Is An Epidemic Upon Us? Too Many Arm Injuries

By Geoff Zahn,
Former Major League Pitcher and Head Baseball Coach, University of Michigan
May 12, 2008
The last few years as I was doing Color Commentary for College Baseball telecasts, I noticed that many of the college teams we were broadcasting had at least one pitcher out for the year recovering from elbow ulnar collateral ligament (UCL) reconstruction, commonly known as Tommy John surgery.  It struck me at the time to be a high level of injuries to young arms.  Recently my observation has been found to be true beyond what I first believed.


After just reading an article from the “American Journal of Sports Medicine” titled “A Biomechanical Comparison of Youth Baseball Pitches: Is the Curveball potentially Harmful?” (1)  I was shocked by the increasing numbers of UCL reconstruction surgeries that the senior author of this study, Dr. James R Andrews, was doing, especially on High School pitchers.
“In our own experience, the senior author (J.R.A,) reconstructed the UCLs of 119 pitchers between 1995 and 1998, 354 pitchers between 1999 and 2002, and 619 pitchers between 2003 and 2006.  Besides the increase of total surgeries during these  3 consecutive 4-year periods, there has been an alarming increase in the number (percentage) of surgeries on high school pitchers-from 9 (8%) to 61 (17%) to 201 (24%).” (1)


The conclusions and clinical relevance of this study of the curveball did not surprise me.  The findings were that the fastball, not the curve ball put heavier shoulder and elbow loads on the throwing arm and that “the curveball may not be more potentially harmful than the fastball for youth pitchers”.  They then related, “This finding is consistent with recent epidemiologic research indicating that amount of pitching (emphasis added) is a stronger risk factor than type of pitches thrown.”  (1)


In the three time periods mentioned spanning twelve years, there was a six-fold increase, from 119 to 619 in total UCL reconstruction surgeries, and a twenty-fold increase from 9 to 201, in high school pitchers’ UCL surgeries over that same time span.  In addition, I sense an increase in the number of Labrum tears in the throwing shoulders of younger pitchers where that injury seemed to be reserved for older pitchers who had pitched for a period of time.
There is no doubt that advances in surgical technique and the shorter times of recovery have caused more pitchers to get injuries surgically repaired and to continue to pitch.  In the past when arms would break down, pitchers would be more prone to stop pitching altogether.  Now great advances in the medical field allow many pitchers to come back from what used to be career ending injuries.


What makes analysis of UCL injuries and Labrum injuries difficult is that they generally appear over time and don’t cause debilitation all at once.  My fear is that college or pro pitchers that develop these injuries actually came to college or pro ball with the problem of a frayed UCL or torn Labrum that was initiated years before.  Regardless, pitchers’ arm injuries are on the rise, and all involved in the game need to take heed and work to head off this potential epidemic.


In the last fifteen years, I believe there are new potential risk factors to look at that may be contributing to arm injuries.  At the same time, there have been many steps taken to try to limit injuries to young pitchers.  Some of those positive steps are the advent of pitch counts, research which has given a clearer picture of proper mechanics, advanced conditioning programs available at schools and sports academies and accessable over the internet, and in general, more awareness by parents and coaches of the dangers to the arm.


It is wise to look at the changes that have occurred in the game over recent years and assess whether they could potentially be contributing to greater risk of arm injuries.


  • Overuse Syndrome: Amount of pitching: Pitches thrown in a game, week, season, and year.
  • Velocity:  The obsession with velocity by coaches, pitchers, and parents
  • Mechanics: geared for velocity
  • Showcases, Travel Teams and Prospect Camps
  • Weightlifting and Conditioning: Increased at all HS and College levels in all sports
  • Sedentary Lifestyle
  • Money


Overuse Syndrome and Showcases, Travel Teams and Prospect Camps:

If you talk to older pitching coaches, many of them will say that kids don’t throw enough today.  They are quick to point out that many of the old time pitchers threw every day and pitched toward three hundred innings a year.  So how do you have pitchers throw more and yet stay away from pitching too much?  The answer lies in pitching or throwing hard when fatigued.  Pitching when the arm is short term or long term fatigued leads to cumulative trauma to the joints which never get to recover.


Pitch count limitations have been a great help to easing overuse of the arm.  However, the advent of showcases, travel teams with weekend tournaments, and Prospect Camps have countered some of the good being done.  In the case of weekend tournaments, coaches want to get as much out of their best pitchers as possible.  Therefore, they divide up their best pitcher’s pitch count in different games over the weekend, and pitchers are throwing in games before their arms are fully recovered.  This can go on weekend after weekend on travel teams, possibly contributing to long term fatigue of the arm. 
Withshowcases and prospect camps scheduled throughout the year, pitchers may show up and throw for a radar gun after not throwing for weeks or after pitching recently before the showcase or camp.  In the off season this can become a mad cycle of throwing as hard as you can for a showcase, feeling fatigued, resting and then heading to the next showcase to repeat the process.


