Emergency Medicine
NEXUS C-Spine Criteria
Whether cervical-spine imaging can be avoided.
Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.
Background
The NEXUS (National Emergency X-Radiography Utilization Study) criteria are a clinical decision rule used in blunt trauma to identify patients who do not require cervical-spine imaging. It comprises five criteria: midline cervical tenderness, focal neurological deficit, altered level of alertness, intoxication, and a distracting painful injury. If all five are absent, the cervical spine can be considered clinically clear and imaging can be safely avoided. The rule was designed to reduce unnecessary radiography while maintaining a very high sensitivity for significant injury.
Interpreting the result
A patient who is negative on all five criteria is at very low risk of clinically important cervical-spine injury, and imaging is not required. The presence of any one criterion means the rule cannot exclude injury, so imaging is indicated and immobilisation should be maintained. The rule is intended to be highly sensitive, accepting some over-imaging in exchange for rarely missing injury. It applies to blunt trauma and should be applied with care in children and older adults.
Worked example
An alert, sober adult after a low-speed road collision has no midline cervical tenderness, no neurological deficit, no distracting injury and a normal level of alertness — all five NEXUS criteria are absent. The cervical spine can be cleared clinically and cervical-spine imaging is not required.
Pearls / pitfalls
- All five criteria must be absent to clear the spine — any single positive criterion mandates imaging and continued immobilisation.
- “Distracting injury” is a matter of clinical judgement; a painful injury that could mask neck pain counts.
- Apply with extra caution at the extremes of age — performance is less certain in young children and frail older patients (where the Canadian C-Spine Rule excludes age ≥65).
- A negative rule clears the patient clinically but does not override ongoing clinical concern — reassess if symptoms evolve.
Evidence & validation
Validated by Hoffman and colleagues in a large prospective study published in 2000, NEXUS demonstrated very high sensitivity for clinically significant cervical-spine injury. It is endorsed within emergency-medicine practice; the Canadian C-Spine Rule is an alternative tool with comparable aims.
Frequently asked questions
When can cervical-spine imaging be avoided using NEXUS?
When all five NEXUS criteria are absent — no midline tenderness, no focal neurological deficit, normal alertness, no intoxication and no distracting injury. In that case the cervical spine can be cleared clinically without imaging.
What counts as a distracting injury?
Any painful injury that could distract the patient from neck pain, such as a long-bone fracture or a large laceration. It is a clinical judgement, and if in doubt the criterion should be considered present.
Can NEXUS be used in children and the elderly?
It should be applied cautiously at the extremes of age, where evidence is less robust. In older patients in particular, many clinicians prefer the Canadian C-Spine Rule or a lower threshold for imaging.
How does NEXUS differ from the Canadian C-Spine Rule?
Both aim to safely reduce imaging in blunt trauma. The Canadian C-Spine Rule incorporates age, mechanism and the ability to rotate the neck, and excludes patients aged 65 or over, whereas NEXUS uses the five clinical criteria. They are complementary tools.
References
- Hoffman JR, Mower WR, Wolfson AB, et al. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma (NEXUS). N Engl J Med. 2000;343(2):94–99.
- NICE NG39: Major trauma: assessment and initial management. 2016.
About the creator
Hoffman JR et al.
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