Free Canadian c spine rule Calculator | emergencymedicine Clinical Decision Support

How it Works

Assessment Steps

01

1. Any High-Risk Factor? Check for age ≥ 65 years, dangerous mechanism (fall > 3 feet/5 stairs, axial load to head, high-speed MVC > 100 km/h, motorized recreational vehicle, bicycle collision), or paresthesias in extremities. If YES → Radiography indicated.

02

2. Any Low-Risk Factor? Check for simple rear-end MVC, sitting position in ED, ambulatory at any time since injury, delayed onset of neck pain, or absence of midline c-spine tenderness. If NO to all → Radiography indicated.

03

3. Range of Motion? Can the patient actively rotate their neck 45 degrees to the left and right? If NO → Radiography indicated. If YES → Safe to clear C-spine clinically without imaging.

Interpretation Thresholds

Passes all 3 steps	Clinically cleared. Extremely low risk of significant C-spine injury. No imaging required.
Fails any step	Not cleared. Radiography (CT C-spine preferred in adult trauma) is strictly required.

Clinical Pearls

Clinical Pearl

The Canadian C-Spine Rule is highly sensitive (99.4%) for clinically important cervical spine injuries. When applied correctly, a negative result allows the clinician to confidently remove the cervical collar without ordering a CT scan.

Known Limitations

Cannot be applied to patients with a significant distracting injury, intoxication, or altered mental status, as their pain response is unreliable.

The definition of a "dangerous mechanism" can sometimes be subjective in the chaotic triage environment (e.g., estimating the exact speed of a vehicle collision).

Not validated for penetrating neck trauma or patients with known rigid spinal pathology (e.g., ankylosing spondylitis or severe rheumatoid arthritis).

Cannot be safely applied to the pediatric population (use PECARN guidelines instead).

Next Steps

Actionable Clinical Management

01

1. If the patient safely passes the rule: Clinically clear the cervical spine, remove the rigid collar, and discharge the patient if no other injuries warrant admission.

02

2. If the patient fails the rule: Maintain spinal precautions (rigid collar) and order a non-contrast CT of the cervical spine. Plain radiographs are largely obsolete in adult trauma centers.

03

3. If CT is negative but the patient has severe, persistent midline neck pain or neurologic deficits: Keep the collar on and arrange an MRI of the cervical spine to evaluate for ligamentous injury or spinal cord contusion.

04

4. Consult neurosurgery or orthopedic spine surgery immediately if imaging reveals any fracture, subluxation, or ligamentous disruption.

The Evidence

Derivation Study

The Canadian C-spine rule for radiography in alert and stable trauma patients.

Stiell IG et al. • JAMA.. 2001;Vol 286(15): 1841-1848. Derived in a cohort of 8,924 patients. Demonstrated a sensitivity of 100% and specificity of 42.5% for identifying clinically important cervical spine injuries.

Origins & History

Development Context

Developed by Dr. Ian Stiell and the multicenter Canadian CT Head and C-Spine Study Group in 2001. The objective was to safely reduce the immense volume of negative cervical spine radiographs ordered in North American emergency departments. It was designed to improve upon the earlier NEXUS criteria by offering higher sensitivity and reducing the ambiguity of "distracting injuries."

Canadian C-Spine Rule

When to Use

When to Use

Patient Population

How it Works

Assessment Steps

Interpretation Thresholds

Clinical Pearls

Clinical Pearl

Known Limitations

Next Steps

Actionable Clinical Management

The Evidence

Derivation Study

The Canadian C-spine rule for radiography in alert and stable trauma patients.

Origins & History

Development Context

In Recent Clinical News

Canadian C-Spine Rule

When to Use

When to Use

Patient Population

How it Works

Assessment Steps

Interpretation Thresholds

Clinical Pearls

Clinical Pearl

Known Limitations

Next Steps

Actionable Clinical Management

The Evidence

Derivation Study

The Canadian C-spine rule for radiography in alert and stable trauma patients.

Origins & History

Development Context

In Recent Clinical News