<prompt> Primary osteoahritis affect all except:Hip JointKnee jointDistal interphalangeal jointMatacarpophalangeal joint  <response>: Osteoahritis involves DIP and PIP with sparing of MCP. Rheumatoid ahritis involves PIP and MCP with sparing of DIP. Osteoahritis commonly involves knee joint in India. Hip joint is rarely involved in osteoahritis. 