Background and Rationale
The cervical spine is the upper part of the spine between the head and shoulders (the neck). The incidence of traumatic cervical spine injury (CSI) in children is very low. However it is very important not to miss this type of injury. To detect CSI, several types of scan imaging techniques can be used (computed tomography (CT) scan, magnetic resonance imaging (MRI) and plain radiography (x-ray)). CT scan and x-ray use radiation that can lead to an increased risk in the development of cancer, especially in children. We therefore need to use plain radiography or CT scan in children only if really necessary. To avoid unnecessary use of those radiographic imaging techniques, it is important to look for clinical tests that can detect whether children are at risk for cervical spine injury and if radiographic imaging needs to be done.
The NEXUS criteria and Canadian C-spine Rules are tools that doctors use to decide whether adults are at risk for cervical spine injury and whether they need to use radiographic imaging. These tools are already being used in children, but little information is known about how accurate they are in children. The goal of this review was therefore to evaluate whether these tools can also be used safely and effectively in children.
We searched medical literature databases to identify studies which tested how well both decision tools can establish whether children are at risk for CSI after blunt trauma. We performed the search in February 2015.
Quality of the evidence
We identified three studies of moderate to good quality. All studies tested the accuracy of the NEXUS criteria, and one of them also tested the accuracy of the Canadian C-spine Rules.
Since only one study looked at the accuracy of the Canadian C-spine Rules, there is not enough evidence at the moment to determine whether the Canadian C-spine Rules can be used safely in children. The sensitivity and specificity of the NEXUS criteria varied among the three studies, meaning that there is a chance of false-negative test results when using the NEXUS criteria, and as a result there is a chance of missing cervical spine injury if doctors only rely on the NEXUS criteria. We therefore consider that the NEXUS criteria are at best a guide to clinical assessment, with current evidence not supporting strict or protocolized adoption of the tool into pediatric trauma care. The conclusion of our review is that we need more research to evaluate the accuracy of the NEXUS criteria and the Canadian C-spine rules for routine use in children.
There are currently few studies assessing the diagnostic test accuracy of the NEXUS criteria and CCR in children. At the moment, there is not enough evidence to determine the accuracy of the Canadian C-spine Rule to detect CSI in pediatric trauma patients following blunt trauma. The confidence interval of the sensitivity of the NEXUS criteria between the individual studies showed a wide range, with a lower limit varying from 0.18 to 0.91 with a total of four false negative test results, meaning that if physicians use the NEXUS criteria in children, there is a chance of missing CSI. Since missing CSI could have severe consequences with the risk of significant morbidity, we consider that the NEXUS criteria are at best a guide to clinical assessment, with current evidence not supporting strict or protocolized adoption of the tool into pediatric trauma care. Moreover, we have to keep in mind that the sensitivity differs among several studies, and individual confidence intervals of these studies show a wide range. Our main conclusion is therefore that additional well-designed studies with large sample sizes are required to better evaluate the accuracy of the NEXUS criteria or the Canadian C-spine Rule, or both, in order to determine whether they are appropriate triage tools for the clearance of the cervical spine in children following blunt trauma.
Pediatric cervical spine injury (CSI) after blunt trauma is rare. Nonetheless, missing these injuries can have severe consequences. To prevent the overuse of radiographic imaging, two clinical decision tools have been developed: The National Emergency X-Radiography Utilization Study (NEXUS) criteria and the Canadian C-spine Rule (CCR). Both tools are proven to be accurate in deciding whether or not diagnostic imaging is needed in adults presenting for blunt trauma screening at the emergency department. However, little information is known about the accuracy of these triage tools in a pediatric population.
To determine the diagnostic accuracy of the NEXUS criteria and the Canadian C-spine Rule in a pediatric population evaluated for CSI following blunt trauma.
We searched the following databases to 24 February 2015: CENTRAL, MEDLINE, MEDLINE Non-Indexed and In-Process Citations, PubMed, Embase, Science Citation Index, ProQuest Dissertations & Theses Database, OpenGrey, ClinicalTrials.gov, World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Health Technology Assessment, and the Aggressive Research Intelligence Facility.
We included all retrospective and prospective studies involving children following blunt trauma that evaluated the accuracy of the NEXUS criteria, the Canadian C-spine Rule, or both. Plain radiography, computed tomography (CT) or magnetic resonance imaging (MRI) of the cervical spine, and follow-up were considered as adequate reference standards.
Two review authors independently assessed the quality of included studies using the QUADAS-2 checklists. They extracted data on study design, patient characteristics, inclusion and exclusion criteria, clinical parameters, target condition, reference standard, and the diagnostic two-by-two table. We calculated and plotted sensitivity, specificity and negative predictive value in ROC space, and constructed forest plots for visual examination of variation in test accuracy.
Three cohort studies were eligible for analysis, including 3380 patients ; 96 children were diagnosed with CSI. One study evaluated the accuracy of the Canadian C-spine Rule and the NEXUS criteria, and two studies evaluated the accuracy of the NEXUS criteria. The studies were of moderate quality. Due to the small number of included studies and the diverse outcomes of those studies, we could not describe a pooled estimate for the diagnostic test accuracy. The sensitivity of the NEXUS criteria of the individual studies was 0.57 (95% confidence interval (CI) 0.18 to 0.90), 0.98 (95% CI 0.91 to 1.00) and 1.00 (95% CI 0.88 to 1.00). The specificity of the NEXUS criteria was 0.35 (95% CI 0.25 to 0.45), 0.54 (95% CI 0.45 to 0.62) and 0.2 (95% CI 0.18 to 0.21). For the Canadian C-spine Rule the sensitivity was 0.86 (95% CI 0.42 to 1.00) and specificity was 0.15 (95% CI 0.08 to 0.23). Since the quantity of the data was small we were not able to investigate heterogeneity.