Rotator Cuff Impingement
Shoulder impingement syndrome occurs when the tendons of the rotator cuff and the subacromial bursa are pinched in the narrow space beneath the acromion. This causes the tendons and bursa to become inflamed and swollen. This pinching is worse when the arm is raised away from the side of the body. Impingement may develop over time as a result of a minor injury, or as a result of repetitive motions that lead to inflammation in the bursa.