Laboratory Studies
Laboratory studies are not typically useful in the diagnosis of cervical spine injuries.
Imaging Studies
Plain radiography
Historically providers would obtain plain radiographs when cervical injury is suspected. Plain radiographs are still useful, but are being replaced by the availability and performance of CT. Two large studies looked at when radiographs should be obtained. The criteria for radiography differ, and some controversy remains regarding which system is better. [20, 21, 22] Keep in mind as well that these studies were not focused on athletes or athletic mechanisms of injury. Use of these guidelines should be taken with precaution in athletes.
According to the National Emergency X-Radiography Utilization Study (NEXUS) study criteria, the patient must exhibit the following criteria in order for the mechanism and dynamics of injury to be considered low risk, and, if any of the below criteria are present, radiographs should be obtained [23] :
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No posterior midline cervical spine tenderness
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No evidence of intoxication
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Normal level of alertness
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No focal neurologic deficit
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No painful distracting injuries
The Canadian C-Spine Rule (CCR) uses more criteria to determine who should undergo radiographs [21, 24, 25] :
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Primary criteria – First, take the following into consideration: (1) patient age older than 65 years, (2) mechanism of injury considered dangerous, and (3) numbness or tingling present in the extremities.
A dangerous mechanism of injury would be, for example, a fall from an elevation of 3 feet or higher, a bicycle collision, an axial load to the head (eg, resulting from a dive into an empty swimming pool), or a motor vehicle collision involving high speed, rollover, or ejection.
If any of these high-risk factors is present, then the patient is at risk for having a cervical spine injury and neck radiography should be performed.
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Additional criteria: If the patient does not meet any of the above criteria, then the question becomes whether the patient is voluntarily able to actively rotate the neck 45° in each direction.
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NOTE: Before any neck rotation test is performed, at least one of the following low-risk factors must be present: (1) simple rear-end motor vehicle collision, (2) patient ambulatory at any time since injury, (3) delayed onset of neck pain, (4) patient in sitting position in emergency department, or (5) absence of midline cervical spine tenderness. If none of these criteria is met, radiography should be performed.
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Finally, if the athlete is unable to voluntarily rotate to 45° in each direction, radiography should be preformed.
The standard radiographs obtained in a cervical spine series vary slightly by facility. Usefulness of some views in routine radiographic screening has been debated. A large patient study indicated that standard 3-view imaging is reliable for screening trauma patients. [26]
The 3-view series includes cross-table lateral, anteroposterior, and open-mouth odontoid views. Additional radiographic views include oblique views, odontoid tip shots, swimmer's view, and flexion/extension views. [27, 28, 29]
Computed tomography (CT) scanning
Perform CT scanning after plain radiography to further evaluate abnormalities. [30] CT scanning is also useful in the evaluation of areas that are difficult to evaluate or see in plain radiographs, such as the lower cervical spine in very large individuals secondary to body habitus. CT scanning is often replacing plain radiographs in many facilities.
CT scanning provides much greater visualization of fractures and the capability to form 3-dimensional (3-D) reconstructions of the vertebrae, which may be helpful preoperatively. CT imaging is preferable in the obtunded patient and may facilitate the evaluation of the unstable spine in these patients. [31]
CT scanning has become the study of choice for unconscious patients and for those with abnormal plain radiographs. In some institutions, this imaging modality has replaced plain radiographs for most presentations. There is a greater exposure to radiation with this modality and this should be considered as well.
Magnetic resonance imaging (MRI)
MRI serves best in evaluating the soft structures of the spinal column.
MRI is helpful in the evaluation of ligamentous injuries and neural tissue.
MRI is helpful in the evaluation of spinal stenosis.
MRI assessments after spinal cord injury correlate with patient neurologic status and are predictive of outcome at long-term follow-up. [32]
In patients with persistent midline cervical tenderness and negative CT findings, MRI is not predictive of 12-month outcomes, including long term neck disability and time to return to work. [33]
Bone scanning
Bone scanning may be of assistance in the evaluation of stress fractures, infections, and tumors.
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Anteroposterior view of atlantooccipital dislocation.
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Odontoid view of a Jefferson fracture.
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Lateral view of a C2 fracture dislocation.
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Odontoid type 2 fracture.
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Lateral view of type 3 odontoid fracture.
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Computed tomography scans of odontoid type 3 fracture.
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Lateral view of a C3 spinous fracture.
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Lateral view of hangman's fracture.
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C3 flexion fracture.
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C4 burst fracture.
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Clay shoveler's fracture.
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Unilateral locked facets on C5 and C6.
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Bilateral facet fracture/dislocation at C6/C7.
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Child with C6 flexion wedge fracture.
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C7 lamina fracture.
