Arthritis literally means "joint inflammation" and can affect joints in any part of the body. A joint is where two or more bones come together such as the knee, shoulder or wrist. Healthy joints are covered with a sponge-like material known as cart... http://kidsinspain.es/ais/?p=1

RA is the most common type of arthritis triggered by the immune system. Rheumatoid arthritis is an inflammatory form of arthritis that causes joint pain and damage. It affects more than two million people in the United States. Rheumatoid arthritis ... http://kidsinspain.es/ais/?p=3