Shoulder dislocation

Question 1

What are the kinds of shoulder dislocation?

Answer 1

Anterior dislocation

• Over 90% dislocations
• Head of humerus moves anteriorly in relation to glenoid
• Can occur when arm forced backwards whilst abducted and extended at shoulder

Posterior dislocation

• Associated with electric shock and seizures
• Much less common

Question 2

Associated damage with shoulder dislocation

Answer 2

Axillary nerve damage is a key complication - loss of sensation to badge area, motor weakness in deltoid and teres minor

Glenoid labrum tear (rim of cartilage around the glenoid cavity)
- Bankart lesions - tears to anterior labrum (occur with repeated anterior subluxations or dislocations of the shoulder)

Hill-Sachs lesions - compression fractures of the posterolateral part of the head of the humerus

Associated fractures and rotator cuff tears (particularly in elderly)

Question 3

Important to assess patients with a shoulder dislocation for…

Answer 3

Fractures

Vascular damage (e.g., absent pulses, prolonged capillary refill time and pallor)

Nerve damage (e.g., loss of sensation in the “regimental patch” area)

Question 4

Investigations in dislocated shoulder

Answer 4

Mostly a clinical diagnosis

X-rays can be used in acute setting to exclude fractures and confirm dislocation

MR arthrography with contrast can be done to assess for shoulder damage (e.g. Bankart and Hill-Sachs lesions) and for planning for surgery.

X-Ray is done after reduction to confirm success

Question 5

Acute management of dislocated shoulder

Answer 5

Analgesia, muscle relaxants and sedation as appropriate
- Gas and air (e.g., Entonox) may be used

A broad arm sling can be applied to support the arm

Closed reduction of the shoulder (after excluding fractures) - ASAP as muscle spasm occurs over time making it harder to relocate shoulder

Dislocations associated with a fracture may require surgery

Post-reduction x-rays

Immobilisation for a period after relocation of the shoulder

Question 6

Ongoing management

Answer 6

Physiotherapy - to improve the function of the shoulder and reduce the risk of further dislocations.

Shoulder stabilisation surgery

Question 7

After a shoulder dislocation there is high risk of…

Answer 7

Recurrent dislocations

Particularly in younger patients