National Emergency X-Radiography Utilization Study (NEXUS)

Original Editor - Trista Chan

Top Contributors - Trista Chan  

Objective[edit | edit source]

The National Emergency X-Radiography Utilization Study (NEXUS) was developed in 1998 and is recommended in many international guidelines as a triage tool in emergency settings[1]. It aims to provide healthcare professionals with a standardized and evidence-based approach for assessing whether cervical spine imaging is necessary for trauma patients[2]. The NEXUS is specifically designed to identify patients at low risk for a cervical spine injury, hence to avoid unnecessary radiation exposure, mental stress and healthcare expenses[2].

Intended Population[edit | edit source]

The NEXUS tool targets patients who have suffered from traumatic injuries that may affect the cervical spine, such as those involved in accidents, falls, or other traumatic events who present with neck pain, tenderness, or neurological symptoms. However, it is not recommended to be used in paediatric or geriatric populations, due to additional predisposing risk factors that differ from adult populations, and insufficient evidence to conclude the accuracy of using the tool on these populations [3]

Method of Use[2][edit | edit source]

The low-risk criteria in the National Emergency X-Radiography Utilization Study (NEXUS) include:

  • Absence of tenderness at the posterior midline of the cervical spine.
  • Absence of signs of intoxication.
  • Scoring of 15 on the Glasgow Coma Scale, indicating normal alertness level.
  • Absence of neurological abnormalities.
  • Absence of injury leading to significant pain or distraction.

If a patient does not meet all of the above criteria, they are referred for imaging.

Evidence[edit | edit source]

The initial study on the NEXUS criteria indicated a high sensitivity of 99.6% with a confidence interval of 0.95. This shows that it was very effective in identifying patients who needed imaging [3]. Several studies also assessed the NEXUS rule and found a high sensitivity ranging from 0.83 to 1.0, but with a lower specificity of 0.13 to 0.46[2]. It also reported a negative likelihood ratio of 0.081, showing that the NEXUS is useful in ruling out the need for further imaging[2].

However, the original research only included a limited number of paediatric subjects, leading to a questionable applicability of the tool on children[4]. Subsequent studies investigated the potential of applying NEXUS criteria to the paediatric populations and found its sensitivity ranging from 0.57 to 1.0 and specificity ranging from 0.2 to 0.54[3][4]. Additionally, the studies reported a wide range in confidence interval (0.18-0.91), which indicates the possibility of false negative results when NEXUS criteria are applied to this population[3][4].

Similarly, some studies found a variable result of the NEXUS criteria in older patients, with sensitivity ranging from 0.66 to 1.0, raising concerns about the applicability of the tool in this population as well[5].

References[edit | edit source]

  1. Vazirizadeh-Mahabadi M, Yarahmadi M. Canadian C-spine Rule versus NEXUS in Screening of Clinically Important Traumatic Cervical Spine Injuries; a systematic review and meta-analysis. Archives of academic emergency medicine [Internet]. 2023;11(1):e5.
  2. 2.0 2.1 2.2 2.3 2.4 Michaleff ZA, Maher CG, Verhagen AP, Rebbeck T, Lin CW . C. Accuracy of the Canadian C-spine rule and NEXUS to screen for clinically important cervical spine injury in patients following blunt trauma: a systematic review. Canadian Medical Association Journal [Internet]. 2012 Oct 9;184(16):E867–76.
  3. 3.0 3.1 3.2 3.3 Ekhator C, Nwankwo I, Nicol A. Implementation of National Emergency X-Radiography Utilization Study (NEXUS) Criteria in Pediatrics: A Systematic Review. Cureus. 2022 Oct 8; ‌
  4. 4.0 4.1 4.2 4. Slaar A, Fockens MM, Wang J, Maas M, Wilson DJ, Goslings JC, et al. Triage tools for detecting cervical spine injury in pediatric trauma patients. Cochrane Database of Systematic Reviews [Internet]. 2017 Dec 7 [cited 2020 Apr 10];
  5. Paykin G, O’Reilly G, Ackland H, Mitra B. Review article: NEXUS criteria to rule out cervical spine injury among older patients: A systematic review. Emergency Medicine Australasia. 2017 Dec 12;30(4):450–5. ‌