Elbow Dislocation

Question 1

Epidemiology of elbow dislocations

Answer 1

Young adults (25% of injuries)

Question 2

Classifications of dislocations

Answer 2

Simple vs complex

Complex = concomitant fracture

Question 3

How do elbow dislocations usually displace?

Answer 3

90% occur posteriorly

50% suffering bone injury

Question 4

What gives elbow joint stability?

Answer 4

Static = humeroulnar joint + medial and collateral ligaments
Radiocapetellar joint, joint capsule, common flexor and extensor origin tendons (minor)

Dynamic = Surrounding musculature of elbow joint (anconeus, brachialis, triceps brachii)

Question 5

Are elbow dislocations common in children?

Answer 5

No they are rare.

A supracondylar type fracture should be suspected when a child has a deformed and painful elbow.

Question 6

What happens to the stabilisers in traumatic dislocation?

Answer 6

They are damaged and there is loss of static stabilisation

This leads to ongoing instability

Question 7

Mechanism of injury

Answer 7

Typically following a high-energy fall.

Question 8

Clinical features

Answer 8

Painful and deformed joint.

Swelling + decreased function and can usually be near immobile.

The joint is usually in near full extension.

Disruption of equilateral triangle of elbow.

Question 9

Examinations done in elbow dislocation

Answer 9

Joint examination + complete neurovascular examination of upper limb.

Upper and lower limb should also be examined.

Question 10

Common nerve complications of dislocation

Answer 10

Ulnar nerve neuropraxia

Question 11

Other neurovascular injury

Answer 11

Arterial injury of brachial artery.

However there is a good capillary refill still because of rich collateral circulation in elbow.

If there are any concerns over pulses Doppler USS should be done.

Question 12

Ix of elbow dislocations

Answer 12

In significant trauma;
Resuscitation, investigation and management should be done per ATLS (advanced trauma life support) protocol.

For stable patients AP + lateral X-ray should be done.

CT imaging is only done if there is associated fractures.

Question 13

X-ray findings.

Answer 13

Loss of radiocapitellar and ulnotrochlear congruence

Question 14

Initial management of elbow dislocation.

Answer 14

Examination, documentation of neurovascular status

Analgesia +/- sedation

Closed reduction

Apply elbow backslab once reduced to keep elbow at 90 degrees

Question 15

Explain closed reduction of elbow.

Answer 15

In line traction method (method 1)

Manipulation of the olecranon (method 2)

After this elbow can be flexed to 90 degrees to reassess the equilateral triangle of the elbow (which should be restored)

Apply elbow back slab to keep at 90 degrees

Plain film radiograph is required to confirm reduction

Reassess neurovascular status

Question 16

Post-reduction management

Answer 16

Depends on associated fracture present.

Soft tissue damage -> LCL leads to elbow being stable in pronation.
MCL damage leads to elbow being stable in supination

Question 17

Management post-reduction in simple elbow dislocation

Answer 17

With no fracture orthopaedic management can be done as outpatient with short period of immobilisation (5-14 days)

Early rehab with supervised range of motion exercises in stable arc can be introduced.

Question 18

Management post-reduction if there is complicated dislocation;

e.g.
Fracture
Open type injury
Neurovascular compromise

Answer 18

Operative fixation can be considered such as ORIF of coronoid, radial head or olecranon with appropriate soft tissue repair of LCL and MCL

Question 19

Complications of elbow dislocation

Answer 19

Early stiffness with loss of terminal extension. (Can be reduced by early tx and rehab)

Stretching of ulnar nerve

Brachial artery and median nerve injuries are rare.

Recurrent instability (although low recurrence rate <2%)

Question 20

What is terrible triad?

Answer 20

Elbow dislocation with…

LCL injury
Radial head fracture
Coronoid fracture

Question 21

Issues with Terrible triad

Answer 21

This combination causes an extremely unstable elbow.

Associated with a poor outcome.

Recurrent problems with instability, stiffness and arthrosis.

Question 22

Mechanism of injury of terrible triad

Answer 22

Forces applied to join from fall onto an extend arm with rotation.

This leads to posterolateral dislocation (instead of posterior)

Question 23

Management of terrible triad.

Answer 23

Operative fixation of each component

Radial head -> ORIF or arthroplasty

LCL reconstruction

Coronoid ORIF

MCL reconstruction is sometimes done at the same time