My Approach to Clearing C-Spines

I gave a talk the other day on clearing C-Spines, with Prezi linked here. As a disclaimer, this is my approach based on my clinical experience and from reading the literature – you should discuss this amongst your colleagues and review the literature to see if you reach the same conclusions.  I would appreciate some comments – peer review if you will.

Objectives of the Talk:

1. Apply the Canadian C-Spine Rule and NEXUS criteria to aid in the use of clearing C-spines in Adults
2. Gain an approach to clearing C-Spines in Pediatric Patients
3. Understand when further imaging with CT and MRI may be indicated

Introduction:

• Canadian ER physicians see 200, 000 alert, stable trauma victims per year
  • Of these, 1% will end up having a clinically important C-Spine injury [CSI]
  • If you consider just patients going for neck X-Rays, 2.5% will have a CSI [from NEXUS]
  • A large variation in clearing c-spine practice continues to exist
  • Although there is literature to guide our approach – much of it is confusing and contradictory
  • Persistent medico-legal fear continues to influence our practice.
  • 2 validated rules exist that can help identify the need for radiography and clear C-Spines safely.

Clinical decision rules [CDRs]:

CDRs usually include a mix of history, physical findings and tests.

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Advantages of using CDRs

• CDRs are useful where diagnostic uncertainty.
• CDRs allow physicians to provide a standardized approach to problems.
• CDRs allow physicians to make efficient and bias-free clinical decisions [bg_faq_end]

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Challenges with CDRs

• Applicability to the patient you are seeing [e.g. CCR – excluded pediatric patients]
• Designed by academics and applied by mostly non-academics
• Fail if doc cannot remember nuances of inclusion/exclusions
• Publish best case sensitivity [need to look at the confidence intervals] [bg_faq_end]

PEARL: You do not have to memorize CDR’s – know where to look. I sometimes show/discuss them with patients so that they understand my thinking process. In the following cases we will apply the two major CDRs to guide our decision making.

 

CASE 1:

65 year-old F driver rear-end collision on highway at 100 kmh

• Did NOT lose consciousness.
• Was wearing her seat-belt & the airbags deployed.
• Walks into the ER.
• Is complaining of left wrist, left ankle and chest wall tenderness.

On examination:

• Alert, oriented. No complaints of neck pain or neurologic deficits.
• Moving her neck to show you that she is okay.
• Mild seat-belt abrasion to chest.
• Abrasion to her wrist and ankle.

What would your approach be? What about the next case?[bg_faq_end]

CASE 2:

12 year-old passenger seated in the back seat of a vehicle that was hit by another car while changing lanes. The car was spun around and then hit a light pole. The patient did not lose consciousness. He was wearing his seat belt.

• The patient has been brought to the ER in a C-Spine collar.
• He is complaining of mild headache from a bruise to his right temple.

On Examination:

• Alert oriented.
• In a C-spine Collar.
• No complaints of neck pain or neurologic deficits.
• Small bruise to Right temple.

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NEXUS Rule¹

Prospective observational study in 34000 patients in 21 centres in USA

• Results:
  • 818 patients had C-Spine fractures on x-ray
  • Rule missed 8/818. BUT only 2/818 were clinically significant
  • Sensitivity = 99.6% (98.6‐100%,95%CI)
• Commentary:
  • Largest study that we have.
  • Subsequent validation by Steill et al 93% sensitive
  • Useful in children [see below]
  • Useful in those that fail CCR by criteria [age and mechanism] [bg_faq_end]

Bottom Line

Patients have virtually ZERO risk of CSI if they have:

• NO Mid-line tenderness
• NO Altered mentation
• NO intoxication [alcohol or drugs]
• NO neurologic deficits
• NO distracting injury
  • Long bone fracture
  • Large: crush/degloving/burn/laceration
  • ER docs opinion

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For more information on distracting injuries

• Most recently Rose et al 2012² showed that only 1/464 [0.2%] of patients with no neck pain and a distracting injury had a c-spine injury on CT scan
• Another study³ shows that 95% of CSI patients with distracting injuries WILL STILL HAVE NECK PAIN despite the “distracting injury”
• Good Summary can be found at: ALIEM blog [bg_faq_end]

Spine Injuries in children

• Children < 3 years of age will not comply with 3-view radiographs
  • Fortunately injuries below C1-C3 level are almost non-existent [until 6 years of age]
  • AP and Lateral radiographs + “clinical assessment” is the standard of care
  • High Risk: BIG mechanism, multiply injured, head injury.

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Applying CDR in Children

• NEXUS and kids⁴
  • 3,065 patients under 18
    • 88 under 2 years
    • 817 aged 2-8 years [Big cohort compared to Paeds Studies]
    • 2,160 aged 8-17 yrs [Big Cohort]

• 30 kids had CSI
  • Almost all were in older kids [aged 11-17]
  • ZERO CHILDREN WERE MISSED BY APPLYING NEXUS RULE

• Only 5/3065 kids with fractures were 9 and under
  • only 2 kids <3 had CSI [type 3 odontoid in a 2yo and Occipital fracture in a 3yo]
  • the 3 kids 6-9 yo had significant fractures that I  think would not have been missed [cranio-cervical dissociation, C1 ant/post arch fracture + type 2 odontoid, C4 flexion teardrop fracture]
  • As of my lit review – one case report of NEXUS miss, a 3yo who had a lap-belt sign [visceral (and therefore distracting) injury]

• Although the authors do not recommend NEXUS application in the <8yo cohort, I feel that the number of kids 5-8 together with the reliability of a child >5yo means that it may be applicable.
• My practice. I use it in the reliable > 5yo. I have low threshold for “distracting injury”. I consider High risk as: high risk mechanism & child has other injuries.
• For kids that I cannot use the rule [e.g. toddlers and infants]:
  • ALL get immobilised with sandbags/tape/collar
  • ALL get bedside AP and Lateral Xray
  • If xrays look fine: COLLAR OFF
    • If child moves neck: CLEAR
    • If child has guarding/torticollis: CT Neck [bg_faq_end]

CASE 3:

40 yo Male who [drunk] fell down a flight of stairs.

