infielddad, I don't believe that the ASMI has done any other study on curveballs since the one I cited. Also see this, which relies on the 2011 University of North Carolina study that said overuse and not curveballs causes issues: http://www.littleleague.org/As...s/media/UNCStudy.pdf
The percentages of TJ surgeries aren't relevant. Again, as any surgery gets more successful, it will be a more recommended course of action by a physician. If it wasn't successful, the risk/reward wouldn't be worth it. So yes, percentage-wise, there will be more 16 and under pitchers getting the surgery than there was, because the surgery has a more well-defined successful outcome. If it wasn't successful, no one would recommend it for a kid, and then the percentages would be lower. [What percentage of nonprofessional athletes/kids would undergo a surgery that costs tens of thousands of dollars and involves a great degree of rehabilitation,, if it had only a 1 in a 100 chance of fixing the injury versus a 9 in 10 chance? As the result becomes more sure, the percentages opting for the fix become higher. A greater percentage of surgeries does not mean a greater percentage of problems...it could just indicate a better/"more certain" solution for the same number of problems.]
I'm quite sure that teenagers hurt their arms in the 40's, 50's and 60's too, but the percentage of TJ surgeries then was 0% because they just stopped pitching/playing baseball since there was no successful "fix" for them. I have no doubt that Dr. Andrews has seen a huge increase in surgeries on both a percentage and raw number basis, because the "cure" gets better and better as the surgery and rehab is refined and improved (allowing kids who would be out of baseball to continue).