May 16, 2014
The Injury Puzzle
In a season that has been beset by pitcher injuries, the loss of the game's most electrifying ace, Jose Fernandez, was the straw that broke the collective heart of the baseball universe. How did it come to this?
One of the missions of Raising Aces is to explain the why and the how behind pitcher performance. There are known reasons why a pitcher might be missing his spots, and we understand how he creates movement on his pitches. Unfortunately, we’re far from identifying concrete truths about why and how a given pitcher gets seriously injured.
By day I’m a mild-mannered educator, and right now we’re knee-deep in finals preparation. One of the most useful strategies that I employ with the students is “to know what you don't know.” The method requires an honest analysis of one's strengths and weaknesses, with the goal of isolating potential problem areas in order to optimize the learning process. When we bring this method to bear on the baseball world, it’s important that we appreciate and accept the current state of injury evaluation, in which there are far more questions than answers.
It's human nature to attempt to isolate a singular cause when something goes wrong, but science rarely affords us the convenience of simplicity, and the profile of a professional pitcher is riddled with intertwined risk factors that can conspire to take him off the mound. The analytical community is still trying to understand these elements on an individual basis, and the issue is further complicated by the chain-linked nature of the variables at play. Very rarely is the explanation obvious, and mechanics are just part of the picture.
Let's take a look at some of the pieces in the injury puzzle of a big-league pitcher.
What we know about Fernandez: The Marlins have been very careful with their wunderkind’s workload. He has exceeded 110 pitches in a game just once in his career, and this season he had cleared the century mark in just three of his eight outings. His 3985 Pitcher Abuse Points (PAP) ranks a modest 34th among pitchers this season, yet he has already accumulated more PAP than he did in all of 2013, a year in which he totaled just 1640 total PAP in 28 starts (ranked 145th).
The specific mechanical alterations also vary from player to player, often having an impact on positioning, timing, stability, and/or power. The key for each organization is the ability to recognize fatigue within each of their pitchers and to understand the risks when one starts to lose it. The onset of fatigue can follow very different patterns for each pitcher, which supports the use of more dynamic pitch-count thresholds that are tailored to each arm’s fatigue conditions. In the not-so-distant future, teams could have access to in-game data that compares present performance to mechanical baselines, allowing for an objective indicator of fatigue and taking much of the guesswork out of the equation.
What we know about Fernandez: He rarely displayed obvious signs of fatigue. The careful workloads likely contributed to his consistency, both in-game and between outings, and on most days Fernandez was able to maintain velocity from the first pitch to his last. His ability to hold velocity was not quite as strong in early 2014 as it had been last season, and in his final start the velocity took a sudden nosedive after he hit the 50-pitch mark, at a time when he was visibly laboring to execute his pitches.
There are also injury concerns tied to nearly every type of secondary pitch, with entire organizations disdaining the cutter or distrusting the splitter. Breaking pitches get the most publicity in this arena, as curveballs and sliders that require a large degree of pre-set supination can be tougher on the arm, given that the amount of pronation that takes place after release point is naturally greater. Supination is one method of throwing breakers, but the alternative is even more dangerous: a late twist of the wrist near release point that compounds the injury risk during the most intense phases of the delivery. Many coaches will limit breaking-ball frequency as part of their plan for workload management, since throwing 60 fastballs and 40 curves is more taxing than an 80/20 split.
What we know about Fernandez: He throws really, really hard. His average fastball velocity of 96.6 mph ranked as the fifth-highest mark in baseball this year (minimum 200 fastballs). His breaking ball is one of the nastiest pitches in the game, but he requires a great degree of supination in order to generate the ludicrous movement on the pitch, and his use of the Defector had grown to worrisome levels. Fernandez threw the pitch 33.8 percent of the time in 2013, and that rate rose to 37.2 percent this season. He began to utilize his changeup more often over his final three games, but he threw as many as 54 Defectors (out of 109 pitches) in a single game this season, and he has thrown the second-most curves in baseball in 2014.
The mechanical report cards that I put out for each pitcher are based on biomechanical efficiency and functional utility, but there exist some double-edged swords that effectively blur the line between function and safety. For example, efficient mechanics can help a pitcher throw harder, but the resulting increase of kinetic energy through the system elevates the overall risk of breakdown. To truly understand a pitcher's physical injury risk, we have to acknowledge the connecting links in the chain that have a direct influence on his mechanical efficiency and personal signature. Workloads, fatigue, conditioning, and genetics will all influence the delivery, and mechanical inconsistency has the potential to accelerate injury.
What we know about Fernandez: Fernandez has some of the best mechanics in the game. His report card is remarkable, with plus grades in every category and an overall score that is almost unfathomable for a pitcher his age. He has a blend of stability, power, and consistency that fuels his incredible stuff and stellar command. In 2014, the balance and posture had been slightly behind last year's peak, and he had altered his stride direction to finish a bit more closed off, but such trends are common early in the season, and the overall package was still one of the best in baseball.
Mechanics Report Card
What we know about Fernandez: He has a great reputation as a hard worker who is dedicated to his craft, but there is very little information available to the public that would help us properly assess his training methods. The Marlins have a much better idea of how Fernandez’s physical preparation is supporting his development.
What we know about Fernandez: We know next to nothing about his genetics, beyond the visible evidence of a prototypical pitcher's build at 6'2” and 225 pounds.
It’s tempting to look for causation when we suffer a loss like that of Fernandez, and the UCL epidemic of 2014 has put injuries at center stage, but we need time to put some distance between logic and emotion in order to gain a reliable perspective. We could look back at this season as a blip on the radar, or it could turn out to be a turning point in the understanding of pitcher injuries, but the possibility of the latter scenario rests on the recognition of the former. Baseball will miss the exhilarating talent of Fernandez for the next 12-18 months, but rather than over-analyze his scenario in an attempt to find the smoking gun, we can take a step back and reconsider our approach to the mystery of injury prevention by appreciating the interconnected nature of the risk factors involved.
In the meantime, we still have 36 Fernandez starts in the MLB.TV archives to sustain us.