The Clinician's Guide to Baseball Pitching Biomechanics

Context: Improper baseball pitching biomechanics are associated with increased stresses on the throwing elbow and shoulder as well as an increased risk of injury. Evidence Acquisition: Previous studies quantifying pitching kinematics and kinetics were reviewed. Study Design: Clinical review. Level of Evidence: Level 5. Results: At the instant of lead foot contact, the elbow should be flexed approximately 90 degrees with the shoulder at about 90 degrees abduction, 20 degrees horizontal abduction, and 45 degrees external rotation. The stride length should be about 85% of the pitcher's height with the lead foot in a slightly closed position. The pelvis should be rotated slightly open toward home plate with the upper torso in line with the pitching direction. Improper shoulder external rotation at foot contact is associated with increased elbow and shoulder torques and forces and may be corrected by changing the stride length and/or arm path. From foot contact to maximum shoulder external rotation to ball release, the pitcher should demonstrate a kinematic chain of lead knee extension, pelvis rotation, upper trunk rotation, elbow extension, and shoulder internal rotation. The lead knee should be flexed about 45 degrees at foot contact and 30 degrees at ball release. Corrective strategies for insufficient knee extension may involve technical issues (stride length, lead foot position, lead foot orientation) and/or strength and conditioning of the lower body. Improper pelvis and upper trunk rotation often indicate the need for core strength and flexibility. Maximum shoulder external rotation should be about 170 degrees. Insufficient external rotation leads to low shoulder internal rotation velocity and low ball velocity. Deviation from 90 degrees abduction decreases the ability to achieve maximum external rotation, increases elbow torque, and decreases the dynamic stability in the glenohumeral joint. Conclusion: Improved pitching biomechanics can increase performance and reduce risk of injury. SORT: Level C.

Automated summary

Improper baseball pitching biomechanics can increase stresses on the throwing elbow and shoulder, leading to a higher risk of injury. Correct pitching mechanics involve specific angles and external rotation of the elbow and shoulder, appropriate stride length and position, and a smooth kinematic chain. Improving pitching biomechanics can enhance performance and reduce injury risk.