Loading...
Printed on 6/29/2026
For informational purposes only. This is not medical advice.
The National Emergency X-Radiography Utilization Study (NEXUS) criteria identify trauma patients who can have their c-spine cleared clinically without imaging. All 5 criteria must be absent to safely forego imaging, with 99.6% sensitivity for clinically significant cervical spine injuries. Score altered alertness objectively with [Glasgow Coma Scale](/tools/glasgow-coma-scale). For concurrent head injury evaluation, apply [Canadian CT Head Rule](/tools/canadian-head-ct). In polytrauma, assess overall physiologic severity with [Revised Trauma Score](/tools/revised-trauma-score) and [Shock Index](/tools/shock-index).
Formula: All 5 criteria absent → c-spine can be cleared. Any criterion present → imaging recommended.
Save your results with a free account
Keep a history of calculations, favorite tools, and access your dashboard anytime.
Systematically evaluate each of the 5 NEXUS criteria: (1) no posterior midline cervical spine tenderness; (2) no evidence of intoxication (alcohol, drugs, or any substance impairing assessment); (3) normal level of alertness (GCS 15, oriented × 4, no acute intracranial injury); (4) no focal neurological deficit (new sensory or motor deficit in any extremity); (5) no painful distracting injury (any injury that may distract the patient from localizing cervical pain).
If ALL 5 criteria are absent (negative), the c-spine is low risk and imaging is NOT required — 99.6% sensitivity for clinically significant injury. If ANY single criterion is present (positive), imaging IS required. The rule is binary — even one positive criterion mandates imaging. For midline tenderness specifically, palpate each spinous process from occiput to T1.
If imaging is required, most modern trauma centers use CT cervical spine (not plain films) due to superior sensitivity for fractures (~98% vs ~52% for plain films in high-risk patients). MRI is indicated if neurological deficits are present (to assess spinal cord, disc herniation, ligamentous injury). Plain X-rays may be used in low-mechanism, low-risk patients in resource-limited settings.
Emergency physicians, trauma surgeons
NEXUS is used in the ED to determine whether a cervical spine collar can be removed and imaging deferred in alert, cooperative blunt trauma patients. All 5 criteria must be absent to safely forego imaging. Used in over 34,000 patients in the original validation study.
Emergency physicians, radiologists
Cervical spine imaging in trauma patients who meet NEXUS low-risk criteria is unnecessary and avoidable. Applying NEXUS systematically reduces unnecessary radiation exposure, CT scanner utilization, and healthcare costs without compromising detection of clinically significant injuries.
Sports medicine physicians, athletic trainers
On the sports sideline, NEXUS provides a structured approach to cervical spine evaluation after contact injuries. All 5 criteria must be met before removing protective equipment and mobilizing the athlete. Any criterion failed = spinal precautions and emergency transport.
Trauma teams
Trauma activations include systematic NEXUS assessment after initial primary survey resuscitation. Documentation of all 5 criteria allows formal c-spine clearance in eligible patients, freeing the patient from collar and facilitating nursing care, airway management, and comfort.
Paramedics, EMTs
Advanced prehospital protocols in some systems use NEXUS criteria to guide selective cervical spine immobilization — applying collars only when criteria suggest injury risk. Selective immobilization reduces unnecessary immobilization burden, transport time, and complications without increasing missed injury rates in well-trained EMS providers.
The original NEXUS study missed 8 of 818 clinically significant c-spine injuries (false negative rate ~1%). None of the missed injuries required surgical intervention. While the false negative rate is low, any missed c-spine injury carries significant medicolegal risk. Apply NEXUS systematically and document findings carefully.
Midline cervical tenderness means tenderness directly over the posterior spinous processes — from the occiput down through C7. Paraspinal muscle tenderness (beside the midline) is NOT a positive criterion. Palpate each spinous process individually, applying firm pressure with a single finger from occiput to T1.
Direct comparison (Stiell et al., JAMA 2003) showed CCR sensitivity 99.4% vs NEXUS 95.3%, specificity 45.1% vs 36.8%. CCR is more complex (age criteria, mechanism categories, safe active rotation) but reduces imaging by ~40% vs NEXUS. Use whichever tool your institution has formally implemented — NEXUS is more widely used in the US.
Distracting injury is not precisely defined — it means any injury that might prevent the patient from fully focusing on cervical pain (long bone fractures, large lacerations, significant soft tissue injury, visceral pain, burns). If you are uncertain whether the injury is distracting, err toward imaging. Femur fractures, multiple rib fractures, and large extremity injuries typically qualify.
