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Cervical spine immobilization may be of value following firearm injury to the head and neck
American Journal of Emergency Medicine xxx (2016) xxx–xxx
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Brief Report
Cervical spine immobilization may be of value following firearm injury to the head and neck☆,☆☆,★ Sebastian D. Schubl, MD a,⁎, R. Jonathan Robitsek, PhD a, Christian Sommerhalder, MD b, Kimberly J. Wilkins, MD b, Taylor R. Klein, BS a, Scott Trepeta, MD c, Vanessa P. Ho, MD, MPH a,1 a b c
Department of Surgery, Jamaica Hospital Medical Center, Jamaica, NY Ross University School of Medicine, Portsmouth, Dominica Department of Radiology, Jamaica Hospital Medical Center, Jamaica, NY
a r t i c l e
i n f o
Article history: Received 21 November 2015 Received in revised form 11 January 2016 Accepted 13 January 2016 Available online xxxx
a b s t r a c t Background: Penetrating injuries to the head and neck may not be able to cause unstable fractures without concomitant spinal cord injury, rendering prehospital spinal immobilization (PHSI) ineffectual, and possibly harmful. However, this premise is based on reports including predominantly chest and abdominal injuries, which are unlikely to cause cervical spine (CS) injuries. Methods: We performed a retrospective review of all patients presenting with a penetrating wound to the head or neck over a 4-year period at an urban, level 1 trauma center to determine if there was a benefit of PHSI. Results: One hundred seventy-two patients were identified, of which 16 (9.3%) died prior to CS evaluation. Of 156 surviving patients, mechanism was gunshot wound (GSW) in 36 (28%) and stab wound (SW) in 120 (72%). Fifty-eight patients had PHSI placed (37%), and GSW patients' odds of having PHSI were greater than SW patients (OR 2.3; CI 1.08-4.9). Eight of 156 surviving patients eventually died (5.1%), and the odds of mortality were greater among those that had PHSI than those without (OR 5.54; CI 1.08–28.4). Six (3.8%; 5 GSW, 1 SW) patients had a CS fracture. Two GSW patients (5.6%) had unstable CS fractures with a normal neurological exam at initial evaluation. Conclusions: Of patients with a GSW to the head or neck that survived to be evaluated, 5.6% had unstable fractures without an initial neurologic deficit. PHSI may be appropriate in this population. Further studies are warranted prior to a determination that PHSI is unnecessary in penetrating head and neck injuries. © 2016 Elsevier Inc. All rights reserved.
1. Introduction Spinal immobilization has been a standard of prehospital care for decades and is still considered the best and only method for preventing secondary spinal cord injuries (SCI) in the setting of an unstable spinal column. Current PreHospital Trauma Life Support (PHTLS) guidelines and the curriculum of the Advanced Trauma Life Support course of the American College of Surgeons stresses the use of full spinal immobilization in situations where spinal cord injury is suspected [1,2]. These guidelines dominate the instruction of prehospital care personnel and have ☆ Data were originally presented at the Student Section of the American College of Surgeons Clinical Congress in San Francisco, California, October 2014. ☆☆ The study was approved by the Jamaica Hospital Medical Center Institutional Review Board. ★ The authors declare no external funding sources contributed to this research. ⁎ Corresponding author at: Jamaica Hospital Medical Center, 4900 Van Wyck Expressway, Jamaica, NY, 11418. Tel.: +1 718 206 7421; fax: +1 718 206 7428. E-mail addresses: [email protected] (S.D. Schubl), [email protected] (R.J. Robitsek), [email protected] (C. Sommerhalder), [email protected] (K.J. Wilkins), [email protected] (T.R. Klein), [email protected] (S. Trepeta), [email protected] (V.P. Ho). 1 Present Address: Department of Surgery, Division of Trauma, Surgical Critical Care, and Acute Care Surgery, University Hospitals Case Medical Center, Cleveland, Ohio.
