Themes

Key landmarks
 Clinically relevant
 “Gotcha” injuries
○ Easy-to-miss, land you in trouble
Simplify approaches to classification,
where possible
 Differentiating one fracture pattern from
another

Of Processes and Terminology
Of Processes and Terminology
Frontal
Bone
Temporal
Bone
Maxillary
Bone
Of Processes and Terminology
Frontal
Bone
Frontal process
of zygomatic bone
Temporal
Bone
Maxillary
Bone
Of Processes and Terminology
Frontal
Bone
Zygomatic process
of frontal bone
Temporal
Bone
Maxillary
Bone
Of Processes and Terminology
Frontal
Bone
Temporal
Bone
Maxillary
Bone
Maxillary process
of zygomatic bone
Of Processes and Terminology
Frontal
Bone
Temporal
Bone
Maxillary
Bone
Zygomatic process
of maxillary bone
Clinical Relevance of Fracture Diagnosis

Fracture repair timing
 Ideally <6-12h
○ Before onset of edema
○ Usually infeasible due to other injuries
 3-7d post-injury
○ Edema begins to settle
Early fixation (<10d) reduces
errors from scar and callus
 Timely diagnosis is critical
 CT is critical because underlying
deformity may be obscured by
edema

* Diagram and photo credits: www2.aofoundation.org and shenbagamhospital.org
Classification of Facial Fractures

Solitary Strut





Isolated frontal or maxillary sinus wall
Isolated zygomatic arch
Nasal arch
Isolated orbital floor, or medial wall or
rim
Complex Strut
 Naso-orbitoethmoidal, nasomaxillary
 Zygomaticomaxillary complex

Transfacial
 LeFort I, II, III

Mandibular
* Modified from Kassell EE, Gruss JS: Neuroimaging Clin N Am 1:259, 1991
Frontal Sinus Fractures
Direct blow to supraorbital
region
 High force injury (>800 lbs)
 Anterior wall

 Forms the frontal bar
 Contributes to facial
projection
 Foundation for vertical
buttresses

Posterior wall
 Separates sinus from cranial
vault
Projection
Frontal Sinus Fractures
Coronal CT: Frontal Mucocele
Key landmark: nasofrontal duct
 Duct dysfunction may lead to
mucocele formation
 Frontal sinus obliterated
prophylactically

 Mucosa stripped and sinus packed with
bone or fat
Coronal CT: Normal Example
Normal Duct
59F Normal
36M Facial injury ten years ago
Nasal Bone Fracture

Axial CT: Simple Nasal Bone Fracture
Common
 50% of all facial fractures

Watch for:
 Septal hematoma
○ Saddle nose deformity
 Anterior nasal spine
fracture
○ Chronic pain
 Involvement of medial
orbital wall
61M Pedestrian struck
Nasal Bone Fracture
Axial CT: Paraseptal Hematoma

Common
 50% of all facial fractures

Watch for:
 Septal hematoma
○ Saddle nose deformity
 Anterior nasal spine
fracture
○ Chronic pain
 Involvement of medial
orbital wall
* Photo credit: http://images.rheumatology.org
22M Blunt trauma to face
Saddle Nose*
Nasal Bone Fracture

3D SSD: Anterior Nasal Spine
Common
 50% of all facial fractures

Watch for:
 Septal hematoma
○ Saddle nose deformity
 Anterior nasal spine
31M Punch to face
Lateral View: Anterior Spine Fracture
fracture
○ Chronic pain
 Involvement of medial
orbital wall
31M Drunk, fell
Nasal Bone Fracture

Common
Axial CT: Naso-Orbital Ethmoidal Fracture
 50% of all facial fractures

Watch for:
 Septal hematoma
○ Saddle nose deformity
 Anterior nasal spine
fracture
○ Chronic pain
 Involvement of medial
orbital wall
66M Gunshot wound
NOE Fractures

Fractures involve:
 Nasal bones
 Frontal process of maxilla
 Medial canthal region
 Ethmoid sinus and walls

Strongly associated with:
 Cribiform plate injury
 Intracranial injury
 Dural tears
Nasal bone
 Globe injury
Maxilla
Lacrimal bone
Orbital plate of ethmoid
NOE Fracture
Fractured nasal bones
Associated open frontal sinus fracture
Fractured medial wall
Associated orbital roof blowout
61M Pedestrian struck
NOE Fractures
Key landmark: lacrimal fossa
 Medial canthal tendon inserts
around fossa

 Formerly “ligament”
 Complex structure intimately
related to orbicularis oculi

Fracture may cause:
 Telecanthus
 Globe malposition

Look for nasolacrimal duct to
find the lacrimal fossa
NOE Fractures
Key landmark: lacrimal fossa
 Medial canthal tendon inserts
around fossa
 Fracture may cause:

