To Follow the clinical Decision Rules or to CT the C-Spine
By Dr. Shahd Rowaihy & Dr. Kholoud Babkair
In the usually busy shift, a young gentleman, who was driving at a speed of 100km/h, with no seat built, presented to the ED. There was no rollover or ejection. He didn’t hit his head or chest. The patient was conscious and oriented and denied amnesia.
The Patient arrived with a C-Collar in place and full spinal board immobilization. Initial examination showed a normal primary survey, log roll and E-F.A.S.T. Moreover, the patient was in severe pain that was not localized to any specific area. He wasn’t intoxicated and there were no obvious injuries noted.
The Attending Physician was conflicted weather to proceed with a C-Spine C.T. Scan or to follow one of the C-spine clinical decision rules. This dilemma was brought about because of the high speed/mechanism of the incident.
This article will be discussing the utilization of the N.E.X.U.S. and Canadian C-Spine rule versus C.T. Scan in trauma patients.
Usually after almost any major trauma; chest, pelvis, cervical spine images and E-F.A.S.T. are the standard primary evaluation. Nevertheless, in selected cases, cervical spine imaging could be delayed until the clinical decision rules are applied.
There are two main criteria to be followed. The N.E.X.U.S. criteria, which allow clearance of the cervical spine without imaging if all of the following five points are applicable: (1) no posterior midline tenderness, (2) no focal neurologic deficit, (3) no altered mental status, (4) no intoxication, or (5) no distracting injury 
Another rule that could be used is the Canadian C-Spine Rule (C.C.R.); C.C.R. is composed of the following three questions:
1. Are there any high-risk factors that mandate radiography?
2. Are there any low-risk factors that allow safe assessment of
range of motion?
3. Is the patient able to actively rotate his or her neck 45
degrees to the left and right?
High-risk factors include age older than 65 years, a “dangerous mechanism of injury” (a fall from a height >1 m, an axial loading injury, high-speed MVC [>100 km/hr], rollover, ejection, motorized recreational vehicle or bicycle collision), or the presence of parenthesis. Low-risk factors include simple rear-end vehicle crashes*, sitting position in the emergency department, ambulatory at any time, delayed onset of neck pain, and the absence of midline neck tenderness .
Both the N.E.X.U.S. and the C.C.R. studies recommend obtaining cervical spine radiographs only for patients in whom spinal injury is clinically suspected. Both studies excluded patients with penetrating trauma and those who had sustained direct blows to the neck. Still, both rules have been well validated and are highly sensitive , . The Nexus criteria have a sensitivity of 99.6% and the CCR has a sensitivity of 99.4% . The use of either rule has been shown to significantly limit the number of unnecessary radiographs while missing only rare patients with clinically significant injuries. The false negative value of NEXUS criteria ranges from 0-1.0% and the false negative of CCR ranges from 0-0.11% 
At the same time, in a patient with concerning mechanism of injury or physical findings, computed tomography (CT) scanning is more efficient and effective than plain radiography 
Once the patient has been stabilized, the clinical examination can direct whether additional radiographic examinations are necessary. If a C.T. is performed, reformatted sagittal and coronal images will be more sensitive than axial images alone 
C.T. scanning permits examination without moving the patient from the supine position and is thusly preferable in terms of fracture stabilization, airway control and other life-support measures . C.T. also has the added advantage of fracture detection especially in identifying bony fragments, acute disk herniations, foreign bodies, para-spinal hematomas, and/or extra-medullary hematomas.
Practice guidelines from the Eastern Association for the Surgery of Trauma (E.A.S.T.) recommend that C.T. (from the occiput to T1) to be used as the primary screening method in blunt cervical trauma patients 
Many studies have been done to guide physicians weather to use the clinical criteria or to image the patients instantly, which exaggerated the conflict in this matter.
