We are in the midst of what some would call an epidemic in baseball. We are talking about the rash of Tommy John surgeries so far in 2014. So far in 2014, there have been 36 Tommy John procedures, and we are only a quarter of the way through the season.
This surgery has been a major point of discussion in most baseball circles, with many trying to determine what causes this. Is it velocity, the number of innings thrown or is it something else?
Jon Roegele (@MLBPlayerAnalys) from Hardball Times and Beyond the Boxscore has kept a list of the known Tommy John procedures from the first one to Martin Perez's that occurred on Monday. Mr. Roegele has done a tremendous amount of work compiling his list. After Martin Perez was diagnosed with a UCL tear, the curiosity about trends with this procedure was overwhelming. I felt that a study in Tommy John surgery trends was needed. I used Mr. Roegele's list and broke it down a bit further. Lets start with what this surgery actually is.
The Tommy John or Ulnar Collateral Ligament (UCL) Reconstruction surgery is a procedure where the UCL is replaced in the elbow by a tendon from another part of the body, usually the leg or forearm. The procedure was first performed on Dodgers' pitcher Tommy John in 1974 by the legendary Frank Jobe. Because of the success of the first surgery and the strides in medical science, there has been an explosion in the surgery. What we don't know, is how many players in the past suffered from a torn UCL and either retired or continued to play with it torn.
Let me start with a couple of caveats. First, without the work of John Roegele this would have been impossible and I thank him for making the list public. Second, this is not a perfect study in trends of Tommy John surgery as there is just too much unknown. Third, more analysis can be done from this study such as; age when the surgery occurred, the number of innings that each player threw at the professional level and their average velocity at the Major League Level (this is an unknown at the Minor League level).
There have been 690 Tommy John surgeries that are known and 641, or 92.9 percent, have been pitchers leaving, 7.1 percent as position players.
Of the pitchers, 75.5 percent have been raised on U.S. soil. Since 1974, 78.9 percent of all players have been U.S. raised. Players raised on foreign soil (to the best of our knowledge) make up the other 21.1 percent of players over the last four decades, and 24.45 percent of those pitchers have had Tommy John.
53.77 percent of Tommy John's were performed on National League players and 46.23 percent were performed on American League players.
If we look at a breakdown by decade, there have been 242 procedures in the 2010's, which is 35.07 percent of all surgeries. In the last decade there were 385, which is 55.8 percent of all Tommy John's. There has been an exponential growth in the surgery's popularity. Even if the frequency of Tommy John surgery plateaued in this decade and it occurred at its average rate, the league would be on pace for 605 procedures this decade, which would be a 57 percent increase from the 2000s.
There have been 36 TJ's, so far in 2014, which is 5.22 percent of all procedures. The most in any year was 2011 when there were 69, good for 10.0 percent of the total number of TJ surgeries.
One of the more interesting trends I discover was that of all the TJ's, 71.58 percent attended college. However, digging a little further, it was discovered that approximately 67.5 percent of MLB draftees were college players from 2004 to 2013.
From 2002 to 2005, 71 percent of all players in Major League Baseball were former college players, according to a study by Douglas Wachter. That is right in line with the 71.58 percent of Tommy John surgeries that were done on college players.
As far as foreign born players, pitchers from the Dominican Republic have had the most Tommy John surgeries at a clip of 9.56 percent. From 1990 to 2014 players from the Dominican Republic made up 8.8 percent of all MLB players.
As far as I can tell, there is no rhyme or reason to someone suffering a UCL tear. I invite you to check out the raw data provided under this link. If anyone would like to keep up the data as more Tommy John surgeries are performed, please contact me at firstname.lastname@example.org and I'll give you access to the file.
At this point I leave you to draw your own conclusions. In my opinion, there is too much that we don't know to be able to make definitive statements regarding Tommy John surgeries, but maybe you can find something with deeper analysis. Happy hunting!
Patrick Despain is the former CEO of ShutdownInning.com and is a co-host of the Pine Tar Podcast which can be found on iTunes. He can be reached at email@example.com.