NEXUS — C-Spine Low-Risk Criteria
All 5 criteria must be ABSENT to clear C-spine without imaging. Check all that are PRESENT.
What is NEXUS C-Spine Criteria?
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Imagine you are helping a friend clean their gutters, and they take a tumble off the ladder. Or maybe you get rear-ended at a stoplight on your morning commute. Your neck feels a bit stiff, and you head to the emergency room to get checked out. One of the first things the medical team has to decide is whether you need an X-ray or a CT scan of your neck (the cervical spine, or 'C-spine' for short). While scans are amazing tools, they also mean exposure to radiation, long wait times in a busy hospital, and hefty medical bills. This is where the NEXUS criteria come to the rescue. NEXUS is a super-smart, five-point checklist that doctors and paramedics use to figure out if you can safely skip those neck scans after a bump, slip, or fall. Developed from a massive landmark study of over 34,000 patients, it acts as a medical safety net. The checklist asks five simple questions about how you feel and what happened during your accident. If you pass all five tests, it means your risk of a serious neck injury is incredibly low—so low that you can bypass the imaging machine entirely, skip the radiation, and head home to rest. How does this help you in your daily life? It takes the anxiety and guesswork out of emergency situations. Knowing how medical professionals evaluate neck pain helps you advocate for yourself and your family. It gives you peace of mind, helping you understand why a doctor might confidently say, 'You are good to go without a scan!' or, conversely, why they are insisting on an immediate X-ray. It is all about keeping you safe while saving you from unnecessary, expensive, and time-consuming medical procedures.
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Formula
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NEXUS Checklist Score = Number of danger signs present (0 to 5). You can safely skip neck imaging only if your score is 0. This means you must answer 'No' to all 5 danger signs: (1) No pain along the middle of your neck, (2) No signs of being drunk or high, (3) Fully awake and alert, (4) No numbness, tingling, or weakness in your arms or legs, and (5) No other major, painful injuries distracting you. If you check 'Yes' to even one, you need a scan.Variable Legend
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| Symbol | Name | Unit | Description |
|---|---|---|---|
| GCS | Glasgow Coma Scale | 3–15 | Alertness criterion threshold: must be 15 for NEXUS low-risk classification |
| NEXUS_score | NEXUS positive criteria count | 0–5 | Number of positive criteria; any score >0 mandates imaging; score = 0 allows clinical clearance |
| BAL | Blood alcohol level | mg/dL (or mmol/L) | Quantitative intoxication measure; elevation above legal limit supports NEXUS intoxication criterion |
| Sn | Sensitivity | % | NEXUS sensitivity for significant C-spine injury: 99.6% in original study |
| Sp | Specificity | % | NEXUS specificity: 12.9% — reflects frequent imaging in low-risk group due to rule design |
How to NEXUS C-Spine Criteria
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- 1Feel the midline: The doctor gently presses down the very center of the back of your neck, from the base of your skull to the top of your upper back. If you feel pain directly on those bony bumps, that is a positive sign for tenderness.
- 2Check for intoxication: The medical team looks for signs of alcohol or drug use. If someone is slurring their words, unsteady on their feet, or has had too much to drink, they cannot reliably say where it hurts, which triggers a scan.
- 3Test alertness: You need to be fully awake and clear-headed. The team will ask simple questions like 'Where are you?' and 'What month is it?' to make sure there is no confusion or head injury clouding your judgment.
- 4Look for nerve issues: The doctor will check if you have any numbness, 'pins and needles' tingling, or sudden weakness in your hands, arms, or legs. Any nerve trouble means we need a closer look via imaging.
- 5Identify distracting injuries: If you have a broken leg or a deep, painful cut somewhere else, your brain might focus entirely on that pain and ignore a neck injury. If you have another severe injury, it counts as a 'distractor,' and you will need a scan.
- 6The Green Light: If you have absolutely none of these five issues, your neck can be cleared on the spot without any scans.
- 7The Caution Flag: If even one of these five signs is present, the medical team will order a scan (usually a CT scan) to be absolutely sure your spine is safe.
Worked Examples
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All five safety conditions are met perfectly. This patient can skip the radiation and the scanner.
