Arthritis Arthritis Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, swelling, and decreased range of motion of the affected joints. In some types other organs are also affected. Onset can be gradual or sudden. There are over 100 types of arthritis. The most common forms are osteoarthritis (degenerative joint disease) and rheumatoid arthritis. Osteoarthritis usually occurs with age and affects the fingers, knees, and hips. Rheumatoid arthritis is an autoimmune disorder that often affects the hands and feet. Other types include gout, lupus,
Juvenile idiopathic arthritis Juvenile idiopathic arthritis Juvenile idiopathic arthritis (JIA), also known as juvenile rheumatoid arthritis, is the most common form of arthritis in children and adolescents. ("Juvenile" in this context refers to an onset before age 16, "idiopathic" refers to a condition with no defined cause, and "arthritis" is the inflammation of the synovium of a joint.) JIA is an autoimmune, noninfective, inflammatory joint disease of more than 6 weeks duration in children less than 16 years of age. The disease commonly occurs in children from the ages of 1 to 6, but it may develop as late as 15 years of