The rotator cuff is made up of four muscles (supraspinatus, infraspinatus, subscapularis, and teres minor) and their tendons. It provides stability and strength for the shoulder joint, anchoring the humerus (upper arm bone) to the scapula (shoulder blade) so that movements of the arm can occur in a smooth and coordinated fashion.
Shoulder pain may be caused by inflammation or injury to the rotator cuff tendons resulting from trauma, overuse, weakness, poor posture, or a faulty movement pattern. In the early stages pain may be caused by “impingement syndrome”. The rotator cuff can become irritated or inflamed when it becomes pinched between the acromion (the roof portion of the shoulder) and the humeral head (the ball portion of the shoulder joint). Some common causes of impingement syndrome are repetitive throwing, lifting, or overhead activities such as painting. Impingement syndrome may cause shoulder aching or sharp pain when trying to reach behind your back.