Stephen Strasburg's innings limit is not rooted in science, but Nationals believe it's prudent

What the Washington Nationals are doing with Stephen Strasburg isn't stupid. It's just not smart, either.

Shutting down Strasburg for the remainder of the season, as the Nationals plan on doing sometime within

the next month, is a decision based neither in science nor logic. It's a guess. That is all. The Nationals are guessing it is good to limit Strasburg's sewn-together elbow to somewhere in the 160- to 180-inning range in his first full season post-Tommy John surgery.

They are guessing because the hard, study-backed evidence to say whether that's actually the case does not exist, and because when it comes to the pitching arm, there is no such thing as logic. The arm is the most fickle thing in sports. It takes an unnatural motion, replicates it a hundred times a game, thousands of times a year, wearing down the elbow and shoulder until one gives. Except, of course, for the pitchers with great mechanics and genetics and work habits and luck whose arms somehow survive the grind and avoid a breakdown.

Those are the outliers. Strasburg, 24, is more the rule, in getting hurt and babied. That is what injuries have wrought: million-dollar bonus babies limited to three-inning stints, teams afraid to push young pitchers more than 30 innings beyond what they threw the previous season and a culture of fear in which general managers and managers don't want to be the one on who's watch a prized elbow, like Strasburg's, blows for a second time.

"We feel that we do know this is going to work," Nationals general manager Mike Rizzo said. "We've done research. We feel like there's evidence. We're not saying we're smarter than anyone else. But we're going to do it the way I want to because I'm in charge. That's the answer I have to all the critics and all the ex-players. They're welcome to it. They're very astute. But the majority didn't make their bones in player development."

Rizzo did, as a scout, a scouting director and now the GM of the team with the best record in baseball. He is making a choice criticized far and wide, one for which other executives laud him because it takes the sort of conviction rarely seen in a decision of such magnitude.

And if we're really going to have an honest, frank and fair look at that decision, perhaps it's best first to look at what we do know.

Baseball is on pace to lose more than $500 million in salaries and replacement costs to the disabled list this year, a new record. Despite the staggering advances in medicine over even the last decade, more players get injured today than ever. And the majority of DL time comes from the smaller portion of the baseball population: pitchers.

Look at the DL right now. There are 52 starting pitchers. That's more than 10 full rotations. Another 62 relievers join them. Almost half of the pitching population in baseball will spend time on the disabled list in any given season. Injuries are especially endemic among 18- to 25-year-olds.

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Conversations with trainers, orthopedists and biomechanists – those at the front line of trying not just to fix injuries but learn how to prevent them – paint a picture so ugly it's understandable the Nationals want to err on the side of caution with the game's most dynamic young arm. Catastrophic injuries tend to hit the 25-and-under population with greater frequency than their wizened counterparts. The 25-and-younger group represents 28.5 percent of the 592 pitchers who have thrown in the major leagues this season. Of the 29 Tommy John surgeries this year, 12 – or 41.4 percent – have been on pitchers between 21 and 25.

The scourge victimized Strasburg in August 2010, his breakout rookie season in which he toasted hitters with 102-mph fastballs, froze them with unfair curveballs and threw in a vicious changeup for maximum insult. He was a pitching cyborg, sent from the future to remind everyone what the human arm could do.

Then, to remind us he was indeed human, he broke. Pitchers' elbows are not widgets. They're not built according to a code, each the same. One thing nobody can account for is the physiological differences in every pitcher. Their musculature. Their joints' strength. Their arm actions. Biomechanists have seen pitchers whose motions look awful to the naked eye, only to test out efficiently and with minimal excess force on the elbow and shoulder. And there are those whose deliveries appeal to the aesthete only to fold under the weight of their body's frailties.

It is imperative to remember the elbow, in particular, is not built for throwing. It is a hinge, constructed to flex and extend, to bend up and down, in and out. The ulnar collateral ligament – better known as the Tommy John ligament – is built as a stabilizer. For pitchers, it serves as a stress regulator. Every pitch puts an immense amount of torque on the UCL. Some elbows hold up. More cannot.

The fear comes from the unknown. Executives want to ascribe injuries to something more than bad luck, and overuse is the easiest culprit. Pitch counts arrived in full force around the mid-1990s, and in less than a decade the tickers in every stadium grew into an ever-present watchdog on managers. Anger the pitch-count gods and the wrath of Tommy John will strike down on thee.

"And what have pitch counts done?" one trainer asked. "What is the reason you do pitch counts? To protect the pitcher's arm. The DL will tell you it has not protected the pitcher's arm."

His point: It's not science, not yet, not as long as a study or a hypothesis that has been replicated outside of a laboratory continues to elude those in charge of the game. For every idea that seems to have merit – Sports Illustrated writer Tom Verducci, for example, claims that young pitchers who increase their inning load by more than 30 become an injury risk – there is a perfectly reasonable argument against it. In Verducci's case, it's this: Of course young pitchers run a risk of getting injured. They're young pitchers. Their injury rate is already 50 percent. Correlation is not causation.

