Download Xray Rounds- CLEARING THE C-SPINE

Xray Rounds- CLEARING THE C-SPINE
Gaetano P. Monteleone, Jr., M.D.
Dept of Family Medicine
Division of Sports Medicine
West Virginia University School of Medicine
I.
Standard C-spine series:
Anteropasterior (AP) view
Lateral (cross-table) view
Open mouth view (Fuch's, Water’s)
II.
Additional views:
Obliques
Lateral flexion/extension
Swimmer's view
III.
Injuries: Fractures, instability (ligaments),
cervical stenosis
IV.
General
A.
In children, cervical spine injuries
generally affect C1, C2 or the atlanto-occipital
articulation. In adults, most injuries involve C3 C7.
V.
Some Specifics
A.
Lateral view- this is the most
important view. All seven cervical vertebrae and
the superior portion of the first thoracic
vertebra must be visualized before proceeding.
If these vertebrae are not seen, repeat lateral with
downward traction on the arm or obtain the
swimmer's view (humerus in 170-180° forward
flexion).
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Four lines should be roughly parallel:
anterior and posterior vertebral bodies, spinolaminar line and the spinous process line.
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Atlantodens interval (ADI) < 3 mm adults ( < 5mm, children). Distance between atlas
and dens of the axis. AKA atlantoaxial interval. 3-5mm = torn transverse ligament and
possible atlantoaxial instability; Atlantoaxial dislocation more common in rheumatoid
arthritis and Downs .
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The retropharyngeal space (B) in upper vertebrae should not exceed 7 mm, may be
indirect evidence for injury. Similarly, the prevertebral fat stripe (C) should not be
blurred or displaced.
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Disc spaces should be maintained, facet joints and interspinous distances should be
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Xray Rounds- CLEARING THE C-SPINE
Gaetano P. Monteleone, Jr., M.D.
Dept of Family Medicine
Division of Sports Medicine
West Virginia University School of Medicine
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symmetrical. Assymetry of interspinous
distances may reflect rupture of posterior longitudinal ligament.
Vertebral body height should be checked.
Vertebral canal measurements: normal > 13 mm, usually measured at C5 typically the
most narrow part of the canal. Because of magnification factors and radiographic
technique, a ratio method described by Torg and Pavlov was also suggested. Ratio of a
(measure posterior vertebral body to spinolaminar line) to b (measure width of vertebral
body). a/b < 0.80 suggestive of cervical spinal stenosis. Cantu, Herzog, Odor and
others find this ratio method inaccurate in diagnosis of spinal stenosis. The ave. AP
diameter of the canal is ≈ 22 mm at C1, 20 mm at C2, and 17 mm at C3 - C7. Studies have
demonstrated the normal sagital diameter of the spinal cord ranges from ≈ 0.5 to 11.5
mm. Proposed that more important to assess "functional" cervical spinal stenosis via
MRI. MRI may demonstrate impingement of the cord, ablation of the normal CSF fluid
around the cord.
B.
AP view: offers less information than lateral view.
Parallel lines at spinous processes and pedicles.
Disc spaces equal and maintained.
Vertebral bodies checked for fracture.
C.
Open-mouth view (Fuch's):
Odontoid fractures-the overlapping
shadows of base of skull and incisor
teeth may simulate fx.
Lateral masses- Medial aspect of C1
lateral masses should be equidistant
to the odontoid. In addition, these
lateral masses should be perfectly
aligned with lateral masses of C2. The
normal distance between C1 lateral
masses is < 7mm (figure 5). If greater distance, indicates ruptured transverse ligament
or Jefferson fx (burst fx of C1). 1 A Water's view also looks at the odontoid from under
chin to vertex of head.
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Jefferson fx is usually NOT associated with severe neurologic deficits and may not be
obvious at first glance.
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Xray Rounds- CLEARING THE C-SPINE
Gaetano P. Monteleone, Jr., M.D.
Dept of Family Medicine
Division of Sports Medicine
West Virginia University School of Medicine
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D.
Additional views:
Lateral flexion/extension views- Have patient actively flex and extend neck to obtain
this view. Severe hyperflexion may produce injury to disruption of posterior ligaments.
Hyperextension may produce teardrop fx2 (figure 18) or anterior ligament injury. Check
angle produced by lines drawn at inferior vertebral bodies of two adjacent vertebrae.
Angle > 11° indicates ligamentous instability. Instability also demonstrated with
horizontal translation of one vertebral body on another of > 3.5 mm.
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Teardrop fx involves the anteroinferior portion of the vertebral body with
hyperextension. Most commonly affects C2.
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