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What is Ahritis mutilans is a feature of? and explain in detail?
PSORIATIC AHRITIS Classical (DIP type) most commonly involving the distal interphalangeal joints and less commonly the knees, hips, ankles, and wrists; Asymmetric oligo-aicular type (MC type) Symmetrical polyaicular type Disease limited to the spine (psoriatic spondylitis). Ahritis mutilans(X-Ray shows pencil in cup sign, pestle in moar sign)