How is a shoulder dislocation diagnosed and treated?

Diagnosis and Treatment of Shoulder Dislocation

For acute shoulder dislocation, obtain standard shoulder radiographs (AP in internal/external rotation plus axillary or scapula-Y view) immediately to confirm diagnosis and rule out fractures, then proceed with prompt reduction using a biomechanical technique without excessive force, followed by 1 week of relative immobilization and early physical therapy. 1, 2

Diagnostic Approach

Initial Imaging

Radiography is the preferred initial diagnostic modality for suspected shoulder dislocation 1. The standard trauma series must include at minimum:

• Anterior-posterior (AP) views in both internal and external rotation
• Axillary or scapula-Y view (critical—glenohumeral dislocations can be missed on AP views alone) 1
• Optional Stryker notch view to evaluate Hill-Sachs lesions 1

These views are vital because acromioclavicular and glenohumeral joint dislocations can be misclassified on AP views alone 1.

Advanced Imaging After Reduction

Following successful reduction, MRI shoulder without IV contrast is usually appropriate as the next imaging study when evaluating for associated soft tissue injuries 1. In the acute setting, a posttraumatic joint effusion or hemarthrosis is typically present, providing sufficient visualization of soft tissue structures without the need for contrast 1.

CT shoulder without IV contrast may be appropriate for patients in whom MRI assessment of bone loss is limited, particularly when evaluating for bony Bankart lesions or glenoid fractures 1.

Point-of-care ultrasound can expedite diagnosis in urgent care settings and confirm reduction, though this is not standard practice 3.

Treatment Protocol

Immediate Management: Reduction

Reduction should be commenced without unnecessary delay after diagnostic confirmation 4, 2. The key principles include:

• Favor a biomechanical reduction approach without analgesics initially (based on individual experience) 2
• If initial reduction fails, proceed with procedural sedation and analgesia 2
• Achieve good muscle relaxation and pain management—either systemic or topical (ultrasound-guided intra-articular lidocaine is an option) 3, 4
• Avoid excessive force during reduction 4
• Always verify successful reduction with repeat radiography to confirm reduction and rule out complications 4, 2

Post-Reduction Immobilization

Immobilize for 1 week of relative immobilization following reduction 2. This represents a shift from historical practices of longer immobilization periods. The most common contemporary approach is immobilization for 1-3 weeks 5, but the most recent guideline evidence supports just 1 week 2.

Avoid excessive immobilization—prolonged immobilization does not prevent recurrent dislocation and delays functional recovery 4, 6.

Rehabilitation Phase

Following the acute immobilization period, initiate a structured five-phase rehabilitation protocol 7:

1. Acute protection and education (0-3 weeks): Sling weaning, pain management, education
2. Movement and early strengthening (3-6 weeks): Initiate through-range resisted exercise
3. Progressive strengthening (6-12 weeks): Advance resistance training
4. Return to sport (>12 weeks): Criteria-based progression
5. High-level function: Sport-specific training

Physical therapy should target early restoration of function, coordination, and proprioception 2. Rehabilitation should be controlled and supervised 4.

Surgical Consideration

Risk Factors for Recurrent Dislocation

Surgical intervention should be discussed when the following risk factors are present 2:

• Age < 40 years (particularly < 20 years—highest risk group) 8, 2
• Male sex 8, 2
• Contact athletes or high shoulder-demand activities 8, 2
• Significant bone loss (bony Bankart, Hill-Sachs, glenoid deficiency) 5

The presence of bony injury is the most influential factor (81% of surveyed physicians), followed by patient age (69%) and contact sport participation (63%) 5.

Surgical Timing

Primary surgical stabilization may be considered in high-risk patients to prevent unacceptably high rates of recurrent instability and progressive structural pathology 8. Younger physicians increasingly favor arthroscopic stabilization, while open approaches remain an option for significant bone loss 5.

Common Pitfalls

• Missing the axillary or scapula-Y view: This is the most common imaging error—dislocations can appear reduced on AP views when they are not 1
• Failing to obtain post-reduction radiographs: Always confirm successful reduction and rule out iatrogenic fractures 4, 2
• Excessive immobilization: Prolonged immobilization (>3 weeks) does not reduce recurrence rates and impairs functional recovery 4, 6, 2
• Underestimating recurrence risk in young patients: Patients under 20 have extremely high recurrence rates with non-operative management; surgical discussion is warranted 8, 2