Does psoriatic arthritis commonly involve the distal interphalangeal joints?

• A. No
• B. Yes
• C. Only in late disease
• D. Rarely

Answer: (B)

Psoriatic arthritis commonly involves the distal interphalangeal joints. This pattern is a well-recognized feature and helps set PsA apart from rheumatoid arthritis, which typically spares the DIP joints. DIP involvement can appear early in the disease and is often seen alongside other psoriasis-associated findings such as nail changes and dactylitis when multiple joints are involved. So the statement is true because the DIP joints are a frequent site of involvement in PsA. The other options don’t fit because DIP involvement is not rare, not confined to late disease, and it is not absent in psoriatic arthritis.