Pediatric emergency medicine trisk 901
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FIGURE 112.21 A: Gardner–Wells tongs. B: Halo traction brace. Unstable cervical spine
injuries may require immediate placement of semipermanent immobilization devices. These
should be administered only by those experienced in appropriate usage and application.
SPECIFIC INJURIES
Jefferson Fracture
A Jefferson fracture is a bursting fracture of the ring of C1 as a result of an axial
load. The ring of C1 is compressed between the occipital condyles of the skull and
the lateral masses of C2. This process can cause an outward burst of C1, but it
rarely causes immediate neurologic impairment because the fracture does not
physically impinge on the spinal cord. The radiographic criterion for the diagnosis
of a Jefferson fracture is lateral offset of the lateral mass of C1 of more than 1 mm
from the vertebral body of C2 ( Fig. 112.22 ). Neck rotation may give a falsepositive radiographic finding. These fractures may be unstable, however, and
require adequate immobilization. If the transverse ligament is intact, the fracture
may be relatively stable, whereas if the transverse ligament is injured and there is
an increased distance between the lateral masses and the odontoid process, it
should be considered unstable. A reduced AP diameter of the cervical spinal canal
is also associated with spinal cord injury. Approximately one-third of Jefferson
fractures are associated with other cervical spine fractures, most often involving
C2. The clinician must be aware of the pseudo-Jefferson fracture of childhood,
which is present in 90% of children at 2 years of age and usually normalizes by 4
to 6 years of age. The pseudo-Jefferson fracture has the radiographic appearance
of a Jefferson fracture because of increased growth of the atlas (C1) compared
with the axis (C2) and radiolucent cartilage artifact. This disorder can present with
unilateral or bilateral lateral mass offset. If a Jefferson fracture is suspected by
radiographic findings and mechanism of injury in children younger than 4 years, a
CT scan may be necessary to further elucidate the suspected injury ( Fig. 112.23 ).
FIGURE 112.22 A: Normal anteroposterior (AP) (open-mouth, odontoid) view of C1 and C2. C
1 , first cervical vertebra (lateral mass); C 2 , second cervical vertebra; T, central incisors
overlying dens (D ); and A, normal relationship between lateral mass of C1 and vertebral body
of C2. B: Jefferson fracture in AP view. Note lateral offset of C1 on C2 (arrows ). C: Jefferson
fracture. Computed tomography coronal view. Note three distinct fractures (arrows ) and
bursting nature of injury. D: Pseudo-Jefferson fracture of childhood in a 3-year-old child
because of disparate growth of C1 and C2 and cartilage artifact (arrows ). E: Pseudo-Jefferson
fracture demonstrating marked offset of the lateral masses of C1 on C2 (arrows ). (B , C :
Reprinted with permission from Swischuk L. Emergency Radiology of the Acutely Ill or Injured
Child . 2nd ed. Baltimore, MD: Williams & Wilkins; 1986:591. D : From Aslamy W, Danielson
K, Hessel S, et al. A 3-year-old boy with neck pain after motor vehicle accident. West Med J
1991;155(3):301–302. Copyright BMJ Publishing Inc. Reprinted with permission.)
FIGURE 112.23 A: Apparently “normal” lateral cervical spine radiograph (16-year-old patient
after motor vehicle accident). B: Spiral computed tomography (CT) scan demonstrating dens
fracture (arrow ). C: Sagittal view of spiral CT scan demonstrating dens fracture (arrow A ) and
vertebral body avulsion fracture (arrow B ). The detail demonstrated by the spiral CT scan could
help clinicians quickly identify lesions not easily visible or appreciated on conventional
radiographs.
Hangman’s Fracture
The hangman’s fracture is a traumatic spondylolisthesis of C2. This injury occurs
as a result of hyperextension, which fractures the posterior elements of C2.
Hyperflexion, with resultant ligamentous damage, may follow the hyperextension
or may lead to anterior subluxation of C2 on C3 and subsequent damage of the
cervical cord ( Fig. 112.24 ). The subluxation associated with a hangman’s