spread to 50 to 60 countries world-wide. Recent publications argue that gunshot (GSW) and stab wounds (SW) are not able to contribute to the disruption of the stability of the spinal column without immediate SCI [2]. Thus, risk of a secondary SCI may not exist with a penetrating mechanism of injury and the use of prehospital spinal immobilization (PHSI) is not warranted [3]. Therefore, in penetrating trauma, PHTLS recommends spinal immobilization only when a focal neurologic deficit is present [2]. However, many trauma patients have an altered mental status and therefore an unreliable physical examination due to hypovolemic shock, substance abuse, or other causes. We have found that prehospital personnel are hesitant to forego cervical spine immobilization due to an inability to obtain a reliable neurological exam and examine for focal deficits. Additionally, individual providers anecdotally report cases where spinal immobilization was thought to be helpful. The purpose of this study was to retrospectively review all patients admitted to a Level I trauma center with penetrating injuries of the head, neck, or both and to determine if any patients benefitted from PHSI.
2. Methods Adult patients presenting to an urban Level I trauma center in New York City between January 26, 2010 and January 19, 2014 with a
http://dx.doi.org/10.1016/j.ajem.2016.01.014 0735-6757/© 2016 Elsevier Inc. All rights reserved.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
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S.D. Schubl et al. / American Journal of Emergency Medicine xxx (2016) xxx–xxx
penetrating injury to the head and/or neck (defined as an entry wound superior to the clavicle) were identified utilizing a prospectively maintained trauma registry. Definitions for a neck wound entry were from the clavicles to the skull base whereas definitions for a head wound entry were from the skull base to the top of the calvaria, with neck wounds further classified based on surgical zones. Identified patients were excluded if they were dead on arrival or expired before evaluation of the cervical spine (CS) in the Emergency Department (ED). All medical records were reviewed to verify injuries, clinical and radiologic data, and outcomes. Variables collected included demographics, mechanism and location of injury, PHSI placement status, trauma bay intubation status, injury severity score, Glasgow Coma Scale (GCS), imaging results, presence of CS fracture, presence of neurologic deficits upon arrival, intensive care unit (ICU) admission status, treatments for spine injuries, and mortality. Imaging studies identifying a CS fracture were re-read by the chief neuroradiologist to comment on fracture severity and stability. Data are presented as mean (SD) for continuous variables, median (interquartile range) for ordinal variables, and frequency (percentage) for nominal variables. Comparisons between nominal variables were performed using Pearson's χ2 test, presented with associated odds/risk ratios and 95% confidence intervals. All statistical analyses were performed using R [4].
Table 2 Patient Demographics and Characteristics Stratified by Cervical Collar Status Variable
All Patients
PHSI
No PHSI
p value, PHSI vs No PHSI
Number of Patients Age Injury Severity Score
156 34.5 (15.1) 4 (1–17)
58 (37.2%) 37.2 (16.8) 11 (4–22)
98 (62.8)% 33.7 (13.9) 4 (1–13)
0.0014 0.18 b 0.0001
Location of Wounds Isolated to Head Isolated to Neck Head and Neck
55 (35.2%) 85 (54.5%) 16 (10.3%)
27 (46.6%) 23 (39.7%) 8 (13.8%)
28 (28.6%) 62 (63.3%) 8 (8.2%)
0.02 0.004 0.26
GCS Mild (13–15) Moderate (9–12) Severe (3–8) Admitted to ICU Mortality Post Exam
134 (85.9%) 7 (4.5%) 15 (9.6%) 46 (29.5%) 8 (5.1%)
43 (74.1%) 4 (6.9%) 11 (19.0%) 27 (46.6%) 6 (10.3%)
91 (92.8%) 3 (3.1%) 4 (4.1%) 19 (19.4%) 2 (2.0%)
b 0.0001 0.72 0.002 0.0003 0.031
This table describes analyzed variables, grouped by PHSI placement status (cervical collar vs no cervical collar). All summary statistics presented are based on the parent population (i.e., column wise). Nominal variables are reported as frequency (percentage), continuous variables as mean (standard deviation), and ordinal variables as median (interquartile range). All p values from comparisons between GSW and SW patients for categorical variables based on Chi-square tests (or Fisher's exact test where appropriate); continuous variables were compared using t tests; and ordinal variables were compared using quantile regression. Abbreviations: GSW = gunshot wound; SW = stab wound; GCS = Glasgow Coma Score; ICU = Intensive care unit; PHSI = prehospital spinal immobilization.
