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What is Dot-Dash appearance is a feature of? and explain in detail?
Ans AThis appearance is classically described in rheumatoid arthritis. It refers to focal loss of continuity of the subchondral bone. It is seen in the radial heads of the second and third metacarpals in the hand and medial aspect of the heads of the first metatarsal and lateral aspect of the fifth metatarsal in the feet