Why You Don't Want Your Young Pitcher To Know Tommy JohnToday is Opening Day for our Colorado Rockies. But for some kids, there is no true opening day for their season. They play year-round and seem to migrate from one league and its first game to the next. And that baseball overdose can lead to more than a sore arm. As Dr. Dave Hnida reports, it’s a big reason more and more kids are having elbow surgery and hanging up their spikes.