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

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

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;102:127-132. Lyman S, et al. Longitudinal study of elbow and shoulder pain in youth baseball pitchers. Med Sci Sports Exerc. 2001 Nov;33(11):1803-10. National Collegiate Athletic Association Sports Sponsorship and Participation Reports. 2014.

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

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)

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.

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.

Tommy John…Epidemic? Professional Baseball Players. A 2012-2013 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. http://jasoncollette.com/wp-content/uploads/2014/05/surgeries.png

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

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?

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

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

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

Risk Factors for Throwing Injuries Overuse Guidelines Biomechanics Throwing v Pitching Pitch Type Don’t forget about the hips Climate Specialization http://cbphysicaltherapy.com/prevent-baseball-overuse-injuries/

Glenohumeral Epiphysiolysis/ Little League Shoulder Throwing athletes from ages 11-16. 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. 2012. Zaremski JL, Herman DC, Vincent KR. Curr Sports Med Rep. 2015. Rizio L, Uribe JW. Clin Sports Med 2001.

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

http://m.mlb.com/sections/pitchsmart/pdf/pitching-guidelines.pdf

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

In Clinic For Parents and Patients http://www.ortho.ufl.edu/sites/ortho.ufl.edu/files/handouts/OSMI-Throwing_Injuries_Handout.pdf

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)

But the real Winners are…

If we do our Job 20 years from now Tommy John injuries will be going down…and shoulder injuries will return to levels seen 20-30 years ago because of people like Dr. Micheo, (NEERU, etc) AND THE AUDIENCE

Rebuttal

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.

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. 2015.

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

Thank You zaremjl@ortho.ufl.edu