Facial Trauma 2: Describing Fractures

Question 1

Define fracture

Answer 1

A break in the continuity of a bone

Question 2

Define displacement

Answer 2

The extent to which the two sides of the fracture have moved from their normal position.

(Displaced = all way through, undisplaced= not all the way through the bone)

Question 3

Define angulation

Answer 3

The angle by which one fragment has moved in comparison to its previous position

Question 4

Define a compound fracture

Answer 4

A fracture which is open to external skin/mucosa (AKA open fracture)

Most mandible features are compound ones because you can’t really get into it without tearing the mucosa

Question 5

Define comminuted fracture

Answer 5

A complex fracture pattern with more than two bone fragments at the fracture site.

Question 6

Define pathological fracture

Answer 6

Fracture that occurs in an area of bone that has been critically weakened by disease (eg cancer, osteoradionecrosis, MRONJ, very large cyst)

Question 7

What are the thinner bones of the face/skull?

Answer 7

Lateral bones or maxilla
Lateral wall of the nose
Nasal septum

Question 8

What are the thicker bones of the face/skull?

Answer 8

Zygomatic arch

Question 9

What is the implication of a bony eye socket injury/fracture? (Ie issue with bones)

Answer 9

Causes a change in volume of the socket

If volume increases, eye goes in = inopthalmos
If volume decreases, eye pops out =exophthalmos

Question 10

What is the implication of mandible ridge resorption?

Answer 10

Significant in elderly people as it can cause a fracture in the thinnest area of the mandible. The thinnest part is the place where fractures are the most unstable.

Thin areas in an atrophic mandible can cause a bilateral fracture and cause a lot of displacement.

Question 11

How do muscles act to cause further displacement of fractures?

Answer 11

Back muscles = masseter, temporalis, pterygoid muscles= pull condyle and ramus UP

Front muscles = hyoid muscles = pull chin DOWN

Therefore, fracture is unstable and will swing (Like a bucket handle). This is hard to treat.

Note: an injury in front of the lingula will cause IDN damage so lip/tongue numbness can be present.

Question 12

Where does the temporalis run and what implication does its impingement cause?

Answer 12

Runs below the zygomatic arch and impingement may cause trismus

Question 13

Where does the infraorbital nerve run along and what happens if it is damaged?

Answer 13

Runs along the orbital floor. If the floor of the orbit has fractured and damaged the nerve along the way, it can cause numbness of the cheek/upper lip/side of nose

Question 14

Explain how a retrobulbar haematoma can occur?

Answer 14

• Very good blood supply in head and neck
• therefore venous drainage in eyes and midface can be an issue
  -If pressure increases in any of these areas, the arterial blood supply is not affected.
• BUT venous drainage may be compromised/stopped
• So if you get an injury to midface/ orbits and it causes an increase in pressure (due to change of volume etc), then it can cause a retrobulbar (behind the eye) haematoma.
• RH can cause the venous drainage of the retinal veins to stop –> congestion in retina –> pain and blindness due to retinal death

Question 15

What is the difference between a closed and open fracture ?

Answer 15

A closed fracture is a fracture without penetrating the skin barrier
An open one does penetrate the skin barrier and care needs to be taken to clear the site of the wound.

Question 16

Does open or closed fractures have better access?

Answer 16

Compound/ open fractures have better access

Question 17

Which areas of the mandible are likely to be compound fractures?

Answer 17

Front part - body of the mandible/mental/Parasymphysis fractures are likely to be compound because they involve the teeth and therefore get infected (but easier to access)

Back part - condyle/ramus/angle/ coronoid process fractures tend to fracture in a predictable manner but are harder to access (location).

Question 18

Why are mandible fractures often bilateral?

Answer 18

The mandible is a curved bone and has limited mobility at each end.
Because it is fixed at two points (the condyles), if force is applied in the front = the force is also transmitted at the condyles

For example, if there is a force in the left premolar area, the right condyle will take some of that force

Force at the chin can cause forces to be transmitted to both condyles and cause bilateral condyle fractures.

Question 19

What is a guardsman fracture?

Answer 19

fracture of the chin which causes all the teeth take the force and damages both condyles as a result

(guardsman because when they faint they fall face flat)

Question 20

Why is a zygoma fracture a tripod fracture?

Answer 20

Because it gets fractures at 3 of its processes
1. F-Z suture (zygomaticofrontal)
2. zygomatic arch
3. maxillary wall

Question 21

What are the presentation of a zygomatic fracture?

Answer 21

1. Flattening of the cheek prominence - cosmetic problem
2. Anaesthesia of the infraorbital nerve - numbness of cheek/side of nose/ upper teeth
3. Change in volume of orbital floor - affects vision due to the volume change and fat/muscle entrapment (restricted ocular movement in that side)

Question 22

Is it possible to get an isolated zygomatic arch fracture?

Answer 22

Yes - direct blow to the zygomatic arch

Just looks like a dent in someone’s cheekbone

Question 23

What happens if there is injury to all parts/attachments of the zygomatic bone?

Answer 23

The fragment can be pushed in/out resulting in volume changes
If not fixed, huge effect on aesthetics and vision

Question 24

What was Le Fort’s theory on fractures?

Answer 24

He noticed a pattern in the way fractures occurred.
Tested this by dropping cannons on cadaver’s faces and then dissecting them to see the pattern of the fracture.
There is 3 types of Le Fort fractures.

Question 25

What is a Le Fort 1,2 and 3 fracture?

Answer 25

Pull up diagram to help visual these:

Le Fort 1= Occurs above the teeth apices
Usually in the lower face and can affect occlusion

Le Fort 2= occurs in the maxilla/nose. Extends from zygomatic buttress, into the orbital floor and also involves the nose.

Le Fort 3= Occurs in the maxilla, zygomas and orbital floor

Can happen bilaterally but you can also get different Le fort fractures on different sides of your face

Question 26

What type of fractures involve the occlusion?:

Answer 26

Mandible and Le Fort fractures involve the occlusion. Zygomatic fractures do not involve the occlusion