A study done by Goode T et al, who did a prospective study which was published in February 2014, stated that we are supposed as Emergency Physicians, “to CT all of the blunt trauma patients regardless if they follow the clinical criteria (NEXUS) or not”  and according to Denver D et al, the NEXUS rule is not valid to be used in patients older than 65 years and CT is recommended in this age group  Pekmezci et al, as well, recommended neck CT to trauma patients to prevent missed injuries 
On the other hand; Benayoun et al, published his work in March 2016, did a retrospective cross sectional study and supported using the clinical rules to reduce the patient’s exposure to radiation . Another study done by Rosati Sf et al, in Richmond, Virginia in a combined (adult and pediatrics) trauma center. It was to clear pediatrics patients who are 15 years of age and under, and this study ended with the fact that patients who are clearable by NEXUS criteria decreased the use of CT scans by 23% . While Griffith B et al, stated that strict application of Nexus criteria could potentially reduce the number of screening cervical spine CT’s in trauma; this change would avoid a considerable amount of unnecessary radiation 
Several studies mentioned that the risk of having thyroid cancer in the neck is related to thyroid dosing of the radiation exposure and is mainly influenced by the patient’s age and sex. While other studies suggested that routine use of cervical CT in high-risk injuries has benefits that outweigh the harm , 
Finally, the risk of acquiring malignancy after repeated doses of radiation is well documented in the literature. Combining both rules while trying to make a decision is always a good idea that will end up with even lower false negative rates of missed serious c-spine injuries than each one alone.
Despite that, each rule has its limitation. Thus, they should be applied wisely.
*Simple rear end MVC excludes: pushed into oncoming traffic, hit by a bus or large truck, rollover or hit by high-speed vehicle
1. Hoffman JR, Mower WR, Wolfson AB, Todd KH, Zucker MI: Validity
of a set of clinical criteria to rule out injury to the cervical spine in
patients with blunt trauma. N Engl J Med 2000; 343:94.
2. Stiell IG, et al: The Canadian C-spine Rule for radiography in alert and
stable trauma patients. JAMA 2011; 286:1841.
3. Zoe A. Michaleff, Chung-Wei Christine Lin. “Accuracy Of The Canadian C-Spine Rule And NEXUS To Screen For Clinically Important Cervical Spine Injury In Patients Following Blunt Trauma: A Systematic Review". CMAJ : Canadian Medical Association Journal 184.16 (2012): E867. Web.
4. Bailitz J, et al: CT should replace three-view radiographs as the initial screening test in patients at high, moderate, and low risk for blunt cervical spine injury: A prospective comparison. J Trauma 2009; 66:1605-1609.
5. Gross EA: CT screening for thoracic and lumbar fractures: Is spine reformatting necessary? Am J Emerg Med 2010; 28:73-75.
6. Como JJ, et al: Practice management guidelines for identification of cervical spine injuries following trauma: Update from the Eastern Association for the Surgery of Trauma practice management guidelines committee. J Trauma 2009; 67:651.
7. Goode, Terral, et al. “Evaluation of cervical spine fracture in the elderly: can we trust our physical examination?." The American Surgeon 80.2 (2014): 182-184.
8. Denver, Dominique, Amith Shetty, and Danielle Unwin. “Falls and implementation of NEXUS in the elderly (The FINE study)." The Journal of emergency medicine 49.3 (2015): 294-300.
9. Pekmezci, Murat, et al. “Cervical spine clearance protocols in Level I, II, and III trauma centers in California." The Spine Journal 15.3 (2015): 398-404.
10. Benayoun, Marc D., et al. “Utility of computed tomography imaging of the cervical spine in trauma evaluation of ground level fall." The journal of trauma and acute care surgery (2016).
11. Rosati, Shannon F., et al. “Implementation of pediatric cervical spine clearance guidelines at a combined trauma center: Twelve-month impact." Journal of Trauma and Acute Care Surgery 78.6 (2015): 1117-1121.
12. Griffith, Brent, et al. “Screening cervical spine CT in the emergency department, phase 2: a prospective assessment of use." American Journal of Neuroradiology 34.4 (2013): 899-903.
13. Hikino, Keiko, and Loren G. Yamamoto. “The benefit of neck computed tomography compared with its harm (risk of cancer)." Journal of Trauma and Acute Care Surgery 78.1 (2015): 126-131.
14. Tipnis, Sameer V., et al. “Thyroid doses and risks to adult patients undergoing neck CT examinations." American Journal of Roentgenology 204.5 (2015): 1064-1068.