Spinal Fractures

Morphology
• Chalk stick fracture
• Spinal compression fracture
• burst fracture
• wedge fracture
• vertebra plana (mnemonic)
Fractures by location
• cervical spine fracture
• dens fracture
• extension teardrop fracture
• ​flexion teardrop fracture
• hangman fracture
• Jefferson fracture
• clay-shoveler's fracture
• thoracolumbar spine fracture
• Chance fracture
• transverse process fracture
• spondylolysis
• limbus fractures
• sacral fracture
• sacral insufficiency fractures

Chalk stick, also known as carrot stick
fractures, are fractures of the fused spine,
classically seen in ankylosing spondylitis
Chalk stick fractures are most commonly
encountered in ankylosing spondylitis but
may also been seen in the fused spines in
patients with 2:
• diffuse idiopathic skeletal hyperostosis
• ossification of the ligamentum flavum
• ossification of the posterior longitudinal
ligament
• surgical spinal fusion

Spinal compression fracture
• Spinal compression fractures occur
as a result of injury, commonly fall
onto the buttock or pressure from
normal activities, to the weakened
vertebrae due to osteoporosis.
• The vertebral fracture should be
diagnosed when there is a loss of
height in the anterior, middle, or
posterior dimension of the vertebral
body that exceeds 20%.
• Genant classification of vertebral
fractures based on vertebral height
loss as:
• mild: up to 20-25%
• moderate: 25-40%
• severe: >40%

Burst fracture
Burst fractures are a type of compression fracture
related to high-energy axial loading spinal trauma that
results in disruption of a vertebral body endplate and
the posterior vertebral body cortex. Retropulsion of
posterior cortex fragments into the spinal canal is
frequently included in the definition.
• loss of vertebral height on lateral views: anterior
portion is commonly compressed more than the
posterior portion of the vertebral body
• fracture always involves the posterior vertebral body
cortex
• burst vertebral body on axial CT
• vertical fracture through the posterior elements is
usually present in more severe trauma
• interpedicular widening
• bone fragment retropulsion into the spinal canal may
occur
• consequent spinal cord contusion may occur, and it is
best assessed by MRI (axial and sagittal T2)

Wedge fracture
• Spinal wedge (compression)
fractures are hyperflexion injuries
to the vertebral body resulting
loading.
• Radiographs, CT, and MRI may
disruption with impaction of one
without the involvement of the
wall 6. This results in the
"wedged" appearance

Vertebra plana
• Vertebra plana (plural:
vertebrae planae), also known
the pancake, silver
edge vertebra, is the term given
when a vertebral body has lost
entire height anteriorly and
representing a very advanced
fracture

Fractures by location
• cervical spine fracture
• dens fracture
• extension teardrop fracture
• flexion teardrop fracture
• hangman fracture
• Jefferson fracture
• clay-shoveler's fracture
• thoracolumbar spine fracture
• Chance fracture
• transverse process fracture
• spondylolysis
• limbus fractures
• sacral fracture
• sacral insufficiency fractures

Fractures by location
• cervical spine fracture
• dens fracture
• extension teardrop fracture
• flexion teardrop fracture
• hangman fracture
• Jefferson fracture
• clay-shoveler's fracture

Odontoid fracture
Odontoid process fracture, also known as a peg or dens fracture, occurs where there is a
fracture through the odontoid process of C2.
Classification Anderson and D'Alonzo
•type I
•rare
•fracture of the upper part of the odontoid peg (generally oblique)
•above the level of the transverse band of the cruciform ligament
•usually considered stable
•type II
•most common
•transverse course fracture at the base of the odontoid
•below the level of the transverse band of the cruciform ligament
•unstable
•high risk of non-union
•type IIa
•​type II fractures with comminution at the odontoid base
•Hadley 2 described this type of fracture which has a significantly increased risk of nonunion when
classical type II fractures
•represents 5-10% of type II fractures
•type III
•through the odontoid and into the lateral masses of C2
•relatively stable if not excessively displaced
•best prognosis for healing because of the larger surface area of the fracture

Extension teardrop fracture
Extension teardrop fracture typically occurs due to forced
extension of the neck with resulting avulsion of the
vertebral body
anterior-inferior corner fracture 3
• avulsion fracture from the attachment of the anterior
inferior corner of the vertebral body, usually a thin fracture
• the fragment is triangular in a shape reminiscent of a teardrop
• vertical height of fragment is equal to or greater than width
• anterior disc space widening

Flexion teardrop fracture
Flexion teardrop fractures represent a fracture pattern occurring in
severe axial/flexion injury of the cervical spine.
Flexion teardrop fractures most commonly occur at the mid/lower
at C4, C5, or C6 1,2.
• The most characteristic findings include:
• fracture of the anteroinferior lip of vertebral body
• classically a triangular fragment (teardrop sign)
• larger fragments may not appear triangular
• anterior fragment often minimally displaced
• posterior displacement of the posterior vertebral body relative to
column
• evidence of posterior ligamentous rupture

Hangman fracture
Hangman fracture, also known as traumatic spondylolisthesis of
the axis, is a fracture which involves the pars
interarticularis of C2 on both sides, and is a result of
Radiography and CT demonstrate the findings:
• typical: bilateral C2 pars interarticularis fractures
• atypical variant: one or both sides of C2 has a coronal plane
fracture through the posterior vertebral body instead of the
• possible alignment abnormality: anterolisthesis of C2 on C3 or
• Extension of the fracture to the transverse foramina should be
possibility of vertebral artery injury.

