Effect of the Spacing of Backpack Shoulder Straps on Cervical Muscle Activity, Acromion and Scapular Position, and Upper Trapezius Pain

摘要

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.Fourteen males aged 20-32 years, were recruited. We measured the MPS (midcervical paraspinal) activity, acromial angle, scapular distance, and UT pain after gait carrying a backpack with different shoulder strap spacings. 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.A backpack with wide shoulder straps may cause scapular depression syndrome and chronic UT pain.