Arthritis: Modern Treatments for That Old Pain in the Joints

by Food and Drug Administration (FDA)

The human skeleton and muscles help to make possible the graceful gyrations of the dancer and the prowess of the athlete, as well as the many more mundane movements of our everyday lives. We tend to take for granted the normally smooth sliding motion of our joints — until it is hampered. One of the most common ills — arthritis — affects this vital function. Arthritis is a disorder of the joints, the junctions between bones.

About 50 million people in the United States have arthritis. Although many suffer only intermittently, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, the condition interferes with day-to-day activities for 4.4 million people, and causes partial disability in 1.5 million and complete disability in another 1.5 million individuals. The Arthritis Foundation estimates that 70 million person-days of missed work can be chalked up to arthritis in the United States each year, as can 500 million days of restricted activity.

Symptoms of the more than 100 types of arthritis range from minor stiffness to grave disability and deformity. Although arthritis cannot be cured, its course can be slowed and symptoms relieved. And, with increasing understanding of the disease process underlying at least some forms of the illness, the outlook for new, more effective drugs is promising.

The Synovial Joint

Arthritis affects the synovial joint, a liquid-filled capsule built of fibrous bands of connective tissue — the ligaments — that attach adjoining movable bones. The capsule is lined on the inside with a membrane that secretes the cushioning synovial fluid, which is stored in membrane-lined packets called bursae. In healthy joints between movable bones, only a thin film of synovial fluid covers the surfaces. A decrease in synovial fluid is associated with the joint stiffness that we normally feel as we age. In arthritis, the amount of synovial fluid increases, swelling the joint.

Opposing bones facing a joint are capped by cartilage, a flexible, bloodless tissue. In a healthy synovial joint, the slipperiness of the cartilage tips and the fluid in the joint allow the bones to move nearly friction-free.

Joint deterioration can be hereditary or can result from injury, infection, autoimmune disease (attack by the individual's own immune system), or even a drug reaction. Although the physical changes behind some forms of arthritis are well understood, we know relatively little about how those changes begin.

Of the more than 100 types of arthritis, by far the most prevalent are osteoarthritis (with nearly 16 million sufferers) and rheumatoid arthritis (with nearly 3 million sufferers). (See accompanying article.) It is not surprising that the rarer forms of arthritis may initially be misdiagnosed as one of these more prevalent two.

This was the case with 10-year-old Christopher Green, of Scotia, N.Y., who had a fever for two weeks and then rapidly developed near-crippling arthritis in his legs and hips. Chris's condition was first diagnosed as juvenile rheumatoid arthritis, but the appearance of other symptoms (see chart) soon led his physicians to suspect Kawasaki disease, a condition first identified in Japan in 1974, where several epidemics have occurred. Kawasaki disease includes arthritis 15 percent of the time. Chris fully recovered the use of his joints after three weeks, and his doctors do not expect the arthritis to recur — although the condition is so recently identified that they cannot be certain.

Another rare form of arthritis is on the rise. It begins with infection by Streptococcus pyogenes, also known as strep A. The incidence is 4 to 5 cases per 100,000 people, and the death rate is a whopping 20 to 25 percent.

From the initial symptoms of a sore throat and pneumonia, the illness can progress to meningitis (inflammation of the membrane covering the brain). If the patient survives, arthritis may develop.

Setting Therapy Goals

Arthritis therapy aims to protect the affected joints, maintain as much mobility as possible, and strengthen neighboring muscles to minimize loss of function. These goals can be approached by lifestyle changes, use of support devices and drugs, and, finally, by surgery.

Eating fish (such as salmon and other deep sea fish) rich in the oils eicosapentaenoic acid and ocosahexanoic acid improves symptoms of rheumatoid arthritis, says Charles Dinarello, M.D., at the Tufts University School of Medicine. "Our work on the mechanism of fish oil action suggests that its anti-inflammatory properties are at least partly due to lowering tumor necrosis factor," Dinarello says, referring to one of the immune system biochemicals that collects in rheumatoid arthritis joints.

Over the past decade, more and more rheumatologists have suggested that their patients exercise. Regular activity that does not place weight on affected joints, but strengthens surrounding bones, muscles and ligaments, can be valuable for many types of arthritis. With the help of a physical therapist, isometric and isotonic exercises and massaging can be tailored to the specific affected joints. For example, exercise that rotates the neck can relieve stiffness and pain and improve mobility in a person with an arthritic spine.

Devices and Drugs

An "activities of daily living" evaluation can help an arthritic patient identify painful movements, which will assist in the development of devices that can be used at home or in the work place. A person with arthritic hands might use extensions — long handles — on utensils and pens. Shelves can be rearranged so that the most frequently used items are within easy reach of someone with arthritic shoulders. Crutches and canes can help those with arthritic knees or hips. Special thumb, hand or wrist splints and gloves can temporarily restore hand function. Wearing loose-fitting clothes that avoid putting pressure on sensitive joints and avoiding obesity make life for the arthritic patient a little easier.

In the 1940s, it was discovered that crude extracts from adrenal glands of animals could rapidly relieve the inflammation of arthritis. In the 1950s, drug companies developed the anti-inflammatory agents cortisone and hydrocortisone. These potent drugs resemble the human adrenal hormone cortisol. But their use is limited today.

"Cortisone has adverse effects that were originally discovered in the early 1950s. It is an immune suppressant, weakening the body's defense against infections," says Dottie Pease, consumer safety officer at FDA's pilot drug evaluation department. Cortisone taken by mouth can lead to osteoporosis, and direct injection into joints can damage the cartilage. Further, it can cause cataracts, skin thinning, diabetes, fluid retention, poor wound healing, and increased susceptibility to infection. Still, cortisone can offer great, albeit temporary, relief.

About the Author

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