3. Results One hundred seventy-two patients were identified, of whom 156 survived to imaging or clinical clearance of their CS (Table 1). Among surviving patients, the average age was 35.0 (15.1) years, with 139 (89%) males, and GSW as mechanism for 36 (28%) and SW for 120 (72%) patients. Isolated neck wounds were most common, accounting for 55% of all patient injuries, followed by isolated head wounds (35%), and combination head and neck wounds (10%; χ 2(2) = 46.04; P b .0001). Of the 156 patients who had CS evaluation, 88 (56%) were cleared without imaging. CS fracture incidence was higher in GSW patients (5/36; 13.9%) than in SW patients (1/120; 0.83%; χ 2(1) = 12.76; P = .003). Four of the 5 GSW patients with CS fracture presented without neurologic deficits. One patient presented with quadriplegia, and 1 Table 1 Patient Demographics and Characteristics Stratified by Injury Mechanism Variable Number of Patients Age Male Injury Severity Score Location of Wounds Isolated to Head Isolated to Neck Head and Neck GCS Mild (13–15) Moderate (9–12) Severe (3–8) Neurologic Deficit Sensory Deficit Motor Deficit PHSI
All Patients
GSW
SW
p value, GSW vs SW
36 (23.1%) 31.7 (11.6) 34 (94%) 19.5 (9.5–49.5)
120 (76.9)% 35.6 (15.9) 105 (87.5%) 4 (1–10)
b 0.0001 0.08 0.39 b 0.0001
55 (35.2%) 85 (54.5%) 16 (10.3%)
25 (69.4%) 6 (16.6%) 5 (14%)
30 (25%) 79 (66%) 11 (9%)
b 0.0001 b 0.0001 0.41
134 (85.9%) 7 (4.5%) 15 (9.6%) 5 (3.2%) 5/141 (3.5%) 6/141 (4.3%) 58 (37.2%)
22 (61.1%) 2 (5.6%) 12 (33.3%) 4 (11.1%) 3 (8.3%) 3 (8.3%) 19 (52.8%)
112 (93.3%) 5 (4.2%) 3 (2.5%) 1 (0.83%) 2 (1.6%) 3 (2.5%) 39 (32.5%)
b 0.0001 0.72 b 0.0001 0.002 0.0464 0.11 0.03
156 34.5 (15.1) 139 (89%) 4 (1–17)
This table describes analyzed variables, grouped by mechanism of injury (GSW vs SW). All summary statistics presented are based on the parent population (i.e., column wise). Nominal variables are reported as frequency (percentage), continuous variables as mean (standard deviation), and ordinal variables as median (interquartile range). All p values from comparisons between GSW and SW patients for categorical variables based on Chisquare tests (or Fisher's exact test where appropriate); continuous variables were compared using t tests; and ordinal variables were compared using quantile regression. Abbreviations: GSW = gunshot wound; SW = stab wound; GCS = Glasgow Coma Score; PHSI = prehospital spinal immobilization.
patient developed neurologic deficits in bilateral upper extremities. Of patients who had clinical or radiologic evaluation of the CS, 8 (5.1%) eventually died, and those that had PHSI were 5.07 times (CI 1.0624.3) more likely to die than those without PHSI (OR 5.54; CI 1.0828.4.Table 2). Whereas patients with a GSW were 2.86 times (CI 2.03–4.04) more likely than those with a SW to have had an isolated injury to the head than the neck, SW patients were 3.7 times (CI 1.8–7.7) more likely than patients with a GSW to have had an isolated injury to the neck than to the head (OR 10.6; CI 3.97–28.38). Among patients with injury to the neck where the anatomic zone of injury was documented (81/ 85; 95%), injuries were most common in zone II (48.1%), followed by zone III (16.0%) and zone I (13.6%; χ 2(5) = 65.7; P b .0001; Table 3). PHSI was placed in 58 (37.2%) patients, with GSW patients 1.6 times (CI 1.08–2.42) more likely than SW patients to have had PHSI placed (OR 2.3; CI 1.08–4.95; Table 1). All patients with neurologic deficiency at the time of presentation to the hospital had PHSI placed. Eleven of 15 patients (73.3%) arriving with a GCS less than 9 had PHSI in place. Twenty-seven (17.3%) patients required intubation in the trauma bay and those with PHSI placed were 4.01 times (CI 1.88–8.57) more likely to require intubation (OR 5.48; CI 2.21–13.58; P b .001). In regards to injury severity, the median injury severity score was significantly higher among those with a GSW as opposed to a SW (19.5 vs 4 respectively; Table 1), and was also higher among patients that had PHSI than those that did not (11 vs 4 respectively; Table 2). Though a minority of all patients were admitted to the ICU (46; 29.5%) the majority of those admitted had PHSI placed (27/46; 59%).
