Movement at any one of these 3 articulations may produce Black Label No movement in other segments as they are all interconnected. Unfortunately, any shortening of a muscle group may cause restricted range of motion in the whole shoulder complex.As you do shoulder exercises the muscles act in combination to produce motion. For instance, the combined motion of the scapula and humerus is called scapulohumeral rhythm and is necessary for the arm to achieve 180 degrees of elevation.The first 30 degrees of abduction is accomplished by the humerus alone, then the scapula joins in to about 120 degrees, and finally the clavicle (collarbone) participates in the remaining 60 degrees of elevation.

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