Arm Pain in Youth Baseball Players: A Survey of Healthy Players (Open Access)
Authors: Makhni, Eric C; Morrow, Zachary S.; Luchetti, Timothy J; Mishra-Kalyani, Pallavi S; Gualtieri, Anthony P; Lee, Randall W Ahmad, Christopher S.
Of the 203 youth players surveyed 26% reported a prior injury to their throwing arm while 23% reported an injury that was concerned with overuse. 11% of players claimed to be currently playing with some sort of arm pain or discomfort. 26% of players stated that they were not having any arm pain.
Other statistics that stood out were 80% of players described having some sort of pain the day after throwing and 82% described having arm fatigue during a game or practice.
54% of players responded that arm pain at some point limited the number of innings they could play and 74% said pain limited how hard they could throw. Interestingly enough 71% did not believe that arm pain limited the number of leagues or teams they could participate in.
The Curveball as a Risk Factor for Injury: A Systematic Review
Authors: Grantham, W. Jeffery; Iyengar, Jaicharan J.; Byram, Ian R.; Ahmad, Christopher S.
The researchers aimed to review the current literature on the risk of throwing curveballs at a young age to see if it increases injury risk or not. 10 biomechanical studies and 6 epidemiologic studies were included in the analysis.
In the epidemiologic studies, the results were somewhat mixed but ⅗ found no association of arm injury/pain and throwing a curveball. All 5 studies suggested that increased amount of innings pitched as a significant risk factor related to arm pain.
Of the biomechanical studies none found increased force or torque at the glenohumeral joint when comparing throwing a curveball versus a fastball. There were differences found within forearm supination, greater supination was found in curveballs along with decreased pronator teres activation. Training supination should be included in youth practices, which is easiest to do in constraint drills.
“Youth pitchers with the highest pitch counts are likely the better pitchers on the team and therefore more inclined to throw a curveball earlier in their careers, further emphasizing overuse as a confounding variable.”
There is limited scientific support in this review to the belief that curveballs lead to injuries more often when compared to a fastball.
A Biomechanical Comparison of Youth Baseball Pitches: Is the Curveball Potentially Harmful?
Authors: Dun, Shouchen; Loftice, Jeremy; Fleisig, Glenn; Kingsley, David; Andrews, James
This study wanted to look just at youth pitchers and examine whether there was a difference in biomechanics between 5 fastballs, curveballs and changeups.
The fastball produced the highest elbow varus torque, shoulder internal rotation torque, elbow proximal force and shoulder proximal force. The curveball was the next highest and the changeup was the lowest. Wrist flexion torque and forearm supination torque were unsurprisingly highest for the curveball compared to a fastball or changeup.
These finding suggest that kinematic and temporal differences were found between all three pitch types but the data doesn’t not support the hypothesis that the curveball is potentially more harmful than the fastball.