The most fascinating part of the Nationals plan to shut down Strasburg is that in spite of not knowing, they don't care, either. The Nationals are potentially jeopardizing their fantastic 2012 season to do something that they have absolutely no idea will protect his arm from further damage. Rizzo has cited advice from medical experts, but in reality he's hearing what's convenient for him to hear, unless the Nationals know something the rest of the baseball world doesn't.

"I guess it's a gutty move, a ballsy move," he said. "I'm a stubborn guy. I'm going to do this thing the way I want to do it. The plan since I took over three years ago has worked well for us. I have the trust of ownership that we're going to do this the right way. We believe we're right in this instance. We're going to implement it. That's not to say the industry's going to understand it or our right-handed starter is going to understand it. But what it does show is that we have a long-term vision, and I think it's going to show that we care about our players and we're going to do what's best for them personally.

"We have pages and pages of evidence backing this. We have volumes of testimonies of doctors. We've got research and test cases and histories on guys. It's a small sample. This is a very unique pitcher. Tommy John surgeries before the age of 23 years old on power pitchers that average 95 mph on their fastball and 91 mph on their changeup – there's not a lot of those guys around."

Still, Washington saw such great progress from its first big Tommy John case, Jordan Zimmermann, that it's dead-set on emulating his return almost to the inning. Like Strasburg, his surgery was in August (of 2009). Like Strasburg, he returned for the end of the following season (and threw 31 innings, to Strasburg's 24). And how many innings did Zimmermann throw in his first full season back? 161 1/3.

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Today, Zimmermann is one of the NL's best pitchers, with a 2.35 ERA in 145 1/3 innings. If he makes 34 starts and maintains his per-outing average, he'll throw nearly 215 innings. He is a great success story. Even if he is a sample size of one, and even if his delivery is entirely different than Strasburg's, and even if his body isn't nearly the same, and even if every pitcher is like a fingerprint, Zimmermann is the archetype to which the Nationals are hitching their future.

"They have a theory. They have a belief. Theirs is no more right or wrong," the trainer said. "But they're willing to take that theory off the blackboard and put it into practice. That takes a lot of guts. That takes a lot of belief that they're doing the right thing. That's a very hard thing in baseball to do: go against the grain. For me, that's kind of exciting to watch.

"I'm not so sure I'd stand in front of that truck."

We'll never know if the Nats were right or wrong. Should Stephen Strasburg stay healthy for the next decade – doctors believe the lifespan on a new UCL is somewhere between 8-10 years – the Nationals will claim they handled him right. And maybe they'll have done so. Maybe their hypothesis – limit innings in the first full post-Tommy John season – has merit.

It may have merit, in fact, even if Strasburg blows out again within a couple years. Everyone who works with the arm learns a harrowing lesson again and again: Just when you think you know something, you don't. For every Joel Zumaya, whose arm couldn't hold up under 104 mph of stress, there is a Justin Verlander, whose arm grows stronger the more he pitches. For every Jordan Zimmermann, whose 160-inning plan has worked, there is going to be someone for whom it doesn't.

The closest thing to proof about the efficacy of innings limits is among teenagers. Studies have shown pitchers who throw more innings are likelier to blow out their elbow or shoulder. There is no specific number of innings. It's simply a caution to limit the workload on young arms – which, biomechanists admit, are entirely different beasts from strong, developed adult limbs.

Washington's intentions here are laudable. Strasburg isn't a free agent until 2017. With him, Zimmermann and Gio Gonzalez, the Nationals' rotation should be great for years. So goes their caution: There's no sense in taking a chance of ruining that by overextending him, even if Strasburg wants to keep pitching, which he has said he does.

"We're going to build our rotation around Stephen Strasburg," Rizzo said. "I want him to be around a long time after 2012."

It would be nice to have injury databases that allowed trainers and doctors to look back at the thousands of other pitchers who got hurt, track how long it took them to recover, and annotate their pitfalls, successes and otherwise. The players' union doesn't exactly like the idea of MLB using this sort of data to potentially discriminate against certain players whose injuries would raise red flags, so such databases don't exist nearly to the level they should.

Which leaves Washington guessing, and potentially risking the city's first World Series appearance since 1933. It's not stupid. It's not smart. It's the product of fear borne of uncertainty and the arm's inherent fragility. Tonight, when Strasburg makes his 23rd start of the season against the Arizona Diamondbacks, he will do what he has done in the previous 219 1/3 innings of his career (including 127 1/3 innings this season): put massive amounts of stress on his elbow and shoulder and hope both cooperate.

It will be that way, in fact, for the rest of his career, a tug-of-war between the arm and nature, the ugliest relationship in sports, one Stephen Strasburg knows all too well.

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