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Orthop J Sports MedOrthop J Sports MedOJSspojsOrthopaedic Journal of Sports Medicine2325-9671SAGE Publications Sage CA: Los Angeles, CA 10.1177/2325967118S0007310.1177_2325967118S00073ArticleRelationship Between Pitcher Fatigue and Medial Elbow Torque in Baseball Pitchers: A Simulated Game Analysis Makhni Eric C. MD, MBA1Meldau Jason E. B.S.2Stephens Jeff 3Okoroha Kelechi MD4Lizzio Vincent A. B.S.2Meta Fabien 2Ahmad Christopher S. MD5Moutzouros Vasilios MD61 Henry Ford Hospital, Novi, MI, USA2 Henry Ford Hospital, Detroit, MI, USA3 Wayne State University, Detroit, MI, USA4 Henry Ford Hospital, Royal Oak, MI, USA5 Columbia University, New York, NY, USA6 Henry Ford Medical Group, Novi, MI, USA27 7 2018 7 2018 6 7 suppl4 2018 AOSSM Annual Meeting Abstracts2325967118S00073© The Author(s) 20182018SAGE PublicationsThis open-access article is published and distributed under the Creative Commons Attribution - NonCommercial - No Derivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits the noncommercial use, distribution, and reproduction of the article in any medium, provided the original author and source are credited. You may not alter, transform, or build upon this article without the permission of the Author(s). For article reuse guidelines, please visit SAGE’s website at http://www.sagepub.com/journals-permissions.Objectives:
The incidence of overuse injury to the elbow in baseball pitchers continues to rise, despite exhaustive efforts at pitch count regulations and emphasis on proper throwing mechanics. The goal of this study was to determine if the medial elbow experiences increased torque levels as the pitcher fatigues through the course of a simulated game.

Methods:
Competitive baseball pitchers were recruited for this simulated game study. Medial elbow torque was assessed using a validated mobile sensor that recorded medial elbow torque during the throwing motion. A radar gun was used to capture pitch velocity for each recorded pitch. Each pitcher completed a simulated game consisting of 6 innings and a standardized pitching scheme of fastballs, curveballs, and change-ups. Visual analog scores (VAS) measuring fatigue were recorded in between each inning. In total, each pitcher threw 90 pitches. Data was recorded every pitch to include ball velocity, medial elbow torque, arm speed, arm rotation, and arm slot.

Results:
A total of 11 pitchers (average age 17.6 years; range 15-20 years) completed the study. No adverse outcomes were noted with use of the mobile sensor. VAS scores increased 0.716 points per inning pitched (p<0.001). Medial elbow torque also was found to increase with successive innings, with an increase of 0.836 Nm each inning (p<0.001), while average pitch velocity was found to decrease as the game progressed (0.28 mile per hour decrease per inning; p<0.001). Fastballs generated the highest amount of medial elbow torque. There were no differences found in arm rotation or arm speed as the game progressed. However, the arm slot was found to decrease with each successive inning (0.731 degree decrease per inning; p<0.001).

Conclusion:
In this simulated game analysis, pitchers were noted to experience increase fatigue after each successive inning. While the average fastball velocity decreased from inning-to-inning, the medial elbow torque was found to increase, signifying a possible risk factor for overuse injury to the medial elbow.

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