Shoulder dislocation (summary)

This is a basic article for medical students and other non-radiologists

Shoulder dislocation is defined as the humeral head moving out of the glenoid fossa. It is almost always traumatic in etiology.

Reference article

This is a summary article. For more information, you can read a more in-depth reference article: shoulder dislocation.

Summary

  • anatomy
  • epidemiology
    • most commonly dislocated joint
    • bimodal age and sex distribution
    • male:female 9:1 in younger population (20-30 years)
  • presentation
    • shoulder pain
    • reduced range of motion
  • pathophysiology
    • almost always traumatic
    • 95% of dislocations are anterior
  • investigation
    • x-ray for diagnosis and follow-up
    • CT for assessment of associated complex fractures
    • MRI (not acute) in shoulder instability or labrum injury
  • treatment
    • prompt reduction with anesthesia

Radiographic features

Plain radiograph

Frontal and Y-views are performed for the assessment of shoulder injury and shoulder dislocation.

The vast majority of shoulder dislocations are anterior. The humeral head overlies the glenoid and moves medially. On the Y-view, the humeral head is clearly demonstrated anterior to the glenoid fossa.

Look carefully for evidence of other injuries, e.g. fractures of the humeral head or neck, or the clavicle.

Medical student radiology curriculum