Vicky Thi Nguyen MD, Presenter: Nothing to Disclose

Gabriel C. Fine MD, Abstract Co-Author: Nothing to Disclose

Kathleen R. Tozer Fink MD, Abstract Co-Author: Nothing to Disclose

Michael L. Richardson MD, Abstract Co-Author: Nothing to Disclose

Annemarie Relyea-Chew, Abstract Co-Author: Nothing to Disclose

Martin Lee David Gunn MBChB, Abstract Co-Author: Medical Advisor, TransformativeMed, Inc Spouse, Consultant, Wolters Kluwer nv Grant, Koninklijke Philips NV

Blunt carotid and vertebral artery injuries (BCVI) can cause devastating ischemic neurologic events. The Denver criteria are often used to guide BCVI screening and include all patients with C2 fractures (fxs). We hypothesize that patients with ground level falls (GLF) and isolated dens fxs (IDF) have a very low risk of BCVI and do not require vascular imaging.

All patients with C2 fxs in the hospital trauma registry from 2006-2012 were retrospectively reviewed. Age, sex, injury mechanism (GLF or non-GLF, a higher risk mechanism), C2 fracture type (IDF or other C2 fracture (OthC2F)), vascular imaging type, and Biffl injury grade were evaluated.

Of 789 subjects with C2 fxs, 176 (22%) had IDF and 613 (78%) had OthC2F. 538 of 789 (68%) subjects underwent vascular imaging, and 141 (26%) had BCVI. 76 of 176 (43%) patients with IDF underwent vascular imaging and 6 (8%) had BCVI. Of the 31 subjects with type 1 or 2 IDF and vascular imaging, 1 (3%) had BCVI compared to 5/45 (11%) with type 3 IDF. Of the 462 patients with OthC2F and vascular imaging, 135 (29%) had BCVI. There was a significantly decreased prevalence of BCVI in IDF compared to OthC2F (p<0.001). In 31 patients with IDF after GLF who had vascular imaging, only 1 (3%) patient with a type 3 IDF had a BCVI, compared to 35/144 (24%) with OthC2F. Compared to patients with OthC2F and non-GLF, there was an odds ratio of 0.11 for vascular injury in patients with IDF and GLF. There was a significantly decreased risk of BCVI in patients with IDF (p=0.0002) and GLF (p=0.02) compared to patients with OthC2F and non-GLF.  

In patients with vascular imaging, only 8% with IDF had BCVI compared to 29% of those with OthC2F. The rate of BCVI in IDF sustained after GLF is low (1/31), and no patients with type 2 IDF after GLF had BCVI. Thus, these patients may not require routine screening, suggesting the need for further evaluation of the Denver criteria to decrease unnecessary imaging utilization. The rate of BCVI in OthC2F is higher (24-29%) and these patients should be screened regardless of injury mechanism.

Patients with type 2 isolated dens fractures resulting from ground level falls may not require screening for BCVI. Patients with other C2 fractures regardless of mechanism should be screened.

Nguyen, V, Fine, G, Fink, K, Richardson, M, Relyea-Chew, A, Gunn, M, Utility of CTA in Patients with Isolated Dens Fractures.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14004945.html