 Telecanthus
 Globe malposition

Look for nasolacrimal duct to
find the lacrimal fossa
* Photo credit: Pham et al. “Computer Modeling and Intraoperative Navigation in Maxillofacial Surgery”. Otolaryngology 137(4): 624-631.
NOE Fractures
Coronal CT: Normal Lacrimal Fossa
Key landmark: lacrimal fossa
 Medial canthal tendon inserts
around fossa
 Fracture may cause:

 Telecanthus
 Globe malposition

Coronal CT: Normal Nasolacrimal Duct
Look for nasolacrimal duct to
find the lacrimal fossa
59F Normal study
NOE Fracture Classification

Markowitz-Manson Classification:
 Type I
○ Fractured piece is large
○ Medial canthal tendon intact
○ Fixation of bony fragment restores
canthal anatomy
 Type II
○ Comminution
○ Canthus tendon is attached to a small
bone fragment
 Type III
○ Comminution with avulsion of medial
canthal tendon
○ Cannot reliably differentiate from
Type II on imaging
* Hopper et al. Diagnosis of Midface Fractures with CT: What the Surgeon Needs to Know. Radiographics. 2006 May-Jun;26(3):783-93
NOE Fracture Classification
Axial: Fractured Nasal Bones & Medial Walls
3D SSD: Manson Type I
Coronal CT: Fractured Medial Wall and Floor
Lacrimal
Fossa
Nasolacrimal
Duct
38M Fell off bike onto face
NOE Fracture Classification

Markowitz-Manson Classification:
 Type I
○ Fractured piece is large
○ Medial canthal tendon intact
○ Fixation of bony fragment restores
canthal anatomy
 Type II
○ Comminution
○ Canthus tendon is attached to a small
bone fragment
 Type III
○ Comminution with avulsion of medial
canthal tendon
○ Cannot reliably differentiate from
Type II on imaging
3D SSD: Manson Type II
63F Massive blunt force trauma
* Hopper et al. Diagnosis of Midface Fractures with CT: What the Surgeon Needs to Know. Radiographics. 2006 May-Jun;26(3):783-93
NOE Fracture Classification

Markowitz-Manson Classification:
 Type I
○ Fractured piece is large
○ Medial canthal tendon intact
○ Fixation of bony fragment restores
canthal anatomy
 Type II
○ Comminution
○ Canthus tendon is attached to a small
bone fragment
 Type III
○ Comminution with avulsion of medial
canthal tendon
○ Cannot reliably differentiate from
Type II on imaging
3D SSD: Manson Type III
53M Gunshot wound
* Hopper et al. Diagnosis of Midface Fractures with CT: What the Surgeon Needs to Know. Radiographics. 2006 May-Jun;26(3):783-93
NOE Fracture Classification
• Always comment on:
• The degree of comminution
• Bilateral involvement
•
•
•
Nasofrontal ducts likely disrupted
Risk of mucocele formation
Frontal sinuses are surgically obliterated
* Hopper et al. Diagnosis of Midface Fractures with CT: What the Surgeon Needs to Know. Radiographics. 2006 May-Jun;26(3):783-93
Zygoma

“Cornerstone” bone
 Attachments to frontal, temporal, sphenoid
bones of skull base
 Forms large portions of the orbital floor
and lateral orbital wall
 Attachment to maxilla
 Contributes to projection, width & height

Accurate diagnosis and reduction
is crucial for:
 Restoring orbital volume
 Restoring facial projection, height, width
 Serving as reference for maxilla in Le
Fort-type injuries
Zygoma Fractures

“Tripod” fractures
 Region of zygomaticofrontal suture
 Region of zygomaticotemporal suture
 Region of zygomaticomaxillary suture

“Tetrapod” fractures
 Zygomaticosphenoid suture
3D SSD
 Often involves lateral maxillary wall

Often the zygoma itself is intact
 Weaker bones and suture lines fracture
around zygoma
24M Assaulted
Zygoma Fractures

“Tripod” fractures
 Region of zygomaticofrontal suture
 Region of zygomaticotemporal suture
 Region of zygomaticomaxillary suture

“Tetrapod” fractures
 Zygomaticosphenoid suture
 Often involves lateral maxillary wall

Often the zygoma itself is intact
 Weaker bones and suture lines fracture
around zygoma
“Tetrapod”
SSD: Three of Four Attachments Disrupted
42M Punch to face
SSD: Fourth Attachment Disrupted
Zygoma Fractures

“Tripod” fractures
 Region of zygomaticofrontal suture
3D SSD: Comminuted Zygomatic Body
 Region of zygomaticotemporal suture
 Region of zygomaticomaxillary suture

“Tetrapod” fractures
 Zygomaticosphenoid suture
 Often involves lateral maxillary wall

Often the zygoma itself is intact
 Weaker bones and suture lines fracture
around zygoma
25M Car tire blew up in face
Zygoma Fractures
Preferred Term:
Zygomaticomaxillary complex fracture
Spectrum of zygomatic Injuries:
Isolated zygomatic
arch
Tripod
Tetrapod
Amount of Force
Comminution
of zygoma
ZMC Fracture
Rotation around the
zygomaticosphenoid
suture is possible even if
the upper transverse and
lateral vertical maxillary
buttresses are fixed
 Implications:

