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Differences in scapular upward rotation between baseball pitchers and position players
Kevin G Laudner1, Justin M Stanek, Keith Meister
1Biomechanics Laboratory, School of Kinesiology and Recreation, Illinois State University, Normal, Illinois 61790, USA. klaudner@ilstu.edu
The American Journal of Sports Medicine
|August 10, 2007
Summary
Baseball pitchers exhibit reduced scapular upward rotation compared to position players, potentially increasing shoulder injury risk. Targeted exercises may help improve this motion for pitchers.
Area of Science:
- Sports Medicine
- Biomechanics
- Orthopedics
Background:
- Baseball pitchers have a higher incidence of shoulder injuries than position players.
- Limited scapular upward rotation is associated with shoulder disorders.
Purpose of the Study:
- To compare scapular upward rotation between professional baseball pitchers and position players.
Main Methods:
- A descriptive laboratory study was conducted.
- Scapular upward rotation was measured in 15 pitchers and 15 position players.
- Measurements were taken at rest and at 60, 90, and 120 degrees of humeral elevation.
Main Results:
- Pitchers demonstrated significantly less scapular upward rotation than position players.
- This difference was noted at 60 degrees (3.9 degrees) and 90 degrees (4.4 degrees) of humeral elevation.
Conclusions:
- Baseball pitchers have decreased scapular upward rotation, particularly at 60 and 90 degrees of humeral elevation.
- This deficit may elevate injury risk; periscapular exercises could be beneficial for pitchers.
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