The rotator cuff is a group of muscles and tendons that stabilizes the shoulder joint. Rotator cuff tears are common orthopedic injuries often resulting from falls, lifting heavy objects and repetitive arm motion. If you are experiencing pain or tenderness when raising your arm laterally, you might require additional treatment for your rotator cuff injury.
Rotator Cuff
The rotator cuff is composed of four muscles, each connecting the upper arm bone, or humerus, to the shoulder blade, or scapula. The function of these muscles depends entirely on where they insert their tendons into the humerus and scapula. For instance, the supraspinatus muscle originates on the upper part of the scapula and inserts on the outside of the humerus. When this muscle contracts, the arm is raised laterally. Pain with this type of motion is highly indicative of a problem in the supraspinatus muscle or tendon.
Supraspinatus Muscle and Tendon
According to Harrison's Internal Medicine, rotator cuff pain often is caused by inflammation of the supraspinatus tendon. The tendonitis seen in these cases typically is caused by impingement of the tendon between several bones in the shoulder joint. When the arm is raised laterally, the tendon become trapped between these bones, often reducing blood supply and causing further damage and pain.
Impingement Syndrome and Tendonitis
Symptoms of impingement commonly present after injury or overuse. Baseball, tennis, swimming and any activity requiring you to repeatedly elevate your arm are prone to produce this syndrome. It is common to experience a dull aching in the shoulder, with severe pain when raising the arm laterally and into an overhead position. This condition can be managed conservatively with NSAIDs, glucocorticoid injection and physical therapy. If improvement is not seen, surgery might be required to decompress the inflamed tendon. According to MayoClinic.com, untreated inflammation can lead to tendon weakening and degeneration. Overuse that produces significant stress on the suprascapular tendon and muscle might lead either structure to tear or strain.
Bursitis
Another important structure in the rotator cuff that can produce pain with lateral movement is the subacromial bursa. This fluid-filled sac normally facilitates movement of the shoulder, serving to cushion the space between bones and muscle of the rotator cuff. The subacromial bursa can become inflamed and irritated with overuse, thus producing symptoms of pain with movement.
References
- "Harrison's Internal Medicine: Rotator Cuff Tendinitis and Impingement Syndrome"; Carol Langford and Bruce Gilliland; 2010
- "Tintinalli's Emergency Medicine: Shoulder Pain"; David Della-Giustina and Benjamin Harrison; 2010
- MayoClinic.com: Rotator Cuff Injury
