1. AAPMR Annual Meeting| Boston, MA| October 3rd, 2015
What is better for injury prevention in the young overhand athlete? Volume or mechanics
AAPMR Annual Meeting| Boston, MA| October 3rd, 2015
Jason L. Zaremski, M.D., CAQSM
Assistant Professor, Department of Orthopaedics & Rehabilitation
Divisions of PM&R, Sports Medicine, & Research, University of Florida

2. Goals
Review risk factors for overuse throwing injuries in the overhead population
Establish correlation that Volume Outweighs Biomechanics

3. Epidemiology-Baseball
>10,000 baseball players in NCAA Division I baseball
500,000 HS aged baseball players in the US
Shoulder and/or elbow pain ranges from 17% to 45% in one season.
Adams JE. Injury to the throwing arm: a study of traumatic changes in the elbow joints of boy baseball players. Calif Med. 1965;102:
Lyman S, et al. Longitudinal study of elbow and shoulder pain in youth baseball pitchers. Med Sci Sports Exerc Nov;33(11):
National Collegiate Athletic Association Sports Sponsorship and Participation Reports

4. Incidence of UCL injury in 15-19 year olds > 9% between 2007 and 2011
50% of 9-14 yr old players have experienced elbow &/or shoulder pain during play
Lyman et al: AJSM ’12
Surgeries appear to be increasing in young baseball players
Fleisig et al: J Sports Health ’12, Erickson AJSM ‘15

5. Risk Factors Overuse Throwing
Fatigue from Overuse
Fleisig 2011 AJSM, Dale N Am J Sports Phys Ther 2007, Olsen AJSM 2006, Many more
Guidelines
MLB Pitch Smart
Climate
Erickson OJSM 2014, Zaremski 2015
Specialization
Specialization Position Statement DiFiori AMSSM
Or is it due to Biomechanics
Throwing v Pitching
ROM, TROM, GIRD
Wilk et al, AJSM 2014; Hurd JAT 2012
Pitch Type
Controversial (specifically Curve Ball)

6. NY Times 2012
“For pitchers with proper mechanics, the force of throwing a curveball is no greater than for a fastball.
Many kids don’t have proper mechanics or enough neuromuscular control, or they are fatigued when throwing curveballs.

7. If your arm hurts Don’t Throw
What do we tell our young throwers. If your arm hurts don’t throw. If not, you may end up like any of these athletes over the course of many years.

8. Tommy John…Epidemic?
Professional Baseball Players. A survey of active players found that 25% of Major League pitchers and 15% of Minor League pitchers had undergone Tommy John surgery at some point in their careers.

9. Pitching with Arm Fatigue
Average > 80 pitches = 4x risk of surgery
Pitch competitively > 8 months/year = 5x likelihood of injury
Pitching regularly with fatigued arm = 36x as likely to have an injury and potentially need surgery!
Olsen SJ, et al. AJSM. 2006

10. Youth baseball pitchers are at increased risk for throwing injuries based on the volume of pitches thrown per game and per season, fatigue, and poor biomechanics more so than pitch type…but which came first?

11. Volume and Over-Exposure? Climate
Does Climate Matter? A Comparison of Ulnar Collateral Ligament Reconstruction in Collegiate Baseball Pitchers in a Northern versus Southern Conference
Volume and Over-Exposure? Climate
Zaremski JL, et al. In Press

12. 1. SEC v Big Ten Pitchers from 2008-2014 2
1. SEC v Big Ten Pitchers from High School Pitching Location

13. Climate and Overuse at Professional Levels
Warm Weather > Cold Weather
Younger
Played Less years in MLB than Cold Weather Pitchers

14. Risk Factors for Throwing Injuries
Overuse
Guidelines
Biomechanics
Throwing v Pitching
Pitch Type
Don’t forget about the hips
Climate
Specialization

15. Glenohumeral Epiphysiolysis/ Little League Shoulder
Throwing athletes from ages
Widening of the physis resulting in a Salter Harris I fracture.
Due to weaker developing epiphyseal plates, torque during Max external shoulder rotation, and excessive laxity may predispose the young thrower to this type of injury.
From Throwing Too Much without Rest!
Zaremski JL, Krabak BJ. PMR
Zaremski JL, Herman DC, Vincent KR. Curr Sports Med Rep
Rizio L, Uribe JW. Clin Sports Med 2001.

16. Retrospective study
N = 2,372, ages 15-25, underwent MRI for shoulder pain.
The majority of the patients were baseball pitchers.
Results/Analysis: Throwing >100 pitches/week = risk factor for developing acromial apophysiolysis.
Among the patients with this overuse injury:
40% threw >100 pitches/week
8% in the control group

18. Recommended Rest Guidelines
Watch and respond to signs of fatigue.
No overhead throwing of any kind for at least 2-3 months/year (4 months is preferred).
No competitive baseball pitching for at least 4 months/year.
Limits for pitch counts and days rest.
Avoid pitching on multiple teams.
Good throwing mechanics.
ASMI Position Paper

19. In Clinic For Parents and Patients

20. Adding Up the Known Risk Factors…
VOLUME
1. Pitching when fatigued
2. Pitching too many innings/year
3. Not enough rest from throwing at end season
4. Too many pitches in a game, week, year
5. Pitching consecutive days
6. Playing on multiple teams & leagues
BIOMECHANICS
Poor Pitching Mechanics
ROM (Shoulder, Hip)

21. But the real Winners are…

22. If we do our Job
20 years from now Tommy John injuries will be going down…and shoulder injuries will return to levels seen years ago because of people like Dr. Micheo, (NEERU, etc) AND THE AUDIENCE

23. Rebuttal

24. Biomechanics of Different Pitches
Significant kinematic (motion) differences between the fastball and curveball but few kinetic (motion + force) differences. Fleisig GS, et al. AJSM 2006.
Moments on the shoulder and elbow were less when throwing a curveball than when throwing a fastball. In each comparison, the fastball demonstrated higher moments for each individual pitcher for both joints. Nissen CW, et al. AJSM 2009.
Elbow and shoulder loads were the greatest in the fastball and least in the change-up. Dun S, et al. AJSM 2008.
At different levels (Youth, HS, College, Pro) kinetic variation were non-significant when analyzing Fastballs. Fleisig GS, et al. Sports Biomech 2009.

25. The epidemiologic evidence to support limitations on the curveball is lacking rigor in study design.
The current biomechanical evidence does not support limiting the use of curveballs at any level of baseball.
Strengthen the rotator cuff muscles as well as the forearm muscles to train for the curveball.
Support teaching proper mechanics and use of the changeup to prevent arm injuries
Grantham WJ, Iyengar JJ, Byram IR, Ahmad CS. The curveball as a risk factor for injury: a systematic review. Sports Health

26. Post UCL
So if there were no biomechanical changes UCL-R v Control after more than 1 year of intense Rehab and Pitching biomechanics analysis, the only conclusion is that Pitching Too Much Resulted in the Injury
Results:
There were no differences in pitching biomechanics between the UCLr group and the control group.
There were also no differences in PROM between the 2 groups.
Fleisig GS, et al. Biomechanical Performance of Baseball Pitchers With a History of Ulnar Collateral Ligament Reconstruction. Am J Sports Med. 2015

28. Thank You