Jeff Passan has noted several times this year the "epidemic" of Tommy John surgeries affecting mostly young pitchers (Jose Fernandez perhaps becoming the most recent patient).
Let me note that there are no data to back up the point I'm going to make, but that there are also no data to back up the point that Passan and others are making about the dramatic increase in elbow surgeries. But these writers are making a classic causal fallacy, quite common in both medical and innovation research.
Autism is a good example - rates of Autism have skyrocketed amongst children in the last 20 years. It could be that more kids today are indeed on the Autism spectrum, but we have also gotten much better at diagnosis - so much so that any increase could very well be completely due to advances in diagnosis and parental recognition of the signs of Autism. At this point we simply don't know if it's a spike in cases, or if it's our ability to diagnose - and we probably never will know.There are absolutely more Tommy John surgeries taking place than historically, and younger pitchers seem to be getting most of the surgeries. However, that is not evidence that more elbows are blowing out. It is evidence that we are better at both diagnosing and treating the problem. We simply have no way of knowing the rates of similar injuries in the past, because they weren't diagnosed before Tommy John, and really weren't diagnosed well until the late 1990s. We might have known about those few very good pitchers like John for whom an organization was willing to invest in costly diagnoses and surgery, but when a 22 year old minor leaguer in 1967 suddenly lost his ability to pitch and complained of elbow pain, he'd likely rest it (or maybe not rest it since it was "just" normal elbow pain), come back too quickly and have "lost his stuff" and never advanced in the system. Even an older pitcher may have had a good year or two in the Majors, but then suddenly couldn't pitch anymore, and no one could figure out why.
We'll never know if those unexplained drop-offs were elbow injuries - but I suspect, given the large number of elbow problems that we've seen since we learned to diagnose it, that these particular elbow problems have always been prevalent at pretty high rates. It's a much safer logical conclusion to say that this problem has always been around than to say that it's getting worse. We just have a better idea of what we're looking for now than we did in the past.
Passan does get one point right - there is no evidence that pitch counts and other measures are improving anything - although we know what to do about elbow problems we still don't know how to prevent them. This year is probably a statistical blip - a streak of bad luck for a lot of young pitchers, but there is no evidence that there are fewer elbow injuries over the last ten years. The search for a preventative measure seems Quixotic to me - it may just be that the human arm was not built to hurl an object at 95mph, but it might be worthwhile to spend more time studying those pitchers who do not have elbow problems in order to understand those that do.