Rheumatoid arthritis, the major crippling illness among chronic rheumatic disorders, is a systemic disease that affects many joints with an inflammatory reaction lasting months or years.
Frequently, the small joints of the hands and feet are affected first, although often the larger peripheral joints of the wrists, hips, knees, elbows, and shoulders are involved as well.
Some remissions do occur, but the illness progresses to produce damage and deformity. There is no known etiology.In 1961, the American Rheumatism Association developed a set of eight diagnostic criteria for rheumatoid arthritis suitable for epidemiological surveys. They are as follows:
1. Morning stiffness
2. Pain on motion or tenderness in at least one joint
3. Swelling (soft tissue) of at least one joint
4. Swelling of at least one Otherjoint
5. Symmetricaljointswelling
6. Nodules under the skin, typically on the surface of muscles that extend or stretch the limbs
7. Observable changes identified by X-rays, typically erosions of bone
8. Positive serologic test for rheumatoid factor
In a given patient, a definite diagnosis of rheumatoid arthritis would depend on the presence of at least five of these criteria and the absence of evidence for other rheumatic conditions. middle years. The number of new cases per 1,000 population per year ranges from 0.68 to 2.9. The prevalence of chronic arthritis in children among Caucasians is 5 percent that of adults. The mode of onset in children may vary more than that in adults, in that the simultaneous involvement of four or more joints — seen in 93 percent of the adult cases - occurs in only 30 percent of those children in whom diagnosis of rheumatoid arthritis is subsequently established.