Table 4. The Canadian C-Spine rule for the need for radiological imaging.

Adapted from [8].

The Canadian C-Spine rule
Any high-risk factor? Age at least 65 years or dangerous mechanisms (including falls from at least 1 meter or 5 stairs, axial load to head such as diving, high-speed collision, rollover, ejection from vehicle bicycle collision, motorized recreational vehicles) or paraesthesia in extremities	If yes to any, then needs radiological investigation
Any low-risk factor that allows safe assessment of the range of motion? Simple rear-end motor vehicle collision (excluding rollover,  hit by a high-speed vehicle, hit by a large vehicle, pushed into oncoming traffic) or sitting position in an emergency department or ambulatory at any time or delayed onset of neck pain or absence of midline C-spine tenderness	If no to any, then needs radiological investigation
Able to actively rotate neck?	If unable to rotate neck, then needs radiological investigation
If there is no high-risk factor, there is a low-risk factor that allows safe assessment of range of motion and the patient can actively rotate the neck, then there is no need for radiological investigation.