Because the patient is clear-headed, sober, has no nerve issues, no other distracting injuries, and absolutely no tenderness directly on the spine bones, the risk of a spinal injury is virtually zero. They can go home to rest without needing a scan.
Even if the neck doesn't hurt when pressed, alcohol makes the patient's feedback unreliable.
Because alcohol numbs pain and impairs judgment, we cannot trust a 'painless' neck assessment. To keep this patient safe, the medical team must order a scan to verify the neck is okay.
A broken wrist is so painful it can easily mask a neck injury.
The human brain can only process so much pain at once. The excruciating pain from the broken wrist could easily drown out a serious neck injury. Because of this 'distracting injury,' a neck scan is mandatory to be absolutely safe.
Tingling in both hands after a neck injury is a major red flag for nerve or spinal cord compression.
This patient has two major warning signs: direct pain on the spine bones and tingling in the fingers (a nerve issue). They need urgent imaging, likely both a CT scan and an MRI, to make sure there is no bone fracture or pressure on the spinal cord.
Real-World Applications
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ER nurses use it to quickly sort patients arriving after a car crash, helping to decide who needs to stay in a neck collar and who can stretch comfortably while waiting., where accurate nexus c spine analysis through the Nexus C Spine supports evidence-based decision-making and quantitative rigor in professional workflows
Paramedics use it at the scene of a slip or fall to decide if they need to strap a patient onto a rigid backboard, saving many people from an incredibly uncomfortable ride to the hospital., where accurate nexus c spine analysis through the Nexus C Spine supports evidence-based decision-making and quantitative rigor in professional workflows
Ski patrol teams on the mountain use these basic rules to evaluate fallen skiers and snowboarders before transporting them down the slopes., where accurate nexus c spine analysis through the Nexus C Spine supports evidence-based decision-making and quantitative rigor in professional workflows
Sports trainers on the sidelines of football or rugby games use it as a first-line safety check when a player takes a hard hit to the upper body., where accurate nexus c spine analysis through the Nexus C Spine supports evidence-based decision-making and quantitative rigor in professional workflows
Telehealth doctors use the checklist to advise worried patients who called in after a minor household fall, helping them decide if they need an urgent ER trip or just an ice pack., where accurate nexus c spine analysis through the Nexus C Spine supports evidence-based decision-making and quantitative rigor in professional workflows
Special Cases
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Knocked Out or Unconscious Patients
If an accident was severe enough to knock someone out, or if they are on a breathing machine, the NEXUS checklist cannot be used. Because they cannot talk to us, tell us where it hurts, or squeeze our hands to test their strength, they must automatically receive a CT scan of their neck to rule out any hidden injuries.
Our Grandparents and Older Adults
As we get older, our bones naturally become more fragile due to things like osteoporosis. Even a minor fall from a standing height can cause a neck fracture in an older adult. Because of this, doctors have a much lower threshold for ordering scans for patients over 65, even if they seem to pass the NEXUS checklist.
Motorcyclists and Bicycle Helmets
If you are involved in a motorcycle or bicycle crash, paramedics will keep your neck completely still using a neck collar. To properly check your neck, the helmet has to be carefully removed using a special two-person technique so your neck doesn't move. Because bike crashes involve high speeds, these patients almost always end up getting a scan for safety.
NEXUS C-Spine Reference Quick Guide
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| Safety Test | What the Doctor Checks | What Trigger a Scan? |
|---|---|---|
| 1. Middle Neck Pain | Gently pressing the bony ridge down the center of the neck | Any pain or soreness directly on the bones |
| 2. Intoxication | Signs of alcohol or drug use that might dull pain or cause confusion | Being tipsy, slurring words, or being visibly under the influence |
| 3. Alertness Level | Asking simple questions to ensure you are fully awake and clear-headed | Any confusion, memory loss, or drowsiness from a head bump |
| 4. Nerve Function | Checking for normal strength and feeling in your arms and legs | Numbness, tingling, or weakness in your hands, arms, or legs |
| 5. Distracting Injury | Looking for other painful injuries that might mask neck pain | A broken bone, severe burn, or any other highly painful injury |
| ALL 5 ARE CLEAR | You pass every single safety check with zero issues | No scans needed! Safe to go home and rest |
Frequently Asked Questions
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Can I use this checklist at home to decide if a friend needs to go to the hospital?
