Shoulder Dislocation in Emergency Medicine Differential Diagnoses

Updated: Sep 04, 2016
  • Author: Sharon R Wilson, MD; Chief Editor: Trevor John Mills, MD, MPH  more...
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DDx

Diagnostic Considerations

Associated fractures occur in approximately 30% of shoulder dislocations. The most common fractures include the Hill Sachs lesion, which is a compression fracture that results in the formation of a groove in the posterolateral aspect of the humeral head. This lesion is seen in 54-76% of dislocations. The Bankart lesion is a fracture of the anterior rim of the glenoid fossa. This lesion results from impaction of the humeral head against the anteroinferior glenoid labrum. It is associated with rupture of the joint capsule and inferior glenohumeral ligament injury. Avulsion fractures of the greater tuberosity are seen in 10-16% of cases. Humeral shaft and coracoid process fractures are rare. (See Complications.)

The rotator cuff is injured in 35-86% of dislocations and is more commonly seen in elderly patients. Glenohumeral ligament injury occurs in approximately 55% of cases and is most common in young patients. The axillary nerve is injured in 3% of anteroinferior dislocations. It is the most frequently injured, but brachial plexus, radial, and other nerve injury can occur. (See Complications.)

If a brachial plexus injury is diagnosed, axillary artery injury, although rare, should be considered. Patients with axillary artery rupture present with axillary hematoma, a cool limb, and absent pulses. However, patients with collateral blood flow may have distal pulses. Luxatio erecta has the highest incidence (3.3%) of vascular compromise. Evaluation of vascular injury should include Doppler blood flow studies, angiography, and arteriography. (See Complications.)

Differential Diagnoses