Is magnetic resonance imaging becoming the new computed tomography for cervical spine clearance? Trends in magnetic resonance imaging utilization at a Level I trauma center.

Background: Increasing evidence supports the limited use of magnetic resonance imaging (MRI) for cervical spine (C-spine) clearance following blunt trauma. We sought to characterize the utilization of MRI of the C-spine at a Level I trauma center.
Methods: All blunt trauma patients undergoing a computed tomography (CT) of the C-spine between January 2009 and December 2018 were reviewed. The CT and MRI results, demographics, clinical presentation, subspecialty consultations, and interventions were recorded. The MRI results were considered clinically significant if they resulted in cervical thoracic orthosis/halo placement or surgical intervention. Linear regression models were utilized to identify trends.
Results: There were 9,101 patients that underwent a CT of the C-spine, with 513 (5.6%) being positive for an acute injury. MRI was obtained for 375 (4.1%) of patients. A linear increase in the proportion of patients undergoing an MRI was noted, from 0.9% in 2009 to 5.6% in 2018 (p < 0.01). Of the 513 patients with a positive CT, 290 (56.5%) had an MRI. In 40 (13.8%) of them, the CT demonstrated a minor injury. Clinically significant MRI findings were noted only in two (5.0%) of the 40 patients, and both had a neurologic deficit on initial examination. Of the 8,588 patients with a negative CT, 85 (1.0%) underwent an MRI. Of those, 9 (10.6%) had a clinically significant MRI with all but one presenting with a neurological deficit.
Conclusion: MRI is increasingly utilized for C-spine clearance following blunt trauma. MRI was exceedingly unlikely to demonstrate a clinically significant finding in the absence of a neurological deficit, when the CT was negative or included minor injuries. Trauma centers are encouraged to constantly evaluate their own practices and intervene with education and collaboration to limit the excessive use of unnecessary resources.
Level of Evidence: Therapeutic/Care Management Study, Level III or IV. Diagnostic test, level IV.