The sternoclavicular, manubriosternal and sternocostal joints are important for the biomechanics of the chest during respiration. This implies a nearly constant strain on the joints, which may result in degenerative changes. In addition, the sternoclavicular joints accompany every movement of the arms being the only joints between the trunk and the upper extremities.
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和呼吸很有關係，和手部上肢的運動也很有關連 ( esp SC joints accompany every movement of the arms)，若要沉肩，這個關係也非注意不可。