Table 3 Zone of Neck Injury Stratified by Mechanism Zone of Injury
Zone Documented (n = 81)
GSW (n = 10)
SW (n = 71)
Zone I Zone II Zone III Zone I + II Zone II + III Zone I - III
11 (13.6%) 39 (48.1%) 13 (16.0%) 5 (6.2%) 12 (14.8%) 1 (1.2%)
2 (20%) 3 (30%) 4 (40%) 1 (10%) 0 0
9 (12.7%) 36 (50.7%) 9 (12.7%) 4 (5.6%) 12 (16.9%) 1 (1.4%)
Neck zone of injury among patients where injury zone was documented, grouped by injury mechanism (gunshot wound vs stab wound). All summary statistics presented are based on the parent population (i.e., column wise), and data are reported as frequency (percentage).
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
S.D. Schubl et al. / American Journal of Emergency Medicine xxx (2016) xxx–xxx
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Table 4 Injuries and Clinical Descriptions for Patients with Cervical Spine Fracture Patient
Mechanism
Wound Location
Fracture Location
Stable/Unstable
Neuro Exam: Field
Neuro Exam: ED
Disposition
1 2 3 4 5 6
GSW GSW GSW GSW GSW SW
Left Face, Maxillary area Face Face with Zone III Neck exit Zone II of Neck Zone III of Neck Zone II of Neck
C1 Transverse Process C1 Transverse Process C1 Vertebral Arch C5 cord transection C6 superior facet C1-C4 facet C6 teardrop
Stable Stable Unstable Unstable Unstable Stable
Normal Normal Normal GCS 3 Normal Normal
GCS 3 GCS 3 Normal GCS 3 GCS 3 Normal
Transfer; hospital day 1 Deceased; hospital day 1 Home Palliative Care Acute Rehab Home
Clinical presentation, fracture stability, and disposition for all patients with cervical spine fractures.
Six of the 156 surviving patients were diagnosed with CS fractures (3.8%) and are described in Table 4, with representative computed tomographic (CT) images in Figure. Two GSW patients had verified unstable cervical spine fractures with initially normal neurological exams, one of whom developed transient bilateral upper extremity weakness that was managed non-operatively with a hard collar. The second patient required placement of a halo for stabilization. A third patient also had a grossly unstable fracture with quadriplegia at the time of injury that never resolved and expired within days of admission. Only a single patient with a SW had a fracture, which was radiologically diagnosed as a C6 teardrop fracture. In the setting of blunt trauma, the same injury would have been considered unstable as there is usually a concomitant ligamentous injury; however, due to mechanism and a follow-up MRI, no ligamentous injury was identified and this was deemed a stable fracture.
