There are several muscles of different shapes and sizes in the upper back, which help with neck, shoulder, and arm movements. Injuries to these muscles can cause upper back pain. The feeling can ...

"When there is a weakness or an imbalance in this group of muscles it can lead to shoulder impingement syndrome or a loss of ...

Finally the arm, elbow, and wrist act as a force delivery mechanism. Breakage of a link in the proximal part of the ... tightness at the anterior side of the shoulder (inflexibility of the pectoralis ...

the shoulder is in a position of maximal external rotation while the internal rotator muscles act on the proximal aspect of the humerus. The distal humerus and forearm lag behind the elbow, placing ...