Another increasing phenomenon is parents having their sons play in more than one league.  Pitch count limitations don’t cross league lines so a young pitcher may be abusing his arm and the respective coaches have no idea of the combined pitches their young pitcher is throwing.  That remedy requires common sense by the parents.


I would like to see better rules that would either limit pitchers throwing only once on a weekend or, at least, after so many pitches, giving him proper days off.  Gil Patterson, current pitching coordinator for the Oakland A’s, has the following restrictions on pitching consecutive days. “In general 20 pitches per game, with one day rest in between. With 30 pitches, two days off.  With 45 pitches, three days off.  With 60 pitches, four days off.  (Starters have a limitation of 100 pitches with four days rest in between starts.) These pitch counts are for young men 19 and older, who train to do this for a living.” (2)


Shouldn’t coaches and leagues be more conservative than pro ball when it comes to protecting younger arms?  These are young arms with joints that don’t have their growth plates closed yet.


The Oakland Organization also likes to see their pitchers at least play catch every day and keep the feel of their pitches, working on control and proper spin.  That, to me, is called active rest and actually, in a non injured arm, helps in normal recovery by getting blood flow to the arm.  Obviously, if an arm is over fatigued you would give more rest.  In addition, different body types and mechanics must be taken into account, and every effort should be made to help a youngster know his arm and allow him to get rest when he thinks he needs it. 
Young pitchers who are fatigued should never be asked if they can pitch an inning or two.  Being competitive and not wanting to let their teammates down they will never say no, even if their arm is killing them.  No championship is worth jeopardizing a young pitcher’s arm.


Gil Patterson sums it up well; “So, if I am in control of younger pitchers, I would make sure that I am responsible enough to put their careers first (before) of any game.  Sometimes people say they have all off-season to rest, but you can be injured to the degree that ten off seasons will not help”. (2)  Coaches must realize that risking a young man’s arm by pitching him when his arm is fatigued could be causing injury that may not show up to the point of debilitation for a couple of years.



The obsession with velocity by coaches, pitchers, and parents

  • Velocity camps and programs are being offered by sports academies across America.
  • A student came back to me after attending a college prospect camp and reported that the head coach’s opening comment was that if you were right handed and didn’t throw at least 87 mph you were wasting your time at the camp.
  • Kids go to showcases and, just before their first pitch, 20 or more coaches’ radar speed guns come up.
  • Coaches include velocity exercises in their teaching.
  • High school kids are being judged by how hard they throw more than getting people out and winning.
  • Every young man who has come to me for lessons in the last few years wants to see an increase in velocity.
  • Dads of 11, 12, 13 year olds are showing up at pitching lessons with their own radar gun to follow the progress of increased velocity.
  • Reported in ‘The Indiana Daily Student’ article titled ‘Perceived Miracle Elbow Surgery Becoming Common Among Younger Pitchers’, “His father simply wanted him (his son) to have the surgery (Tommy John) in hopes his arm would come out stronger afterward.” (3)  There was nothing wrong with his arm.


The advent of the MPH scoreboard at Major League games and the obsession with velocity by college and high school coaches has caused the realization of parents that unless their son hits a certain mph he will not have much chance of getting a college scholarship let alone a professional contract.  While velocity has always been a factor in judging pitching talent, it has never dominated like it does today.  It used to be, if you knew how to pitch and you won, you would have a chance.  Now it starts with velocity.  I wonder if we ever would have seen the likes of Tom Glavine, Tommy John, Greg Maddox, Kenny Rogers, and a host of other ML pitchers if today’s standard of velocity were applied.


Because of this pressure more and more parents want to know if they can add mph to their son’s velocity, and they go to private instructors with that in mind.  It has become at least as important as arm safety.


All of this has created an attitude of velocity and stuff (break on breaking balls and change-ups) being more important than location and learning how to pitch and set up hitters in order to win.  With coaches calling pitches, we are turning kids into pitching robots that are brain dead.  It used to be that calling pitches was mostly done in college and sometimes in pro ball.  Now it reaches down to little league.  Pitchers are just learning how to throw pitches while relying on coaches to set up hitters and get them through games.  The fun of pitching is learning how to get hitters out and throwing those pitches you know will work in different situations.  The problem affects pitchers all the way up to the Big Leagues.  In an exhibition game this spring, Jim Leyland made a comment after his Tigers had played the New York Yankees.  The gist of it was that there were several pitchers out there today throwing over 95 mph and there were around twenty  runs scored combined between the two teams.  What does that tell you about the importance of velocity over knowing how to pitch?


