Questions about Stephen Strasburg's delivery have no sure answers

Stephen Strasburg's motion is the subject of more conversation after a Sports Illustrated article that relied on the findings of biomechanist Glenn Fleisig. (Jonathan Newton/The Washington Post)
Stephen Strasburg's motion is the subject of more conversation after a Sports Illustrated article that relied on the findings of biomechanist Glenn Fleisig. (Jonathan Newton/The Washington Post)
Washington Post Staff Writer
Thursday, March 10, 2011; 12:08 AM

JUPITER, FLA. - On Wednesday morning in Viera, Fla., Stephen Strasburg played catch with a Washington Nationals trainer in the outfield of Space Coast Stadium. He focused only on his next throw, one careful toss after the next, the monotonous churn that will eventually return him to a major league pitching mound. Strasburg paid no attention to the lingering questions about what happens when he does.

Those questions - about what went wrong last year and what kind of pitcher he will be following his recovery from Tommy John surgery - drew new attention Tuesday after Sports Illustrated published on its Web site an article detailing a specific mechanical movement that, the piece asserted, led to Strasburg tearing the ulnar collateral ligament in his right elbow. Nationals officials have said they will not change Strasburg's mechanics upon his return. The SI story relies on the findings of biomechanist Glenn Fleisig, Ph.D., to suggest they should.

Despite Fleisig's definitive assertion, there are no consensus answers. Other experts have watched Strasburg's mechanics and found no reason for concern. The Nationals believe Strasburg's ligament tore because of a single pitch, not the accumulation of wear. Fleisig may very well be correct that Strasburg's mechanics ensured his elbow ligament would tear.

But there is no certain answer to why Stephen Strasburg broke.

"I'm not sure that there's a universal, 100-percent thought that, 'This is the reason,' " said Cincinnati Reds team doctor Tim Kremchek, who performs more than 100 ligament-replacement surgeries per year. "I think that's impossible. I think that there are good theories. Who's to say it's not true? I think that's okay. But you got to be real careful. I'm not going to say it's right or wrong. I'm going to say it's dangerous to hang your hat on one thing."

In the Sports Illustrated piece, written by Tom Verducci, Fleisig outlines the problems with Strasburg's motion. A pitcher's foot should land precisely when his arm reaches maximum external rotation, which occurs when a pitcher cocks his arm to throw, that split second that divides wind-up from release.

When Strasburg removes the ball from his glove, he leads by yanking his elbow backward rather than swinging the ball downward. That maneuver delays Strasburg's arm action during his delivery and leads to what Verducci's piece describes as the crucial flaw. Strasburg finishes cocking his arm only after his front foot lands, timing that places a hazardous amount of force on the shoulder and elbow.

Verducci also cited an unnamed team official who refuses to draft or otherwise acquire pitchers whose mechanics include the glitch.

The concern is legitimate, but not unanimous. Last year, Dick Mills, a former major league pitcher who produces movies and books on pitching mechanics, reviewed film of Strasburg with two kinesiologists and two biomechanists who were not previously familiar with Strasburg. They studied his delivery, with special attention on his shoulder abduction, the position of a pitcher's arm when he pulls it away from his body. All four sports scientists told Mills not to worry.

The Nationals are firm on one point: They see no reason to change Strasburg's mechanics. Kremchek, the doctor who has performed hundreds of Tommy John surgeries, agrees with that decision.

"You're taking a guy that's been throwing this way for a long time," Kremchek said. "You're not sure what changing those mechanics is going to do. You just don't know. I think that's a dangerous thing to do."

The Nationals could change Strasburg's style of pitching, having him aim for fewer strikeouts and more groundballs early in the count. General Manager Mike Rizzo, who declined comment for this story because he had not yet read the SI story, told Verducci that Strasburg might throw more two-seam fastballs that hover around 95 miles per hour rather than lighting up radar guns with triple digits.

Even that could create complications. For one, "two-seamers probably put more stress on your arm than a four-seam fastball," Manager Jim Riggleman said.

And asking for more groundballs from Strasburg would push against a trend predicated on one of baseball's most groundbreaking recent theories: the notion that a pitcher has little control over what happens once the ball is put into play. Many teams evaluate pitchers more than ever on what has come to be called Defense Independent Pitching Statistics, DIPS for short. The most important thing a pitcher can do, per this theory, is strike out a lot of hitters and walk few.

"Do you take something away from his ability to pitch?" Riggleman asked. "And guys get hurt when they change their deliveries, too. . . .

"Young power pitchers, you always worry about them," Riggleman added. "I was worried about [Strasburg] before he got hurt. I was worried about Kerry Wood. The only way to make sure they don't get hurt is don't pitch them."

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