Shoulder dislocation

Background

Left shoulder and acromioclavicular joints with ligaments.
Shoulder anatomy, anterior.
Shoulder anatomy, posterior.
  • Humerus separates from the scapula at the glenohumeral joint
  • Partial dislocation of the shoulder is referred to as subluxation
  • Dislocation duration inversely correlated with likelihood of successful ED reduction

Shoulder dislocation types

Clinical Features

  • Shoulder pain
  • Decreased shoulder range of motion

Comparison of Shoulder Dislocation Clinical Features

Finding Anterior (~95%) Posterior (~5%) Inferior (<1%)
Arm position Arm maintained in abduction and external rotation Posterior aspect of shoulder unusually prominent Humerus fully abducted / Hand on or behind head
Shoulder appearance Loss of normal rounded appearance with stretching of the deltoid muscle (i.e., "squared off") Anterior aspect of shoulder appears flattened
Range of motion Difficulty touching affected arm to contralateral shoulder due to pain Inability to rotate or abduct affected arm Humeral head palpable in axilla or lateral chest wall
Mechanism Most common; range of mechanisms Forceful internal rotation and adduction (e.g., blow to anterior shoulder, seizure, eletric shock) Forceful hyper-abduction of arm

Differential Diagnosis

Shoulder and Upper Arm Diagnoses

Traumatic/Acute:

Nontraumatic/Chronic:

Refered pain & non-orthopedic causes:

Evaluation

Workup

  • Plain film X-ray
    • Include anteroposterior, scapular Y, and axillary views
    • Associated fractures include:
      • Hills-Sachs: cortical depression in the humeral head
      • Bankart: glenoid labrum disruption with bony avulsion
      • Humeral greater tuberosity fracture
  • Consider joint ultrasound

Diagnosis

Management

Reduction

Post-Reduction

  • Post-reduction film to confirm
  • Sling and swathe or shoulder immobilizer x1 week / until orthopedics follow-up
    • Encourage daily range of motion exercises (minus abduction + external rotation) to prevent adhesive capsulitis

Disposition

  • Uncomplicated dislocation can be discharged after reduction

Prognosis

  • Recurrence rate around 27% if older than 30 years and 72% if younger than 23 years[2]

See Also

External Links

References

  1. Intra-articular lignocaine versus intravenous analgesia with or without sedation for manual reduction of acute anterior shoulder dislocation in adults (Review) Cochrane Database Syst Rev. 2011 Apr 13;(4):CD004919 full text
  2. Watson S, Allen B, Grant JA. A Clinical Review of Return-to-Play Considerations After Anterior Shoulder Dislocation. Sports Health. 2016; 8(4):336-341.