4. Discussion The primary benefit of full spinal immobilization is the prevention of secondary injuries to the spinal cord in the setting of an unstable spinal column injury. This secondary SCI is devastating both clinically and psychologically. The prevailing viewpoint is that penetrating trauma does not cause unstable spine fractures without direct spinal cord injury, making the risk of secondary SCI extremely low [5,6]. Therefore, current PHTLS guidelines suggest that spinal immobilization is not required unless there is focal neurologic deficit [2] in the setting of penetrating trauma to the head, neck, or torso. However, we have found anecdotally that when presented with an unreliable neurological exam in the field, personnel are often hesitant to forego cervical spine immobilization. Some studies conclude that PHSI offers no benefit or is detrimental to patient care [7,8]. The largest review of 75 210 patients published a
Figure. CT imaging of the cervical spine in patients with cervical spine fracture Representative coronal sections from the initial cervical spine CT scan for the 6 patients described in Table 4. Each patient in the figure corresponds to the similarly numbered patient in Table 4.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
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rate of spinal fractures without SCI of 0.03% [9]. However, the majority of patients in that study had torso injuries, thus it is conceivable that the spinal fracture rate may be higher following penetrating trauma to the head and neck. Another report found that CS immobilization in patients with penetrating injury was associated with higher mortality [8], though again this population was not limited to penetrating head and neck trauma. We believe it is important to reexamine this clinical question in the subset of patients with injuries to the head and neck, as SCI in the CS has an extremely morbid and resource-intensive prognosis. Our results concur with the existing literature on patients with SWs to the head or neck: they are unlikely to have unstable cervical spine fractures, and we believe that collars may be avoided in this population. However, we argue that PHSI is potentially important in the delivery of patients with GSWs to the head or neck as the incidence of unstable fractures without deficits is significantly higher than reported elsewhere. Many of our patients were obtunded in the field and trauma bay and were thus initially unevaluable for focal neurological deficits. In such instances, PHSI may be reasonable for short time periods, given the risk of secondary SCI. While our study is limited by its retrospective nature and the small number of GSW patients, that 2 of 36 GSW patients had unstable fractures with a non-focal neurological exam is an important finding, given that this is extremely rare in the literature. Consistent with previous reports, we also find that patients arriving with PHSI had greater odds of death. They also had lower GCS scores upon arrival, higher injury severity scores, a higher ICU admission rate, and a higher intubation rate in the trauma bay. Our study identified the odds of being intubated were higher for patients that had PHSI placed than for those that did not, even though patients with a mild deficit in GCS were more likely to have PHSI placed than those with a severe deficit. That patients presenting with PHSI were more likely to require intubation must be weighed against the need for spinal stabilization and the potential for secondary SCI, as intubation among those with PHSI has been associated with increased difficulty of endotracheal intubation [10], a higher incidence of esophageal intubation events and tube dislodgement, and an overall intubation failure rate of as high as 42% [11]. Spinal immobilization is controversial, as it may be detrimental to patient outcomes in a variety of ways. Firstly, PHSI placement by experienced personnel can increase scene times for transport by an average of 5.64 ± 1.49 minutes [12]. Secondly, concern exists that the presence of PHSI may mask critical injuries and as such, full identification and evaluation of all penetrating injuries can only be achieved after cervical collar removal [13]. Trauma team personnel should evaluate the neck with the collar off immediately upon arrival, and recognize that if a life-threatening injury is identified under a cervical collar, injury control should take precedence over maintaining the collar. As in all trauma scenarios, prioritizing injury management is key in caring for the injured patient. Additional risks associated with PHSI include an increased incidence of skin breakdown in collared trauma patients [14], induction of pain [15], and the capacity to increase intracranial pressure [16], potentially exacerbating brain injury in penetrating head injuries [17,18]. Finally, a review of over 45,000 penetrating trauma patients from the National Trauma Database revealed a higher mortality rate among patients receiving PHSI, although the mechanism of death is unclear [8]. All efforts should be made to remove a cervical collar expeditiously in favor of no collar if there is no injury or definitive treatment in the presence of injury. Our database revealed two patients who had no neurologic symptoms upon presentation that were found to have unstable fractures, with one patient having progression of neurologic symptoms. Outside of our cohort, only a single case report exists of a patient with an unstable CS after penetrating injury without neurologic deficits that required operative fixation [7]. Our two patients did not require operative fixation, but were treated with external stabilization. Despite suggestions
