Juvenile arthritis is a disease that occurs in children under the age of 16.
It causes pain, stiffness and swelling in one or more of the joints. This pain, stiffness and swelling is called inflammation. With juvenile arthritis the inflammation lasts longer than six weeks, and is not caused by an injury or other illness.
Juvenile arthritis may also be called childhood arthritis.
Chronic childhood arthritis, sometimes referred to as juvenile rheumatoid arthritis or juvenile chronic arthritis, is quite different from adult rheumatoid arthritis. In fact, many people have dropped the word 'rheumatoid' and now call chronic childhood arthritis juvenile arthritis, or JA.
JA is defined as continuous inflammation of one or more joints lasting at least six weeks for which no other cause can be found.