Jefferson fracture
Jefferson fracture is the eponymous
name given to a burst fracture of
originally described as a four-part
double fractures through the anterior
arches,
Radiographs will show asymmetry in
view with the displacement of the
away from the odontoid peg (dens). A
greater than 6 mm suggests

Jefferson fracture
• type 1: fractures of the anterior arch
• type 2: fractures of the posterior arch and are
usually bilateral
• type 3: fractures involving the anterior and
posterior arch (Jefferson burst fracture)
• type 3a: intact transverse atlantal ligament
• type 3b: disrupted transverse atlantal ligament
complex
• Dickman type 1: ligamentous disruption
• Dickman type 2: bony avulsion with an intact transverse
atlantal ligament
• type 4: fractures of the lateral mass
• type 5: isolated fractures of the C1 transverse
process

Clay-shoveler fracture
Clay-shoveler fractures are fractures of the spinous
process of a lower cervical vertebra.
The fracture is seen on lateral radiographs as an oblique
spinous process, usually of C7. There is usually significant

Fractures by location
• thoracolumbar
fracture
• Chance fracture
• transverse process
fracture
• spondylolysis
• limbus fractures

Chance fracture
Chance fractures also referred to as seatbelt fractures, are flexion-
distraction type injuries of the spine that extend to involve all three
unstable injuries and have a high association with intra-abdominal
Anterior wedge fracture of the vertebral body with a horizontal
elements or distraction of facet joints and spinous processes.
• empty vertebral body sign: can be seen on an AP radiograph and
separation of the posterior elements displacing the spinous
fracture fragments of the vertebral body on the AP projection
• transverse fractures across the transverse processes, laminae, and
• widening of the interpedicular distance: often suggests a burst
• widening of the facet joints and increased intercostal spacing
• widening of the interspinous spaces

Transverse process fracture
Transverse process fractures are common sequelae of
trauma, although they are considered minor and
Transverse process fracture most commonly occurs in the
spine and are commonly multiple 2. The fracture line can
the transverse foramen, and in the cervical spine, there is a
complicating vertebral artery dissection.

Spondylolysis
Spondylolysis is a defect in the pars interarticularis of the
neural arch, the portion of the neural arch that connects
articular facets. It is commonly known as pars
simply as pars defect.
• Scotty dog sign: on oblique radiographs, a break in the
can have the appearance of a collar around the dog's neck
• inverted Napoleon hat sign

Posterior ring apophyseal fracture
Posterior ring apophyseal fracture or separation, also called limbus fracture, occur in the
immature skeleton, most commonly in the lumbar spine. They represent bony fractures of
of attachment of the Sharpey fibers of the intervertebral disc.
They can be classified as follows:
• type I: avulsions of the posterior cortical vertebral rim
• type II: central cortical and cancellous bone fractures
• type III: lateralized chip fractures
• type IV: span the entire length and breadth of the posterior vertebral margin between the
endplates
CT
• CT is excellent for bony detail and is therefore usually the first line imaging modality.
• osseous fragment displaced posteriorly to endplate with rectangular or arc-shaped
• posterior endplate defect
• posterior disc herniation

• Sacral fracture
• sacral
fractures

Sacral insufficiency fracture
Sacral insufficiency fractures are a subtype of stress fractures, which
are the result of normal stresses on abnormal bone, most frequently
of osteoporosis. They fall under the broader group of pelvic
Plain radiograph
• They may be normal, or a sclerotic line may be noted in the
CT
• May show a fracture line along with sclerosis that is parallel to the
even CT imaging is less sensitive as compared to MRI and nuclear
MRI
• Can depict bone marrow edema as early as 18 days after the

Le Fort fracture classification
Le Fort fractures are fractures of the midface, which collectively
involve separation of all or a portion of the midface from
• Le Fort type I
• horizontal maxillary fracture, separating the teeth from the upper
• fracture line passes through the alveolar ridge, lateral nose and
the maxillary sinus
• also known as a Guerin fracture
• Le Fort type II
• pyramidal fracture, with the teeth at the pyramid base, and
• fracture arch passes through the posterior alveolar ridge, lateral
sinuses, inferior orbital rim and nasal bones
• uppermost fracture line can pass through the nasofrontal junction
the maxilla 3
• Le Fort type III
• craniofacial disjunction
• transverse fracture line passes through nasofrontal
wall, and zygomatic arch/zygomaticofrontal suture
• because of the involvement of the zygomatic arch, there is a risk
impingement
• unsurprisingly type III fractures have the highest rate of CSF leak

1 Column - Anterior compression injury
Anterior compression injury is a common fracture pattern which results from traumatic hyper-flexion with compression.
Although considered 'stable' the greater the loss of height anteriorly the greater the risk of middle column involvement.
X-ray may underestimate the extent of injury and so if there has been high risk injury or other suspicion of instability then
CT should be considered.

2 column - 'Burst' fracture
'Burst' fractures result from high force vertical compression trauma. Posterior displacement of vertebral body
fracture fragments into the spinal canal leads to a high risk of spinal cord or nerve root damage.