Heading a soccer ball can cause subconcussive injury

Dear Doctor: My granddaughters are absolutely crazy about soccer. They’re constantly trying to outdo each other with their maneuvers, and now one is trying to learn to “head” the ball. But isn’t that dangerous, especially for girls?

Dear Reader: We’ve long been aware of the risk of head injuries posed by activities like football, rugby, ice hockey and boxing, where jolting physical contact is liter…