There is no scientifically admissible evidence to support use of routine MRI as a screening tool in cervical trauma.33
There is strong evidence to suggest that use of routine cervical spine radiographs alone (compared to CT scans) may miss important injuries in the evaluation of patients with traumatic, high-risk neck injuries in emergency situations, and that CT scan should be used instead.31
Even when using a three-view X-ray series, there is evidence of missed injuries in up to 57% of high-risk patients and in 7–35% of patients overall. Additionally, the three-view series can be difficult to obtain, with reports of inadequate visualisation in 50–80% of initial and 25% of repeat radiographs.43
However, flexion–extension X-rays are still an important tool in the assessment of patients with cervical spine injuries, and may be useful in excluding dynamic instability, particularly in those patients who have sustained a significant ligamentous injury and no fracture.
CT scans have better validity than radiographs in assessing high-risk and/or multi-injured blunt trauma neck patients.31 There is evidence that CT should be the preferred imaging modality, replacing plain films in the initial evaluation of suspected cervical spine injuries.43
CT is superior to MRI in identifying bony injuries such as osseous fracture, vertebral subluxation/dislocation and locked facets.37
Modern CT alone is sufficient to detect unstable cervical spine injuries in trauma patients. Adjuvant imaging is unnecessary when the CT scan is negative for acute injury.44
MRI is not suitable for detecting fracture.
MRI is superior at identifying soft tissue injuries, such as spinal cord injury and ligamentous injury.37 MRI is preferred for evaluating possible ligamentous injuries in acute cervical spine trauma and possible spinal cord injury.39
Note that role of MRI in evaluating ligamentous and membranous abnormalities in patients with whiplash-associated disorders is controversial.45 There is evidence that MRI may not demonstrate soft tissue lesion in acute whiplash injury. MRI has been shown to reveal changes in the ligaments of the upper cervical spine in late stage whiplash injury; however, these findings may not be clinically significant, nor do they assist with treatment planning.31,45
MRI should be limited to patients in whom other studies are contraindicated or if the imaging fails to adequately clear the patient for suspected fracture.46
MRI is not required to clear the spine (rule out fracture) if a radiologist has reported a negative CT.44