Backache in a 16 Year Old
Radiology Cases in Pediatric Emergency Medicine
Volume 6, Case 13
Abu N.G.A. Khan, MD
Maimonides Medical Center
Peter S. Dayan, MD
Columbia Presbyterian and Babies Hospital
Columbia College of Physicians and Surgeons
A 16 year old athletic female walked into the
pediatric emergency department with a history of falling
down 14 stairs, landing on her back. She complained
solely of pain in the lower back. She denied any head
trauma, loss of consciousness, vomiting, abdominal
pain, or difficulty on urination. She had no past history
of trauma to the back and had never been hospitalized.
Exam: She is alert and active but uncomfortable
secondary to back pain. She is able to ambulate
without any support. No neurologic deficit is noted on
Back examination: No focal tenderness over the
lumbo-sacral spine noted. Mild to moderate tenderness
over the right paraspinal region. No CVA tenderness,
no abdominal tenderness. No bruises or echymoses.
She is felt to have a soft tissue injury of her back.
Although there is a low suspicion for fracture,
lumbo-sacral radiographs are ordered.
Interpretation: The L2 vertebra shows some loss of
height of the anterior vertebral body. The posterior
vertebral line is intact. A compression deformity of
L2 is suspected. A CT scan is ordered to examine the
extent of injury.
View CT scan.
CT Scan: Multiple 5-mm continuous axial sections
of the lumbo-sacral spine were obtained from the upper
border of L1 to the level of S3 without intravenous
contrast. Serial cuts of L2 are shown here (cuts 7, 8
and 9 shown left, right and bottom, respectively) There
is a wedge compression deformity of L2 vertebral body
with preservation of the disc spaces above and below
this level. There is minimal retropulsion of the L2 body
not causing any significant compression of the thecal
sac. The superior end plate and part of the body
appear fragmented as seen on image cuts 7, 8 and 9.
There is minimal prevertebral soft tissue prominence.
The bony spinal canal is normal in size and
configuration. No significant posterior bulging or
herniation of the disc is present.
Hospital Course: She was hospitalized under the
neurosurgery service for observation and discharged
home in two days with a brace.
Thoraco-lumbar fractures are a major cause of
disability (1). Ninety percent of all spinal fractures are
in the thoraco-lumbar region. Fractures at the
thoraco-lumbar junction have a significant incidence of
neurologic deficit of up to 40% in one series (2).
Several factors contribute to thoraco-lumbar
a. In the lumbar spine , there are no ribs to provide
additional stability as in the thoracic region (3).
b. The alignment of the spine changes from a
kyphotic curvature in the thorax to a lordotic alignment
in the lumbar spine (4).
c. Lumbar spinal segments are more mobile than
thoracic segments. The mobility is due in part to the
changing orientation of the facet joints. The coronal
orientation of the facets in thoracic region is more
stable then the oblique orientation of the lumbar region.
The Three Column Concept
The management and outcome of lumbosacral spine
injuries largely depend upon the stability of the spinal
column. There are different models to describe the
stability following an injury. The three-column concept
described by Denis (5,6) in 1983 is the most accepted.
View three-column diagram: Fig1
Fig.1: Lateral View of Lumbo-sacral Vertebrae
1. The anterior column consists of the anterior
longitudinal ligament and the anterior part of the
2. The middle column extends from the middle
portion of the vertebral body to the posterior aspect of
the vertebral body and includes the posterior
3. The posterior column includes all bony and
ligamentous structures posterior to the posterior
longitudinal ligament and includes the pedicles, facets,
spinous processes and all associated ligaments.
Fractures involving only the anterior columns are
considered stable, while fractures that involve the
middle or all three columns are considered unstable.
Types of Thoraco-lumbar Fractures
Thoraco-lumbar fractures and dislocations have
been classified by different investigators (1,4).
However, no one classification system is inclusive of all
injury patterns. Currently the classification described by
McAfee, et al. (7), is the most widely recognized. Their
TLS injury scheme consists of five distinctive injury
patterns: wedge compression fractures, burst
fractures, Chance fractures, flexion-distraction injuries
and translational injuries (see Fig 2). In recent years,
the increased use of magnetic resonance imaging
(MRI) and helical CT scanning has led to improvements
in classifying TLS injuries.
View TLS injury types: Fig2
Fig. 2: Types of thoraco-lumbar fractures
1. Wedge compression fractures are the most
common type of lumbar fracture (4). They occur during
hyperflexion and axial loading (as was likely in our
case). The vertebral body fails under a compressive
load and its anterior portion becomes compressed while
the middle column remains intact. This fracture is
rarely associated with neural injury unless multiple
adjacent vertebral bodies are compressed.
Radiographically, the wedge deformity is best
appreciated on the lateral view. A CT scan is used to
confirm that the posterior vertebral body, pedicles and
lamina are intact.
