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Tommy John, Japan, and the future

Are pitchers’ severe elbow sprains rarer in Japan than in MLB? If so, what is the principle issue, how might context lead to different outcomes on different sides of the Pacific, and what do these say about the future of these injuries in Japan, especially for those pitchers here who throw really hard?

Could it be that Japan is doing something right that MLB might learn from? These questions were posed recently by my podcast partner, John E. Gibson (@JBWPodcast).

One of the advantages of being independent of MLB is that Japan does things differently for different reasons. Thirty years ago, Japan was different in that complete games were still expected from every regular starting pitcher, and it was not uncommon to see a really good pitcher in a high run context throw 140 to 150 pitches three times over a 15-day span until his career was essentially over at the age of 30.

Japan is no longer an outlier in that department, but it is an outlier with a fairly fossilized six days between starts, with the starting pitcher showing up to practice the following day to make sure everything is intact, and then taking the next day off.

Travis Sawchik recently published a superb article in The Score, titled, “Velo vs. Injury: Is there a better way for pitchers?

Sawchick found minimum velocities in MLB are rising faster than maximum velocities, suggesting more maximum-effort pitches. He also stated that 37 percent of the pitchers on active MLB rosters have had Tommy John surgery.

I actually do have the material on hand in the form of html files needed to learn whether a similar phenomenon is happening in Japan, but need to write some code to capture it, so I’ll pass on that for a moment and simply make some obvious points.

  1. Severe elbow sprains that call for surgery are indeed rarer in Japan. I checked every active pitcher the first week of this season to see if he had a published record of surgery to repair an elbow ligament sprain.
  2. Dr. James Andrews, who has just retired from a career that included repairing elbow sprains, said recently that the current epidemic in America is not limited to professional pitchers, and that most of the surgeries performed, either Tommy John or his cousin “the brace,” are on high school and college pitchers.
  3. Dr. Kozo Furushima, who has performed a huge number of Tommy John surgeries in Japan, said surgeries on Japanese college pitchers are also increasing rapidly.

Japan’s TJ frequency

I went through the active pitchers for the first week of this season, and counted 143 pitchers who were whose pro careers essentially started in Japan – this includes SoftBank’s Livan Moinelo, since his pro experience in Cuba was extremely limited before playing in NPB and his teammate, Carter Stewart Jr., who turned pro here.

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Questions about Yoshinobu Yamamoto

Being at the winter meetings in Nashville allowed me to catch up with people I’d been seeing there since I first started going in 2014. With four Japanese pitchers moving to MLB this winter, there was a lot to talk about.

In the past, I’ve published injury and deactivation records of Japanese pitchers trying to play in MLB, but it has been a hectic offseason, and somehow I neglected that duty this year.

This brought a request from Eno Sarris of the Athletic::

“I’ve been furiously googling and going through your site and I can’t find anything on Yamamoto injuries — do you know off the top of your head what his major injuries were? Seems like he has a ton of innings every year except his first two?”

The answer to his injury history is that if there is one, it hasn’t been made public. The answer to his playing time requires an understanding of how NPB roster rules differ from those in MLB.

Yamamoto’s published injuries — as related to deactivations are listed below:

Continue reading Questions about Yoshinobu Yamamoto