ACEP: Clinical decision rules can reduce spine injury imaging
The use of two clinical decision rules should help emergency department (ED) physicians reduce the number of patients who should be imaged due to possible cervical spine injuries (CSI), said Linda A. Regan, MD, in a presentation at the 2009 American College of Emegency Physicians' (ACEP) meeting last week in Boston.

Regan, assistant professor of emergency medicine at Johns Hopkins Medical Institutions in Baltimore, said the National Emergency X-Radiography Utilization Study (NEXUS) was the first clinical decision rule applied to CSI. That study (Hoffman et al, New England Journal of Medicine 2000; 343: 94-99) enrolled 34,019 patients with blunt trauma who underwent radiography. 

It found 818 radiographically documented CSI on three-view cervical spine radiographs. Eight patients screened negative and were found to have CSI. Of these eight patients, only two had “clinically significant” injury. The injuries were those that were isolated, required no treatment and, if missed, would not have resulted in any harm.

The NEXUS researchers determined that imaging could have been deferred in 4,309 patients (12.6 percent of those in the study). The study’s criteria for a low probability of CSI are:
  • No midline tenderness;
  • No focal neurologic deficit;
  • Normal alertness;
  • No intoxication (left up to clinician to clinically decide); and
  • No painful distracting injury (left up to clinician to decide).

She also reviewed the Canadian C-Spine Rule for Radiography in Alert and Stable Trauma Patients (Stiell et al, Journal of the American Medical Association 2001: 286; 1841-1848). This study enrolled 8,924 stable patients with blunt trauma. It excluded pregnant patients, children under 16 with CSI or anyone with unstable vitals.

About 69 percent underwent imaging, and researchers found 151 radiographically documented cases of CSI. No patients with clinically important injuries were missed. An additional 28 patients were found to have clinically unimportant injuries. The injuries were those that did not require stabilization or specialized follow up and, according to the authors, the C-Spine Rule found 27 of these 28 patients.

The C-Spine Rule holds that only patients with the following high risk factors involved in their injuries should be radiographed:
  • Over the age of 65;
  • Fall from greater than 1 meter;
  • Injury from a vehicle rollover or ejection; and
  • Bicycle collision.

In addition, if a patient presents with any of the following, they should be radiographed:
  • Inability to sit up in the ED;
  • Unable to be ambulatory at any time;
  • Delayed onset of neck pain;
  • Midline tenderness; and
  • Inability to actively rotate neck.

The use of this rule could have brought the rate of imaging from 68.9 percent to 58.2 percent of the patients in that study, according to the authors.

As for which of the rule sets ED physicians should use, Regan said they "need to see what they are comfortable with."