To exclude a cervical fracture in a patient with a neck injury – the patient population to whom it is applied – alert, not intoxicated, no distracting injury (ie. Long bone fracture or large lacerations), clinically a fracture can be excluded if 1) the patient is not high risk – age less than 65 yrs, no history of paresthesiae in extremities, no dangerous injury mechanisms like fall or heavy impact, And 2) patient has low-risk factors that allow a range of motions to be safely assessed like rear-end collision, seated position at the medical consultation, post-trauma ambulation,  delayed onset neck pain, absence of midline cervical spine tenderness And 3) the patient is able to actively rotate the neck 45* to either side