Posterior shoulder dislocation: Difference between revisions
No edit summary |
|||
| Line 1: | Line 1: | ||
==Background== | ==Background== | ||
* | *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> | ||
* | *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== | ||
Revision as of 23:52, 13 May 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
- Usually due to seizure or electric shock
- Blow to anterior shoulder
- Forceful internal rotation and adduction
- 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
- Prominence of posterior shoulder and anterior flattening of normal shoulder contour
- Patient unable to rotate or abduct affected arm
Differential Diagnosis
Shoulder and Upper Arm Diagnoses
Traumatic/Acute:
- Shoulder Dislocation
- Clavicle fracture
- Humerus fracture
- Scapula fracture
- Acromioclavicular joint injury
- Glenohumeral instability
- Rotator cuff tear
- Biceps tendon rupture
- Triceps tendon rupture
- Septic joint
Nontraumatic/Chronic:
- Rotator cuff tear
- Impingement syndrome
- Calcific tendinitis
- Adhesive capsulitis
- Biceps tendinitis
- Subacromial bursitis
- Cervical radiculopathy
Refered pain & non-orthopedic causes:
- Referred pain from
- Neck
- Diaphragm (e.g. gallbladder disease)
- Brachial plexus injury
- Axillary artery thrombosis
- Thoracic outlet syndrome
- Subclavian steal syndrome
- Pancoast tumor
- Myocardial infarction
- Pneumonia
- Pulmonary embolism
Evaluation
- 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
- 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
- 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 reduction
- Ortho follow-up
See Also
External Links
References
- ↑ Grate I Jr. Luxatio erecta: a rarely seen, but often missed shoulder dislocation. Am J Emerg Med. 2000 May;18(3):317-21.