Les Yamachika, age 10, of Dotham, Ala., for his question:

WHAT CAUASES ARTHRITIS?

Arthritis is an inflammation of the joints of the body. It has been estimated that more than 32 million Americans suffer from one form of arthritis or another. The disease may be caused by infections, some injuries, by aging or by entirely unknown causes. There are more than 100 types of arthritic diseases.

Arthritis can cause stiffness, swelling, soreness or pain in the joints.

Chronic arthritis is common. It has three main forms: osteoarthritis, rheumatoid arthritis and gout.

Osteoarthritis results from wear and tear on the joints. Most people over 50 years of age have osteoarthritis in some degree. It is often called "old age rheumatism."

This form of arthritis is the most common cause of painful knees, backs and fingers. But it, seldom causes crippling. Osteoarthritis is a painful nuisance to many persons because it forces them to slow down.

Treatment of osteoarthritis consists mainly of moderation of activity, use of heat, taking aspirin and, in severe cases, injections of cortisone drugs into the painful joints.

Rheumatoid arthritis is often called "the great crippler." This form of arthritis can develop in persons of any age. But it most commonly attacks middle aged persons. The disease is progressive and it causes swelling and pain. Eventually, the joints stiffen in deformed positions, producing crippling.

Gout produces swelling in the joints. Crystals of uric acid are deposited in the tissue around the joints. These deposits cause sudden attacks of swelling, particularly in the feet. The attacks of swelling, usually accompanied by pain, are called gouty arthritis.

Doctors tell us that almost everyone at some time will develop arthritis. The disease has been known throughout history.

Fever, weakness of muscles and loss of weight are common in rheumatoid arthritis. The treatment of this type of arthritis is difficult and prolonged. But, in most cases, deformity may be prevented.

Helpful treatments include a well balanced diet, adequate rest balanced with enough physical exercise to prevent stiffening, the use of heat on the joints and taking plenty of aspirin and other pain killing drugs. Some doctors have also used injections of gold salts and cortisone drugs.

In some cases, replacement of patients' joints with plastic or rubber joints enables them to move without pain.

Actually, scientists report, rheumatoid arthritis has no cure, but more than half of the patients recover eventually.

Some types of arthritis are acute, others chornic. Some are common, others rare. Some affect a single joint, others all joints. Arthritis may be associated with generalized illness, but more often it is an entity unto itself.