Which pattern of joint involvement is characteristic of rheumatoid arthritis?

• A. Unilateral involvement
• B. Symmetrical involvement
• C. Involvement of only large joints
• D. No joint involvement

Answer: (B)

Rheumatoid arthritis characteristically shows symmetrical, bilateral joint involvement, especially in the small joints of the hands and wrists. This means the same joints on both sides of the body are inflamed together, reflecting a systemic autoimmune process targeting synovial tissue. The inflammation causes warmth, swelling, pain, and morning stiffness that lasts for hours and improves with activity. Over time, chronic synovitis can lead to pannus formation and joint damage, often with sparing of the distal interphalangeal joints. This symmetric pattern helps distinguish RA from conditions that tend to be unilateral or affect primarily large joints.