Let’s get back to emphasizing pitching over velocity and allow kids to learn how to pitch by calling their own game and helping them learn through experience.



Geared for velocity

Biomechanical study of pitchers deliveries has brought better knowledge of the delivery and a better understanding of how power (velocity) is most efficiently generated.  It is not a stagnant science, and new information helps in the development of teaching techniques and drills.  The teaching of mechanics should be for the purpose of helping a pitcher to throw as efficiently as possible which will allow him to have his greatest velocity while putting the least amount of stress on the shoulder and elbow joints.  It should not be for the purpose of producing velocity first and then worry about efficiency of the throw.
Over my eighteen years of working with youngsters from age eight on up, I have observed a couple of concepts that I believe are vital in helping young pitchers to become efficient. This short summary is not meant to be exhaustive but to be applied to the subject of arm injuries.
I am starting with the assumption, which I believe most research supports, that power is most efficient when it is initiated in the lower body.  For the sake of this discussion I will use the term lower body thrower to mean one who, in the sequence of the throw, starts hip rotation before shoulder turn, and an upper body thrower as one who, in the sequence of the throw,  starts shoulder turn before hip turn.


Over my first five years of teaching several youngsters between the ages of eight to ten, I noticed that all but one came to me as an upper body thrower.  Their heads moved a tremendous amount during the throw, and their arms were in a poor position when acceleration started.  The throwing action looked more like slinging the ball than throwing it.  At first, I gave drill work and centered my techniques to get them to begin to generate their power out of their lower body instead of their shoulders.  Finally, I decided to put a tennis ball in their hands and then initiate the drill work.  They immediately grasped the ideas as well as the 12 and 13 year olds I was teaching.  My conclusion, which I still believe today, is that the baseball is both too big and too heavy for young pitchers and that they begin as upper body throwers because of that.  I believe a progression must take place in a pitcher from an upper body thrower to a lower body thrower as he gets older and stronger.


An analysis done by Dr. Frank Jobe, among others, in 1984, seems to support that progression.  The study compared professional and amateur pitchers, analyzing muscle activity in the shoulder during pitching.  They found that professional pitchers were more efficient during the acceleration phase of the throw primarily using the inward rotator of the rotator cuff group, the subscapularis, and the latissimus dorsi muscle, a large muscle in the back “whereas the amateurs activated the other rotator cuff muscles and the biceps brachii for power.”  (4)  What this is saying is that the professional pitchers were more efficient in throwing using bigger muscles to coordinate greater pitching velocities while the amateurs used the smaller muscles of the rotator cuff and the biceps to try to produce velocity.  This, to me, is part of the progression that most pitchers must go through to become more efficient.  Understanding this progression helps to understand why pitchers do the things they do and makes the pathway to helping them easier.  I believe it is imperative to move pitchers through this progression and at the same time have them strengthen their rotator cuff and muscles around the back, shoulder, and elbow with a good stability program.
A second concept is that it is extremely important that the arm and shoulder be in the proper position at stride foot contact. (SFC)  The previously stated research states, “Positioning the shoulder and arm correctly in space is also important in determining the amount of energy that is transferred to the baseball.” (4)  I believe this positioning is critical for coordination of the throw and for consistent control of the pitch.  The following pictures are similar to pictures found in a study conducted in 2007 by Miyashita et al. (5)




                                             IR                                      Extension
Figure 1.  “The typical presentations of throwing mechanics at SFC (stride foot contact):  The player on the left side demonstrates “proper” shoulder angle at SFC that is frequently seen in non-injured baseball players.  When compared to the player on the left side, the player on the center demonstrates greater shoulder internal rotation angle, and the player on the right demonstrates greater shoulder extension angle at SFC.” (5)


Although their study was not exhaustive, at the time their conclusion was: “Therefore avoiding excessive shoulder IR (inward rotation) and extension angles at SFC, strengthening IR muscles and maintaining the passive ROM (range of motion) of ER (external rotation) in the normal range may decrease the risk of throwing injuries.” (5)


I have studied pitching motions for years and looked at many Major League pitchers with long successful careers. Through that study I believe proper arm angle at SFC is critical because it puts the arm in the best position to receive the action and power of hip rotation.  It is very similar to a hitter that gets his hands in a hitting position by the time his stride foot makes contact with the ground.  This proper arm angle at SFC is a critical aspect of safe mechanics and gives the greatest chance for consistent control.




