We have seen the numbers of Major League Baseball pitchers who have had ulnar collateral ligament reconstruction (Tommy John surgery) increase significantly in the last few years. Maybe worse than that jump has been the increase in the number of injuries among high school aged pitchers.

What has been the cause of this spike in Tommy John surgeries? We think that overuse plays a role. Younger pitchers who throw more than 100 innings per year are far more likely to undergo shoulder or elbow surgery than young pitchers who don’t pitch so much. Likewise, playing baseball year-round at an early age is also believed to increase a player’s risk for needing Tommy John surgery later.

Here is a risk factor you might not have heard before – growing up in a warm weather area.

Growing up in a warm climate might increase your risk for Tommy John surgery.

Does where you grow up affect your risk for Tommy John surgery?

A new study published in The Orthopaedic Journal of Sports Medicine compiled the locations of the high schools for all of the pitchers who underwent Tommy John surgery between 1974 (when legendary hurler Tommy John had the surgery) to June 1, 2014. The researchers found biographical information and classified the players as those growing up in either warm-weather states or cold-weather states. If a state was located south of the 33rd parallel, it was considered a warm-weather state. This latitude was chosen because areas below it had average temperatures above freezing in January.

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The 23 warm weather states and countries included California, Texas, Florida, Georgia, Louisiana, Arizona, Hawaii, New Mexico, Mississippi, South Carolina, Alabama, Mexico, Nicaragua, Panama, Brazil, Colombia, Venezuela, Dominican Republic, Cuba, Puerto Rico, Curacao, Jamaica, and Australia.

The findings show that where an MLB pitcher grew up might influence his later chance of needing surgery.

• Among all players in MLB history, 64.5% grew up in cold-weather locations.
• Among all MLB pitchers who underwent Tommy John surgery, a significantly higher percentage (56.3%) were from warm-weather areas, compared to 43.7% from cold-weather areas.
• Also, pitchers from warmer areas had surgery at a younger average age and earlier in their MLB careers than pitchers from cold-weather locations.

Take home points about risk for Tommy John surgery

Growing up and playing youth and high school baseball in warm-weather climates seems to increase a professional pitcher’s risk for Tommy John surgery in his career. It also seems to cause UCL injury at a younger age and earlier in his professional career. Why?

The study does not look at individual pitch or inning numbers or other data from the players’ youth baseball days. It seems logical to assume, though, it is easier to play baseball year-round in warmer areas. A young athlete in a warmer geographic location can theoretically play more games and throw more pitches and innings each year.

If an athlete can pitch all year long without months off to rest his arm, he is more likely to suffer an overuse injury.

Also read:
Pitching performance suffers after Tommy John surgery
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Is young pitcher at risk for Tommy John surgery?

Many surgeons and baseball experts believe that a pitcher’s arm has a certain number of pitches or innings in it before it breaks down. This study doesn’t look at absolute numbers of pitches or innings. But if you buy into that theory, then the fact that the pitchers from warmer climates had Tommy John surgery earlier in their careers and at younger ages makes some sense.