Cervical Spine Imaging in Trauma

Author Credentials

Written by: Steven Lindsey, MD, Emory University Department of Emergency Medicine

Editor: Navdeep Sekhon, MD, Baylor College of Medicine

Update: July 2023

Case Study

A 32 year-old man presents to the Emergency Department after being involved in a motor vehicle accident. He was a restrained driver on a residential street when the car in front of him suddenly stopped, causing him to strike their rear bumper. He denies loss of consciousness, was able to walk immediately after the accident, and is only complaining of neck pain. On exam, his vital signs are reassuring, he is neurologically intact and not intoxicated, and has diffuse but mild midline cervical spine tenderness. Your suspicion for a cervical spine fracture is low, but you wonder if you still have to obtain imaging since he has cervical spine bony tenderness.

Objectives 

By the end of this module, the you will be able to:

  1. Describe the clinical decision rules to determine the indication for cervical spine imaging in the emergency department.
  2. Understand the best imaging modality to evaluate for cervical spine fractures.
  3. Describe the next steps after a cervical spine fracture is discovered on imaging.
  4. Describe indications for further diagnostic imaging of the cervical spine.

Introduction

Neck pain is a common occurrence in the trauma patient, and as Emergency Medicine clinicians, it is our role to identify serious pathologies. One of the most feared causes of neck pain in the trauma patient is an unstable cervical spine injury, which can result in neurologic injury including paralysis if not immobilized and treated appropriately. 

The two main causes of an unstable cervical spine injury are:

  1. Cervical spine fracture
  2. Ligamentous injury

Cervical spine fractures encompass a broad array of injury patterns, creating a spectrum of morbidity from benign yet painful conditions to permanent disability and death. It is estimated that around 1-2% of patients presenting after blunt trauma will have some type of cervical spine fracture, making it of paramount importance in identifying these injuries since failure to recognize a fracture can worsen morbidity and mortality. Ligaments of the cervical spine play an important role in stabilizing the cervical spine, and ligamentous injury can cause an unstable cervical spine. These are difficult to diagnose as X-ray and CT scans are unable to directly detect them.

Initial Actions and Primary Survey

Most patients arriving by ambulance with blunt trauma will have been immobilized with a rigid cervical collar prior to arrival. If a patient arrives without a cervical collar and there is concern for cervical spine injury, a cervical collar should be applied until the primary survey can be completed and a thorough clinical assessment of the cervical spine can be completed. 

During the primary survey, it is important to maintain cervical spine immobilization while focusing on the potential life-threatening conditions that may be present. This is particularly true if a patient needs to be intubated as part of the airway assessment and providers should consider intubating with techniques that minimize movement of the cervical spine (e.g. video laryngoscopy). 

 

For more information on spinal immobilization, please review the following CDEM M3 Curriculum Chapter: Spinal immobilization (saem.org).

While assessing for disability, if a gross motor or sensory deficit is noted, it is particularly concerning for cervical spine fracture or injury and should indicate a need for prompt imaging and a detailed neurologic exam on secondary survey. 

For instances when there may be a delay in imaging or if the prehospital cervical collar is poorly fitting, consider swapping the prehospital cervical collar, which is generally harder and less comfortable for patients, to a more long-term cervical collar, such as an Aspen. Poorly fitting cervical collars are at best uncomfortable for patients, but may also be ineffective at cervical immobilization, can cause skin breakdown, and may even elevate intracranial pressure.

 

Presentation

Patients with cervical spine injuries can manifest with a variety of symptoms, making a thorough evaluation of the cervical spine of paramount importance. Patients will generally present with neck pain and cervical spine tenderness. Focal neurologic deficits, particularly those involving the upper extremities, are very worrisome for cervical spine injury. As with many pathologies, patients at extremes of age can present more atypically, with the elderly presenting with an absence of pain and children presenting with a more limited range of motion. 

It is also important to note that patients who are altered, unresponsive or intoxicated, may not demonstrate the signs or symptoms of a cervical spine injury. Emergency Medicine physicians should have a low threshold to immobilize and work up these patients.

There are few incomplete spinal cord syndromes that warrant further attention:

Types of Incomplete Spinal Cord Injury

Syndrome

Section of Cord Injured

Findings

Central Cord Syndrome

Central portion of spinal cord

Weakness in the upper extremities greater than weakness in the lower extremities. Sacral sensory sparing.

Brown-Sēquard Syndrome

Lateral Spinal cord (hemi-section)

Ipsilateral loss of motor function, proprioception and vibration. Contralateral loss of pain and temperature sensation.

Anterior Cord Syndrome

Anterior ⅔ of spinal cord

Bilateral loss of motor function, pain and temperature below level of injury. Preserved motor function, pain, and temperature sensation

Posterior Cord Syndrome

Posterior ⅓ of spinal cord

Loss of bilateral tough, proprioception and vibration below level of injury. Preserved motor, function, pain and temperature sensations.