Weightlifting and Conditioning:

Increased at all HS and College levels in all sports

There is no question that athletes are participating in weight training and conditioning at an earlier age.  This is happening, not just in baseball, but in most sports, especially football and basketball.  Many times weight training programs overlap sports seasons where you may have, for example, an athlete participating in baseball and yet doing weight training for football.  Many of these programs are mandatory for participation in a sport and develop a different kind of strength than is used in delivering a baseball 80 to 90 mph.


At the same time, training and conditioning programs can be found readily on the internet so that many times young, ambitious athletes are combining one or two programs with another one to speed up their strength development.


Another consideration must be the obtaining and use of supplements and/or performance enhancing drugs.  It is naivety to think that with the need for testing in college and pro ball that the use of these supplements has not reached our youth.


While strength is important, there are some questions that need to be answered in regards to long term health of the shoulder and elbow in throwing:

  • Are young pitchers getting too strong for their elbow and shoulder joints, especially when their growth plates are not yet closed?
  • What are the long range effects of heavy weight training on the shoulder and elbow joint with exercises like the bench press, military press, and biceps and triceps curls?
  • At what age or stage of development should weight training safely start?
  • Do heavy ball velocity exercises where a young pitchers throws all out possibly have a long range negative impact on the shoulder or elbow?
  • Are some programs over strengthening groups of muscles without strengthening the antagonistic muscles in the right proportion for that sport?


Sedentary Lifestyle

Even though there are regular leagues, showcases, travel teams, all-star games, fall leagues, winter leagues, private lessons, and training and conditioning classes, pitchers and athletes in general are spending less time outside.  Everything is organized with little free time to just be outside playing pick-up games with peers.  We live in an instant society where we want everything right now in a compact form and don’t want to spend a lot of time doing it.  Kids show up for practice or private lessons or games and go home.  We joke about a Play Station generation but it does lead to a more sedentary lifestyle.


There is a different strength and endurance that develops from being outside and active all day.  Yes it is true that the older generation of pitchers usually grew up throwing something all the time whether it was baseballs or rocks or snowballs or shooting baskets. They participated in a lot of activity outside the time of organized practice.


Now everything is concentrated and compacted into organized practices or workouts.  We expect velocity class to make up for hundreds of throws and we expect mechanics class to cure all woes.  We also think that an hour of weight training two or three times a week will help a pitcher throw harder and longer instead of long ours of playing and throwing outside.


There are no easy packages for success.  If pitchers want to improve their endurance, they have to train themselves by throwing over long periods of time.  If they want to have better control, they have to train their brain to tell their fingers how to make the minute adjustments to throw a pitch just off the corner or on the corner.  That takes monotonous repetition with feel and concentration.  It can’t be done in a 20 pitch bullpen or a half hour pitching lesson.  While they are doing that monotonous repetition, conditioning to throw is taking place.


The kids that are active are the ones involved in multiple sports.  They are overloaded with organized play.  In the summer, a player might have summer football league, summer basketball league and his regular summer baseball team practices and games.


Is education the answer or do coaches and parents and administrators need to rethink playing seasons, conditioning, and types of practice?




The dream of the big leagues, the cost of playing the game today, and no money for research:

  • I had a dad pull me aside after his 9 year olds first lesson. “Does he have a chance?” he whispered out of the range of his son.  “A chance for what?”, I asked back. “A chance at making the Big Leagues”, he answered.  What has happened?  Twenty two year old Yankees pitcher,Joba Chamberlain, stands to make millions for his 100 mph fastball.  Guys immediately identify with the Verlander’s and Zumaya’s and the chance for millions at such a young age.  Moms and dads dream of the big bucks, and their sons get caught up in it.  Parents see all the radar guns at showcases and the prerequisite of throwing hard to be considered for a scholarship.  90 mph + probably means a D1 scholarship somewhere.


While coaching at Michigan, I actually had a family ask me how I was going to position their son for the (ML) draft.  It wasn’t about the fun of the game or about learning to play the game better, it was about strategy to get a better position in the draft to get more money.


What kind of pressure does it put on a young man to worry about his velocity and how much money he is going to make, or what kind of scholarship he can get?  That is putting the proverbial cart before the horse.  Success starts with passion and love of the game.  That drives one past heartache and setbacks to persevere on the road to becoming proficient enough to win and raise the level of play around you.  It’s about realizing potential and striving to get better, never being satisfied.  The money will take care of itself.  How many arms have been ruined because pitchers didn’t take time off when they knew they were hurt because they felt they might lose a scholarship or a big contract?


