Anterior Shoulder Forces in Professional and Little League Pitchers
Background: The developing musculoskeletal system of a youth pitcher is substantially different from that of the adult professional pitcher, predisposing the younger players to a different set of injuries.
Methods: High-speed videography of 39 professional and 13 youth pitchers were obtained. High-speed motion analysis was performed to calculate average anterior forces and arm positions at maximal force generation.
Results: Professional players generated an average of 33.8+/-14.4 N/kg maximal anterior force, corresponding to 151.9+/-17.0 degrees of external rotation. Youth pitchers generated 16.2+/-3.8 N/kg of anterior forces, corresponding to 118.0+/-23.4 degrees of external rotation. The degree of coronal abduction and horizontal abduction between the 2 groups were not significantly different-92.4+/-9.0 degrees in professionals versus 91.7+/-7.9 degrees in the youth and 11.1+/-11.1 degrees of horizontal abduction in professionals versus 7.8+/-14.1 degrees in the younger throwers. Professional pitchers exerted higher internal rotation torque at 19.4+/-4.1 Nm/kg versus 5.6+/-1.0 Nm/kg in youth, and compressive forces were found to be 121.7+/-21.7 N/kg in professional pitchers compared with 47.5+/-7.6 N/kg in the youth pitchers.
Conclusions: Youth pitchers experience significant anterior shoulder forces and internal rotation torques, although these are lower than professional pitchers.
Sabick, Michelle. (2010). "Anterior Shoulder Forces in Professional and Little League Pitchers". Journal of Pediatric Orthopaedics, 30(1), 1-7.