Table 1. Types of Incomplete Cord Syndromes.

Diagnostic Testing

Clinical Decision Rules

When evaluating a patient with any traumatic injury, one of two validated, widely used, and accepted clinical decision instruments can be applied to assist in determining which patients require imaging of their cervical spine: the NEXUS (National Emergency X-Radiography Utilization Study) criteria and the Canadian Cervical Spine Rule (CCR). 

While both tools are validated and accepted, it is important to know their test characteristics in considering which to apply to the patient in question. Table 2 shows the data from the landmark studies for NEXUS and CCR.

NEXUS vs Canadian C-spine Rules


Sensitivity

Specificity

NEXUS

99.6%

12.9%

Canadian C-Spine Rules

100%

42.5%

Table 2. Test characteristics of NEXUS and CCR for clinically significant cervical spine injury.

 

Two later studies have found that the sensitivity of NEXUS may be lower, although they included significantly fewer patients (8,000 vs 34,000 for the landmark NEXUS study). 

NEXUS Criteria

The NEXUS criteria was developed to help identify patients who would not benefit from cervical spine imaging in trauma. Some studies suggest that it could reduce imaging in trauma patients by as much as 12.6% 


The NEXUS Criteria follows:  A patient who HAS all of the following components can safely have their cervical spine clinically cleared without imaging:

  • No midline tenderness
  • No distracting injury
  • No neurologic deficit
  • No intoxication
  • No altered mental status

Canadian Cervical Spine Rule

Image 4. Canadian C-spine rules. Please note that dangerous mechanism includes: fall from greater than or equal to 3 feet or 5 stairs, axial load to the head, high speed MVC, motorized recreational vehicle and bicycle collision with an object. This image is courtesy of Teresa Chan, MD and used under the Creative Commons license. Original image located at: Tiny Tip | Tiny Tip | Canadian C-spine Rule Mnemonic - CanadiEM.

A few notes on the CCR:

  • The rule can only be applied to alert (GCS 15) patients. 
  • Dangerous mechanism: fall from > 1 meter/5 stairs, axial load injury (e.g. diving), high speed MVC (>100 km/hr), rollover MVC, MVC with ejection, motorized recreational vehicles, bicycle collisions.
  • Simple rear-end MVC excludes: pushed into oncoming traffic, hit by bus/large truck, hit by high-speed vehicle.

Choosing an Imaging Modality

If the patient fails to have their cervical spine cleared through applying the NEXUS or CCR, they must have their cervical spine radiographically cleared. Table 2 lists the benefits and downsides of the two initial radiographic choices for imaging the cervical spine.

X-Ray vs CT Scan Imaging of the Cervical Spine


Pros

Cons

Cervical spine X-ray

  • Significantly less radiation
  • Potentially lower cost to patient
  • Poor sensitivity (as low as 50-60%)
  • Difficult to obtain adequate views*

Cervical spine CT

  • Excellent sensitivity (98%)
  • More radiation
  • Potentially higher cost to patient
Table 3. Pros and Cons of X-ray versus CT in imaging for cervical spine fractures. 
*Adequate views: AP, odontoid, and lateral (including the C7/T1 interspace).

Given the particularly low sensitivity of X-ray when compared to CT in evaluating the cervical spine and the associated potentially significant consequences of missing an unstable fracture, CT is now the imaging modality of choice for initial imaging of the cervical spine in the trauma patient. When CT is not available or in specific patient populations (e.g. pediatrics), x-ray may be considered, paying particularly close attention to the adequacy of the images.

It is important to note that Xrays and CT scans of the cervical spine are unable to detect ligamentous injury. If there is concern for a ligamentous injury causing an unstable cervical spine despite a negative CT scan, an MRI should be performed. This should be done when patients have persistent neurologic deficits despite negative imaging. 

Treatment

Many different stable and unstable fracture morphologies exist within the cervical spine and are out of the scope of this section. If a cervical fracture is found on imaging, immediate consultation with a spinal surgeon (most commonly Orthopedics or Neurosurgery) is the next step.  Maintain cervical immobilization with a rigid cervical collar until a spinal surgery consultation with recommendations has been completed.

Remember to swap out the prehospital cervical collar for a more comfortable collar, if not already done. Several different brands of these types of cervical collars exist which include the Miami J, Aspen, and Philadelphia collars.

Specific Considerations

After obtaining the initial imaging, there may be additional specific circumstances to consider. They are listed below.


