<prompt> Swan neck deformity is seen inOsteoahritisRheumatoid ahritisPsoriatic ahritisGout  <response>: Impoant deformities of hand in RABoutonniere deformity: flexion contracture of PIP joint and extension of DIP jointSwan neck deformity: Hyperextension of PIP joint and flexion at DIP jointZ-deformity: radial detion of the wrist with ulnar detion of fingersHyperextension of 1st interphalangeal joint and flexion on MP jointRefer: Mohindras Fundamentals of Ohopedics, 2nd edition, pg no. 420 