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What is 40 years patient having arthritis of PIP and DIP along with a carpometacarpal joint of the thumb and sparing of the wrist and metacarpophalangeal joint, most likely diagnosis is - and explain in detail?
Involvement of PIP, DIP and 1st Carpometacarpal joint (Carpometacarpal joint of thumb) with sparing of the wrist and the metacarpophalangeal joint is characteristic of OA.