Canadian C-Spine Rules for Clearing Cervical Spine Without Imaging
The Canadian C-Spine Rule (CCR) allows clinicians to safely clear the cervical spine without imaging in alert and stable trauma patients by following a specific three-step algorithm that has demonstrated 100% sensitivity for detecting clinically important cervical spine injuries. 1
The Canadian C-Spine Rule Algorithm
Step 1: Assess for High-Risk Factors
If ANY of these factors are present, cervical spine radiography is mandatory:
- Age ≥65 years 2, 1
- Dangerous mechanism of injury (fall from ≥3 feet/5 stairs, axial load to head, high-speed motor vehicle collision, rollover, ejection, bicycle collision) 2, 1
- Paresthesias in extremities 2, 1
Step 2: Assess for Low-Risk Factors
If NO high-risk factors are present, assess for low-risk factors that allow safe assessment of range of motion:
- Simple rear-end motor vehicle collision 2, 1
- Patient is sitting in the emergency department 2, 1
- Patient was ambulatory at any time since injury 2, 1
- Delayed onset of neck pain 2, 1
- Absence of midline cervical spine tenderness 2, 1
Step 3: Assess Ability to Actively Rotate Neck
If at least one low-risk factor is present AND the patient can actively rotate their neck 45 degrees to both left and right, the cervical spine can be safely cleared without imaging. 2, 1
Comparison with NEXUS Criteria
The NEXUS (National Emergency X-Radiography Utilization Study) criteria is an alternative approach that requires no imaging if ALL of the following are absent:
- Midline cervical tenderness 2
- Focal neurologic deficit 2
- Altered level of consciousness (GCS <15) 2
- Intoxication 2
- Distracting injury 2
Effectiveness and Safety
- The Canadian C-Spine Rule has demonstrated 100% sensitivity and 42.5% specificity for identifying clinically important cervical spine injuries. 1
- Implementation of the CCR could reduce cervical spine radiography by approximately 58% without missing significant injuries. 1, 3
- The CCR has been successfully implemented by paramedics and emergency department triage nurses with 100% sensitivity for detecting cervical spine injuries. 4, 5
- The CCR has superior sensitivity and specificity compared to the NEXUS criteria. 6
Special Considerations
- For obtunded trauma patients who cannot be clinically evaluated, imaging is required. CT scan of the cervical spine is the preferred initial imaging modality. 2
- Patients with neurological deficits referable to the spine require urgent MRI evaluation. 2
- In unconscious polytrauma victims, management should be based on whether they are expected to be clinically evaluable within 48-72 hours. 2
- Patients with high-risk mechanisms should be immobilized until proper clinical assessment can be performed. 2
Common Pitfalls and Caveats
- Failure to recognize that the CCR cannot be applied to patients who are not alert (GCS <15) or stable. 2, 1
- Misinterpreting the rule by not checking all three components in sequence. 4
- Not recognizing that patients with paresthesias require imaging regardless of other factors. 2, 1
- Attempting to clear the cervical spine in patients with distracting injuries or intoxication, which may mask symptoms. 2
- Not ensuring adequate visualization of the cervicothoracic junction when imaging is performed. 2
By correctly applying the Canadian C-Spine Rule, clinicians can safely reduce unnecessary imaging while ensuring that all clinically significant cervical spine injuries are identified and appropriately managed. 1, 3