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A 42-year-old man was the front seat passenger in a car that
was struck on the driver’s side by another vehicle. Neither
car was going at high speed. Damage to the patient’s car
was limited to the front fender; the windshield was not “spidered.” The
patient was wearing a seat belt at the time of the collision. He
was brought to the ED in full spine immobilization and was triaged
to one of the examination rooms.
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The patient was awake and alert with no overt signs of trauma.
His vital signs were normal. He complained of pain in his neck,
lower back, and right wrist. He noted that he had struck his head on
the car door and had been “dazed” for a few seconds,
but was uncertain whether he had lost consciousness.
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On examination, he had mild midline neck tenderness without deformity.
There were good bilateral breath sounds without chest wall tenderness.
His abdomen, pelvis, and extremities showed no signs of injury.
The neurological examination was normal.
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The patient was removed from the “long board” and
sent for cervical spine radiography. The radiographs are shown in
Figure 1.
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- Are there any abnormalities?
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Although ABCS (alignment, bone,
cartilage, and soft tissues) is a convenient mnemonic device for
the interpretation of the lateral cervical spine radiograph, one
element seen on the lateral view is not emphasized in this scheme–alignment
of the articular facets and lateral masses of C3–C7.
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Each vertebra has two lateral masses and each lateral mass has
a superior and inferior articular facet. On the lateral view, each
lateral mass has a diamond shape formed by the superior and inferior
articular facets and the anterior and posterior cortical surfaces.
In a perfectly positioned lateral view, the left and right lateral
masses are exactly superimposed. More often, the patient’s positioning
is slightly rotated and the lateral masses are not exactly superimposed
(Figure 2).
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In this patient’s lateral view (Figure
1), the positioning is slightly rotated and the articular facets
do not exactly overlap. However, at C3 there is an ...