Which joints are most commonly involved in rheumatoid arthritis?

Which joints are most commonly involved in rheumatoid arthritis?

• A. PIP joints
• B. DIP joints
• C. Knee
• D. MCP joints

Answer: (D)

Rheumatoid arthritis mainly affects synovial joints, with a preference for small joints of the hands. The metacarpophalangeal joints are classically involved early, showing swelling and tenderness along with the characteristic inflammatory stiffness. The proximal interphalangeal joints are also commonly affected, but the distal interphalangeal joints are typically spared in RA, which helps distinguish it from osteoarthritis. The knee can be involved as the disease progresses, but it is not as characteristic as the hand MCP joints. So the joints most commonly involved in RA are the metacarpophalangeal joints.

Rheumatoid arthritis mainly affects synovial joints, with a preference for small joints of the hands. The metacarpophalangeal joints are classically involved early, showing swelling and tenderness along with the characteristic inflammatory stiffness. The proximal interphalangeal joints are also commonly affected, but the distal interphalangeal joints are typically spared in RA, which helps distinguish it from osteoarthritis. The knee can be involved as the disease progresses, but it is not as characteristic as the hand MCP joints. So the joints most commonly involved in RA are the metacarpophalangeal joints.