The Pediatrician Answers:
Children also get overuse syndromes, such as carpal tunnel, but they are much rarer than in adults and usually respond quickly to simply not doing the activity. What is bad that they can get wildly out of shape because they stop exercising and get overweight because they eat as they type and this is a serious problem. Send the child outdoors whenever possible.
Children who already have emotional problems can get addicted to video games and lose both social skills (they actually have trouble interacting with other people directly) and get anesthetized to the consequences of violence, which can have tragic results.
Please see what your children are doing on the computers. You are their editor.