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----------------------------------------------------------------------------------------------- 916.  Another NY Times Article on Pitching Injuries

Now Glenn Fleisig is saying that the traditional supination curve ball is OK for young kids, although Dr. Andrews does not agree with the results.


Studies Show that the Curveball Isn't Too Stressful for Young Arms
July 26, 2009

For almost as long as children have been throwing baseballs, adults have been telling them about the worst thing they could do to their still-developing arms: throw curves.

The warnings go back to the earliest days of sports medicine, orthopedic surgeons say, at least to the 1950s.  In the 1970s, Robert Kerlan, the eminent surgeon who cared for Sandy Koufax, condemned curveballs as murderous on the elbows of professional pitchers, “to say nothing of the young athletes whose bones and joints are still growing.”

That remains the mantra of many sports medicine experts.  The orthopedic surgeon James Andrews, who performs more than 100 Tommy John ligament-transplant operations most years, cautions that children should not even think about throwing curves until they are 14.

Are those doctors all alarmists?

Maybe so, according to two studies in which scientists and surgeons evaluated more closely than before the effects of curves on young arms.

The studies were done independently by research teams in Connecticut and in Alabama.  Each compared the forces across the elbows of pitchers as they fired fastballs and curves.  (The Alabama study also included changeups).

Each study concluded that curves are less stressful than fastballs and, based on the data collected, contributed little, if at all, to throwing injuries in youth players.

“I don’t think throwing curveballs at any age is the factor that is going to lead to an injury,” said Glenn Fleisig, the chairman of research at the American Sports Medicine Institute in Birmingham, Ala.

Carl Nissen, the principal author of the other curveball study and an orthopedic surgeon at the Connecticut Children’s Medical Center in Farmington, echoed that.  “I can comfortably stand up and say the curveball is not the problem,” he said.

The curveball research has not ended the debate.  If anything, it seems to have intensified it.  One of the reasons is that the findings come from reputable sources and in particular from the A.S.M.I., whose president and founder is Andrews.

Over the years, the institute has produced research studies on all manner of sports movement, from biomechanical comparison of female and male baseball pitchers to an analysis of the swings of professional and amateur golfers.

In 2006, Fleisig and Andrews published a study on the effects of curveballs on college pitchers: curves were less stressful on the elbow than fastballs.

Intrigued, the research team repeated the study using youth pitchers as their subjects.  They posted notices on youth baseball Web sites seeking players in the Birmingham area for a curveball study. Even that proved somewhat controversial.

“We had a few complaints from coaches saying, ‘How dare A.S.M.I. promote and endorse the curveball,’ ” Fleisig said.

In all, the institute’s study looked at 29 youth pitchers from ages 9 to 14.  All were told to throw their curves — fastballs and changeups, too — as if they were in a real game.  The results, published last year in the American Journal of Sports Medicine — Nissen’s study has been accepted for publication in the same journal — were similar to those that Fleisig had found with the college pitchers:  Curves were less stressful than fastballs; nothing linked curves to elbow injuries.

Why for so many decades have most doctors and youth coaches believed otherwise?  Fleisig said the evidence had been based largely on anecdotes, and that over the years those stories simply began to sound like fact.

“Why did people believe the world was flat?  Because one guy told another it was flat and it looked flat.  Until someone discovered that it wasn’t,” he said.

The new research has put some sports medicine experts in an awkward spot.  Topping the list is Andrews, a surgeon sought out by dozens of injured professional athletes each year.

In July, Andrews became the president of the American Orthopaedic Society for Sports Medicine, a position in which he is championing a national campaign to curb sports injuries in children.  Andrews does not challenge A.S.M.I.’s study.  But he is hardly trumpeting the findings.

“It may do more harm than good — quote me on that,” Andrews said during an interview in his Birmingham clinic.  He fears that parents and coaches may interpret the findings improperly, as a license to teach kids to throw too many curves or begin when they are too young.  “There are still some unknown questions,” he said.