that damage to the spinal cord occurs at the initial impact and that penetrating injuries do not create an unstable spinal column [13,19], our findings suggest there is still a significant role for PHSI in patients who suffer a GSW to the head and/or neck. We would consider providing PHSI for patients with a GSW to the head and/or neck regardless of neurologic deficit until larger studies of this kind can clarify the risk for this patient group. Author Contributions SDS: Study design and conception; data interpretation; manuscript writing. RJR: Data analysis; data interpretation; manuscript editing; figures and tables. CS, KJW, TRK: Chart review and data collection. ST: Radiology re-read for patients with fractures. VPH: Study design and conception; data interpretation; manuscript writing. Acknowledgements The authors would like to thank Dr. Gideon Yoeli for assistance in selecting CT images that best represented the patients' fractures. References [1] ATLS Subcommittee, American College of Surgeons' Committee on Trauma, International ATLS working group. Advanced trauma life support (ATLS®): the ninth edition. J Trauma 2013;74:1363–6. [2] Stuke LE, Pons PT, Guy JS, Chapleau WP, Butler FK, McSwain NE. Prehospital spine immobilization for penetrating trauma–review and recommendations from the prehospital trauma life support executive committee. J Trauma 2011;71:763–9. [3] Harrop JS, Sharan AD, Vaccaro AR, Przybylski GJ. The cause of neurologic deterioration after acute cervical spinal cord injury. Spine 2001;26:340–6. [4] R Development Core Team. R: A language and environment for statistical computing. Version 3.2.0. Vienna, Austria: R Foundation for Statistical Computing; 2015. [5] Lustenberger T, Talving P, Lam L, Kobayashi L, Inaba K, Plurad D, et al. Unstable cervical spine fracture after penetrating neck injury: a rare entity in an analysis of 1,069 patients. J Trauma 2011;70:870–2. [6] Medzon R, Rothenhaus T, Bono CM, Grindlinger G, Rathlev NK. Stability of cervical spine fractures after gunshot wounds to the head and neck. Spine 2005;30:2274–9. [7] Cornwell 3rd EE, Chang DC, Bonar JP, Campbell KA, Phillips J, Lipsett P, et al. Thoracolumbar immobilization for trauma patients with torso gunshot wounds: is it necessary? Arch Surg 2001;136:324–7. [8] Haut ER, Kalish BT, Efron DT, Haider AH, Stevens KA, Kieninger AN, et al. Spine immobilization in penetrating trauma: more harm than good? J Trauma 2010;68: 115–20. [9] Brown JB, Bankey PE, Sangosanya AT, Cheng JD, Stassen NA, Gestring ML. Prehospital spinal immobilization does not appear to be beneficial and may complicate care following gunshot injury to the torso. J Trauma 2009;67:774–8. [10] Kennedy FR, Gonzalez P, Beitler A, Sterling-Scott R, Fleming AW. Incidence of cervical spine injury in patients with gunshot wounds to the head. South Med J 1994;87: 621–3. [11] Kaups KL, Davis JW. Patients with gunshot wounds to the head do not require cervical spine immobilization and evaluation. J Trauma 1998;44:865–7. [12] Arishita GI, Vayer JS, Bellamy RF. Cervical spine immobilization of penetrating neck wounds in a hostile environment. J Trauma 1989;29:332–7. [13] Barkana Y, Stein M, Scope A, Major R, Abramovich Y, Friedman Z, et al. Prehospital stabilization of the cervical spine for penetrating injuries of the neck - is it necessary? Injury 2000;31:305–9. [14] Watts D, Abrahams E, MacMillan C, Sanat J, Silver R, VanGorder S, et al. Insult after injury: pressure ulcers in trauma patients. Orthop Nurs 1998;17:84–91. [15] Chan D, Goldberg R, Tascone A, Harmon S, Chan L. The effect of spinal immobilization on healthy volunteers. Ann Emerg Med 1994;23:48–51. [16] Stone MB, Tubridy CM, Curran R. The effect of rigid cervical collars on internal jugular vein dimensions. Acad Emerg Med 2010;17:100–2. [17] Davies G, Deakin C, Wilson A. The effect of a rigid collar on intracranial pressure. Injury 1996;27:647–9. [18] Hunt K, Hallworth S, Smith M. The effects of rigid collar placement on intracranial and cerebral perfusion pressures. Anaesthesia 2001;56:511–3. [19] Rhee P, Kuncir EJ, Johnson L, Brown C, Velmahos G, Martin M, et al. Cervical spine injury is highly dependent on the mechanism of injury following blunt and penetrating assault. J Trauma 2006;61:1166–70.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Brief Report
