Laboratory Studies
Routine laboratory studies for trauma patients are included for those with subaxial cervical spine trauma. A complete blood count (CBC), urinalysis, and serum electrolyte levels and chemistries are obtained as the individual case dictates.
A blood type and screen or crossmatch for packed or whole blood may be necessary, depending on the concomitant injuries and vital sign assessment.
When spinal cord injury (SCI) is present, neurologic impairment may impede evaluation of other injuries, including intra-abdominal trauma to solid organs. Liver and renal function testing may be of benefit in these situations.
Imaging Studies
The cross-table lateral radiograph (see the image below) has been the criterion standard for evaluating subaxial cervical alignment. This must include visualization of the cervicothoracic junction. A swimmer's view may be necessary to complete the evaluation of this area, but if body habitus precludes adequate visualization, computed tomography (CT) of the area is mandatory to exclude neck injury. Additional views include the anteroposterior (AP) and open-mouth odontoid radiographs. [13, 14]
Whereas a CT scan is helpful in imaging the cervicothoracic junction, it is extremely beneficial in identifying posterior-column injuries such as lamina or facet fractures. [15] (See the images below.)
Guidelines published in 2013 by the Congress of Neurological Surgeons did not recommend radiography of the cervical spine for awake, asymptomatic patients who have no neck pain or tenderness, whose neurologic examination is normal, who do not have an injury that would hinder accurate evaluation, and who can complete a functional range of motion examination. [16] High-quality CT of the cervical spine is recommended for the awake, symptomatic patient, with a three-view spine series recommended if high-quality CT imaging is not available.
Magnetic resonance imaging (MRI) is particularly useful in demonstrating injuries to the neural elements, especially the spinal cord. Traumatic disk herniations are well delineated on MRI, but routine use of this study may not contribute to the treatment regimen chosen for these injuries. If the neurologic level of injury does not match the area of injury identified by standard radiographs, this is another indication for MRI. (See the image below.)
Some have found MRI of the cervical spine to be helpful in determining ligamentous injury, but its application to justifying surgical intervention is not clear from available literature. MRI may fail to detect traumatic discoligamentous injuries to the subaxial cervical spine that are later discovered during surgery, especially in patients with preexisting degenerative cervical spondylosis. [17]
There is controversy on the management of unilateral and bilateral facet dislocations, because neurologic deterioration has been reported after closed reduction. Eismont suggested that the mechanism of this deterioration is cord compression at the time of reduction by large associated disk herniations. [18] He recommended that MRI be done before reduction and proposed that if a large disk herniation is found, anterior removal should be done before reduction so as to avoid a catastrophic event. This approach, however, remains debatable; some surgeons believe that reduction should not be delayed in a neurologically incomplete or deteriorating patient but should be performed on an urgent basis.
If the patient is neurologically intact and alert, it seems reasonable to perform MRI if this is not otherwise contraindicated. Each clinical situation must be assessed individually. In the patient with multiple injuries, including life-threatening injuries that require stabilization in the operating room, reduction could be performed without the delay necessary to obtain an MRI scan.
Magnetic resonance angiography (MRA) may be indicated when associated vertebral artery injury is suspected. This may occur in the severely degenerative cervical spine or when fractures through the foramina transversarium are present.
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Cross-sectional anatomy of the cervical cord.
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Normal anatomy of the lower cervical spine.
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Lateral film of a C5 burst/teardrop fracture.
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Sagittal CT scan of C5 burst fracture.
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Axial CT scan of C5 burst fracture.
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Reduction of C5 burst fracture after tongs traction.
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Postoperative image of C5 burst fracture; note anterior and posterior fixation.
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Postoperative image of C5 burst fracture.
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Standard lateral cervical spine of an 80-year-old patient after a motor vehicle accident; patient has no neurologic deficits and no neck pain.
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Swimmer's view of the same 80-year-old patient as in Image 9; note the C7-T1 fracture/dislocation.
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Axial CT scan of C7-T1 fracture/dislocation.
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Sagittal CT of C7-T1 fracture/dislocation.
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MRI of C7-T1 fracture/dislocation.
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Reduction of C7-T1 fracture/dislocation.
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Postoperative anteroposterior view of C7-T1 fracture/dislocation.
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Postoperative lateral view of C7-T1 fracture/dislocation.
