If your child is a pitcher, he/she has about a fifty-fifty chance of experiencing pain in his/her elbow or shoulder during his/her baseball career.

A 2002 study in the American Journal of Sports Medicine found:

• Roughly half of the 476 youth pitchers studied reported elbow or shoulder pain at least once during the season.
• For each additional 25 pitches thrown after reaching the 50 pitch count, the percentage of pitchers experiencing pain increased.
• The risk of shoulder pain was 2 and a half times greater for pitchers who threw more than 75 pitches per game

• The risk of elbow pain was 3 1/2 times greater for pitchers throwing more than 600 pitches per season
• For pitchers who self-reported pitching while tired, the risk of elbow pain was 6 times greater and the risk of shoulder pain increased four-fold.
• Youth baseball pitchers who threw curveballs or sliders were at an increased risk of elbow and shoulder pain [Note: while two recent studies suggest that throwing a curveball actually puts less stress on the elbow and shoulder than throwing fastballs, some experts, such as world-reknowned orthopedic surgeon Dr. James Andrews of the American Sports Medicine Institute (ASMI), still believe throwing curveballs at an early age can be dangerous; see #12 below].

A 2005 study in the same journal found that overuse was the overriding factor in the development of arm pain among pitchers in youth baseball. That study found that:

• Pitchers who averaged more than 80 pitches per appearance were nearly 4 times more likely to require arm surgery;
• Pitchers who pitched competitively more than 8 months per year were 5 times more likely to require surgery; and

• By age 20, those who pitched on a regular basis with a tired arm were an astounding 36 times more likely to have an elbow or shoulder injury requiring surgery.

Other studies have found that:

• 26% of youth players and 58% of high school pitchers experience elbow pain

• 29% of 9- to 19-year-old boys experience shoulder pain in one study and between 32% and 35% in two other studies (38% in a 2010 study of high school pitchers)

The epidemic of arm injuries suffered by youth baseball pitchers is reflected in the dramatic increase in the number of shoulder and so-called Tommy John elbow (ulnar) ligament-transplant operations performed by Dr. James Andrews at ASMI:

• 9 Tommy John elbow operations from 1995 to 1998
• 65 over the next four years
• 224 from 2003 to 2008
• 2001-2002: total of 13 shoulder operations on teens
• Over next 6 years, 241

Too many pitches, not enough rest

Research by the ASMI and others points to three principal risk factors for injury to youth baseball pitchers: overuse (number of pitches during a game, season, and a year), poor pitching mechanics, and poor physical fitness/physical conditioning.

1. Most baseball arm injuries are not the result of a single traumatic event. Instead, injuries are believe to be due to the cumulative effect of microscopic trauma from the repetitive act of pitching. Overuse occurs throughout the course of a single game, season, or year in the developing baseball player.
2. Poor pitching mechanics has been suggested as a possible risk factor for injury, but such a link has yet to be shown in bio-mechanical or clinical studies.

1. Poor physical fitness/physical conditioning.

Of the three, experts seem to agree that the number of pitches thrown coupled with the lack of appropriate rest periods are the greatest contributor to the increasing incidence of pitcher arm injuries.

Injury prevention tips

1. Watch and respond to signs of fatigue

As a 2009 study by ASMI reported in the journal Sports Health: A Multidisciplinary Approach notes, like pain (see #8 below), "fatigue is generally difficult to quantify because it is a subjective measure that varies among persons." The study recommends using pitch counts, ball velocity, ball location, pitching mechanics, and strength as guides to determining fatigue.

• If a youth pitcher complains of being tired or looks tired, let him rest from pitching and other throwing:

• Like most athletes, pitchers are generally reluctant to tell coaches they feel tired, even when not telling might hurt both the team and the player;

• A pitching coach's observational skills and judgment need to be used to detect fatigue:
  • a tired pitcher exhibits significantly less maximum shoulder rotation and knee flexion and a slightly more upright trunk position at ball release:
    • a tired pitcher's fastball becomes consistently elevated.  One pitching expert says that as a general rule if a young pitcher unintentionally elevates his fastball significantly (4-6 inches) for two hitters in a row, a visit to the mound is in order. If the pitcher fails to make an adjustment on hitter #3, he takes him out.
    • a tired pitcher throws from a different arm slot/angle.
    • a tired pitcher begins to miss locations high and low; pitches wild high and inside to the arm side and wild low and outside to the glove side, says pitching coach Ron Wolforth, are "almost always a sign of significant fatigue and mechanical inefficiency."
  • tired pitchers rely less on the lower body and more on the arm (which puts more strain on the arm)

• tired pitchers experience a drop in velocity.  One prominent baseball expert recommends taking a pitcher out when the drop of average radar velocity exceeds 3% mph.  (although the use of radar guns is not generally recommended; see #9 below).

