This makes me think more than ever that it's important for youth coaches to ensure proper mechanics at a young age. You can't just count pitches - you have to teach them how to pitch the ball first. As Dr. Andrews says in the article,"The No. 1 risk factor for UCL injuries is poor mechanics. The No. 2 factor is overuse. And if you overuse with poor mechanics, you're doomed."
The place to start teaching correct mechanics may be the wall drill that Al Leiter demonstrates below. And for an example of a pitcher that did it the right way, check out this comparison of Greg Maddux and Strasburg.