Shoulder dislocation

Question 1

Why are shoulder dislocations quite common?

Answer 1

it is a highly mobile joint that sacrifices stability for an increased range of movement

Question 2

If shoulder dislocations are not managed appropriately what can occur?

Answer 2

chronic joint instability and chronic pain

Question 3

What is the most common type of shoulder dislocation?

Answer 3

anteroinferior (usually just called anterior)

Question 4

How is an anterior dislocation of the shoulder usually done?

Answer 4

caused by force being applied to an extended, abducted and externally rotated humerus

Question 5

When is a posterior dislocation of the shoulder usually done?

Answer 5

seizures or electrocution but can occur through trauma (direct blow to anterior shoulder or force through a flexed adducted arm)

Question 6

What kind of shoulder dislocation is often missed?

Answer 6

Posterior as radiographic evidence is often subtle

Question 7

What are the clinical features of shoulder dislocations?

Answer 7

painful shoulder, reduced mobility, instability, reluctant to move arm

Question 8

What are the features on examination of shoulder dislocations?

Answer 8

asymmetry with the contralateral side, loss of shoulder contours, anterior bulge from head of humerus, assess neuromuscular status of the arm

Question 9

What nerves can be compromised usually in shoulder dislocations?

Answer 9

axillary and supra scapular nerves

Question 10

What are some bony injuries associated with shoulder dislocation?

Answer 10

Bony bankart lesions, hill sachs defects, fractures of the greater tuberosity and the surgical neck of humerus

Question 11

What are bony bankart lesions?

Answer 11

fractures of the anterior inferior glenoid bone usually present in those with recurrent dislocations

Question 12

What are Hill Sachs defects?

Answer 12

impaction injuries to the chondral surface of the posterior and superior portions of the humeral head (80% of traumatic dislocations)

Question 13

What are some labral ligament or rotator cuff injuries that may occur with shoulder dislocation?

Answer 13

Bankart lesions (avulsions of the anterior labrum and inferior glenohumeral ligament) glenohumeral ligament avulsions, rotator cuff injuries

Question 14

What investigations are done for a shoulder dislocation?

Answer 14

plain radiographs, trauma shoulder series

Question 15

What would you see on an anterior posterior x ray of a shoulder dislocation?

Answer 15

humeral head visibly out of the glenoid fossa, the Y scapular view will also show this

Question 16

What is the light bulb sign?

Answer 16

suggests posterior dislocation as the humerus is fixed in internal totation

Question 17

If rotator cuff or labral injuries are suspected what imaging should be done?

Answer 17

MRI

Question 18

What is the management for a shoulder dislocation?

Answer 18

A and E trauma assessment, stabilise and examine other injuries, analgesia, reduction (closed and Hippocratic method), immobilisation, rehab, assess neuromuscular status before and after the reduction, broad arm sling, 2 weeks immobilisation, physiotherapy, may need surgery in future

Question 19

Why might you need future surgery for shoulder dislocations?

Answer 19

shoulder pain, joint instability, large hill sachs defects or large bony bankart lesions

Question 20

What are the complications of shoulder dislocations?

Answer 20

chronic pain, limited mobility, stiffness, recurrence, adhesive capsulitis, nerve damage, rotator cuff injury, degenerative joint disease