further discourages exercise. And the inactivity leads to a third symptom, muscle weakness. It’s a vicious cycle, but appropriate forms of exercise can break the chain of disability. In fact, exercise and physical therapy are important treatments for OA.

General treatment

OA is a chronic disorder. It has never been cured, and there is no well-established way to slow its progression. But therapy can provide comfort and preserve function.

Lifestyle measures should be part of every treatment program. Patients who are overweight should reduce, and everyone with OA should eat a healthful, balanced diet and maintain good general health. Because mechanical stress increases the pain of OA, patients should avoid high-impact exercise and other activities that trigger pain. Squatting and kneeling, for exam­ple, can stress the hips and knees. Short rest periods throughout the day are often bene?cial.

Physical therapists can help detect and correct glitches in posture, gait, and body mechanics. They can also supervise therapeutic exercises (discussed below), and they can work with occupational therapists to provide any assistance devices that are needed. Even simple things like well-?tting shoes with good arch supports can help. When hands are stiff or weak, electric can openers, special grips for utensils and writing implements, reachers, easily opened pill bottles, and shoes that fasten with Velcro can make a big difference.

Many patients with OA feel better after applying heat or cold. A warm shower or bath can help loosen things up in the morning, and warm packs may also promote comfort. Applying cold packs to aching joints for 10 minutes can cut down on in?ammation and pain, particularly after exercise. It’s more art than science, so people with OA can experiment with different thermal treatments, continuing any that seem to help. The same applies to ointments, sprays, and liniments that produce warming or cooling and those containing anti-in?ammatory medications. Capsaicin (Zostrix, ArthriCare) is an irritant derived from chili peppers that appears to provide relief by depleting a chemical that transmits pain from nerve endings. Three strengths are available without prescription; it causes a burning sensation and should be applied while wearing a disposable plastic glove.

Exercise

Rest makes arthritic joints feel better, but in the long run, exercise is better.

General aerobic conditioning is very important, and low-impact exercise is best. Swimming and other aquatic exercise provide cardiovascular conditioning and ?exibility training without the stress of bearing weight. Walking, biking, elliptical trainers, and rowing machines are also desirable. Gentle stretching and yoga help by improving ?exibility. Resistance exercises keep muscles strong, often taking pressure off joints. People with mild OA can get started on their own, but patients with more serious OA (or other medical problems) should be supervised by a physical therapist or skilled personal trainer.

Simple range of motion exercises can keep joints limber and are particularly helpful the ?rst thing in the morning and after prolonged inactivity. Special stretching and strengthening exercises can help speci?c types of OA; for example, quadriceps muscles strengthening has been proven to reduce the pain of OA in the knees, at least in knees that are normally aligned. Here, too, instruction and supervision are invaluable. Physical therapists can also help reduce knee pain by taping aching joints.

Medication

After decades of doubt and even division, doctors recognize that acetaminophen (Tylenol and other brands) can often reduce the pain of OA. In 1995, in fact, the American College of Rheumatology recommended aceta­minophen as the place to start when medication is needed. Begin with 650 mg three times a day, increasing to a maximum of 1,000 mg four times a day. It’s an over-the-counter medication, but people with liver disease should check with their doctors. To be safe, people who take acetaminophen regularly should keep their alcohol intake low and should eat well.

If acetaminophen fails to relieve the pain, an anti-in?ammatory medication is usually the next step. Two categories are available, the traditional nonsteroidal anti-in?ammatory drugs (NSAIDs) and the newer, more controversial selective COX-2 inhibitors (coxibs); the table (see below) lists some members of each group. Start with an NSAID; pick the least expensive preparation that works for you and use the lowest dose that provides relief. Try to reduce the dose or switch back to acetaminophen when you’re feeling better. Above all, be alert for side effects. Gastric irritation and intestinal bleeding are the most common worries; patients who are particularly vulnerable should ask their doctors about adding a proton pump inhibitor (such as omeprazole) or misoprostol (Cytotec) to reduce the risk of bleeding. Patients with high blood pressure or kidney disease require medical supervision and monitoring, as do the elderly. And in April 2005, as a result of the problems with coxibs, the FDA has required all NSAIDs except aspirin to carry “black box” warnings about cardiovascular risk on their labels. Patients who take warfarin (Coumadin) or other anticoagulants require special precautions and monitoring if they are to use these drugs at all.

Cardiovascular risks, including heart attacks and strokes, led to the demise of two popular coxibs, rofecoxib (Vioxx) and valdecoxib (Bextra). The oldest coxib, celecoxib (Celebrex) is still available by prescription; because there are concerns about its cardiovascular side effects, doctors should use it only when other treatments fail — and they should always prescribe the lowest effective dose, monitor patients regularly, and avoid the drug altogether in patients with cardiovascular disease.

Joint injections

Corticosteroids are the most powerful anti-in?ammatory drugs, but they have powerful side effects when high doses are administered for a few weeks or longer. Oral steroids may be required for advanced rheumatoid arthritis, but they should not be used for OA. However, a long-acting steroid can be injected directly into an in?amed joint, often combined with a local anesthetic. Clinical trials document substantial pain reduction, particularly for painful ?ares of knee OA, but the bene?t wears off in weeks to months. Still, if a steroid injection seems to help, it can be repeated up to three or four times in the course of a year.

