Shane Bieber, Spencer Strider, Eury Pérez, Framber Valdez.
These are just some of the big-name MLB pitchers that have hit the injured list within the first month of the 2024 season. That’s not to mention stars like Gerrit Cole, Sandy Alcántara and Kodai Senga, who are all injured long-term. It feels like the sky is falling for pitchers in Major League Baseball.
The league, players’ association and fans have reacted quickly to this onslaught of strains, tears and fractures. MLB and the MLB Players’ Association issued dueling statements last week, calling out one issue or another. The MLBPA blamed the pitch clock integrated last season for the rash of fallen pitchers because it decreases recovery between pitches. MLB denied this, claiming no evidence exists for the pitch clock argument and that ever-increasing velocity and spin rates are to blame.
So what exactly is causing all this? Is no pitcher safe? Are we living in the apocalypse?
To answer that last question — no, we are not living in the apocalypse. While it may seem like pitching injuries are up dramatically in 2024, this year is not an outlier. It’s just rotten luck that so many superstars have gone down. The bad news is that this year is part of a worsening trend of increased pitcher injuries stretching back over a decade.
From 2000 to 2013, the major and minor leagues averaged 15.4 Tommy John surgeries, a procedure to repair a torn ulnar collateral ligament, through the first 100 days of the season, according to TheScore’s Travis Sawchik. That number surged to 33.3 from 2014-23. The league implemented the pitch clock in 2023, so this trend predates that.
The league has seen another trend over the past decade plus — a steady climb in average four-seam fastball velocity from 91.9 mph in 2008 to 94.2 in 2023. Hard hurlers like Edwin Diaz, Félix Bautista and Jhoan Duran, who averaged over 100 mph on his fastball last year, punctuate this upswing.
“We do know that higher velocity tends to lead to more injuries,” Dr. Justin Arner, an orthopedic surgeon at UPMC and team doctor for the Pittsburgh Steelers, said. According to Arner, throwing harder puts more strain on the “kinetic chain,” which is the full motion of a pitcher’s delivery stemming from the lower body into the core, through the shoulder and elbow and into the lower arm.
Injuries are a part of the game. Pitchers and position players alike are willing to put their bodies on the line to maximize their value. The problem is that more pitchers are getting hurt in the primes of their careers or even at the high school and youth levels. Both Shohei Ohtani and Spencer Strider, for example, are already on their second Tommy Johns.
“It’s definitely an epidemic,” Arner said. “15- to 19-year-olds make up 27% of UCL reconstructions, and that number is growing by about 10% every year.”
Even if a pitcher doesn’t get hurt in their teenage years, the built-up damage can surface at the Major League level. But why are pitchers damaging their bodies so young instead of during the latter stages of their career? According to Arner, the issue stems from overwork.
“The issue we’re having now is young kids really sub-specializing in sports, especially baseball,” Arner said. “They throw three days a week on one team. And then every other day, they’re throwing with a travel team. They’re basically throwing all year long with indoor facilities now. They’re not given enough rest.”
The standard for starters at the high school level is to pitch every fifth day. But in the merciless world of youth sports, kids will throw as often as they can to get noticed by scouts or help their team.
“I threw pretty much as often as I could,” Ben Lerner, a former youth pitcher from Livingston, New Jersey, said. “I was often the ace on teams I played on, so I would throw as often as the pitch-count limitations would allow. Later on I would throw as often as my arm pain would allow.”
Lerner pitched for several club teams in his preteen and teenage years before lingering shoulder and elbow injuries ended his playing career at the junior varsity level.
“My shoulder was my first injury, which resulted in me compensating with my form and putting more stress on my elbow,” Lerner said. “Then I went back and forth, adjusting my form to minimize pain so I could keep pitching. I’m not sure that it helped or hurt, but it kept the cycle of injuries going.”
According to Arner, to get to the top level, pitchers must focus on every muscle in the kinetic chain instead of throwing “over and over again.”
“[Some pitchers] rely much more on their shoulder with not as ideal mechanics,” Arner said. “Whereas the seasoned pitcher really works on their core and glutes and every other muscle in their body.”
The shoulder is a vital part of the kinetic chain, according to Arner, because it controls the motion of the delivery throughout the arm, including the UCL. The goal, he said, is to have mechanics that encourage fluid motion of the shoulder.
“When you have a high rate of rotational velocity, all of a sudden all that force on the shoulder stops abruptly because it’s tight in the back,” Arner said. “A more fluid motion is able to engage all the muscles in the kinetic chain and slow down the shoulder velocity over a longer period of time rather than so abruptly.”
Good form, Lerner said, should be prioritized over everything else in youth ball.
“If something unorthodox works for a [Major League] pitcher, of course, don’t change it,” Lerner said. “But when it’s a Little League pitcher, we should try to change unnecessarily stressful pitching mechanics.”
Even with perfect rest, training and mechanics, young pitchers are hard-pressed to withstand a baseball landscape that values velocity more than ever. This relentless chase won’t end anytime soon because throwing harder yields better results. Last season, batters slugged .530 on four-seam fastballs between 88 and 93 mph versus .370 on fastballs above 96 mph. That’s not to mention trendy pitches like the power changeup and sweeping slider, which puts even more strain on arms.
“I pushed myself to throw as fast as I could because I wanted to win,” Lerner said. “I wanted to throw fastballs past hitters, and especially because my fastball wasn’t super fast. I think it took a bit more effort. I loved pitching. I got a lot of satisfaction from it, and I would get amped up during games. It was against my nature to take five miles an hour off a fastball, especially in a big situation.”
One way pitchers can increase velocity is by throwing a weighted ball, but “the question is at what risk,” Arner said.
“There isn’t a lot of research behind it … but anecdotally, most of us [orthopedists] have seen more injuries with these,” Arner said. “It’s something that can be successful in increasing velocity but we want to do it in a monitored, limited way because they put so much force on the elbow and shoulder.”
Even with the risks that come with throwing unnaturally hard, you’d have a difficult time convincing a youth pitcher to take it down a gear.
“There wasn’t an explicit culture about throwing hard,” Lerner said. “But I knew that guys respected it, and of course, I wanted to look good. It was definitely something to strive for. As a pitcher, I wish I had stuck up for myself more and been more honest with coaches about how my arm felt. There is always the temptation to handle the pain and continue playing, but I wonder how things might have been different had I sought help sooner.”
Increasing velocity isn’t going away, and the solution to baseball’s pitching injury epidemic is still up in the air. Coaches and players can use a wide range of tools to analyze mechanics and perfect them from a young age, but this doesn’t fix the problem completely. Since the Statcast era began in 2014, Tommy John surgeries have only increased. The only true solution is to revert to a more holistic approach to scouting pitching talent.
Movement, ability to change speeds and location are all things scouts already look for in a pitcher. But to excel as a starter, a pitcher almost always has to have a high-heat four-seamer in their arsenal, at least as a complementary pitch to their breaking stuff. Of the top 10 starters by ERA in 2023, six of them had an average fastball velocity over 94 mph. Of the top 10 closers by saves, seven of them threw a fastball above 94 mph.
Pitchers won’t throw less hard as long as teams value velocity, and that will inevitably lead to injuries. Perhaps that’s the next inefficiency small teams will exploit. We’ve seen different fastball varieties like the cutter and sinker fall out of fashion over the past decade, but players like José Quintana and Corbin Burnes have thrived off those pitches.
If teams are more willing to gamble on a young pitcher who specializes in those or other lower-strain pitches, we could see fewer velocity-related injuries. For now, though, fans are waiting for the day their favorite pitcher hits the shelf.