Pathology of Orbital Trauma and Fractures

Question 1

What is the direction of a blowout fracture?

Answer 1

An outward fracture of orbital bones and involves the medial wall/floor

Results in increased intraorbital volume and enophthalmos

Question 2

What is the direction of a blow in fracture?

Answer 2

This is a fracture of the orbital bones inwards into the orbital space
This results in decreased orbital volume and proptosis

Question 3

What is the Buckling theory?

Answer 3

Transmission of force by bone conduction through the orbital rim to the floor and wall

Rippling of bones causes distortion followed by fracture

Question 4

What is the Hydraulic Theory?

Answer 4

Force of the blow received by the globe, not the orbital rim

• Globe sustains a direct blow, pushing it into the orbit

Question 5

What are Le fort fractures?

Answer 5

Horizontal fractures that involve the maxilla bilaterally

Question 6

What is the Le Fort II (pyramidal)?

Answer 6

• Separates midface from skull base
• medial orbital wall affected

Question 7

What does a medial wall fracture involve?

Answer 7

Involves maxilla, lacrimal and ethmoid bones
usually associated with orbital floor fractures, rarely isolated

Question 8

What are the signs of a medial wall fracture?

Answer 8

Periorbital emphysema

defective motillity

epistaxis

Question 9

What are the orbital floor fracture signs?

Answer 9

• Ecchymosis (bruising)
• infraorbital nerve anesthesia
• enophthalmos (posterior globe displacement
• diplopia

Question 10

What are the orbital roof fracture signs?

Answer 10

• Haematoma of the upper lids
• inferior or axial globe displacement
• Ptosis
• limitation elevation and depression of the eye

Question 11

What are the complications of orbital trauma?

Answer 11

• Enophthalmos
• Diplopia from muscle entrapment
• Foreign bodies
• globe rupture
• retinal detachment

Question 12

What are the features of blow out fracture?

Answer 12

• Intraocular pain
• Diplopia/inability to move the eye
• Nerve damage
• Globe Displacement
• Odema
• Haematoma

Question 13

What bones make up the orbital roof?

Answer 13

Frontal, lesser wing of sphenoid

Question 14

What bones make up the orbital floor?

Answer 14

Maxilla, zygomatic (anteriorly) and palatine (posteriorly)

Question 15

What bones make up the medial wall?

Answer 15

Ethmoid, lacrimal, body of sphenoid (posteriorly), frontal (superiorly), maxilla (inferiorly)

Question 16

What bones make up the lateral wall?

Answer 16

Zygomatic (anteriorly), greater wing of sphenoid (posteriorly)

Question 17

What is the inflammation phase of bone healing?

Answer 17

• Hematoma forms from cells in blood and bone marrow
• This then coagulates between and around the fracture ends which forms a template

There is an acute inflammatory response in first 24 hrs

Question 18

What is the repair phase of bone healing?

Answer 18

Direct - only with extremely low bone fragment movement or fragment compression

Indirect - low degree of stability considerable fragment movement

Question 19

What is the remodelling phase of bone healing?

Answer 19

• Resorption of hard callus
• woven bone gradually converted to lamellar bone
• medullary cavity reconstituted
• bone restructured in response to stress and strain