Fifty years ago, a groundbreaking surgery revolutionized the world of baseball. Today, the "Tommy John" procedure has become a household name, with an alarming number of pitchers undergoing the career-saving operation. This article delves into the theories behind the near-epidemic of ulnar collateral ligament (UCL) injuries, exploring the factors that have contributed to this concerning trend.

Throwing Velocity and Overuse: The Perfect Storm for Elbow Injuries

The Throwing Volume Epidemic

The leading cause of UCL injuries in baseball players is the sheer volume of throwing during games, seasons, and years. Pitchers who pitch more innings per game, games per season, and exceed recommended pitch counts are more likely to require Tommy John surgery. Youth pitchers are particularly vulnerable, with a 21% increased likelihood of developing elbow pain when throwing between 50 and 74 pitches, and a 35% incidence when throwing between 75 and 99 pitches in a game.The billion-dollar tournament baseball industry has exacerbated this problem, leading to excessive throwing and overuse without adequate rest and recovery. The constant microtrauma to the UCL at early ages often results in pitchers being labeled as having an "old arm" due to overuse, a challenge that our young players are facing.

The Velocity Obsession

Another significant factor contributing to the high UCL injury rate is the desire to throw harder. In the MLB, the average fastball velocity has increased from 88 mph in the 1990s to 94 mph in 2024. This trend has trickled down to the college, high school, and even little league levels, as scouts and coaches prioritize raw velocity over other pitching skills.Overhand throwing, by nature, puts valgus stress on the elbow, with forces at the elbow reaching up to 75% of the pitcher's body weight during throwing. The stress on the elbow exponentially increases with throwing velocity, as the "Tommy John Ligament" (ulnar collateral ligament, UCL) is tasked with holding the elbow together during this throwing motion.

The Shift in Pitching Strategies

The desire to increase velocity and spin rate has led to a shift in pitching strategies, with a push towards "redlining" – throwing hard for a short duration. This high-intensity effort over a short period exposes the UCL ligament to excessive stress, as pitchers are now rarely throwing over 100 pitches or completing five innings. In contrast, in 1977, there were 907 complete games, compared to just 27 in 2024.This shift in pitching strategies, with a focus on striking out batters rather than efficient pitching, has contributed to the rise in UCL injuries. The emphasis on velocity and spin rate has come at the expense of developing a well-rounded pitching repertoire and proper mechanics.

Other Potential Factors

While throwing volume and velocity are the primary culprits, other factors may also play a role in the increase of UCL injuries. These include a lack of strength, endurance, and power in the crucial throwing muscles of the legs, trunk, and shoulder, the ban of sticky foreign substances causing pitchers to grip the baseball harder, the pitch clock causing pitchers to throw while fatigued, and poor pitching mechanics that rely less on the legs and trunk in generating power.

The Alarming Trend at the Youth Level

The impact of these factors is not limited to the professional ranks. At the youth level, baseball players are 10 times more likely to sustain a UCL injury before high school than in the 2000s. Twenty-eight percent of all youth baseball pitchers experience elbow pain during the season, a concerning statistic that highlights the need for immediate action to address this growing problem.