Pencil-in-cup deformity is seen in: (A) Rheumatoid Arthritis, (B) Psoriatic Arthritis, (C) Ankylosing spondylitis, (D) Gouty Arthritis
Answer is B. (B) Psoriatic Arthritis # Psoriatic Arthritis (PsA): The peripheral and axial arthropathies in PsA show a number of radiographic features that distinguish them from RA & AS, respectively.> Characteristics of peripheral PsA include DIP involvement, including the classic "pencil-in-cup" deformity; marginal erosions with adjacent bony proliferation ("whiskering"); small joint ankylosis; osteolysis of phalangeal and metacarpal bone, with telescoping of digits; and periostitis and proliferative new bone at sites of enthesitis> Characteristics of axial PsA include asymmetric sacroiliitis