Treatment of Anterior Shoulder Dislocation
Immediate closed reduction is the primary treatment for acute anterior shoulder dislocation, followed by immobilization and subsequent advanced imaging to assess for associated injuries that may require surgical intervention.
Acute Management
Initial Reduction
- Perform closed reduction as soon as possible to minimize pain, prevent neurovascular complications, and reduce risk of further soft tissue damage 1, 2
- Multiple reduction techniques are available, including patient self-reduction methods (modified Milch technique) which can achieve successful reduction in approximately 72% of cases without sedation 2
- Mean reduction time is approximately 10 minutes when using self-reduction techniques 1
Procedural Sedation Options
If sedation is required for reduction:
- Etomidate provides effective sedation with shorter duration (median 10 minutes) compared to midazolam (23 minutes) for shoulder reduction procedures 3
- Propofol with fentanyl is also effective, though brief bag-mask ventilation may be required in 1-3% of cases 3
- Both agents have comparable safety profiles when administered by trained emergency physicians 3
Post-Reduction Immobilization
- Immobilize the shoulder after successful reduction
- Duration and type of immobilization should be determined based on patient age and associated injuries
Assessment for Associated Injuries
Imaging After Reduction
MR arthrography is the preferred advanced imaging modality for evaluating post-dislocation shoulder pathology 3
Key imaging considerations:
- Younger patients are more likely to have labroligamentous injuries (Bankart lesions) and persistent instability 3
- Older patients are more likely to have rotator cuff tears associated with dislocation 3
- MR arthrography has 86-100% sensitivity for detecting labral injuries and outperforms non-contrast MRI for glenohumeral ligament and anterior labral injuries 3
- MR arthrography is equivalent to CT for assessing glenoid and humeral head bone loss (Hill-Sachs lesions) while being superior for soft tissue evaluation 3
Alternative Imaging
- CT arthrography is a reasonable alternative if MRI is contraindicated, with comparable performance to MR arthrography for Bankart and Hill-Sachs lesions 3
- Plain CT should be reserved only for MRI contraindications, as it cannot assess soft tissue structures 3
Management of Complex Cases
Associated Fractures
When anterior dislocation occurs with ipsilateral humeral shaft fracture (rare injury):
- Address the fracture first with open reduction and internal fixation, then reduce the dislocation 4, 5
- Attempting joint reduction before fracture fixation carries risk of neurovascular damage 5
- Radiological union typically achieved at 14 weeks with good shoulder range of motion 5
Recurrent Instability
- Up to 80% recurrence rates have been reported after first dislocation 1
- Glenoid bone loss >10% and chronic Bankart lesions may require surgical stabilization (Latarjet procedure) to restore stability 3, 6
- Patients with recurrent dislocations who refuse or cannot undergo surgical stabilization can be taught self-reduction techniques 1
Critical Pitfalls to Avoid
- Never attempt closed reduction of the shoulder joint when there is an associated humeral shaft fracture without first stabilizing the fracture surgically 5
- Do not rely on ultrasound for assessment of Bankart or Hill-Sachs lesions, as it is inferior to MRI for both labroligamentous and bony injuries 3
- Recognize that standard MR arthrography sensitivity rates (86-100%) may not apply to clinically unstable shoulders, where sensitivity may be as low as 65% 3
- In bilateral fracture-dislocations (extremely rare), address chronic glenoid bone loss with fixation procedures along with fracture management 6