New Year’s Holiday Sale: ends december 31st
There is a particular kind of study that arrives wrapped in good news, and if you are not careful, you accept the gift without ever inspecting the box. A 2026 study in The Orthopaedic Journal of Sports Medicine is exactly that kind of study. The headline practically writes itself: after the MLB pitch clock arrived, pitcher injuries went down. Injury rates dropped from 50.4% before the clock to 39.3% after, time to first injury got longer, and the authors concluded there was no significant rise in elbow injuries. If you stopped reading at the abstract, you would walk away believing the clock made pitching safer. But the most important decisions in this study were made before a single injury was counted, and once you see them, the good news starts to look a lot more like a magic trick.
Lavi and colleagues analyzed 800 high-volume pitcher-seasons spanning 2021 through 2024, comparing the two seasons before the pitch clock to the two seasons after. On the surface, the numbers are clean. The proportion of injured pitchers fell from just over half to just under 40%, a statistically significant drop. The average time before a pitcher's first injury stretched from roughly 143 days to 161 days. A survival model estimated that pitchers in the post-clock era were about 31% less likely to get hurt. Batters faced climbed from 525 to 575 per season, yet total pitches and pitches per inning stayed flat, which the authors read as evidence that the clock sped the game up without piling on workload. It is a tidy, reassuring story, and that is precisely what should make you suspicious.
Here is the decision that quietly governs everything. The study did not look at all pitchers. Each season, it included only the 200 highest-volume pitchers by total pitch count. Think carefully about what that sentence actually does. To make the list, a pitcher has to throw a lot of pitches, which means he has to stay healthy enough to keep taking the mound deep into the season. So who never makes the list? The pitcher whose elbow blows out in April. The reliever who tears his UCL in the first month and disappears. The arm that breaks early and catastrophically, which is to say, the exact injuries we care about most. To be honest, this reminds me of surveying the survivors of a shipwreck about how safe the voyage was. The people best positioned to tell you the trip was dangerous are at the bottom of the ocean, and they are not filling out your questionnaire.
The authors, to their credit, admit this in the limitations. They acknowledge that their approach excludes pitchers who got hurt early or severely and therefore could not accumulate enough pitches, and they concede their findings may underestimate the true incidence of high-impact injuries like UCL tears. That is a remarkable thing to print in a study whose headline is that injuries went down. They told you the box might be empty, in small type, after handing you the gift.
Then there is 2024. If you trace the elbow and forearm injuries year by year, you see 25 in 2021, then 17, then 16, and then a jump to 27 in 2024, the highest count of the entire study window. The category they labeled "other elbow," which includes inflammation, followed the same arc and rose from 9 in 2022 to 23 in 2024, a change that was statistically significant. Yet the conclusion leans on the decline through 2022 and 2023 and treats the 2024 spike as noise, in part because the elbow-specific rise did not clear their significance threshold. Maybe it did not. But when the most feared injury in the sport quietly climbs to a four-year high in the final season of your data, that is the headline you investigate, not the footnote you wave away.
The survivorship problem is not a hypothetical. We have known for years where these injuries cluster in time. DeFroda and colleagues, back in 2016 and in this same journal, found that 62% of MLB UCL tears occur in the first three months of the season, with nearly a quarter happening within a pitcher's first 100 innings and disproportionately among relievers. Sit with that. The majority of catastrophic elbow injuries land early, in lower-volume arms, which is the precise population a top-200-by-pitch-count filter is built to exclude. A study designed this way is not measuring whether the clock is dangerous. It is measuring how the durable survivors fared, and then quietly letting that stand in for everyone.
The second problem is the variable that never appears. This study did not measure or control for pitch velocity, and velocity is not a minor detail in elbow injury. It is the detail. Mastroianni and colleagues, again in this same journal in 2025, found that velocity was the single strongest predictor of UCL surgery, with every 1 mph increase raising the odds of surgery by nearly 20%. Barrack and colleagues showed the mechanism underneath it, where each 2.2 mph of velocity adds measurable torque to the elbow. We are living through an era where average fastball velocity has been marching upward for more than a decade. If the arms in this dataset were throwing even a tick harder in 2024 than in 2021, the cumulative stress on the ligament rose even if the pitch counts looked identical. Leaving velocity out of an elbow injury study is like studying lung cancer and declining to ask who smoked.
