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Updated: Aug 9, 2026

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Patterns of shoulder flexibility among college baseball players
Abstract:
In this study, I investigated and analyzed the various joint motions in the shoulders of college baseball players. Twenty-six players (age=20.38+/-1.36 yr) from two colleges were examined for upper extremity range of motion (ROM), including shoulder flexion, extension, internal rotation at 90 degrees abduction, and external rotation at 90 degrees abduction. Joint motions were measured using a JAMAR(R), six-inch, double-arm goniometer. Pitchers demonstrated 22 degrees more shoulder flexion and 21 degrees more external rotation at 90 degrees abduction than infield position players, and 17 degrees more shoulder flexion than outfield position players. There was no significant difference between the dominant arm flexibility of infield and outfield position players. When comparing the dominant to nondominant arm relative to the position, infield position players demonstrated 5 degrees less shoulder flexion and 6 degrees more external rotation on the dominant side at 90 degrees abduction. Pitchers did not demonstrate any significant difference between the dominant and nondominant arm. There was, however, an indication that pitchers had a tendency to exhibit greater flexibility during flexion and external rotation at 90 degrees abduction in the dominant side than in the nondominant side.
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