Arthritis 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, many researchers study arthritis at NIAMS Multipurpose Arthritis and Musculoskeletal Diseases Centers and Multidisciplinary Clinical Research 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 epidemiology, health services, and professional, patient, and public education. The NIAMS also supports multidisciplinary clinical research centers that expand clinical studies for diseases like osteoarthritis.

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. Animal models help researchers learn many things about osteoarthritis, such as 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 detectable 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 the differences between the cartilage from different joints. For example, many people have osteoarthritis in the knees or hips, but few have it in the ankles. Can ankle cartilage be different? Does it age differently? Answering these questions will help us understand the disease better.

Genetics Studies: Researchers suspect that inheritance plays a role in 25 to 30 percent of osteoarthritis cases. Researchers have found that genetics may play a role in approximately 40 to 65 percent of hand and knee osteoarthritis cases. They suspect inheritance might play a role in other types of osteoarthritis, as well. 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 gene mutations in osteoarthritis. Recently, researchers found that the daughters of women who have knee osteoarthritis have a significant increase in cartilage breakdown, thus making them more susceptible to disease. 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.

Tissue Engineering: This technology involves removing cells from a healthy part of the body and placing them in an area of diseased or damaged tissue in order to improve certain body functions. Currently, it is used to treat small traumatic injuries or defects in cartilage, and, if successful, could eventually help treat osteoarthritis. Researchers at the NIAMS are exploring three types of tissue engineering. The two most common methods being studied today include cartilage cell replacement and stem cell transplantation. The third method is gene therapy.

• Cartilage cell replacement: In this procedure, researchers remove cartilage cells from the patient's own joint and then clone or grow new cells using tissue culture and other laboratory techniques. They then inject the newly grown cells into the patient's joint. Patients with cartilage cell replacement have fewer symptoms of osteoarthritis. 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 usually are taken from bone marrow. In the future, researchers hope to insert stem cells into cartilage, where the cells 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.
• Gene therapy: Scientists are working to genetically engineer cells that would inhibit the body chemicals, called enzymes, that may help break down cartilage and cause joint damage. In gene therapy, 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.

Comprehensive Treatment Strategies: Effective treatment for osteoarthritis takes more than medicine or surgery. Getting help from a variety of care professionals often can improve patient treatment and self-care.  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 and finding out just how to use it in treating or preventing osteoarthritis. For example, several scientists have studied knee osteoarthritis and exercise. Their results included the following:

• Strengthening the thigh muscle (quadriceps) can relieve symptoms of knee osteoarthritis and prevent more damage.
• Walking can result in better functioning, and the more you walk, the farther you will be able to walk.
• 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 who already have osteoarthritis. Moreover, overweight or obese people who do not have osteoarthritis may reduce their risk of developing the disease by losing weight.

Using NSAIDs: Many people who have osteoarthritis have persistent pain despite taking simple pain relievers such as acetaminophen. Some of these patients take NSAIDs instead. Health care providers are concerned about long-term NSAID use because it can lead to an upset stomach, heartburn, nausea, and more dangerous side effects, such as ulcers.

Scientists are working to design and test new, safer NSAIDs. One example currently available is a class of selective NSAIDs called COX-2 inhibitors. Traditional NSAIDs prevent inflammation by blocking two related enzymes in the body called COX-1 and COX-2. The gastrointestinal side effects associated with traditional NSAIDs seems to be associated mainly with blocking the COX-1 enzyme, which helps protect the stomach lining. The new selective COX-2 inhibitors, however, primarily block the COX-2 enzyme, which helps control inflammation in the body. As a result, COX-2 inhibitors reduce pain and inflammation but are less likely than traditional NSAIDs to cause gastrointestinal ulcers and bleeding. However, research shows that some COX-2 inhibitors may not protect against heart disease as well as traditional NSAIDs, so check with your doctor if you have concerns.

Acupuncture: During an acupuncture treatment, a licensed acupuncture therapist inserts very fine needles into the skin at various points on the body. Scientists think the needles stimulate the release of natural, pain-relieving chemicals produced by the brain or the nervous system. Researchers are studying acupuncture treatment of patients who have knee osteoarthritis. Early findings suggest that traditional Chinese acupuncture is effective for 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 and reduce joint damage in some patients, however. The National Center for Complementary and Alternative Medicine at the NIH is supporting a clinical trial to test whether glucosamine, chondroitin sulfate, or the two nutrients in combination reduce pain and improve 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, C, E, and beta carotene: The progression of osteoarthritis may be slower in people who take higher levels of vitamin D, C, E, or beta carotene. 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) approved this therapy for patients with osteoarthritis of the knee who do not get relief from exercise, physical therapy, or simple analgesics. Researchers are presently studying the benefits of using hyaluronic acid to treat 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 having low levels of estrogen could increase the risk of developing osteoarthritis. Additional studies are needed to answer this question.

Discover How to Stop Rheumatoid Arthritis