Shoulder impingement a common overuse injury among athletes

  • June 2004 Rehab Review

    On occasion, soccer players and other athletes suffer shoulder injuries. One such condition is known as a shoulder impingement.

    What is shoulder impingement?
    Impingement refers to mechanical compression and/or wear of an athlete's rotator cuff tendons. The rotator cuff is actually a series of four muscles connecting the scapula (shoulder blade) to the humeral head (upper part of the shoulder joint). The rotator cuff is important in maintaining the humeral head within the glenoid (socket) during normal shoulder function and also contributes to shoulder strength during activity. Normally, the rotator cuff glides smoothly between the undersurface of the acromion (point of the shoulder) and the humeral head.

    Causes of shoulder impingement
    Any process which compromises this normal gliding function may lead to mechanical impingement. Common causes include weakening and degeneration within the tendon due to aging, the formation of bone spurs and/or inflammatory tissue within the space above the rotator cuff (subacromial space) and overuse injuries.

    Diagnosing shoulder impingement
    The diagnosis of shoulder impingement can usually be made with a careful history and physical exam. Athletes with impingement most commonly complain of pain in the shoulder, which is worse with overhead activity and sometimes severe enough to cause awakening in the night. Having your physician manipulate the shoulder in a specific way will usually reproduce the symptoms and confirm the diagnosis. X-rays are helpful to evaluate the presence of bone spurs and/or the narrowing of the subacromial space. MRI (magnetic resonance imaging), a test that allows visualization of the rotator cuff, is usually not necessary in cases of shoulder impingement, but may be used to rule out more serious diagnoses.

    Treatment options
    The first step in treating shoulder impingement is to eliminate any identifiable cause or contributing factor. Athletes may need to temporarily avoid activities that involve repetitive shoulder movement. Your physician also may recommend a non-steroidal anti-inflammatory medication. The mainstay of treatment involves exercises to restore normal flexibility and strength to the shoulder girdle, including strengthening both the rotator cuff muscles and the muscles responsible for normal shoulder blade movement. This program of instruction and exercise demonstration may be initiated and carried out by a physician, certified athletic trainer or a skilled physical therapist. Occasionally, an injection of cortisone may be helpful in treating this condition.

    Is surgery necessary?
    Surgery is not necessary in most cases of shoulder impingement. However, if an athlete's symptoms persist despite adequate non-surgical treatment, surgical intervention may be beneficial. Surgery involves debriding, or surgically removing tissue that is irritating the rotator cuff. This procedure may be conducted with either open or arthroscopic techniques. The outcome is favorable in about 90 percent of the cases.