Baseball’s Pitcher Injury Epidemic Has No Implementable Fix

Eury Perez. Shane Bieber. Spencer Strider. Framber Valdez. Tejay Antone. Jonathan Loáisiga. Nick Pivetta. Blake Burkhalter. Chris Murphy. Chase Silseth.

These are the names of some of baseball’s top pitching talent. They’re also the names of pitchers who suffered elbow injuries within the last week alone.

It is well-documented that baseball is experiencing a pitcher injury crisis. But much like the proverbial frog in the simmering pot of water, this problem hasn’t just now come to the fore. Rather it has been slowly coming to a boil over the last few decades. (In the 2004 calendar year, 37 professional baseball players underwent Tommy John surgery for a rate of 0.1 per day. As of this writing, that number already sits at 17, a rate of .17 per day, placing the procedure on track for a 70% increase.)

The reasons behind the Zipper Elbow epidemic are legion. However, the main culprit, as has been shown in the research time and again, is seemingly increased throwing velocity. Toss a stone and you’re likely to strike an academic study that points to increased fastball velocity—which is often used in research as a proxy for pitch repertoire velocity—as being tied to increased injury risk, particularly to the inner elbow, the location of the ulnar collateral ligament (UCL or Tommy John ligament).

If velocity is the culprit, pitching biomechanics is driving the getaway vehicle. Numerous studies have shown that landing foot placement, increased knee flexion angle of the lead leg at foot plant, increased shoulder horizontal abduction (i.e. “dragging behind”), impaired trunk and hip rotation separation, increased trunk lean, reduced shoulder rotation range of motion, and a myriad of other factors increase the torque placed on the inner elbow.

Finally, one of the best predictors of future injury is past injury, and professional pitchers are no exception. History of elbow pain is associated with future elbow injury, and specializing in baseball before age 13 is associated with a three-time increase in elbow injury and a five-time increase in shoulder injury.

The rest of the academic literature is murky at best. Tommy John surgery is known to be more common during the early months of the season but this is likely due to the increase in relative workload during Spring Training and the regular season compared to the offseason; injuries across all sports are more common as relative workloads increase dramatically. Likewise, there’s some evidence to suggest that increased innings and pitch count, both for each appearance and throughout a season, increases the risk for UCL damage. However, that data is likely heavily biased. “Good” pitchers throw harder and get better results, therefore, they pitch more, therefore, they have more opportunities to get hurt, and also place more stress on their inner elbow.

Factors such as the pitch clock, spin rates, pitch type, and grip strength either lack scientific study altogether or the data is inconclusive at best; the existing data seem to suggest they likely play some role in the development of elbow injuries, but much more research into their impact is needed to draw firm conclusions.

Where the data leaves us is snuggly between a rock and a hard place.

Taken at face value, the research suggests three ways to mitigate pitcher injury risk. The first way is to reduce pitch velocity while optimizing throwing mechanics. The second way is to prevent pitchers from specializing in baseball, especially before their teenage years and ideally before college. The third way to mitigate injury risk is for pitchers to cut down on their overall workload both in-game and in-season.

Of those options, the second is unlikely to happen without legislation as the influence of the prep showcase circuit continues to grow despite a preponderance of data displaying that participating does not increase one’s odds of landing a scholarship or getting drafted and may increase the odds of developing a UCL tear.

Reducing velocity, good luck.

“One of the few things that does have a definite positive correlation with success at the major-league level, however, is velocity. So naturally, pitchers are training to improve the thing that is most strongly correlated with success at the highest level of the game,” wrote an anonymous MLB pitcher for Baseball Prospectus earlier this year. “In the same vein, major-league hitters are very good, and so taking some off in the name of trying to stay healthy probably isn’t actually going to be a winning proposition for all but the most physically gifted of pitchers.”

As such, that has left teams to act upon the two addressable factors: reducing workload—pitchers continue to throw fewer innings each season—and maximizing biomechanical efficiency. The number of elbow injuries has continued to rise at an alarming rate. (As it turns out, fine-tuning one’s pitching mechanics is a bit of a double-edged sword. Making adjustments to the factors listed above will reduce one’s injury risk due to mechanical inefficiencies. However, reducing mechanical inefficiencies will also lead to heightened throwing velocity, potentially wiping out any defense against injury.)

So here we are. The elbow injury epidemic isn’t solely because of pitch velocity, the pitch clock, throwing mechanics, or any other single factor. It’s a complex, multifactorial phenomenon that has slowly developed over the last two decades as the greater baseball community began putting greater emphasis on throwing harder and playing year-round.

As a result, the most effective solution—reducing velocity and avoiding early sport specialization—is unimplementable, unenforceable, not in the best interest of winning, or some combination of the three. There is no antidote as baseball stands today. Expanding the number of pitchers on the 26-man roster, adjusting the pitch clock, and/or implementing six-man rotations are good ideas in theory but in practice, they’re likely just Band-Aids; all they would do is cover up the problem and perhaps prevent it from getting worse, but they likely wouldn’t result in meaningfully lower injury rates.

Velocity is the problem. Early sports specialization is the problem. But that toothpaste is already out of the tube and putting it back in may prove to be impossible, at least without implementing changes that would drastically alter the game. Unfortunately, in our quest to make the perfect pitcher, we were only concerned about if we could. We neglected to truly consider what would happen once we did.