Posterior shoulder dislocation

Revision as of 00:17, 22 February 2016 by Kxl328 (talk | contribs)


  • Accounts for 2-4% of shoulder dislocations[1]
  • MOI - forceful internal rotation/adduction (2/2 e.g. seizure, electric shock) or blow to ant shoulder
  • Neurovascular and rotator cuff tears are less common than in ant dislocations

Clinical Features

  • Prominence of posterior shoulder and ant flattening of normal shoulder contour
  • Pt unable to rotate or abduct affected arm

Differential Diagnosis

Shoulder and Upper Arm Diagnoses



Refered pain & non-orthopedic causes:


  • Plain film X-ray
    • Scapular "Y" view shows humeral head in posterior position
    • Lack of normal overlap of humeral head and glenoid fossa
    • "Light bulb sign" - fixed internal rotation makes for light bulb appearance of humeral head on AP


  • Reduce
    • Consider procedural sedation
    • Traction applied to adducted arm in long axis of humerus
    • Assistant pushes humeral head anteriorly into glenoid fossa
  • Post-reduction X-ray
  • Apply sling


Posterior dislocation and luxatio erecta.jpg

File:Posterior dislocation and luxatio erecta|thumbnail|Posterior Dislocation Reduction,]]


  • Discharge after reduction
  • Ortho follow-up

See Also


  1. Grate I Jr. Luxatio erecta: a rarely seen, but often missed shoulder dislocation. Am J Emerg Med. 2000 May;18(3):317-21.