juergensen posted:What changed in youth baseball in those 20 years to account for this astronomical increase in Tommy John surgeries among teenagers?
The increase is really irreverent. There were less than 100 UCLR procedures performed before 1995, and it wasn't covered by most private health insurance plans at the time. For perspective, the percent increase from 1995 to 2017 for players after being drafted is something like 900%.
I think the study you're referring to covered the period 2007-2011. I don't know of a more recent one. The total number of procedures performed alone is worrisome (790), but I would speculate that the teenager part of that group is due to 1) wide availability of the surgery to teenagers (covered by most private health insurance), 2) increase in number of players who pitch >6 months/year, and 3) better training/conditioning that allows pitchers to throw harder.