Hyaluronic acid is a natural constituent of cartilage and the joint capsule, providing lubrication and elasticity. The FDA has approved injections of hyaluronic acid (Hyalgan, Synvisc) for OA of the knee. Depending on the preparation, the drug is injected once a week for three to ?ve weeks. Unfortunately, the bene?t is modest; and pain returns after several weeks or months.

Supplements

Until 1997, supplements were obscure preparations used in veterinary medicine. Then The Arthritis Cure burst on the scene, and glucosamine and chondroitin sulfate were in the big time. Doctors were skeptical of yet another unregulated dietary supplement with extravagant claims of medical bene?t. But that skepticism didn’t stop them from investigating the products. In fact, glucosamine and chondroitin are among the few supplements that have been studied carefully, and the studies do suggest that while they are far from a cure, they can reduce the pain of OA, at least in some patients.

Glucosamine and chondroitin are both present in normal cartilage. Most supplements of glucosamine are prepared from oyster and crab shells; chondroitin is usually derived from cow or shark cartilage. The products are sold separately or in combination. Manufacturers typically recommend 1,500 mg of glucosamine and/or 1,200 mg of chondroitin a day, usually divided into three doses.

Studies of these supplements vary widely in their scienti?c quality. Some, including two well-designed trials, show little bene?t; others show moderate pain relief. Still, two independent meta-analyses that selected high-quality trials for review concluded that both products could reduce the pain of OA. And two studies of glucosamine are even more hopeful. Both a 2001 study of 212 patients in Belgium and a 2002 investigation of 202 patients in the Czech Republic found that three years of therapy slowed x-ray progression of OA in the knee while reducing pain by 20%–25%. Both trials have been criticized on technical grounds, and the National Institutes of Health has begun an American trial of glucosamine in 1,600 OA patients. But if the European results are con?rmed, glucosamine would be the ?rst agent that may actually slow the progression of OA.

Both products appear safe. People who are allergic to shell?sh might be at risk for reactions to glucosamine, and diabetics should be sure that it does not elevate their blood sugar. Patients taking chondroitin and anticoagulants should be monitored to be sure the product does not produce excessive anticoagulant effect. And everyone using these products must remember that because they are exempt from FDA oversight, their actual content, purity, effectiveness, and safety cannot be assured.

Despite these uncertainties, glucosamine and chondroitin may be worth a try, together or separately, for OA that does not respond well to standard therapy. Treatment typically costs a dollar a day or more, so prolonged therapy is probably not warranted if it doesn’t seem to help in two or three months. And there is no evidence that these products are useful for any other condition.

Many other supplements have been advocated as treatments for OA. They include S-adenosyl-L-methionine (SAMe), ginger, dimethyl sulfoxide (DMSO), and cetyl myristoleate. As of early 2006, there are not enough reliable studies to permit an evaluation of the safety and effectiveness of these products.

Acupuncture

Acupuncture is among the most popular forms of alternative or complementary medicine, particularly for pain relief. Although many patients with OA turn to acupuncture when standard treatments fail, many doctors have been skeptical. Since 2004, however, three randomized clinical trials have reported that acupuncture reduces pain caused by OA of the knee. True, the bene?t wears off after treatment stops, but that’s true of all nonsurgical approaches to the disease.

Acupuncture is not for everyone, and more study is needed to evaluate its role in OA therapy. But if you’re considering acupuncture, don’t let your friends (or doctors) needle you about your decision. Remember, too, that acupuncture is more familiar than another alternative treatment that has also been reported to help reduce knee pain: leech therapy.

Surgery

In most cases, surgical treatment is reserved for patients with severe OA who have failed to improve otherwise, but surgery can usually provide important bene?ts.

Several approaches are available. Arthroscopy was very popular for OA of the knee until a 2002 trial showed it was not bene?cial. An osteotomy may help slow the progression of OA if it can remove damaged tissue without disrupting the function of the healthy structures that remain in place. Arthrodesis, joint fusion, is usually reserved for the spine or small joints of the foot, hand, or wrist; the operation reduces pain but impairs ?exibility.

The most successful operation for advanced OA is arthroplasty, total joint replacement. Arti?cial hip and knee joints were the ?rst to be developed, but arti?cial joints for ?ngers, wrists, feet, shoulders, and elbows are now available. New techniques and materials have made joint replacements highly successful, and they continue to improve. Still, the surgery is a big deal, requiring considerable rehabilitation and carrying some risk of infection, bleeding, blood clots, and technical failure. And, like the body’s natural joints, arti?cial joints tend to wear out, often in 10–15 years. New ceramic linings may be more durable, but experience is limited as of early 2006. As with so many things, timing is everything; waiting too long for a new joint causes unnecessary suffering and may alter body mechanics enough to stress other joints, but moving ahead prematurely may mean replacing the replacement in the years ahead.

New joints for old   New joints for old   Artificial joints (shown in blue) have metal shafts that are inserted into bone and anchored. At weight-bearing points, slick high-density polyethylene is used o reduce friction (like cartilage in natural joins).

Prospects

OA is as old as humankind, and as people live longer it has become more and more troublesome. But new therapies hold real promise. Scientists have begun experimenting with cartilage grafts and transplants. New medications may be able to slow its progression and provide better pain relief. And arti?cial joints are getting better all the time.

It’s encouraging progress. Still, we’d all do well to remember the basics that can help prevent OA in the ?rst place. The formula includes maintaining a healthy body weight; getting the right exercise for cardiovascular ?tness, muscular strength, and ?exibility; avoiding injuries to joints; and getting good nutrition. It’s not a guarantee against OA, but it’s a good bet for your overall health.