Andrews cited several limitations of the study.  The fact that it was conducted entirely in a lab also needed to be considered, he said.  Under game conditions when youth pitchers are fatigued, Andrews suggested, curves could be dangerous.

“I just operated on one kid this morning,” he said.  “At age 12, he tore his ulnar collateral ligament in two.  His travel ball coach called 30-something curveballs in a row.  He became fatigued.  Then he threw one that snapped his elbow.”

Despite differences over curves, experts do agree on other risks to young pitchers.  At the top of the list are unreasonably long seasons and pitchers throwing too many innings in individual games.

One study of youth pitchers written by Fleisig and Andrews found youth players who pitched more than eight months a year increased their risk of an injury that led to surgery fivefold.  Youth players who threw more than 80 pitches a game were four times more likely to need an arm operation than those who did not, according to the study.

“I’m not saying, everyone throw the curveball,” Fleisig said.  “I’m saying, if we’re going to prevent injuries, change the focus.  We should be looking at overuse.”

Mark Hyman is the author of “Until It Hurts: America’s Obsession With Youth Sports and How It Harms Our Kids.”


     This article shows why biomechanical analysis of baseball pitching does not identify the causes of baseball pitching injuries.  Biomechanical analysis only provides tables of numbers.

     In these studies, the researchers found that the numbers for the stress on the pitching elbow for throwing curves are not at high as the numbers for the stress on the pitching elbow for throwing fastballs.  Therefore, the Biomechanists concluded that throwing curves is less stressful than throwing fastballs.

     However, everybody knows that, when baseball pitchers of all ages throw the 'traditional' curve, they destroy their pitching elbow.  Dr. Andrews noted that he recently performed Ulnar Collateral Ligament Replacement surgery on a youth baseball pitchers that ruptured his Ulnar Collateral Ligament immediately after he threw thirty plus consecutive curves.

     When Biomechanist Glenn Fleisig said, “I don’t think throwing curveballs at any age is the factor that is going to lead to an injury,” and Biomechanist Carl Nissen said, “I can comfortably stand up and say the curveball is not the problem,” they showed that they only look at numbers in their biomechanical table.

     If they understood what happens differently when baseball pitchers of all ages throw the 'traditional' curve, then they would have known better than to make these statements.

     There are two injurious mechanical flaws in their baseball pitching motion that that make throwing 'traditional' curves a very dangerous pitch.

01.  I call the first injurious mechanical flaw, 'Looping.'

     When baseball pitchers throw the 'traditional' curve, they use their pitching forearm differently than when they throw fastballs.

     When baseball pitchers throw fastballs, at release, they have the anterior surface of their pitching hand, wrist and forearm facing toward home plate.

     When baseball pitchers throw the 'traditional' curve, they have the little finger side of their pitching hand, wrist and forearm facing toward home plate.

     This means that when baseball pitchers throw 'traditional' curves, they rotate their pitching hand, wrist and forearm ninety degrees farther than when they throw fastballs.  Therefore, when they throw 'traditional' curves, they make a circle with their pitching forearm.  This is the action that I call this, 'Looping.'

     Some 'traditional' baseball pitchers 'loop' when they throw fastballs and those baseball pitchers also suffer Ulnar Collateral Ligament ruptures.  But, all baseball pitchers 'loop' when they throw 'traditional' curves.

     When Tony Saunders broke his pitching upper arm, he was throwing the 'traditional' curve.  This looping action places considerably more stress on the Humerus bone of the pitching upper arm.  These Biomechanists simply do not know how to collect reliable data.

02.  I call the second injurious mechanical flaw, 'Pitching Forearm Flyout' coupled with 'Supinating the Release.'

     All 'traditional' baseball pitchers have 'Pitching Forearm Flyout.'  'Pitching Forearm Flyout' happens when baseball pitchers take their pitching arm laterally behind their body.  That is, right-handed pitchers take their pitching arm laterally behind their body toward first base.

