Abstract：
UNASSIGNED: The normal value of the scapular muscle activity ratio during arm elevation is not clear.
UNASSIGNED: To obtain normal values of the scapular muscle activity ratio during arm elevation in healthy individuals.
UNASSIGNED: This cross-sectional study enrolled 47 healthy people. The participants performed shoulder flexion and lowered task with 90-degree movements every 2 seconds. Muscle activities of scapular muscles were measured. For normalization, the maximum isometric contraction of the shoulder flexion was measured at 90∘ (reference contraction). The integrated electromyographic value (IEMG) obtained during the task was normalized by IEMG during the reference contraction and the relative IEMG value was calculated. Then, the scapular muscle activity ratio was computed. The relationship between muscle strength and other factors was also investigated.
UNASSIGNED: The median values for upper trapezius/serratus anterior and upper trapezius/lower trapezius were often approximately 1, and that for upper trapezius/middle trapezius was often between 1 and 2. The shoulder flexion isometric strength and scapular muscle activity ratio showed significant negative correlations in multiple phases.
UNASSIGNED: Normal values for upper trapezius/serratus anterior and upper trapezius/lower trapezius during arm elevation and lowering were generally 1. Low muscle strength may contribute to an abnormal scapular muscle activity balance.
UNASSIGNED: To obtain normal values of the scapular muscle activity ratio during arm elevation in healthy individuals.
UNASSIGNED: This cross-sectional study enrolled 47 healthy people. The participants performed shoulder flexion and lowered task with 90-degree movements every 2 seconds. Muscle activities of scapular muscles were measured. For normalization, the maximum isometric contraction of the shoulder flexion was measured at 90∘ (reference contraction). The integrated electromyographic value (IEMG) obtained during the task was normalized by IEMG during the reference contraction and the relative IEMG value was calculated. Then, the scapular muscle activity ratio was computed. The relationship between muscle strength and other factors was also investigated.
UNASSIGNED: The median values for upper trapezius/serratus anterior and upper trapezius/lower trapezius were often approximately 1, and that for upper trapezius/middle trapezius was often between 1 and 2. The shoulder flexion isometric strength and scapular muscle activity ratio showed significant negative correlations in multiple phases.
UNASSIGNED: Normal values for upper trapezius/serratus anterior and upper trapezius/lower trapezius during arm elevation and lowering were generally 1. Low muscle strength may contribute to an abnormal scapular muscle activity balance.
摘要：
背景：手臂抬高期间肩胛骨肌肉活动比的正常值尚不清楚。
目的：获得健康人手臂抬高过程中肩胛骨肌肉活动比的正常值。
方法：这项横断面研究纳入了47名健康人。参与者每2秒进行90度运动，进行肩部屈曲和降低任务。测量肩胛骨肌肉的肌肉活动。对于规范化，肩部屈曲的最大等距收缩在90°（参考收缩）处测量。在参考收缩期间，通过IEMG对任务期间获得的积分肌电图值（IEMG）进行归一化，并计算出相对IEMG值。然后，计算肩胛骨肌肉活动比率。还研究了肌肉力量与其他因素之间的关系。
结果：上斜方肌/前斜方肌和上斜方肌/下斜方肌的中值通常约为1，上斜方肌/中斜方肌的中值通常在1和2之间。肩屈等轴力与肩胛骨肌肉活动比在多个阶段呈显著负相关。
结论：上斜方肌/前斜方肌和上斜方肌/下斜方肌在上臂升高和降低期间的正常值一般为1。肌肉力量不足可能导致肩胛骨肌肉活动平衡异常。
目的：获得健康人手臂抬高过程中肩胛骨肌肉活动比的正常值。
方法：这项横断面研究纳入了47名健康人。参与者每2秒进行90度运动，进行肩部屈曲和降低任务。测量肩胛骨肌肉的肌肉活动。对于规范化，肩部屈曲的最大等距收缩在90°（参考收缩）处测量。在参考收缩期间，通过IEMG对任务期间获得的积分肌电图值（IEMG）进行归一化，并计算出相对IEMG值。然后，计算肩胛骨肌肉活动比率。还研究了肌肉力量与其他因素之间的关系。
结果：上斜方肌/前斜方肌和上斜方肌/下斜方肌的中值通常约为1，上斜方肌/中斜方肌的中值通常在1和2之间。肩屈等轴力与肩胛骨肌肉活动比在多个阶段呈显著负相关。
结论：上斜方肌/前斜方肌和上斜方肌/下斜方肌在上臂升高和降低期间的正常值一般为1。肌肉力量不足可能导致肩胛骨肌肉活动平衡异常。
