Retrospective application of the NEXUS low-risk criteria for cervical spine radiography in Canadian emergency departments

Ann Emerg Med. 2004 Apr;43(4):507-14. doi: 10.1016/j.annemergmed.2003.10.036.


Study objective: We evaluate the accuracy, reliability, and potential impact of the National Emergency X-Radiography Utilization Study (NEXUS) low-risk criteria for cervical spine radiography, when applied in Canadian emergency departments (EDs).

Methods: The Canadian C-Spine Rule derivation study was a prospective cohort study conducted in 10 Canadian EDs that recruited alert and stable adult trauma patients. Physicians completed a 20-item data form for each patient and performed interobserver assessments when feasible. The prospective assessments included the 5 individual NEXUS criteria but not an explicit interpretation of the overall need for radiography according to the criteria. Patients underwent plain radiography, flexion-extension views, and computed tomography at the discretion of the treating physician. Patients who did not have radiography were followed up with a structured outcome assessment by telephone to determine clinically important cervical spine injury, a previously validated outcome measurement. Analyses included sensitivity and specificity with 95% confidence interval (CI), kappa coefficient, and potential radiography rates.

Results: Among 8,924 patients, 151 (1.7%) patients had an important cervical spine injury. The combined NEXUS criteria identified important cervical spine injury with a sensitivity of 92.7% (95% CI 87% to 96%) and a specificity of 37.8% (95% CI 37% to 39%). Application of the NEXUS criteria would have potentially reduced cervical spine radiography rates by 6.1% from the actual rate of 68.9% to 62.8%. Of 11 patients with important injuries not identified, 2 were treated with internal fixation and 3 with a halo.

Conclusion: This retrospective validation found the NEXUS low-risk criteria to be less sensitive than previously reported. The NEXUS low-risk criteria should be further explicitly and prospectively evaluated for accuracy and reliability before widespread clinical use outside of the United States.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Canada
  • Cervical Vertebrae / diagnostic imaging*
  • Cervical Vertebrae / injuries*
  • Emergency Service, Hospital
  • Female
  • Humans
  • Male
  • Middle Aged
  • Radiography
  • Retrospective Studies
  • Sensitivity and Specificity
  • Spinal Cord Injuries / diagnostic imaging*
  • Spinal Injuries / diagnostic imaging
  • Wounds, Nonpenetrating / diagnostic imaging