Involvement of the joints of hand is relatively uncommon in which of the following ahritis?

Ans. is 'a' i.e., Ankylosing spondylitis Joints involved in ankylosing spondylitis Ankylosing spondylitis primarily affects axial skeleton. The disease usually begins in the sacro-iliac joints and usually extends upwards to involve the lumbar, thoracic, and often cervical spine. In the worst cases the hips or shouldersare also affected. Hip joint is the most commonly affected peripheral joint. Rarely knee and ankle are also involved.