Introduction
Impingement syndrome is a common condition affecting the shoulder often seen in aging adults. This condition is closely related to shoulder bursitis and rotator cuff tendonitis. These conditions may occur alone or in combination.
In virtually all parts of your body, bones are the innermost structures and are surrounded by muscles. When an injury occurs to the rotator cuff muscles, they respond by swelling. However, because the rotator cuff muscles are surrounded by bone, when they swell, a series of other events occur.
The pressure within the muscles increases, which results in compression and loss of blood flow in the small blood vessels. When the blood flow decreases, the muscle tissue begins to fray like a rope. Motions such as reaching up behind the back and reaching up overhead to put on a coat or blouse, for example, may cause pain.
What Are the Symptoms of Shoulder Impingement Syndrome?
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 these muscles are injured for a long period of time, the muscle 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 will have rupture of their biceps muscle as part of this continuing impingement process.
How Is Impingement Syndrome Diagnosed?
Diagnosis begins with a medical history and physical examination by your doctor. X-rays will be taken to rule out arthritis and may show changes in the bone that indicate injury of the muscle. Bone spurs or changes in the normal contour of the bone may be present. Impingement syndrome may be confirmed when an injection of a small amount of an anesthetic into the space under one of the shoulder bones relieves pain.
How Is Shoulder Impingement Syndrome Treated?
It is important to understand that the condition and not just the symptoms require treatment. Oral anti-inflammatory medications ?such as aspirin, naproxen or ibuprofen, remain the most common treatment for this condition.
You must consistently take the medication for nearly eight weeks for it to be effective. Taking anti-inflammatory medications for a short period of time may treat the symptom of pain, but it will not treat the underlying problem and symptoms will come back. There is no specific medication for this condition and response to any given medication differs from person to person. If one anti-inflammatory medication does not help within 10 to 14 days, then another one will be given until one that provides relief is found.
In addition to taking medications, daily stretching in a warm shower will help. Work to reach your thumb up and behind your back. Avoid repetitive activities with your injured arm, particularly where the elbow would move above shoulder level. Avoid vacuuming, painting, raking leaves and washing the car.
If you have persistent symptoms, despite the use of oral anti-inflammatory medications, your doctor may consider a cortisone-type injection. Cortisone is a potent anti-inflammatory medication, which should be used only when necessary because it can result in weakening of muscles and tendons.
If symptoms persist or if significant weakness is present, then your doctor may perform an MRI or arthrogram to rule out a rotator cuff tear. If the cuff is torn, surgery may be necessary to repair it.
The vast majority of people who have impingement syndrome are successfully treated with medication, stretching exercises and temporary avoidance of repetitive overhead activity until the condition settles down.
What Side Effects are Associated With Treatment?
Upset stomach, indigestion and headaches are the most common side effects of oral anti-inflammatory medications. However, taking these medications after meals or with food can help reduce stomach upset. Anti-inflammatory medicines also can cause vomiting, constipation and bleeding in the stomach (ulcers), although these side effects are not common.
Side effects of cortisone shots depend on the dose and frequency of the injections. Unlike cortisone pills, occasional cortisone injections rarely cause serious side effects. However, possible side effects of cortisone include elevated blood sugar, a decrease in the body's resistance to infection, weight gain, osteoporosis (thinning of the bones), thinning of the skin and raised blood pressure.
Reviewed by the doctors at The Cleveland Clinic Department of Rheumatic and Immunologic Diseases.
Edited by Michael W. Smith, MD, Sept. 2003.
Portions of this page © The Cleveland Clinic 2000-2003.