  1. Your patient has a CT that is negative for fractures, but they still have midline cervical tenderness
    • The data are currently limited on this topic, but with modern generation CT scanners, the incidence of clinically-significant cervical spine injury is extremely low in neurologically intact patients. 
    • With this in mind, there is increasing comfort with clearing a cervical collar in patients with a negative CT and an intact neurologic exam.
    • Historically MRI and/or flexion-extension x-rays were used in these patients.
  2. Your patient has a negative CT but is obtunded (e.g. altered, intubated, otherwise unreliable exam)
    • Similarly to patients who are examinable, there is a very low incidence of clinically significant cervical spine injury in obtunded patients.
    • Based on these data, the Eastern Association for the Surgery of Trauma conditionally recommends removal of the cervical collar in obtunded patients after a negative high-quality CT alone.
  3. Your patient has a negative CT but is not neurologically intact
    • CT can miss certain injury patterns, most notably central cord syndrome and significant ligamentous injury.
    • If your patient has persistent neurologic symptoms despite a negative high-quality CT, an MRI of the cervical spine should be obtained.
  4. Your patient has a fracture that involves C1, C2, or C3, and the fracture line goes through the transverse foramen, and/or there is subluxation of the facet joints
    • In these patients, there is increased risk of injury to the vertebral arteries.
    • As a result, CT angiogram of the neck should be obtained to evaluate for blunt vascular injury.

Pearls and Pitfalls

  • Both the NEXUS criteria and the Canadian Cervical Spine Rules have been well validated and adopted in use. If patients pass one of these decision instruments, no cervical spine imaging is needed.
  • Cervical spine CT has supplanted cervical x-rays in the adult population. Cervical spine x-ray may still be the initial imaging in resource-limited settings and scenarios where radiation exposure is a strong consideration (e.g. Pediatrics), but a negative cervical x-ray lacks the sensitivity of detecting many cervical spine fractures.
  • Maintain a cervical collar until CT is complete and negative, at which the cervical collar can be safely removed in obtunded or neurologically-intact awake patients.
  • If a cervical spine fracture is found on imaging, consultation with a spinal surgeon should be obtained, along with transitioning the patient to a still rigid, but more comfortable, cervical collar.

Case Study Resolution

You apply the Canadian C-spine rules to your patient and determine that since he does not have a high-risk feature and does have a low risk feature (ambulatory), you can safely remove the rigid cervical collar. You have your patient range 45 degrees left and right without difficulty, upon which they have passed the Canadian C-spine rules and do not require cervical spine imaging. They are treated with ibuprofen and safely discharged home.

References

  1. Sundstrøm T, Asbjørnsen H, Habiba S, et al. Prehospital use of cervical collars in trauma patients: a critical review. J Neurotrauma. 2014 Mar 15;31(6):531-40. 
  2. Hoffman JR, Mower WR, Wolfson AB, et aI. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma. National Emergency X-Radiography Utilization Study Group. N Engl J Med. 2000 Jul 13;343(2):94-9. 
  3. Stiell IG, Wells GA, Vandemheen KL, et al. The Canadian C-spine rule for radiography in alert and stable trauma patients. JAMA. 2001 Oct 17;286(15):1841-8. 
  4. Stiell IG, Clement CM, McKnight RD, et al. The Canadian C-spine rule versus the NEXUS low-risk criteria in patients with trauma. N Engl J Med. 2003 Dec 25;349(26):2510-8. 
  5. Dickinson G, Stiell IG, Schull M, et al. Retrospective application of the NEXUS low-risk criteria for cervical spine radiography in Canadian emergency departments. Ann Emerg Med. 2004 Apr;43(4):507-14. 
  6. Mower WR, Hoffman J. Comparison of the Canadian C-Spine rule and NEXUS decision instrument in evaluating blunt trauma patients for cervical spine injury. Ann Emerg Med. 2004 Apr;43(4):515-7.
  7. Gonzalez RP, Fried PO, Bukhalo M, et al. Role of clinical examination in screening for blunt cervical spine injury. J Am Coll Surg. 1999 Aug;189(2):152-7. 
  8. Holmes JF, Akkinepalli R. Computed tomography versus plain radiography to screen for cervical spine injury: a meta-analysis. J Trauma. 2005 May;58(5):902-5. 
  9. Patel MB, Humble SS, Cullinane DC, et al. Cervical spine collar clearance in the obtunded adult blunt trauma patient: a systematic review and practice management guideline from the Eastern Association for the Surgery of Trauma. J Trauma Acute Care Surg. 2015 Feb;78(2):430-41. 
  10. Inaba K, Byerly S, Bush LD, et al. Cervical spinal clearance: A prospective Western Trauma Association Multi-institutional Trial. J Trauma Acute Care Surg. 2016 Dec;81(6):1122-1130. 
  11. Lockwood MM, Smith GA, Tanenbaum J, et al. Screening via CT angiogram after traumatic cervical spine fractures: narrowing imaging to improve cost effectiveness. Experience of a Level I trauma center. J Neurosurg Spine. 2016 Mar;24(3):490-5.