And here is the part that should bother anyone treating this as settled. The literature does not actually agree with the reassuring headline. Ashy and colleagues, in a 2026 Arthroscopy study, took a different and frankly more honest population, every pitcher with at least 70 pitches in both seasons rather than only the busiest 200, and found the opposite. A faster pitch pace was associated with more injury, where each one second reduction in time between pitches raised injury odds by 19%, and starting pitchers carried 120% higher injury odds plus nearly triple the rate of UCL surgery compared to relievers. Same rule change, nearly opposite conclusion, and the difference comes largely down to who you let into the study. Even Card and colleagues, whose 2025 paper leaned sympathetic to the clock and framed it as possibly protective, did not find that injuries went down. They found UCL tear incidence essentially unchanged between eras, 0.63 versus 0.67 per 1000 innings, while pitchers absorbed 61% more pitches before getting hurt. And notably, Card's study only counted surgically treated UCL tears with a public paper trail, carrying its own version of the same blind spot. So the cleanest reading across these studies is not that the clock made pitching safer. It is that the clock pushed pitchers to do more, and that the question of what that costs depends enormously on who you bother to look at.
The practical skill here has almost nothing to do with the pitch clock and everything to do with how you read a study before you let it change your mind. The first question is always who got excluded, because the inclusion criteria often decide the conclusion before any analysis runs. When a study keeps only the most durable arms, its findings apply only to durable arms, full stop. The second question is what went unmeasured, because the variable a study leaves out is frequently the variable that explains the result. Here, velocity was the ghost in the room. The third question is whether the framing matches the raw numbers, because a four-year high in elbow injuries does not become reassuring just because it sits below a significance cutoff in a study that already excluded the most injured pitchers.
For coaches, clinicians, and parents trying to make real decisions, the takeaway is to keep treating rising velocity and accumulating workload as the live risks we already know them to be, regardless of a comforting headline about a rule change. A reduction in time between pitches gives the arm less recovery, and whether that shows up in a given dataset depends entirely on whether that dataset can see the arms that broke. Do not let a study that filtered out the casualties talk you out of caution. And if you take nothing else from this, take the habit of reading the limitations section first. It is where the authors tell you, in the quietest possible voice, what their headline cannot actually support.
I am not going to pretend to know what was in the authors' minds, and I do not need to. The structure of the study does the persuading on its own. When you build a sample that systematically removes the pitchers most likely to be catastrophically injured, decline to measure the one variable most tied to elbow injury, and then dismiss a four-year high in elbow injuries as you lead with a story about declining injury rates, the design itself tilts toward a reassuring answer. That is not a knock on anyone's integrity so much as a warning about how easy it is for a methodology to walk you toward the conclusion it was shaped to reach. The pitch clock may turn out to be fine. It may turn out to be a real problem, especially for older starters absorbing more batters per outing. We genuinely do not know yet, and a study that decided who counted as injured before it started counting is not going to be the one that tells us. So the next time a headline hands you good news in a tidy box, do the one thing this study is counting on you not to do. Open it.
Lavi A, Johnson M, Ibrahim T, et al. Pitch Counts and Injury Incidence in Major League Baseball: Responses to Pitch Clocks and Defender Rule Changes. The Orthopaedic Journal of Sports Medicine. 2026;14(1).
Ashy CC, Baird HBG, Gannon S, Myer GD, Pullen WM, Slone HS. Older, Starting, and Pitchers With Greater Increase in Pitch Pace Experience Elevated Injury Risk Following Pitch Clock Implementation. Arthroscopy. 2026.
Card RK, Liakos BJ, Schwartz JT, et al. Pitch Clock Increases Tolerated Workload Before Ulnar Collateral Ligament Injury: A Retrospective Cohort Study of Major League Baseball. The Orthopaedic Journal of Sports Medicine. 2025;13(9).
DeFroda SF, Kriz PK, Hall AM, Zurakowski D, Fadale PD. Risk Stratification for Ulnar Collateral Ligament Injury in Major League Baseball Players: A Retrospective Study From 2007 to 2014. The Orthopaedic Journal of Sports Medicine. 2016;4(2).
Mastroianni MA, Kunes JA, El-Najjar DB, et al. Advanced Analytic and Pitch-Tracking Metrics Associated with UCL Surgery in Major League Baseball Pitchers: A Case-Control Study. The Orthopaedic Journal of Sports Medicine. 2025.
Barrack AJ, Sakurai M, Wee CP, et al. Investigating the Influence of Modifiable Physical Measures on the Elbow Varus Torque – Ball Velocity Relationship in Collegiate Baseball Pitchers. The Orthopaedic Journal of Sports Medicine. 2024;12(11).
