Document Type

Article

Peer Reviewed

1

Publication Date

8-1996

Journal/Book/Conference Title

Journal of Orthopaedic & Sports Physical Therapy

DOI of Published Version

10.2519/jospt.1996.24.2.57

Abstract

Abnormal scapular kinematics and associated muscle function presumably contribute to shoulder pain and pathology. An understanding of scapular kinematic and electromyographic profiles in asymptomatic individuals can provide a basis for evaluation of pathology. The purpose of this study was to describe normal 3-dimensional scapular orientation and associated muscle activity during humeral elevation. Twenty-five asymptomatic subjects, 19-37 years old, were evaluated. Digitized coordinate data and surface electromyographic signals from the trapezius (upper and lower), levator scapulae, and serratus anterior were collected at static positions of 0°, 90°, and 140° of humeral elevation in the scapular plane. The scapula demonstrated a pattern of progressive upward rotation, decreased internal rotation, and movement from an anteriorly to a posteriorly tipped position as humeral elevation angle increased. Electromyographic activity of all muscles studied increased with increased humeral elevation angles. Differences between mean values at all elevation angles for all variables were significant (p < .05), except for the lower trapezius between the 90° and 140° humeral angles. The results of this study suggest assessment of scapular tipping and internal rotation as well as upward rotation may be necessary to understand pathologies of the shoulder that are related to abnormal scapular kinematics.

Keywords

sustainability, scapula, electromyography, shoulder joint

Journal Article Version

Version of Record

Published Article/Book Citation

Journal of Orthopaedic & Sports Physical Therapy, 24:2 (1996) pp.57-65. DOI:10.2519/jospt.1996.24.2.57.

Rights

Copyright © JOSPT and the Orthopaedic and Sports Physical Therapy Sections of the American Physical Therapy Association. Posted by permission.

Share

COinS
 

URL

https://ir.uiowa.edu/oeh_pubs/180