Rotator Cuff Impingement

The rotator cuff cuff is a group of four muscles and their respective tendons that help to control the elevation and rotation of the shoulder.  It is called a “cuff” because three of the four tendons attach to the humerus (ball of the shoulder) with the appearance of a single attachment.  The rotator cuff tendons can become inflamed after repetitive overhead activities.  If the tendon rubs on the bone and ligament above it during overhead activities, this is called impingement.  Chronic impingement can lead to tearing of the tendon.  For some patients, bone can form a “spur” above the rotator cuff and this can cause the impingement. The “spur” can be thought of as like a metal can opener, which digs into the tendon as the arm is placed overhead.

Large acromial spur from the undersurface of the acromion

How it presents

Patients often complain of pain along the anterior and lateral aspect of the shoulder, which classically is worse when lying in bed at night. 


Physical therapy can improve pain, motion, and function in most patients that do not have a signficant tear. Injections of a corticosteroid and use of anti-inflammatory medications. For those with chronic symptoms not responsive to conservative treatment, arthroscopic surgery to remove scar, inflamed tissue, and impinging bone can be curative.

Watch a video of a shoulder arthroscopy with subacromial decompression