2. Make sure your child takes a break from pitching/overhand throwing

In certain parts of the country (e.g. Florida, Texas, California), baseball is played year-round. Like other athletes, youth baseball pitchers need to take one season off out of four.

Research shows that youth baseball pitchers who pitch competitively more than 8 months a year are 5 times more likely to require surgery. To reduce the risk of injury, youth baseball pitchers need a period of "active rest" after the baseball season ends and before the next season begins during which they should stay physically active to maintain conditioning but refrain from overhand throwing of any kind:

• "Active rest" and no overhead throwing of any kind for at least 2-3 months per year (4 months is better). In other words, not only should a baseball player not participate in throwing drills, but should not participate in other activities that put stress on the shoulder (javelin throwing, football quarterback, softball, competitive swimming etc.)

• No competitive baseball pitching for at least 4 months per year.

3. Follow pitch count limits and rest periods

Based on research showing a strong link between the number of pitches thrown and increased risk of arm injury, Little League Baseball instituted daily pitch limits and mandatory rest periods between pitching appearances in 2007, which it has updated for the 2010 spring season. Dr. James Andrews of the ASMI, perhaps the world's foremost authority on pitching injuries, hailed the Little League pitch limit and rest rules as "one of the most important injury prevention steps ever initiated in youth baseball." USA Baseball recommends pitch limits but does not mandate them.

At least one pitching expert, however, believes that pitch count per inning is far more important than total pitch count. 

A note of extreme caution to parents of youth baseball pitchers on independent travel and all-star teams competing in independently-operated tournaments: they may have NO rules at all on pitch limits and rest.

4. Avoid allowing your child to pitch on multiple teams with overlapping seasons

More and more youth baseball players play on multiple teams at the same time. While playing on multiple teams may give him/her a chance to develop his skills, and while the amount of pitching may be limited by league rule or the judgment of the coaches, playing on multiple teams with overlapping seasons increases the risk that he/she may end up exceeding pitch limits because of a lack of communication and coordination between coaches, who are likely to end up blaming each other if your child suffers an arm injury. If you do let your child play on more than one team at once, it may be up to you, as his parent, to keep track your child's pitch counts and days off and to insist that the coaches not exceed those overall limits.

5. Teach good throwing mechanics as early as possible

A video analysis of youth pitchers reported in a 2009 article in the American Journal of Sports Medicine reported that adolescent pitchers (ages 14 to 18) performed better than youth pitchers (ages 9 to 13) on five simple measures of pitching mechanics (leading with the hips, hand-on-top position, arm in throwing position, closed-shoulder position, and stride foot toward home plate), with 80% of the adolescent pitchers performing 3 or more parameters correctly compared with only 64% in the younger age group (although, unexpectedly, youth pitchers (86%) outperformed their older counterparts (66%) on the stride foot toward home plate measure).

The study suggests that the five measures of pitching mechanics studied may be developmental milestones for youth pitchers as they improve their mechanics over the years and learn to pitch, although it is unclear whether the development is a function of coaching and instruction or whether athletes more easily perform them as neuromuscular function improves with age.

• Proper positioning of the throwing arm during all phases of the pitching motion can reduce the number of injuries. According to Thomas J. Gill, M.D., Department of Orthopaedics at Massachusetts General Hospital, and Boston Red Sox team physician, researchers found that "pitcher's arm movements during different phases of the pitching motion, if performed incorrectly, can cause injury." Researchers identified four problem areas: 
  • Maximum shoulder rotation: A pitcher needs to rotate his body more to avoid placing too much stress on the arm and shoulder, which occurs when his arm is positioned too far behind his body.
  • Improper elbow angle: The pitcher's arm needs to be away from his body when the ball is released; the closer the arm is to the body, the more potential for injury.
  • Arm lagging behind the body. When a pitcher gets tired, his arm tends to lag behind his body, placing undue stress on the shoulder.

• Excessive ball speed. Trying to throw too hard can be harmful, especially for young players, warns Dr. Gill.

