A 55-year-old man with long-standing psoriasis has progressive shortening and telescoping of the right index finger. Radiograph of the hand shows osteolysis of the phalanges with a 'pencil-in-cup' deformity. Which pattern of psoriatic arthritis is this?
- A Arthritis mutilans ✓
- B Symmetric polyarthritis mimicking rheumatoid arthritis
- C Distal interphalangeal predominant arthritis
- D Ankylosing spondylitis pattern
Correct answer: A. Arthritis mutilans
Explanation
Arthritis mutilans is the most destructive pattern of psoriatic arthritis, marked by gross osteolysis of phalanges producing the pencil-in-cup appearance on radiograph and clinically by telescoping (opera-glass) digits, termed main en lorgnette. Distal interphalangeal predominant disease shows DIP involvement without such lysis, the rheumatoid-like pattern spares DIP joints and lacks osteolysis, and the axial pattern affects the spine and sacroiliac joints rather than causing digital dissolution.
Reference: Fitzpatrick's Dermatology, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.