Shoulder impingement syndrome is a common cause of shoulder pain. It occurs when there is impingement of tendons or bursa in the shoulder from bones of the shoulder.
Impingement occurs to some degree in everyone’s shoulder. Day-to-day activities that involve using the arm above shoulder level cause some impingement. Usually it doesn’t lead to any prolonged pain. But continuously working with the arms raised overhead (overhead activity of the shoulder), repeated throwing activities, or other repetitive actions of the shoulder can cause impingement to become a problem. Impingement becomes a problem when it causes irritation or damage to the rotator cuff tendons.
Examples for overhead activities, which may lead to shoulder impingement syndrome, include: painting, lifting, swimming, tennis, and other overhead sports. Other risk factors include bone and joint abnormalities.
With impingement syndrome, pain is persistent and affects everyday activities. Motions such as reaching up behind the back or reaching up overhead to put on a coat or blouse, for example, may cause pain.
Over time, impingement syndrome can lead to inflammation of the rotator cuff tendons (tendinitis) and bursa (bursitis). If not treated appropriately, the rotator cuff tendons can start to thin and tear.
The typical symptoms of impingement syndrome include difficulty reaching up behind the back, pain with overhead use of the arm and weakness of shoulder muscles.
If tendons are injured for a long period of time, the tendon can actually tear in two, resulting in a rotator cuff tear. This causes significant weakness and may make it difficult for the person to elevate his or her arm. Some people can have rupture of their biceps muscle as part of this continuing impingement process.