Context High levels of variation and inefficiency exist in current clinical
practice regarding use of cervical spine (C-spine) radiography in alert an
d stable trauma patients.
Objective To derive a clinical decision rule that is highly sensitive for d
etecting acute C-spine injury and will allow emergency department (ED) phys
icians to be more selective in use of radiography in alert and stable traum
a patients.
Design Prospective cohort study conducted from October 1996 to April 1999,
in which physicians evaluated patients for 20 standardized clinical finding
s prior to radiography. In some cases, a second physician performed indepen
dent interobserver assessments.
Setting Ten EDs in large Canadian community and university hospitals. Patie
nts Convenience sample of 8924 adults (mean age, 37 years) who presented to
the ED with blunt trauma to the head/neck, stable vital signs, and a Glasg
ow Coma Scale score of 15.
Main Outcome Measure Clinically important C-spine injury, evaluated by plai
n radiography, computed tomography, and a structured follow-up telephone in
terview. The clinical decision rule was derived using the kappa coefficient
, logistic regression analysis, and chi (2) recursive partitioning techniqu
es.
Results Among the study sample, 151 (1.7%) had important C-spine injury. Th
e resultant model and final Canadian C-Spine Rule comprises 3 main question
s: (1) is there any high-risk factor present that mandates radiography (ie,
age greater than or equal to 65 years, dangerous mechanism, or paresthesia
s in extremities)? (2) is there any low-risk factor present that allows saf
e assessment of range of motion (ie, simple rear-end motor vehicle collisio
n, sitting position in ED, ambulatory at any time since injury, delayed ons
et of neck pain, or absence of midline C-spine tenderness)? and (3) is the
patient able to actively rotate neck 45 degrees to the left and right? By c
ross-validation, this rule had 100% sensitivity (95% confidence interval [C
I], 98%-100%) and 42.5% specificity (95% CI, 40%-44%) for identifying 151 c
linically important C-spine injuries. The potential radiography ordering ra
te would be 58.2%.
Conclusion We have derived the Canadian C-Spine Rule, a highly sensitive de
cision rule for use of C-spine radiography in alert and stable trauma patie
nts. If prospectively validated in other cohorts, this rule has the potenti
al to significantly reduce practice variation and inefficiency in ED use of
C-spine radiography.