NEXUS was derived exclusively in blunt trauma patients. Penetrating neck trauma — gunshot wounds, stab wounds — has different patterns of c-spine injury and different clinical presentations. CT angiography and CT c-spine are typically obtained for all penetrating neck trauma regardless of neurological exam.
Plain cervical spine X-rays miss 50–90% of fractures visible on CT, particularly occipital-C1-C2 junction injuries. Modern trauma centers have largely moved to direct CT c-spine for patients meeting imaging criteria. Plain films may still be used in low-mechanism patients at community facilities. MRI is essential when neurological deficits are present.
Elderly patients have unique c-spine injury patterns (odontoid fractures from low-energy falls, posterior element fractures, DISH calcification causing stiff spines prone to fracture). NEXUS was validated across all ages but performs less well in the elderly. Many trauma surgeons have a lower imaging threshold for elderly patients with any neck pain after trauma, even if NEXUS criteria are met.
Children under 8 years have higher proportion of upper c-spine injuries (occiput–C2) and higher rates of SCIWORA (spinal cord injury without radiographic abnormality) due to ligamentous laxity and relatively large head. NEXUS applies to pediatric patients but sensitivity may be lower. Any concerning mechanism in a young child with neck pain warrants low-threshold imaging.
NEXUS published by Hoffman et al. (NEJM 2000) from 34069 blunt trauma patients. Sensitivity 99.6% for clinically significant c-spine injury, specificity 12.9%. Canadian C-Spine Rule (Stiell et al., NEJM 2003): sensitivity 99.4%, specificity 45.1%. Head-to-head comparison by Stiell et al. (JAMA 2003): CCR had higher sensitivity and specificity. Both tools endorsed by ACEP and Eastern Association for the Surgery of Trauma (EAST 2009 guidelines).
The NEXUS rule provides a binary outcome: the cervical spine can be cleared clinically, or imaging is required. If all five criteria are absent (no posterior midline cervical tenderness, no focal neurological deficit, normal alertness, no intoxication, and no painful distracting injury), the c-spine can be cleared without imaging. The probability of a clinically significant cervical spine injury in this scenario is extremely low (negative predictive value of 99.8% in the original study of over 34,000 patients).
If any single criterion is present, the c-spine cannot be cleared clinically and imaging is recommended. The choice of imaging modality (plain radiographs vs. CT) depends on clinical context and institutional protocols, though CT has largely replaced plain films in most trauma centers due to superior sensitivity for fractures. The presence of multiple positive criteria increases the pre-test probability of injury but does not change the binary recommendation.
Use the NEXUS criteria for any trauma patient in the emergency department when you need to determine whether cervical spine imaging is necessary. The rule is applicable across all ages and mechanisms of injury, making it more broadly applicable than the Canadian C-Spine Rule (which has specific age and mechanism restrictions). It is particularly useful in busy emergency departments where rapid clinical clearance of the c-spine can expedite patient flow.
The NEXUS criteria should be applied during the secondary survey after life-threatening injuries have been addressed. The rule is most valuable when the clinician is considering whether imaging can be safely avoided. In patients with obvious high-energy mechanisms or clinical instability, imaging is typically obtained regardless of the rule. The rule's simplicity (five yes/no criteria) makes it easy to remember and apply without a calculator.
The NEXUS criteria have several recognized limitations. The definition of 'distracting injury' is subjective and not precisely defined in the original study, leading to inconsistent application among clinicians. What constitutes a distracting injury remains a matter of clinical judgment. The 'altered alertness' criterion is also somewhat vague and may be interpreted differently by different providers.
The NEXUS study had a 99.6% sensitivity, meaning it missed 8 of 818 injuries in the original cohort. While none of the missed injuries required surgical intervention, any missed cervical spine injury is a significant medicolegal concern. The Canadian C-Spine Rule has demonstrated slightly better sensitivity and specificity in comparative studies. Additionally, NEXUS was validated primarily in the era of plain radiographs, and its performance characteristics may differ in the current era of CT as the primary imaging modality. The rule does not perform as well in elderly patients (age over 65), where the Canadian C-Spine Rule may be preferred.
For related assessments, see Canadian Head CT and Glasgow Coma Scale.
Disclaimer: This tool is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about your health.
April 21, 2026 · trust-baseline
Clinical trust metadata enabled for this tool page with structured review/version fields.
Apply the Canadian CT Head Rule to determine if CT is needed after minor head injury (GCS 13–15). Achieves 98.4% sensitivity for neurosurgically significant injuries, safely reducing CT use.
OpenEmergencyCalculate the Glasgow Coma Scale score to assess level of consciousness. Used worldwide in emergency medicine and trauma assessment.
Open