Criteria

Description

Morning Stiffness

Morning stiffness in and around the joints, lasting at least one hour before maximal improvement.

Arthritis of 3 or more joint areas

At least 3 joint areas (out of 14 possible areas; right or left PIP, MCP, wrist, elbow, knee, ankle, MTP joints) simultaneously have had soft-tissue swelling or fluid (not bony overgrowth alone) as observed by a physician.

Arthritis of hand joints

At least one area swollen (as defined above) in a wrist, MCP, or PIP joint.

Symmetric arthritis

Simultaneous involvement of the same joint areas (as defined above) on both sides of the body (bilateral involvement of PIPs, MCPs, or MTPs, without absolute symmetry is acceptable).

Rheumatoid nodules

Subcutaneous nodules over bony prominences or extensor surfaces, or in juxta-articular regions as observed by a physician.

Serum rheumatoid factor

Demonstration of abnormal amounts of serum rheumatoid factor by any method for which the result has been positive in less than 5% of normal control subjects.

Radiographic changes

Radiographic changes typical of RA on posterior or anterior hand or wrist radiographs, which must include erosions or unequivocal bony decalcification localized in, or most marked adjacent to, the involved joints (osteoarthritis changes alone do not qualify).

*Note: For classification purposes, a patient has RA if at least four of these criteria are satisfied (the first four must have been present for at least six weeks).
**MCP - metacarpophalangeal, PIP - proximal interphalangeal, MTP - metatarsophalangeal

Information obtained from UpToDate 2003