Author: Andrew Tabner, Graham Johnson / Codes: RP4, SLO4, SLO5 / Published: 21/05/2021


Andrew Tabner

Graham Johnson

Paper Title

Projected paediatric cervical spine imaging rates with application of NEXUS, Canadian C-spine and PECARN clinical decision rules in a prospective Australian cohort

Paper Authors

Natalie Phillips ‍, Katie Rasmussen, Sally McGuire, Kerrie-Ann

Abel, Jason Acworth, Geoffrey Askin, Robyn Brady, Mark Walsh,

Franz E Babl ‍

What is already known on this subject

  • In adults, well-evidenced clinical decision rules (CDRs) such as NEXUS rule and Canadian C-Spine rule (CCR) rule can be used to guide the decision to image or not image for possible cervical spine injury (CSI).
  • In children, the validity of CDRs mainly derived in adults is limited and a paediatric risk tool for CSI from the Pediatric Emergency Care Applied Research Network (PECARN) is only in development.
  • The performance of these tools in children, including their potential impact on imaging rates, has not been adequately studied.

What this study adds

  • In a single-centre prospective cohort study of 973 children aged under 16 years with possible CSI, radiographically confirmed CSIs were rare (0.5%).
  • Use of NEXUS, CCR and PECARN tool to guide the decision to image or not image could increase the baseline imaging rate of 41% to between 44% and 68%.

Study Design

A single-centre prospective observational study on all aged under 16 years presenting for assessment of possible CSI to a tertiary paediatric emergency department over a year, commencing September 2015.

What was assessed?

CDR variables from the National Emergency X-Radiography Utilization Study (NEXUS) rule, Canadian C-Spine rule (CCR) and proposed Paediatric Emergency Care Applied Research Network (PECARN) rule were collected prospectively and applied post hoc.


1010 children were enrolled; 973 had not received prior imaging. Of these, 40.7% received cervical spine imaging; 32.4% X-rays, 13.4% CT scan and 3% MRI. All three CDRs identified the five children (0.5%) with CSI who had not received prior imaging. If CDRs were strictly applied as a rule for imaging, projected imaging rates in our setting would be as follows: NEXUS-44% (95% CI 41% to 47.4%), CCR-at least 48.4% (95% CI 45.3% to 51.7%) and PECARN-68% (95% CI 65.1% to 71.1%).

Authors’ Conclusion

CSIs were rare (0.5% of our cohort), however, 40% of children received imaging. CDRs have been designed to guide imaging decisions; if strictly applied as a rule for imaging, the CDRs assessed in this study would increase imaging rates. Projected rates differ considerably depending on the CDR applied. These findings highlight the need for a validated paediatric-specific cervical spine imaging CDR.

Our Take Home

Clinical gestalt appears to perform better than any of the Clinical Decision Rules. To develop a clinical decision rule will require a very large, international study that ultimately may not be of a clinical utility given 1. the rarity of cervical spine injuries in children 2. The presence of a cervical spine injury is usually associated with clinical features or mechanistic/history factors that do not require a Clinical Decision Rule. 

RCEM Curriculum Coverage


Online Learning

Cervical Spine Injury