By Eno Sarris

It's time for change in baseball. The new norm is somewhere around 50 Tommy John surgeries a year, up from about five a year in the 1990s. While major league elbows are blowing out at record rates, teenagers are throwing 194 pitches in high school games. Is there a link here? Is wear and tear the issue? How can we keep our favorite pitchers on the mound? 

First, let's establish the problem. 

There is some evidence, perhaps, that these elbow surgeries are keeping our pitchers from suffering career-ending shoulder injuries. But if you look at the days lost from shoulder and elbow injuries over the last decade-plus, you don't see shoulder issues getting a lot better, just elbow issues getting worse. Take a look at average trips to the disabled list and average days on the DL since 2002, split by elbows and shoulders.

Even if the goalposts have possibly changed, losing 50 pitchers every year across baseball is a problem. It could be a new problem, and it might be a better problem than the problems we've had before, but it's a problem nonetheless. Teams are already averaging around 10 starters per year, and if the trend continues, they will need even more just to finish the season. Even if fewer pitchers are losing careers, we can still try to focus on the fact that more pitchers are losing full seasons. 

There is a possibility that early use is factoring in here. If a high school senior is allowed to throw 194 pitches, you might have a problem. On top of singular stories such as these, today's young athletes are asked to pick a sport earlier. Scouting runs deeper than ever, so athletes need to make their decisions earlier than ever. For a potential pitcher, that means one thing: lots of pitches, starting early.

But for all the belly-aching about young players with high pitch counts, there's a place where young people throw as often as American kids, but the adults don't have Tommy John surgery as often.


In Japan, young pitchers throw insane innings all the time. Daisuke Matsuzaka famously threw 250 pitches in a high school tournament, and a young man threw 232 pitches this year. When it comes to one-game workloads, young pitchers in Japan have no peers. 

But take a look at the prevalence of Tommy John surgeries in Japan over the last two-plus seasons, thanks to this Wikipedia list translated for us by Patrick Newman. Even once adjusted for the number of teams in each league, the differences are stark.

Year TJ/Team NPB TJ/Team MLB
2012 0.833 2.30
2013 0.667 1.63
2014 0.083 1.10

So Japan has similar structures in high school and college -- with sometimes even more intense one-game workloads -- and yet in the big leagues, their elbows remain healthier. Seems fairly cut and dried. We should be looking at the Japanese pitching structure for clues. 

There are some caveats. Consider the story of Takahiro Shiomi, a young left-hander for Rakuten in Nippon Professional Baseball. Last year, Shiomi had some undefined arm issues and went on the disabled list. A year later, he came off the DL with little information about what had transpired. This isn't to say that he had surgery, or should have had surgery, or would have had surgery in America. This is to say that we don't know as much about NPB arms as we do about MLB arms.

Let's say the findings are legit and Japanese pitchers undergo Tommy John less than half as often as American ones. There are some differences between Japanese baseball and American -- and Japanese baseballs and American baseballs -- but the biggest one is obvious: Japanese teams use six-man rotations. They traditionally get five days of rest between starts, and with off days, many even get six days of rest. 

This could be the way forward for American baseball. 

You can try to enforce innings limits on young men playing for many different organizations. You can work with each one to develop best practices, and to some extent that's being done now. Even Dylan Fosnacht -- the American pitcher who threw 194 pitches -- plays in a league that has rules that keep him from pitching twice in three days. He probably won't throw again until this weekend. 

But it's easier for an organization like Major League Baseball to change rules in the major and minor leagues, where they're in control. Teams are savvy, and they've seen the research. Young starters are getting pulled earlier in games, and teams are putting their pitchers -- from Stephen Strasburg to Danny Salazar -- on innings limits in order to avoid overtaxing their pitchers. 

We do have some knowledge about the usefulness of pitch count limits and innings limits. The breakthrough piece from Rany Jazayerli and Keith Woolner found that injury rates worsened for pitchers who routinely threw big pitch counts, and that stress on an arm was exponential as those pitch counts increased. Pitcher Abuse Points became a part of the sport, and now it's big news when a pitcher throws more than 110-120 pitches in a game. Add to this finding recent evidence that limiting innings on young pitchers is useful. It's not easy to study, but it looks like innings limits and pitch counts might help in trying to keep pitchers healthy. 

Some of this research wasn't replicated when the sample was college pitchers, but we know that college pitchers pitch on the weekend, and don't usually pitch twice in a week. They're basically on the six-man rotation schedule, as they pitch once over the weekend and recover during the week. Those extra days are huge: Jake Mintz writes for Cespedes Family BBQ and pitches for Washington University in St. Louis, and says that pitching on a sore arm "forces you to tweak certain things in your mechanics" and that extra rest means "less overcompensation" and "less stress on the arm." 

There would be some ramifications from removing a reliever and going to a six-man rotation. You'd be splitting the 950 or so starters' innings among six roster slots instead of five, and some stress would spread to the bullpen. But, if the players union isn't excited about a move that might keep its players healthier, an extra roster slot could bridge the gap between the two groups. Players would appreciate an extra 30 jobs, and owners could appreciate an effort to quit losing almost a half billion in salary to the DL every year.

And, there are other things that we could learn from Japan. Former major league pitcher Brian Bannister does agree that the "extended recovery cycle" of a six-man rotation would be helpful, but he points out that there are many differences in Japan that could teach us some best practice. "The standard practice/pregame dynamic warmup is extremely thorough in both duration and number of unique motions… this makes sure the body is warm and stretched out prior to throwing," says Bannister. He also thinks that their approach to weight lifting might be more suited to the act of pitching: "The overall attitude towards weightlifting is making sure the body is strong but not in the beach muscle kind of way. I believe this keeps muscles in balance and one muscle group does not overwhelm the connective tissue of a smaller muscle group." Even the recovery phase is a little different in Japan: "the recovery process in Japan is very deliberate with massage and soaking in alternating hot/cold water common."

College pitchers enjoy having the extra day to rest. Japanese pitchers do better with that extra rest and a different approach to preparation and recovery. We know that limiting innings and pitch counts works on major league pitchers. By going to the six-man rotation, we can limit starter's innings in one fell swoop. Perhaps better elbow health would follow.

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Eno Sarris writes about baseball at FanGraphs most of the time. He also started BeerGraphs for the beer nerds out there. He doesn't always play daily fantasy, but when he does, he plays it at