Throwing arm dominance in collegiate baseball pitching: a biomechanical study

Area of Science:

• Sports Biomechanics
• Baseball Pitching Analysis
• Orthopedic Sports Medicine

Background:

• Left-handed pitchers are disproportionately represented in baseball.
• Previous research has not detailed biomechanical differences between left- and right-handed pitchers.

Purpose of the Study:

• To compare pitching mechanics and upper extremity joint loads between left- and right-handed pitchers.
• To identify biomechanical distinctions that may influence injury risk.

Main Methods:

• Controlled laboratory study involving 84 collegiate baseball pitchers.
• Three-dimensional, high-speed video analysis of fastball pitching.
• Matched-pair analysis comparing 28 left-handed and 28 right-handed pitchers on kinematic and kinetic parameters.

Main Results:

• Significant differences observed in six parameters between left- and right-handed pitchers.
• Left-handed pitchers showed greater passive nonthrowing shoulder external rotation, elbow flexion at stride-foot contact, and shoulder abduction during acceleration.
• Left-handed pitchers exhibited less shoulder abduction at stride-foot contact, less shoulder horizontal abduction at stride-foot contact, and lower peak horizontal adduction angular velocity.

Conclusions:

• Biomechanical differences between left- and right-handed pitchers are evident in collegiate baseball.
• Left-handed pitchers may face a higher risk of specific shoulder injuries.
• Development of separate normative data sets for left- and right-handed pitchers is recommended.