What is the recommended approach for reducing an anterior shoulder dislocation?

Recommended Approach for Anterior Shoulder Dislocation Reduction

The external rotation method (ERM) is the recommended first-line approach for reducing anterior shoulder dislocations as it is effective, safe, and can often be performed without sedation, minimizing morbidity risks. 1

Initial Assessment and Preparation

• Obtain appropriate radiographs before attempting reduction:

  • Anteroposterior (AP) views in internal and external rotation
  • Axillary or scapula-Y view (essential for confirming dislocation type) 2
  • Ensure upright positioning for radiographs as malalignment can be underrepresented on supine imaging 2

• Check for associated injuries:

  • Hill-Sachs lesions (humeral head impression fracture)
  • Bankart lesions (anterior-inferior glenoid rim fracture)
  • Greater tuberosity fractures
  • Rotator cuff tears (more common in older patients) 2

Reduction Techniques in Order of Preference

1. External Rotation Method (First Choice)

• Position patient sitting or supine
• Adduct the affected arm against the body
• Flex the elbow to 90 degrees
• Slowly and gently externally rotate the arm
• Success rate of approximately 90% on first attempt 1
• Advantages:
  • Can often be performed without sedation
  • Relatively painless compared to other techniques
  • Quick (average time <2 minutes) 1
  • Higher patient satisfaction scores 3

2. Gentle Traction-Abduction-External Rotation (TAE) Method

• Position patient supine
• Apply gentle traction on the arm
• Slowly abduct and externally rotate
• Success rate of approximately 90% without sedation 3
• Particularly useful when ERM is unsuccessful

3. Flexion-Adduction-External Rotation Method

• Forward flex the arm
• Adduct across the body
• Apply gentle external rotation
• Success rate of approximately 81% on first attempt 4

4. Scapular Manipulation

• Position patient prone or sitting leaning forward
• Push the inferior angle of the scapula medially while an assistant applies gentle traction on the arm
• Useful as an adjunct to other techniques

Sedation Considerations

• Attempt reduction without sedation first using ERM or TAE 1, 3
• If unsuccessful or if patient has significant muscle spasm/pain, consider procedural sedation:
  • Etomidate: Shorter recovery time (median 10 min) compared to midazolam (median 23 min) 2
  • Propofol: Effective with short recovery time (approximately 15 min) 2
  • Midazolam: Effective but longer recovery time (approximately 76 min) 2

Post-Reduction Management

• Obtain post-reduction radiographs to confirm successful reduction and assess for fractures
• Immobilize the shoulder in a sling or immobilizer
• Arrange appropriate follow-up for rehabilitation

Common Pitfalls and Caveats

• Avoid forceful manipulation which can cause iatrogenic fractures or neurovascular injury
• The axillary lateral view positioning may be painful and could cause redislocation in recently reduced shoulders 2
• Older patients (>40 years) are more likely to have associated rotator cuff tears requiring further evaluation 2
• Younger patients are more prone to recurrent instability and may need more comprehensive imaging (MR arthrography) to assess labral injuries 2
• Avoid direct pressure into the axillary fossa to prevent neurovascular complications 5
• If multiple reduction attempts fail, proceed to reduction under general anesthesia rather than continuing with forceful attempts

By following this algorithmic approach prioritizing gentle, sedation-free techniques first, the morbidity associated with both the dislocation and the reduction procedure can be minimized while achieving high success rates.