Which joint pattern is typical of rheumatoid arthritis?

• A. DIP joints are affected with MCP and PIP involved
• B. Wrist and ankle joints only
• C. Elbow and knee joints only
• D. MCP and PIP joints with DIP sparing

Answer: (D)

In rheumatoid arthritis, the typical joint pattern is involvement of the small joints of the hands, especially the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints, usually in a symmetric way. The distal interphalangeal (DIP) joints are usually spared. This DIP sparing helps distinguish RA from conditions like osteoarthritis, where DIP joints are often affected. So the best description is MCP and PIP involvement with DIP sparing. While RA can involve other joints such as the wrists and knees, the characteristic early pattern highlighted here is the MCP/PIP involvement with DIP sparing.