Canadian C-Spine Rule

Christian Vaillancourt, MD and his colleagues recently published an article in the journal Annals of Emergency Medicine (2009;54:663-671) entitled "The Out-of-Hospital Validation of the Canadian C-Spine Rule by Paramedics." This rule was originally developed for "clinical clearance" (e.g., without the use of x-rays) of persons with possible cervical spine fracture (broken neck) in alert and stable trauma patients by qualified persons (generally, emergency physicians) in a health care setting (such as an emergency department). This particular study found that paramedics can apply the Canadian C-Spine Rule reliably, without missing important cervical spine injuries.

The Rule, properly applied to an awake and alert injured person for which there is a concern for a cervical spine injury, provides the following direction:

1. If a person has a high-risk factor (age greater than or equal to 65 years; a dangerous mechanism of injury [a fall from an elevation greater than or equal to 3 feet; fall down 5 or more stairs; direct blow to top of head, such as a diving board accident; motor vehicle accident characterized by high speed, rollover or passenger ejection; motorized recreational vehicle accident; bicycle collision]; or numbness/tingling in an arm or leg), then neck immobilization and x-rays are indicated.

2. If the victim is not able to actively rotate his or her neck, under their own power and without assistance, 45 degrees to the left and right without causing pain, then neck immobilization and x-rays are indicated. If the victim is completely without pain at rest and on active range of motion of the neck, then it is unlikely that an unstable fracture is present.

3. Low-risk accident factors that allow safe assessment of range of motion of the neck include simple rear-end motor vehicle collision (excludes being pushed into oncoming traffic, being hit by a bus or large truck, rollover, or hit at high speed by a vehicle); person is capable of a sitting position; person is ambulatory (e.g., walking); delayed onset of neck pain; and absence of posterior or anterior pain on examining (e.g., pressing upon) the neck. If the accident is deemed to be low-risk, then the victim is asked to attempt rotation of his or her neck under their own power and without assistance. See number 2 above.

What does this mean for the layperson who is practicing medicine in the outdoors? It provides a very reasonable approach to deciding who might be safely examined and when to apply a cervical spine immobilization technique. The overall goal is to not move someone's neck if he or she might have an unstable fracture, where movement could jeopardize the integrity of the spinal cord. Clinical judgment and intuition serve important roles, because it truly is best to always err on the side of "better safe than sorry." However, if the victim is low risk from all perspectives, it allows the rescuers more comfort in moving the victim or allowing self-extrication from a difficult situation or hostile environment.