Hey, everybody. This is Steve Carroll for E.M. Basic Essential Evidence. Today, we'll be talking

about the study behind the famous nexus criteria. This criteria helps us avoid unnecessary C-spine

imaging in certain patients, and allows us to clinically clear a patient in cervical collar.

As always, this podcast doesn't represent the views or opinions of the Department of Defense,

the U.S. Army, or the Ford Hood Post Command.

So the title of this article is validity of a set of clinical criteria to rule out injury

to the cervical spine in patients with blunt trauma.

It was published in New England Journal of Medicine, July 13, 2000, and the first author

is Jerry Hoffman. So the background.

So this is a study that defined the nexus clinical decision rule that helps us determine

whether or not a patient needs imaging of their C-spine after blunt trauma. There are five criteria.

I remember them with the mnemonic A, B, C, D, E, A is for alter mental status, B is for bony, midline tenderness,

C is for CMS dysfunction or neurodeficit, D is for drugs or alcohol, and E stands for elsewhere,

meaning a distracting injury somewhere else besides the spine. So talk about this study design a little

bit. So this was a

prospective multi-center observational study. This means that the authors defined a rule ahead of time,

defined a data collection method ahead of time, then applied it to patients at 21 different hospitals.

They needed 21 hospitals to participate because C-spine fractures and injuries are rare, so you need

a large number of patients to capture those few that have fractures. When you're validating a clinical

rule, you need to make sure that you have enough patients who actually have the disease that you're

looking for. Otherwise, your results aren't valid. As a little bit of historical context,

there's nothing magical about these criteria, but they represent a standard set of common-sense

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