Difference between revisions of "Posterior shoulder dislocation"

(Created page with "==Background== *Via forceful internal rotation/adduction (sz, electric shock) or blow to ant shoulder *Neurovascular and rotator cuff tears are less common than in ant disloca...")
 
 
(23 intermediate revisions by 7 users not shown)
Line 1: Line 1:
 
==Background==
 
==Background==
*Via forceful internal rotation/adduction (sz, electric shock) or blow to ant shoulder
+
*2-4% of shoulder dislocations<ref>Grate I Jr. Luxatio erecta: a rarely seen, but often missed shoulder dislocation. Am J Emerg Med. 2000 May;18(3):317-21.</ref>
*Neurovascular and rotator cuff tears are less common than in ant dislocations
+
*Causes:
 +
**Forceful internal rotation and adduction  
 +
***Usually due to seizure or electric shock
 +
****Consider in alcohol withdrawal, even without clear history of shoulder
 +
**Blow to anterior shoulder
 +
*Complications (neurovascular injuries and rotator cuff tears) less common than in anterior dislocation
 +
*May go undetected for extended period as often missed on physical exam and imaging
  
 
==Clinical Features==
 
==Clinical Features==
*Prominence of posterior shoulder and ant flattening of normal shoulder contour
+
*Posterior aspect of shoulder unusually prominent
*Pt unable to rotate or abduct affected arm
+
*Anterior aspect of shoulder appears flattened
 +
*Inability to rotate or abduct affected arm
  
==Diagnosis==
+
==Differential Diagnosis==
===Imaging===
+
{{Shoulder DDX}}
*Scapular "Y" view shows humeral head in posterior position
+
 
 +
==Evaluation==
 +
[[File:Lightbulb sign - posterior shoulder dislocation - Roe vor und nach Reposition 001.jpg|thumb|Light bulb sign (left) with post-reduction comparison (right)]]
 +
*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
 +
*Bedside ultrasound can be used to assess for both dislocation and successful reduction
 +
 
 +
==Management==
 +
*Closed reduction
 +
**Most require [[procedural sedation]]
 +
#Adduct the arm
 +
#Apply traction along long axis of humerus
 +
#Have assistant push humeral head anteriorly into glenoid fossa
 +
#Apply shoulder immobilizer
 +
#Obtain post-reduction radiographs
 +
*'''Note: Do not reduce chronic dislocations (>4 weeks) in the ED due to risk of arterial injury''' - consult ortho for open reduction
  
==Differential Diagnosis==
+
==Disposition==
 +
*Discharge after successful reduction
 +
*Orthopedic surgery outpatient follow-up
 +
*Any patient with a chronic dislocation requires orthopedic consult in the ED for consideration of operative reduction due to the risk of arterial injury
 +
 
 +
==See Also==
 
*[[Shoulder dislocation]]
 
*[[Shoulder dislocation]]
**[[Anterior shoulder dislocation]]
 
**[[Posterior shoulder dislocation]]
 
**[[Inferior shoulder dislocation]]
 
  
==Management==
+
==External Links==
*Reduce
+
*https://youtu.be/KRCqVekNEKc
**Traction applied to adducted arm in long axis of humerus
 
**Assistant pushes humeral head anteriorly into glenoid fossa
 
*Spling, ortho f/u
 
  
 
==References==
 
==References==
 
<references/>
 
<references/>
  
[[Category:Ortho]]
+
[[Category:Orthopedics]]
 +
[[Category:Procedures]]

Latest revision as of 19:38, 26 September 2019

Background

  • 2-4% of shoulder dislocations[1]
  • Causes:
    • Forceful internal rotation and adduction
      • Usually due to seizure or electric shock
        • Consider in alcohol withdrawal, even without clear history of shoulder
    • Blow to anterior shoulder
  • Complications (neurovascular injuries and rotator cuff tears) less common than in anterior dislocation
  • May go undetected for extended period as often missed on physical exam and imaging

Clinical Features

  • Posterior aspect of shoulder unusually prominent
  • Anterior aspect of shoulder appears flattened
  • Inability to rotate or abduct affected arm

Differential Diagnosis

Shoulder and Upper Arm Diagnoses

Traumatic/Acute:

Nontraumatic/Chronic:

Refered pain & non-orthopedic causes:

Evaluation

Light bulb sign (left) with post-reduction comparison (right)
  • 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
  • Bedside ultrasound can be used to assess for both dislocation and successful reduction

Management

  1. Adduct the arm
  2. Apply traction along long axis of humerus
  3. Have assistant push humeral head anteriorly into glenoid fossa
  4. Apply shoulder immobilizer
  5. Obtain post-reduction radiographs
  • Note: Do not reduce chronic dislocations (>4 weeks) in the ED due to risk of arterial injury - consult ortho for open reduction

Disposition

  • Discharge after successful reduction
  • Orthopedic surgery outpatient follow-up
  • Any patient with a chronic dislocation requires orthopedic consult in the ED for consideration of operative reduction due to the risk of arterial injury

See Also

External Links

References

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