1. Summary
2. How are they classified?
3. How common are they and how do they occur?
4. What do they look like - clinically?
5. What radiological investigations should be ordered?
6. What do they look like on x-ray?
7. When is reduction (non-operative and operative) required?
8. Do I need to refer to orthopaedics now?
9. What is the usual ED management for this fracture?
10. What follow-up is required?
11. What advice should I give to parents?
12. What are the potential complications associated with this injury?

1. Summary

• This guideline refers to acute traumatic dislocation of the glenohumeral joint. 
• Acromioclavicular joint dislocation is a separate entity which is not covered in this guideline.
• Multidirectional recurrent shoulder instability or suspected wilful dislocation are less common entities - both are beyond the scope of this guideline.
  
  
• Acute shoulder dislocations should be reduced in the Emergency Department, placed into a sling and have radiographs to confirm reduction.
• The post-reduction radiographs should be checked very carefully for a glenoid rim fracture (Bankart lesion), with early CT and orthopaedic follow up arranged when these are present.
• ALL first-episode shoulder dislocations should have follow-up arranged with either Sports Medicine, Physiotherapy or Orthopaedics, for evaluation of risk factors for recurrent dislocation.
• Children with recurrent unidirectional dislocations may benefit from MRI and surgical repair.

2. How are shoulder dislocations classified?

• Traumatic, unidirectional
  • First time dislocators - can cause damage to underlying structures - may require surgery
  • Repeat dislocators - can be related to MDI or structural issues
  • 95% will be an anterior dislocation
• Atraumatic, multidirectional (beyond the scope of this guideline)
• Atraumatic, voluntary dislocators (beyond the scope of this guideline)
  • May not be symptomatic, but can pop shoulder in and out as a “party trick”. More common in younger children.
    • Discourage popping trick. Most will grow out of it
  • Sub-subgroup voluntary, wilful dislocators
    • This rare subgroup may have superimposed psychosocial factors contributing to the need to wilfully dislocate shoulder and seek medical attention and / or chronic pain syndromes.
    • Require specialist management

 

3. How commonly do they occur?

• Shoulder dislocation is most commonly seen in adults and adolescents, and is very seldom seen in the younger child
• Shoulder dislocation is one of the most common injuries sustained during overhead sports.  With the increase in competitive sports participation in younger children and adolescents, there is a general rise in the incidence of shoulder instability injuries.
• Posterior dislocations are uncommon; where they occur they are usually associated with seizures or electrocution.

4. What do they look like clinically?

• On History
  • Acute traumatic dislocations will have history of trauma, typically from sports or a fall
  • In anterior dislocations (95%) arm usually in the abducted and externally rotated position (i.e. hand overhead or outstretched)
• On examination
  • Lack of humeral head palpable below the acromion and noted fullness or ball like shape anterior to acromion.
  • Patient holding shoulder adducted and internally rotated against the body, with pain on abduction or rotation.
  • Shoulder may have self-reduced prior to presentation, in which case the diagnosis will be made predominantly on history. The patient will still have reluctance to move, and will need radiographs and follow-up arranged as with other patients.
  • Numbness or paraesthesia over the deltoid (‘regimental badge’ area) suggests axillary nerve injury. This should be tested before and after any manipulation
  • Other neurological findings may be present (eg brachial plexus injury) but are rare

5. What Radiological Investigations should be ordered?

X-Ray:

ALL reductions should be confirmed with a post-procedure radiograph, and the X-ray specifically checked for Hill-Sachs lesion or glenoid rim fracture , which may be subtle.  Presence of glenoid fracture on X-ray should prompt early CT and surgical attention (within a week): even small bony rim fractures have an associated fibrocartilaginous lesion, with implications for shoulder stability.

• First time, traumatic shoulder dislocations in young patients are often associated with important soft-tissue structural damage.  ALL of these injuries should have early physiotherapy / sports medicine or orthopaedic follow up (within 3-4 weeks) due to the risks of ongoing instability.
• There is emerging evidence that early MRI can help stratify risks of repeat dislocation. This can be discussed with the professional being seen for follow-up.