No, this checklist is designed strictly for trained medical professionals like doctors, nurses, and paramedics. Assessing things like spinal bone tenderness and nerve function requires clinical training. If you or a friend have had a fall or crash and are experiencing neck pain, always seek professional medical evaluation immediately.
What exactly counts as a 'distracting injury' in everyday terms?
A distracting injury is any injury painful enough to distract you from noticing a neck injury. Common examples include a broken arm or leg, a deep cut that needs stitches, a severe burn, or a crushed finger. If you are hurting badly somewhere else, your brain might tune out the pain in your neck, which is why a scan is required in these cases.
Why does having a beer or two mean I automatically need a neck scan?
Alcohol and drugs dull your body's natural pain signals and can make you less aware of your injuries. Even if you only feel slightly tipsy, your ability to give an accurate, reliable description of your pain is compromised. Because doctor safety guidelines require absolute certainty, any level of intoxication triggers a scan just to be safe.
Is the NEXUS checklist safe to use on my kids if they fall off the monkey bars?
While the NEXUS criteria are highly reliable for adults and older kids, doctors use extra caution with very young children under the age of eight. Young kids often have trouble describing exactly where it hurts or might get scared during an exam, making the checklist harder to apply. For toddlers and young children, pediatricians often rely on specialized kid-friendly guidelines.
Why did the doctor order a CT scan instead of a simple X-ray for my neck?
CT scans are much more detailed than traditional X-rays when it comes to looking at the bones of your neck. An X-ray can sometimes miss small, subtle cracks in the vertebrae, whereas a CT scan provides a 3D view that lets doctors see every tiny detail. In most modern emergency rooms, a CT scan is the gold standard for checking the neck after a trauma.
What is the difference between this and the Canadian C-Spine Rule?
Both are excellent tools used to decide if you need a neck scan, but they go about it slightly differently. The Canadian C-Spine Rule is a bit more detailed, asking about the mechanism of the accident (like whether you fell down stairs or rolled a car) and your age. It is slightly better at reducing unnecessary scans in fully alert patients, while NEXUS is simpler and quicker to use in fast-paced emergency settings.
If my neck only hurts on the sides, can I still be cleared without a scan?
Yes, potentially! The NEXUS criteria specifically look for pain directly along the 'midline'—which is the bony ridge running right down the center of the back of your neck. Pain on the sides of your neck is usually just sore, strained muscles (like whiplash), which is much less dangerous than a bone fracture. If the bones themselves don't hurt and you pass the other four tests, you are likely safe from needing a scan.
Common Mistakes to Avoid
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- !Using the checklist for puncture wounds: NEXUS is only designed for 'blunt trauma' (like falls, car crashes, or sports bumps). It does not work for penetrating injuries like knife or gunshot wounds, which always need immediate imaging.
- !Ignoring a broken arm because the neck feels fine: This is a classic mistake. A screamingly painful broken arm is a major distractor. Even if the patient says their neck feels 100% fine, that broken arm means they fail the checklist and must get a neck scan.
- !Confusing muscle strain with bone pain: Muscle soreness on the sides of the neck is common after a fender bender. Some doctors mistake this for midline tenderness. True midline tenderness is pain directly on the hard spine bones, not the soft muscles next to them.
Pro Tip
Think of the checklist as your 'Safety First' shield. If you have even a single doubt about any of the five steps—especially if someone seems a bit dazed or has another painful injury—don't guess. Always err on the side of getting the scan.
Did you know?
Before this checklist was published in 2000, almost every single person who went to the ER with neck pain got an X-ray! Thanks to this massive study of over 34,000 patients, millions of people have been spared unnecessary radiation and saved millions of dollars in hospital bills!
References
- ›Hoffman JR et al. — NEXUS Low-Risk Criteria (NEJM 2000)
- ›Stiell IG et al. — CCR vs NEXUS direct comparison (CMAJ 2003)
- ›EAST Practice Management Guidelines — Cervical Spine Clearance in the Traumatically Injured Patient
- ›NICE NG41 — Major Trauma Head and Neck Imaging (2016)
- ›Bailitz J et al. — NEXUS Validation Study Design and Outcomes
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