Players should follow a step-by-step approach to learning how to pitch:

1. Basic throwing.
2. Fastball pitching. At all levels of competition, a good fastball is the foundation for successful pitching; thus, the young baseball pitcher should master the fastball first.
3. Change-up pitching (studies show it places the least amount of stress on the arm)

1. Curveball (see #12 below)

Use of lighter balls may lessen the risk of overuse injury in pitchers between ages 9 and 12.

6. Make sure your child is properly conditioned.

• "Most pitching injuries are caused by overuse, which may be the result of insufficient conditioning of certain muscles," says Dr. Gill.

• All pitchers should incorporate conditioning and stretching exercises for the shoulder into an overall conditioning program. The muscles in the front of the arm are naturally stronger. Because many shoulder injuries result from weaker muscles in the back of the arm that are used to stop the pitching motion, the conditioning program should emphasize building up those muscles. "Exercise routines such as cross-body curls, using light dumbbell weights, and wall push-ups are useful for strengthening shoulder muscles," Dr. Gill says.  For more shoulder stretching and conditioning exercises, click here.

7. Make sure your child properly warms up and stretches.

• Research shows that cold muscles are more injury prone. While a proper warm-up is important for all youth athletes, it is particularly critical during a growth spurt, when your child's muscles and tendons are tight. Experts, including the American Academy of Orthopedic Surgeons , recommend that your child warm up by:
  • Dynamic stretching: Do jumping jacks, jogging or walking in place for 3 to 5 minutes to get the blood moving through the muscles and ligaments.
  • Static stretching: Then slowly and gently stretching, holding each stretch for 30 seconds. Pitchers should concentrate on stretching their arms, shoulders, neck and wrists, in addition to stretching their legs.

• Your child shouldn't start throwing the ball hard right away, especially in cold weather. He should begin by "soft tossing" and then gradually increase the distance and velocity of his throws as his arm gets loose and warm.

8. Never allow your child to play through pain

The stories about youth baseball pitchers pitching in pain to the point of injury abound. Any persistent pain is a sign of a chronic (i.e. overuse) or acute injury that should sideline a child from playing until it subsides. Teach your child not to play through pain. If your child gets injured, see your doctor. Follow all the doctor's orders for recovery and get the doctor's (or physical therapist's ) okay before allowing your child to play again.

9. Avoid using radar guns

Pitchers may be unable to resist the temptation to overthrow, subjecting them to increased risk of injury. Note: some experts, including Ron Wolforth of Texas Baseball Ranch and Pitching Central, recommend use of radar guns, not out of an obsession with velocity but because of its value as a tool to measure pitcher fatigue (see #1 above).

10. Avoid showcases

Showcases provide young players the opportunity to show off their skills to scouts at higher levels of baseball. As USA Baseball notes, "Unfortunately, showcases often occur near the end of the player's season, when players are often fatiqued and require rest and recovery. In other instances, players participate in a showcase after a prolonged period since the league ended and without adequate preparation to throw hard again. It is without a doubt that young throwers will try to overthrow at these events in an effort to impress the scouts, which further increases the risk of serious arm injury."

11. Don't let pitchers be catchers too

The pitcher-catcher combination results in too many throws and may increase the risk of injury. Little League Baseball has institituted a new rule for 2010 banning any pitcher who delivers 41 or more pitches in a game from going behind the plate to play catcher for the remainder of the day.

12. Consider delayed throwing of the curveball

Two recent studies, both appearing in the American Journal of Sports Medicine, appear to pour cold water on earlier studies and the conventional wisdom that throwing curveballs leads to increased risk of arm injury in young pitchers.

Glenn Fleisig, chairman of research at ASMI and co-author of one of the two studies, told the New York Times flatly that he didn't "think throwing curveballs at any age is the factor that is going to lead to an injury." Carl Nissen, the author of the other study, said in the same Times article that he could "comfortably stand up and say the curveball is not [part of the injury] problem."

Interviewed by the Times, however, Dr. James Andrews of the ASMI, who had previously recommended against pitchers throwing curveballs before age 14, warned that the new findings "may do more harm than good" because he feared parents and coaches would interpret the findings improperly as a license to teach kids to throw too many curves or begin when they were too young.

He also cautioned that the study he co-authored with Fleiseg, his longtime ASMI colleague,  had limitations because it was conducted under laboratory, not game conditions and continues to believe that, when young pitchers are tired, throwing curves could still be dangerous, citing the story of a 12-year-old on whom he operated the day of the interview who at age 12 had torn the ulnar collateral ligament in his elbow in two after throwing 30-something curveballs in a row, the last one snapping his elbow.