What is a Shoulder Impingement Syndrome (Swimmer’s Shoulder)? The shoulder is made up of the humerus (upper arm bone), the scapula (shoulder blade), and the clavicle (collarbone). The location above the head of the humerus is known as the subacromial space (below the acromion of the scapula). This space is normally a very narrow space that houses the tendons of the rotator cuff and the subacromial bursa (a fluid filled sac for lubrication). When the shoulder is elevated (flexed up to raise the arm) or internally rotated this space becomes narrower, causing an impingement. Causes Strong internal rotator muscles and weakness of the periscapular muscles (muscles around the scapula) Overuse without proper rest Drastic changes in training routine Unequal shoulder flexibility compared to the other side Signs & Symptoms Shoulder pain with raising the arm Worsening pain with increased activity Soreness or aching following activity or at night Decreased range of motion due to pain Treatment Initial treatment of a shoulder impingement syndrome is rest from all aggravating activities. After the pain subsides, beginning physical therapy to regain motion and strength gradually is common. Strengthening of the periscapular muscles and stretching of the internal rotator and pectoralis muscles is commonly where physical therapy is directed to help regain normal motion of the humerus within the glenoid (the socket of the shoulder joint). If pain continues or worsens after following the non-surgical course of physical therapy, surgery may be warranted.