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Updated: May 5, 2026

Measurement of Dynamic Scapular Kinematics Using an Acromion Marker Cluster to Minimize Skin Movement Artifact
Published on: February 10, 2015
Effect of the spacing of backpack shoulder straps on cervical muscle activity, acromion and scapular position, and
1Institute of Health Science, Yonsei University.
Abstract:
[Purpose] This study investigated the effect of the spacing of backpack shoulder straps on cervical muscle activity, acromion and scapular position, and upper trapezius (UT) pain. [Subjects] Fourteen males aged 20-32 years, were recruited. [Methods] We measured the MPS (midcervical paraspinal) activity, acromial angle, scapular distance, and UT pain after gait carrying a backpack with different shoulder strap spacings. [Results] The MPS, scapular inferior distance, and UT pressure pain threshold was significantly decreased and the acromion angle was significantly increased when carrying a backpack with wide shoulder straps compared to narrow shoulder straps. [Conclusion] A backpack with wide shoulder straps may cause scapular depression syndrome and chronic UT pain.
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