2. A burst fracture of the spine was first described
by Holdsworth (8) in 1963 and redefined by Denis (6) in
1983 as being a fracture of the anterior and middle
columns of the spine with or without an associated
posterior column fracture. Both a compression fracture
and burst fracture occur during hyperflexion and axial
loading of a vertebra. With a burst fracture, however,
there is compression of the vertebra and intervertebral
disk in such a fashion that the compressed disk
adjacent to the affected vertebra herniates into the
vertebral body. As a result, the vertebra fractures
outward with retropulsion of bone fragment into the
spinal canal and an increase in interpeduncular
distance (distance between the pedicles). Because all
burst fractures have the potential for severe neurologic
sequelae, they should be considered unstable during
the initial emergency department evaluation. Unstable
burst fractures are treated with surgical stabilization to
improve long-term alignment. For stable fractures, the
neurologic outcome may be similar for surgically and
non-surgically treated patients (1,4).
3. A Chance fracture is commonly associated with
lap seat belt use in high-speed motor vehicle crashes
(9). A Chance fracture is a horizontal vertebral injury
that results from flexion about an axis that is anterior to
the anterior spinal longitudinal ligament. This vector of
force results in the horizontal disruption of the spinous
process, lamina, transverse processes, pedicles and
the vertebral body. A lateral radiograph best illustrates
the split in the posterior arch and vertebral body. More
subtle signs include an increase in adjacent spinous
process distancec above and below the injury and an
increase in the height of the posterior vertebral body.
An anterior-posterior radiograph may demonstrate the
split in the transverse processes. Since the fracture
runs in an axial plane, a routine axial CT scan may miss
a Chance fracture. It is important to perform the
reconstruction in the sagital plane to detect the fracture
and any malalignment due to ligamentous injury.
4. A flexion distraction injury is one in which the axis
of flexion is posterior to the anterior spinal longitudinal
ligament. There is compressive failure of the anterior
column and destructive forces placed on the middle and
posterior columns lead to a tear of the posterior
longitudinal ligament. Typically, these injuries involve
both ligamentous and bony structures and can extend
over more than one vertebral level. These injuries are
considered unstable because the middle column and
often the posterior column are disrupted. Radiographic
findings include anterior impaction with compression
fracture of the vertebral body and posterior distraction
with fanning of the spinous processes.
5. Translational injuries are associated with
shearing forces that disrupt all three columns. The
shearing forces are most often directed posteriorly to
anteriorly but may also be directed anteriorly to
posteriorly. Since the ligament of the spinal canal is
affected, these injuries are always unstable and are
associated with a very high incidence of neurologic
deficit (6). Lateral radiographs demonstrate anterior
translation of the upper vertebrae with respect to the
lower vertebrae. On the AP radiograph, the
interspinous distance at the affected level is widened
and there may or may not be a rotational malalingment
of the vertebra. CT scan may show "naked facets" or a
double vertebra, if the dislocation is severe.
Thoraco-lumbar spine injuries are common and
often result in serous morbidity. Forty-seven percent of
patients with spine trauma and 64% with spinal cord
injuries have concomitant injuries elsewhere (10). In
the setting of multiple trauma, in which most TLS
injuries occur, strict spinal cord injury precautions must
be observed until injury has been ruled out. A working
knowledge of spinal column anatomy is crucial to
evaluate and manage these injuries. Application of
Denis' three-column model to assess spinal stability
and McAfee's classification of fracture/dislocation
facilitate management decisions.
1. Kraemer WJ, Schemitsch EH, Lever J, McBroom
RJ, McKee MD and Waddell JP. Functional outcome of
thoraco-lumbar burst fracture without neurological
deficit. Journal of Orthopedic Trauma
2. Frankel HL, Rozycki GS, Ochsner MG, et al.
Indications for obtaining survillance thoracic and lumbar
spine radiographs. J Trauma 1994;37:673-676.
3. Kaye JJ, Nance EP. Thoracic and lumbar spine
trauma. Radiol Clin North Am 1990;28:361-377.
4. Brandser EA, Ei-Khoury GY. Thoracic and
lumbar spine trauma. Radiol Clin North Am
5. Denis F. Spinal instability as defined by the three
column spine concept in acute trauma. Clin Orthop
6. Denis F. The three column spine and its
significance in the classification of acute thoracolumbar
spinal injuries. Spine 1983;8:817-831.
7. McAfee PC, Yuan HA, Fredrickson BE, et al.
Value of computed tomography in thoraco-lumbar
fracture: An analysis of one hundred consecutive
cases and a new classification. J Bone Joint Surg
8. Holdsworth FW. Fractures, dislocations and
fracture/dislocation of the spine. J Bone Joint Surg
9. Savitsky E, Votey S. Emergency department
approach to acute thoracolumbar spine injury. J
Emerg Med 1997;15(1):49-60.
10. Saboe LA, Reid DC, Davis LA, et al. Spine
trauma and associated injuries. J Trauma
Return to Radiology Cases In Ped Emerg Med Case Selection Page
Return to Univ. Hawaii Dept. Pediatrics Home Page