An American study has found osteoarthritis is more common in hands of sufferers who use chopsticks. David Hunter, of Boston University School of Medicine, interviewed more than 2,500 Beijingers aged over 60. He found that the hand controlling the chopsticks and the fingers used to manoeuvre the food suffer the most. The thumb, and second and third joints are the worse hit. However, he said it did not lead to a serious problem and doubts his discoveries would encourage anyone switching to knife and fork.