ImpingementSyndromen

ImpingementSyndromen is a common cause of shoulder pain characterized by compression of the rotator cuff tendons and the subacromial bursa as the arm is raised, typically in overhead activities. The condition can involve degenerative changes in the tendons, bursitis, and narrowing of the subacromial space. It is often discussed as a spectrum that includes primary or mechanical impingement as well as secondary impingement due to dynamic shoulder instability.

The condition is generally categorized as primary impingement, caused by structural factors such as an enlarged or hooked acromion, osteophytes, or have an inherently reduced subacromial space. Secondary impingement results from altered shoulder mechanics, such as rotator cuff tendinopathy, scapular dyskinesis, or glenohumeral instability, leading to impingement during motion. Internal impingement, seen in athletes who perform extreme throwing or overhead motions, involves contact of the posterior cuff against the glenoid rim in abduction and external rotation.

Symptoms typically include anterior or lateral shoulder pain that worsens with lifting the arm overhead, decreased strength, and night pain. Pain during overhead activities is common, and there may be tenderness around the subacromial region.

Diagnosis relies on clinical examination and imaging. Physical tests such as Neer and Hawkins-Kennedy provocative maneuvers can suggest impingement. X-ray evaluates bony etiologies; MRI or ultrasound assesses rotator cuff integrity and subacromial pathology.

Management is usually nonoperative initially, with activity modification, targeted physical therapy, nonsteroidal anti-inflammatory drugs, and subacromial corticosteroid injections. If symptoms persist, surgical options include arthroscopic subacromial decompression or acromioplasty, with repair of any coexisting rotator cuff tear. Prognosis varies with severity and underlying pathology, but many patients improve with conservative treatment.