Wind up and deliver: Proper pitching biomechanics reduce injury risk

To reduce injury risk and enhance their performance, baseball pitchers need to learn proper fastball mechanics at an early age, according to Dave Fortenbaugh, Glenn S. Fleisig, PhD, and James R. Andrews, MD, at the American Sports Medicine Institute in Birmingham, Alabama. They recommend that young pitchers use a change-up as a safe secondary pitch to complement the fastball, add a curveball after fastball and change-up mechanics are mastered, and avoid overuse and pitching when they are fatigued to minimize the risk of arm injury. Their article "Baseball pitching biomechanics in relation to injury risk and performance" appeared in a recent issue of Sports Health.

Knowledge of the mechanics that can improve performance and prevent injury is an invaluable resource for physicians, athletic trainers, therapists, coaches, and athletes, the authors stated. To acquire evidence, they searched PubMed and SportDiscus for original studies published between 1994 and 2008 and retrieved relevant references. Included were studies that tested relationships between kinematics and kinetics and between kinematics and ball velocity.

The authors found that kinematic parameters at the instant of foot contact-front foot position, front foot orientation, shoulder abduction, and shoulder horizontal adduction-are associated with increased upper extremity kinetics. Factors associated with increased kinetics and decreased ball velocity include the timing of shoulder external rotation, pelvis rotation, and upper trunk rotation. Also associated with decreased ball velocity are low braking force of the lead leg, a short stride, decreased maximum shoulder external rotation, shoulder abduction, knee extension, and trunk tilt.

As pitchers develop, the authors noted, kinematic values remain similar but have less variability and kinetic values gradually increase. There are slight kinematic variations among pitch types. Kinetic values remain constant as pitchers fatigue, but increases in arm pain are reported.