The painful shoulder: part II. Acute and chronic disorders.

Fractures of the humerus, scapula and clavicle usually result from a direct blow or a fall onto an outstretched hand. Most can be treated by immobilization. Dislocation of the humerus, strain or sprain of the acromioclavicular and sternoclavicular joints, and rotator cuff injury often can be managed conservatively. Recurrence is a problem with humerus dislocation, and surgical management may be indicated if conservative treatment fails. Rotator cuff tears are often hard to diagnose because of muscle atrophy that impairs the patient's ability to perform diagnostic maneuvers. Chronic shoulder problems usually fall into one of several categories, which include impingement syndrome, frozen shoulder and biceps tendonitis. Other causes of chronic shoulder pain are labral injury, osteoarthritis of the glenohumeral or acromioclavicular joint and, rarely, osteolysis of the distal clavicle.