Not all trauma patients need to be imaged, said Swaminatha Mahadevan, MD, Stanford University School of Medicine in California in an educational session Tuesday at ACEP14.

He talked emergency physicians through a pair of evidence-based algorithms for omitting cervical spine imaging in adults: NEXUS and the Canadian Cervical Spine Rule. If the algorithm indicates that the patient should be imaged, then Dr. Mahadevan recommends use of computed tomography (CT), especially for moderate- to high-risk patients due to the greater sensitivity of CT compared to X-rays. A normal CT clears the patient of a bone injury, but still leaves open the possibility of a ligamentous injury. Thus, the question then becomes how best to clear the patient who is awake, alert, has a normal motor examination and CT scan, but has neck pain.

MRI or flexion extension X-rays can clear patients of ligamentous injury. MRI’s are excellent for imaging spinal cord and soft-tissues, but might be overly sensitive. Flexion extension X-rays are not particularly useful because they are often inadequate at imaging ligaments. New research suggests, however, that it may be acceptable to forgo a second image and discharge an alert patient with a negative CT.

Dr. Mahadevan presented the results of a prospective, observational study on cervical spine clearance published in 2014 in JAMA Surgery. The study took place from January 2010 to May 2011 in a level 1 trauma center. It included 830 adults who required a CT of the cervical spine. Patients received a newer generation (64 slice), high-resolution, multi-detector CT with sagittal and coronal reconstruction. One hundred patients also received an MRI. Approximately half (46) of the MRIs revealed new findings, but none of the findings were clinically relevant. The investigators concluded that CT for detection of clinically significant injury had a sensitivity of 100% and a specificity of 100%. Cervical spine CT also had a negative predictive value of 100%. Dr. Mahadevan communicated the take-home message as, “basically, you can just take the collar off and be done.”

Dr. Mahadevan acknowledged two caveats, however, to the conclusion. The first is that none of the patients in the study had advanced cervical spondylosis. A 2011 study found that cervical spondylosis was a risk factor for clinically significant injury on MRI. So, patients with advanced cervical spondylosis may need to be given an MRI. The second caveat is that none of the patients were obtunded.

“If your patient is unconscious, leave the collar on and just admit them,” he said.

Lara C. Pullen is a freelance medical writer in Chicago.