• He was knocked out briefly.
• He is not complaining of any C –Spine tenderness.

On Examination:

• Alert oriented [but drunk].
• In a C-spine Collar.
• No complaints of neck pain or neurologic deficits.
• Small bruise to Right temple.

This patient fails NEXUS due to intoxication. What do you do with this guy?

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The Canadian C Spine Rule [CCR]⁵:

• Prospective study 8900 patients in 10 Canadian centres
  • Included:
    • GCS 15 and normal VS
    • neck pain from injury or
    • no neck pain and trauma above clavicles, worrisome mechanism for C spine, not ambulatory
• Excluded < 16yo, presenting >48h, pregnant, unstable,  GCS <15, known spine dis [e.g. RA], trivial injury [laceration]
• Defined CSI : any #, dislocation or ligamentous instability
• Secondary outcome: clinically unimportant injury
• 2700 patients did not get X-rays [14 day follow up phone call]
• Results:
  • Sensitivity = 100% [98‐100]
  • Specificity = 42% [40-44]

How to Apply the Rule:  You have to ask yourself 3 questions?

1) Is there a high risk feature that mandates radiography? … if NOT …

2) Is there ANY low risk feature that will allow safe range-of-motion testing? If yes …

3) Can the patient move 45 deg left and right? If yes – CLEAR! [bg_faq_end]

Here’s a visual representation of the CCR:

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Common Problems with the CCR

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What to do with midline tenderness?

What some of the literature shows:

• No midline tenderness confers NPV of 98%
• CCR applied as is shows that presence of ANY low risk feature allows for safe ROM
• CCR did not exclude drunks. Only requisite is GCS 15.

• [Duane et al J Trauma 2011⁶] [Sicker patients 6.4% incidence of CSI]
  • Midline tender + sober + no distracting injury = 12% will have injury on CT scan
  • Midline tender + either intoxicated or with distracting injury = 8.4% injury on CT scan
  • NO comment on whether these injuries are clinically significant or not. [bg_faq_end]

The bottom line:

Midline tenderness does not trump any of the other “Low Risk Features” that allow safe range-of-motion testing. If persistent and significant this suggest enough risk to X-ray (and maybe CT depending on patient).

What to do with drunk patients?

• Risk for C-Spine injury + GCS < 15 = Plain Radiographs.
• Wait for them to have GCS 15 and try and clear clinically.
• If they can’t comply with plain films go straight to CT.

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Perception that CT is better for ALL?

• CT Is NOT Better for ALL

I have heard from a couple of colleagues that “plain films miss 20-30% of C-Spine injuries”. I even attended a recent conference where a speaker [who I respect] suggested a “CT for all” approach for those we cannot clear with NEXUS and CCR because:

1. It appears that there’s an epidemic of inadequate X-Rays of the C spine
2. It appears that ER docs all of a sudden seem to suck at reading one of their bread and butter tests.

I took a look the “CT is better literature” and I do not agree:

1. The incidence of CSI in these studies is 5-23%. [Compare that to 2.4% for NEXUS]
2. They seem to include the sicker crowd that would not typically be able to be cleared clinically [unconscious, altered]
3. They compare inadequate C-Spine Films to adequate CT scans!
4. They have methodologic flaws or are making these recommendations based on weak evidence [bg_faq_end]

The bottom line:

[1] Alert stable patients at risk of C-Spine injury with an incidence of about 2.5%
–> PLAIN FILMS ARE JUST FINE HERE

[2] Sicker patients with an incidence of greater than 5% [head injured, altered, polytrauma etc]

–> THESE PATIENTS MAY NEED CT

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When CT may be necessary:

Reasonable indications for CT from my experience:

• Suspicious looking X-Ray/inadequate X-Ray
• Persistent significant midline tenderness
• Polytrauma cases going for CT head since co-incidence of head/neck injuries 5%
• Intubated patients / patients unable to comply with 3 views + swimmers’ view
• Patients with existing C spine disease / elderly patients at risk for false positive X-Ray[bg_faq_end]

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When MRI may be necessary:

CT alone has been shown to be a reliable way to exclude unstable injuries; however studies like this from the CJEM⁷ are contradictory and incite fear in clinicians. Some of the challenges arise because:

• Evidence suggests that 2% of patients with negative CT may have a neurosurgical lesion on an MRI
• Surgeons do not have uniform practice in these patients
• Often CT is negative but you have a symptomatic patient
• Despite the utility of the Flex-Ex View in the CJEM article above, neck pain/symptoms despite Normal CT has a differential diagnosis – the most important of which may or may not be picked up on Flex-Ex!

Bottom line – MRI indicated for:

Negative CT and persistent significant pain/guarding or Neurologic deficit.[bg_faq_end]

 

I would welcome your thoughts.

This post was originally published on the ERMentor Blog. It was revised by Riley Golby and Rob Carey and reposted on CanadiEM on XX XX XXXX.

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References

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