Use Your Hips: Elbow Injuries in Youth Baseball Pitchers

The shoulder blade, also known as the scapula, undergoes mechanical and possible structural changes in pitchers. These changes include internal rotation and anterior tilting which can contribute to impingement during the external rotation that occurs during the late cocking phase in pitching (circled in red).2,3 High school pitchers are ~2x more vulnerable to noncontact and overuse shoulder and elbow injuries than position players1 The increased internal rotation of the scapula can increase the abnormal forces on the elbow when in the late cocking phase of pitching.4 As the arm transitions in to the acceleration phase, tension forces are placed on the elbow’s ulnar collateral ligament, made famous by the Tommy John Surgery. As a side note, no surgery makes you stronger. Avoid surgery at all cost by focusing on proper throwing mechanics to reduce the risk of injury. A recent article, “Stride Length and Torso Biomechanics As They Relate To Medial Elbow Injuries In Adolescent Aged Baseball Pitchers: A Clinical Commentary” published in the International Journal of Sports Physical Therapy details the importance of proper torso mechanics and stride length.5 As the pitcher steps towards home plate in the stride, the throwing arm begins external rotation. Proper torso mechanics demand upper and lower body dissociation as the hips drive forward while the throwing elbow reaches its most vulnerable position in max external rotation. This stride length has been reported as 66% of body height in 9-14yo pitchers, increasing 10% in stride length with each year of age.6,7

If you’re a baseball athlete, come see us for a shoulder in-season maintenance program! If you’ve had an injury or struggling with shoulder pain or pitching-related overuse injury, our sports performance rehab can get you back to playing at your best! 

References:

1.     Saper MG, Pierpoint LA, Liu W, Comstock RD, Polousky JD, Andrews JR. Epidemiology of shoulder and elbow injuries among united states high school baseball players: school years 2005-2006 through 2014-2015. Am J Sports Med. 2018;46(1):37-43.

2.     Oyama S, Myers JB, Wassinger CA, Ricci RD, Lephart SM. Asymmetric resting scapular posture in healthy overhead athletes. J Athl Train. 2008;43(6):565-570.

3.     Mihata T, Jun BJ, Bui CNH, et al. Effect of scapular orientation on shoulder internal impingement in a cadaveric model of the cocking phase of throwing. J Bone Joint Surg Am. 2012;94(17):1576-1583.

4.     Itami Y, Mihata T, McGarry MH, et al. Effect of increased scapular internal rotation on glenohumeral external rotation and elbow valgus load in the late cocking phase of throwing motion. Am J Sports Med. 2018;46(13):3182-3188.

5.     Dietz Z, DeWeese D, Shaw N, Huth C, Ball J, Reeves V, Monti R, Bitzel R. Stride Length and Torso Biomechanics As They Relate To Medial Elbow Injuries In Adolescent Aged Baseball pitchers: A Clinical Commentary. Int J Sports Phys Ther. 2022 Jun 1;17(4):732-737.

6.     Sgroi T, Chalmers PN, Riff AJ, et al. Predictors of throwing velocity in youth and adolescent pitchers. J Shoulder Elbow Surg. 2015;24(9):1339-1345.

7.     Fry KE, Pipkin A, Wittman K, Hetzel S, Sherry M. Youth baseball pitching stride length: Normal values and correlation with field testing. Sports Health. 2017;9(3):205-209.