     When 'traditional' baseball pitchers take their pitching arm laterally behind their body, before they can throw their pitches toward home plate, they have to return the baseball to the pitching arm side of their body.

     This means that they have to apply force to their pitches toward the pitching arm side of their body.  When they do this, they create a horizontal centripetal force that slings their pitching forearm laterally away from their body.  That is, right-handed pitchers sling their pitching arm toward third base.

     The result of this action is two-fold:

01.  The bones on the back of their pitching elbow slam together, which causes baseball pitchers to decrease the extension range of motion in their pitching elbow and

02.  To prevent these bones from slamming together, they contract the Brachialis muscle on the front of their pitching upper arm, which enlarges the coronoid process to which it attaches and they decrease the flexion range of motion of their pitching elbow.

     But, these injuries also result from 'traditional' baseball pitchers throwing fastballs.

     However, when 'traditional' baseball pitchers combine their 'Pitching Forearm Flyout' with 'Supinating the Release' of their 'traditional' curve, the result is very dangerous.

     Supination means that baseball pitchers turn their pitching thumb away from the little finger side of their pitching forearm, such that the thumb faces upward.  As a result, they release their curve over top of their index finger.  When asked how to throw curves, all 'traditional' baseball pitchers will demonstrate the same dangerous technique.

     When baseball pitchers combine 'Pitching Forearm Flyout' with 'Supinating the Release' of their curve, they greatly increase the likelihood that they will slam the bones on the back of their pitching elbow together.

     At the very least, they will injure the hyaline cartilage that lines the olecranon fossa, which will calcify and make the fossa less deep.  But, when the olecranon process repeatedly slams into its fossa, baseball pitchers can also break the olecranon process off the end of the Ulna bone of the pitching forearm.

     Unfortunately, Biomechanists Fleisig and Nissen know just enough to make the dangerous and not enough to know what they are talking about.  When we encounter people who think that they know something, but they do not, we have to ignore everything that they say.  These guys have no idea what they are talking about.


     In Q#234 of my 2011 Question/Answer file, I included an article written by Tom Verducci published on sportsillustrated.cnn.com about Stephen Strasburg.

     In the following segment, Mr. Verducci talks about Dr. Fleisig's finding that throwing curveballs does not stress the pitching arm more than throwing fastballs.

Mechanical flaw will be red flag for Strasburg even after return

     Mr. Verducci wrote:

Strasburg also relied on his curveball often.  He threw the 11th highest percentage of curveballs among pitchers who pitched at least 60 innings (25.5 percent).  But trying to link his injury to curveballs is rooted in myth that is not supported by vast medical research.  The curveball, despite long-held speculation, is not more stressful on the arm than high-velocity fastballs.  A 2009 study of college pitchers found no difference in elbow and shoulder loads between curveballs and fastballs, and studies in 2008 and in 2009 of youth pitchers found greater joint loads associated with fastballs rather than curveballs.


     In response, I wrote:

     This is Dr. Glenn Fleisig's research.  As always, Dr. Fleisig does not understand the rest of the story.

     I agree that, whether baseball pitchers throw pronation-released fastballs or supination-released curves, the elbow and shoulder loads that they generate are insignificantly different.

     The point that it appears everybody does not understand is that the injuries that baseball pitchers suffer as a result of throwing supination-released curves has nothing to do with elbow and shoulder loads.

     Instead, the injury that baseball pitchers suffer as a result of throwing supination-release curves is that they bang the bones in the back of their pitching elbow together and/or lengthen the coronoid process of the Ulna bone.

     Ask Mr. Brent Strom and Joel Zumaya how much they enjoyed breaking the olecranon process of the Ulna bone off the shaft of the Ulna bone.

     When will everybody understand that Dr. Fleisig is not qualified to do biomechanical research, much less voice his opinions?


Good Luck Everybody
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