        • Baseball has become an upper middle class sport in America.  It takes money to get private lessons or to play on privileged travel teams or to participate in showcases.  It is only those with the money that get that kind of teaching and exposure.  Hats off to MLB for their RBI program and reaching out to more youth to play the game.  We need more of that.


  • Much research is needed.  That means someone has to pay for it.  In the case of pitchers’ labrum tears and ulnar collateral ligament rupture, that research will take time.  Because it is a specialized injury to a selective number of people, it is much harder to get grant money to study it.  Many thanks need to go to private organizations like the Kerlan-Jobe Orthopaedic Clinic, and the American Sports Medicine Institute, for their many years of research and advances in sports medicine for the treatment and prevention of pitching injuries.


Summary and Recommendations

There have always been pitchers that come up with bad arms.  Part of it is genetic.  Some pitchers cartilage breaks down, others have ligament problems, still others develop bone spurs and some have almost no problems.  Young pitchers have always thrown breaking balls, and they have thrown without proper conditioning or warm-up.  However the increase in arm injuries, especially to the ulnar collateral ligament in the last few years needs to be addressed.  This short review has pointed out some of the changes in the game over the last 10 to 15 years.  Some of the changes, like pitch counts, are good, and some may need research to determine their value to the safety of pitchers’ arms.


Money is needed for research.  We, in baseball, need to explore avenues of income for grants.  Corporate sponsors of youth leagues from Little League to Connie Mack should be made aware of the increasing occurrence of arm injuries and be encouraged to give money for research.  It is also in MLB’s interest to sponsor research as it eventually helps promote the game.


One of the keys is education.  There are many fine doctors doing research on the pitching motion and on injuries. The information gained has to be translated and put into the coaches’ and parents’ hands in a timely matter.  There has got to be more cooperation between coaches/teachers and doctors/researchers.



  • Look to standardize throughout all youth leagues, pitch counts per game, per consecutive 7 day period, and per year for different age groups.  Also to standardize the amount of rest given after so many pitches.
  • Research whether using a smaller and lighter ball for 8-10 yr olds would make a difference in stress on pitchers’ arms and whether it would increase velocity to the point of being dangerous.
  • Deemphasize the importance of velocity in young pitchers and emphasize learning how to pitch.
  • Give the game back to our youth and let pitchers and catchers call their own game until they at least get to college.
  • Continue research on efficient mechanics.
  • Do research to answer the questions listed above concerning weight training and conditioning.
  • Encourage kids to spend more time outdoors playing pick up games with their peers away from constant adult supervision.


These recommendations are by no means exhaustive but are meant to spur interest and involvement to the point of not just talking about protecting young arms but to actually cause something to be done about it.  The problem of arm injuries does not carry a one cause solution but will require work, cooperation and common sense by all involved for the good of the game.



1.    “A Biomechanical Comparison of Youth Baseball Pitches: Is the Curveball Potentially Harmful?”  by Shouchen Dun, Jeremy Loftice, Glen S. Fleisig, David Kingsley and James R. Andrews. American Journal of Sports Medicine 2008; 36:686 published online Nov 30, 2007


2.  “High School Baseball Pitch Counts” by Gil Patterson,


3.  “Perceived Miracle Elbow Surgery Becoming Common Among Younger Pitchers”  by Zachery Osterman, Indians Daily Student 4/18/2008


4.  “A Comparative Electromyographic Analysis of the Shoulder During Pitching: Professional versus Amateur Pitchers”  by Ivan D. Gowan, Frank W. Jobe, James E Tibone, Jacquelin Perry and Diane R. Moynes, American Journal of Sports Medicine. 1987; 15; 586


5.  Relationship Between maximum Shoulder External rotation Angle During Throwing and Physical Variables”  by Koji Miyashita, Yukio Urabe, Hirokazu Kobayashi, Kiyoshi Yokoe, Sentaro Kushida, Morio Kawamura and Kunio Ida,  Journal of Sports Science and Medicine (2008) 7, 47-53  accepted 12 November 2007 / published online 1 March 2008


Geoff Zahn was a Major League pitcher for 12 years, winning more than 100 games while pitching for the Dodgers, Cubs, Twins, and Angels. He served as the head baseball coach at the University of Michigan for six years. Geoff has been a clinician and speaker for more than 25 years and currently teaches and consults with pitchers from youth leagues to the big leagues through his Master Pitching Institute and the Michigan Sports Academy. You can reach him through