 Report suture disruption
 Review carefully on follow
up imaging
Transaxial CT: Zygomaticosphenoid Suture Disruption
Le Fort Fractures
Complex, multi-strut
 Dissociation of face from
skull base at anchor points
 Universally involve:

 Nasal apparatus
1
2
 Pterygoid processes
Classic Le Fort injuries are
uncommon
 Oversimplification but
useful to communicate and
to conceptualize injury

* Picture credit: Rosario Van Tulpe under GNU Free Documentation License v1.2
3
Simplified Approach
Fractured Structure
Significance
Pterygoid process
Le Fort almost always present
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Unique to Le Fort II
Zygomatic arch
Unique to Le Fort III
* Rhea and Novelline. How to Simplify the CT Diagnosis of Le Fort Fractures. AJR Am J Roentgenol. 2005 May; 184(5):1700-5
Simplified Approach
Fractured Structure
Significance
Pterygoid process
Le Fort almost always present
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Fractured
Structure
Zygomatic
arch
Unique to Le Fort II
Significance
Unique
to Le Fort III
Pterygoid
process
Coronal CT: Pterygoid Plate Fractures
Le
Fort almost always present
Transaxial CT: Pterygoid Plate Fractures
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Unique to Le Fort II
Zygomatic arch
Unique to Le Fort III
63M Fall
* Rhea and Novelline. How to Simplify the CT Diagnosis of Le Fort Fractures. AJR Am J Roentgenol. 2005 May; 184(5):1700-5
Simplified Approach
Fractured Structure
Significance
Pterygoid process
Le Fort almost always present
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Unique to Le Fort II
Zygomatic arch
Unique to Le Fort III
Coronal CT: Pterygoid Plate Fracture
Coronal CT: Nasal Fossa Fracture
* Rhea and Novelline. How to Simplify the CT Diagnosis of Le Fort Fractures. AJR Am J Roentgenol. 2005 May; 184(5):1700-5
SSD: Le Fort I
Simplified Approach
Fractured Structure
Significance
Pterygoid process
Le Fort almost always present
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Unique to Le Fort II
Zygomatic arch
Unique to Le Fort III
Coronal CT: Pterygoid Plate Fractures
Coronal CT: Inferior Orbital Rim Fracture
* Rhea and Novelline. How to Simplify the CT Diagnosis of Le Fort Fractures. AJR Am J Roentgenol. 2005 May; 184(5):1700-5
Simplified Approach
Fractured Structure
Significance
Pterygoid process
Le Fort almost always present
Lateral margin of nasal fossa
Unique to Le Fort I
Inferior orbital rim
Unique to Le Fort II
Zygomatic arch
Unique to Le Fort III
Coronal CT: Pterygoid Plate Fractures
Coronal CT: Zygomatic Arch Fractures
* Rhea and Novelline. How to Simplify the CT Diagnosis of Le Fort Fractures. AJR Am J Roentgenol. 2005 May; 184(5):1700-5
Le Fort Fractures: Pitfalls

SSD: Unilateral Le Fort I & II
Unilateral
 Requires a sagittal split of hard palate
 Results in widened maxillary arch

Combined Le Fort types
 Same side
 Different sides
 Don’t stop searching
Coronal: Left Pterygoid Plate Fracture
Coronal: Palate Fracture
27M Post-op internal fixation
Coronal: Nasal Fossa Fracture
Le Fort Fractures: Pitfalls

Unilateral
Coronal CT: Fractures Lateral Nasal Fossa Walls
 Requires a sagittal split of hard palate
 Results in widened maxillary arch

Combined Le Fort types
 Same side
 Different sides
 Don’t stop searching
Axial CT: Fractures of Pterygoid Plates
I
I
SSD: Fracture of Orbital Rim
61M Fall, head injury
II
Smash Fractures
High energy fractures
 Severe comminution
 Multiple fracture planes
 Multiple fracture
patterns
 Often associated with:

3D SSD: Facial Smash
 Intracranial injury
 Temporal bone fractures
 C-spine injury
66M Self-inflicted gunshot wound
Elements of: Zygomaticomaxillary Complex Fracture
65M Attacked by grizzly bear
Elements of: Naso-orbital Ethmoidal Fractures
65M Attacked by grizzly bear
Elements of: Orbital Blow Out
65M Attacked by grizzly bear
Elements of: Le Fort
65M Attacked by grizzly bear
Landmark
Significance
Medial orbital wall in
“simple” nasal fractures
• Likely NOE complex fracture
Nasofrontal duct
• Dysfunction leads to mucoceles
• May require frontal sinus obliteration
Lacrimal fossa
• Landmark for medial canthal tendon
attachment
Zygomaticosphenoid suture
• Watch out for rotatory deformity
Pterygoid plates
Orbital soft tissues
•
• Marker for transfacial injury
Next look at… lateral walls nasal fossa,
inferior orbital rims, zygomatic arches
•
• Widen windows
Look for foreign material