Cervical Injury: Identifying the Low-Risk Patient

ABSTRACT & COMMENTARY

Source: Hoffman JR, et al. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma. New Engl J Med 2000;343:94-99.

This is a multicenter, prospective, observational trial designed to test a decision rule used to identify patients at low risk for blunt cervical injury in whom radiography can be safely excluded. The decision instrument required patients to satisfy the following criteria in order to be classified as low risk: 1) no midline cervical tenderness; 2) no focal neurologic deficit; 3) normal alertness; 4) no intoxication; and 5) no painful, distracting injuries. The instrument was applied prospectively in a large cohort of blunt trauma patients treated at 21 academic and non-academic centers. Radiographs were obtained at physician discretion. More than 34,000 patients were enrolled, of which 818 (2.4%) had cervical spine injury. The decision rule identified all but eight injuries (sensitivity, 99% [95%, CI 98-99.6%]; negative predictive value, 99.9% [95%, CI 99.8-100%]; specificity, 12.9%; positive predictive value, 1.9%). Only two of these patients had clinically significant fractures, and only one required surgical intervention. Using this decision rule, radiography could have been safely avoided in 12.6% of patients.

Comment by Michael A. Gibbs, MD, FACEP

Missed cervical spine injury can have catastrophic results for both patients and physicians. Early identification of these injuries should be an absolute priority. While a philosophy of liberal radiographic imaging will accomplish this goal, it comes at the expense of a large number of negative radiographs, delays in evaluation, unnecessary exposure to radiation, and staggering cost. Using a decision rule to identify the low-risk patient in whom radiographs can be excluded safely makes good clinical sense. While several prior studies have proposed using this strategy, none have had the statistical power to validate the conclusions. The results of the National Emergency X-ray Utilization Study (NEXUS) represent a milestone of academic accomplishment in emergency medicine. A trial of this size is unlikely to be duplicated, and the proposed decision rule will rapidly become an integral part of our practice. The clinician should keep in mind that several of these criteria are subjective. "A little bit" of cervical tenderness should be considered a positive finding, as should "a couple of beers." "Distracting injury" is perhaps the most subjective of these criteria, and will vary widely from patient to patient. These criteria should be used, but use them with care and attention to detail.