6. What do they look like on x ray?

• Discontinuity between the glenoid fossa and the humeral head (anterior dislocation)

• The following is an xray of a self-reduced shoulder dislocation, with a small density on the medial aspect of the glenoid which is actually a displaced large glenoid fracture on CT

• Another glenoid rim fracture is shown below

7. When is reduction (non-operative and operative) required?

• All shoulders that are still dislocated should be reduced emergently.  This can be performed with a variety of manoeuvres - gentleness of technique is more important than which method is chosen.  Reduction will often take place under procedural sedation/analgesia in paediatric practice.
• Shoulders that are irreducible in ED, which may signify interposed soft tissue or bony fragments, will need to go to theatre for reduction - this is rare.

8. Do I need to refer to Orthopaedics now?

• Immediate referrals should be made in the following circumstances
  • Shoulder dislocation with acute fracture (glenoid or proximal humerus)
  • Shoulder dislocations that are irreducible
  • Shoulder dislocations where there is neurovascular compromise Suspected wilful dislocators, prior to attempted reduction (management of these patients should involve pain team or psychology - it is important to teach them how to reduce the dislocation themselves).
  • If a brachial plexus palsy is present, consultation with orthopaedics should be undertaken. 

9. What is the usual ED management for this Dislocation?

• Reduction as described in point 7 above
• Place the arm in a sling (shoulder immobilizer) for only 1-2 weeks
• Post- reduction x-rays
• Immediate CT if suspicion of fracture on x-ray
• Neurological examination (in particular the axillary nerve) should be performed and documented pre-and post-reduction

10. What follow up is required?

• All shoulder dislocations should have some form of follow-up arranged
  • Any radiological abnormalities such as glenoid fracture or large Hill-Sachs lesions post-reduction need early orthopaedic consultation.  Where surgery is necessary to improve shoulder stability, results are better when this is performed early.
  • Uncomplicated first time traumatic dislocators should have early follow up in 2-4 weeks to assess stability - this might be with Sports Medicine, Physiotherapy or Orthopaedics.  There is emerging evidence that MRI can help stratify risks for repeat dislocation - merits of this can be discussed at follow up. 
  • Additionally, physiotherapy should be arranged to commence in 1-2 weeks, focusing on strengthening deltoid, rotator cuff muscles and scapular stabilisers. Sling is only required for comfort for 1-2 weeks
  • Recurrent traumatic dislocators should have non-urgent orthopaedic follow-up, as they may benefit from shoulder stabilization electively.

11. What advice should I give to parents?

• Shoulder dislocations are common injuries. There is a risk of recurrent dislocation but these are manageable.
• Sling is not required for more than 1-2 weeks.
• Commencement of a physiotherapy program in the weeks after injury will help prevent long term stiffness or vulnerability to recurrent injury.
• Provide printed information regarding injury care for shoulder dislocation

12. What are the potential complications of this injury?

• Older Adolescents who have a shoulder dislocation have a very high risk of recurrence (up to 90%).
• Missed fractures, such as glenoid rim fractures, portend worse prognosis if not addressed early, hence the importance of appropriate follow up.
• Injury to the brachial plexus is possible but rare. These usually occur in high energy injuries eg motor vehicle accidents.
• Injury to the axillary nerve is uncommon, though more frequent than brachial plexus injury. Most resolve with expectent management.
  

13. References:

1. Paletta Jr. GA. Treatment of glenohumeral instability in the pediatric athlete. Oper. Tech. Sports Med. 1998;
2. Franklin CC, Weiss JM. The Natural History of Pediatric and Adolescent Shoulder Dislocation. J. Pediatr. Orthop. 2019;doi:10.1097/BPO.0000000000001374
3. Lin, K. et al. Pediatric and adolescent anterior shoulder instability: clinical management of first-time dislocators, Curr Opin Pediatr 2018;30(1):49-56
4. Roberts et al, Natural History of Primary Anterior Dislocation of the Glenohumeral Joint in Adolescents. Bone Joint J 2015;97-B:520-6

Last updated October 2020