Shoulder impingement syndrome generally happens gradually – caused by the compression of the tendons of the rotator cuff, between part of the shoulder blade and the head of the humerus. The result is pain, weakness and loss of motion, as well as the potential for other conditions such as bursitis, and rotator cuff tendonitis and tears.
The compression, or impingement, may be prompted by a number of factors – acromioclavicular (AC) joint arthritis, calcification, structural abnormalities of the acromion, and overstressed and weakened rotator cuff muscles.
Those suffering from an impingement are usually prompted to seek medical consultation once night pain begins preventing comfortable sleep. Progressively symptoms become more prominent and range of motion greatly reduced.
Those at Risk
Shoulder impingement can affect the young athlete involved in overhead sports and older adult with a history of shoulder pain and stress alike.
Impingement syndrome can be generally classified into stages. Stage I is often associated with overuse injuries and includes edema and/or hemorrhage – most often occurring in patients under the age of 24. Stage II is more advanced and occurs most often in patients between the ages of 25 and 40. Fibrosis and more severe tendon changes are evident in Stage II. Stage III is found most often in patients over the age of 50 and involves a tendon rupture or tear – most likely the result of long-term vulnerability and corresponding degeneration.
Patient history and pain analysis are first assessed when determining a diagnosis. A physical examination noting signs of impingement during passive shoulder motion are also important in determining if a patient suffers from shoulder impingement.
Depending on patient history, radiographic testing may be indicated in order to rule out other conditions and clearly identify tissue changes. And when a rotator cuff tear is suspected, magnetic resonance imaging by also be indicated.
Conservative nonsurgical treatment is effective in addressing many impingement conditions, particularly in the early stages. These may include; cold compression to reduce swelling, nonsteroidal anti-inflammatory drugs (NSAIDs), a period of rest and refrain from activity that aggravates the condition, and a rehabilitative exercise program designed to strengthen shoulder muscles.
Injection therapy including lidocaine and corticosteroid may be recommended when impingement does not improve with initial conservative treatment. This is determined based on the age, condition and activity level of each patient.
When conservative treatment does not improve the condition, arthroscopic surgery may be indicated in order to facilitate decompression.