<prompt> Swan neck deformity is seen in ?OsteoahritisRheumatoid ahritisPsoriatic ahritisGout  <response>: Ans. is b i.e., Rheumatoid ahritis Impoant deformities of hand in RA Boutonniere deformity : Flexion contracture of PIP joint and extension of DIP joint. Swan neck deformit: Hyperextension of PIP joint and flexion at DIP joint. Z-deformity : Radial detion of wrist with ulnar detion of fingers. Hyperextension of 1st interphalangeal joint and flexion of MP joint. 