Cervical spine immobilization may be of value following firearm injury to the head and neck☆,☆☆,★ Sebastian D. Schubl, MD a,⁎, R. Jonathan Robitsek, PhD a, Christian Sommerhalder, MD b, Kimberly J. Wilkins, MD b, Taylor R. Klein, BS a, Scott Trepeta, MD c, Vanessa P. Ho, MD, MPH a,1 a b c
Department of Surgery, Jamaica Hospital Medical Center, Jamaica, NY Ross University School of Medicine, Portsmouth, Dominica Department of Radiology, Jamaica Hospital Medical Center, Jamaica, NY
a r t i c l e
i n f o
Article history: Received 21 November 2015 Received in revised form 11 January 2016 Accepted 13 January 2016 Available online xxxx
a b s t r a c t Background: Penetrating injuries to the head and neck may not be able to cause unstable fractures without concomitant spinal cord injury, rendering prehospital spinal immobilization (PHSI) ineffectual, and possibly harmful. However, this premise is based on reports including predominantly chest and abdominal injuries, which are unlikely to cause cervical spine (CS) injuries. Methods: We performed a retrospective review of all patients presenting with a penetrating wound to the head or neck over a 4-year period at an urban, level 1 trauma center to determine if there was a benefit of PHSI. Results: One hundred seventy-two patients were identified, of which 16 (9.3%) died prior to CS evaluation. Of 156 surviving patients, mechanism was gunshot wound (GSW) in 36 (28%) and stab wound (SW) in 120 (72%). Fifty-eight patients had PHSI placed (37%), and GSW patients' odds of having PHSI were greater than SW patients (OR 2.3; CI 1.08-4.9). Eight of 156 surviving patients eventually died (5.1%), and the odds of mortality were greater among those that had PHSI than those without (OR 5.54; CI 1.08–28.4). Six (3.8%; 5 GSW, 1 SW) patients had a CS fracture. Two GSW patients (5.6%) had unstable CS fractures with a normal neurological exam at initial evaluation. Conclusions: Of patients with a GSW to the head or neck that survived to be evaluated, 5.6% had unstable fractures without an initial neurologic deficit. PHSI may be appropriate in this population. Further studies are warranted prior to a determination that PHSI is unnecessary in penetrating head and neck injuries. © 2016 Elsevier Inc. All rights reserved.
1. Introduction Spinal immobilization has been a standard of prehospital care for decades and is still considered the best and only method for preventing secondary spinal cord injuries (SCI) in the setting of an unstable spinal column. Current PreHospital Trauma Life Support (PHTLS) guidelines and the curriculum of the Advanced Trauma Life Support course of the American College of Surgeons stresses the use of full spinal immobilization in situations where spinal cord injury is suspected [1,2]. These guidelines dominate the instruction of prehospital care personnel and have ☆ Data were originally presented at the Student Section of the American College of Surgeons Clinical Congress in San Francisco, California, October 2014. ☆☆ The study was approved by the Jamaica Hospital Medical Center Institutional Review Board. ★ The authors declare no external funding sources contributed to this research. ⁎ Corresponding author at: Jamaica Hospital Medical Center, 4900 Van Wyck Expressway, Jamaica, NY, 11418. Tel.: +1 718 206 7421; fax: +1 718 206 7428. E-mail addresses: [email protected] (S.D. Schubl), [email protected] (R.J. Robitsek), [email protected] (C. Sommerhalder), [email protected] (K.J. Wilkins), [email protected] (T.R. Klein), [email protected] (S. Trepeta), [email protected] (V.P. Ho). 1 Present Address: Department of Surgery, Division of Trauma, Surgical Critical Care, and Acute Care Surgery, University Hospitals Case Medical Center, Cleveland, Ohio.
spread to 50 to 60 countries world-wide. Recent publications argue that gunshot (GSW) and stab wounds (SW) are not able to contribute to the disruption of the stability of the spinal column without immediate SCI [2]. Thus, risk of a secondary SCI may not exist with a penetrating mechanism of injury and the use of prehospital spinal immobilization (PHSI) is not warranted [3]. Therefore, in penetrating trauma, PHTLS recommends spinal immobilization only when a focal neurologic deficit is present [2]. However, many trauma patients have an altered mental status and therefore an unreliable physical examination due to hypovolemic shock, substance abuse, or other causes. We have found that prehospital personnel are hesitant to forego cervical spine immobilization due to an inability to obtain a reliable neurological exam and examine for focal deficits. Additionally, individual providers anecdotally report cases where spinal immobilization was thought to be helpful. The purpose of this study was to retrospectively review all patients admitted to a Level I trauma center with penetrating injuries of the head, neck, or both and to determine if any patients benefitted from PHSI.
2. Methods Adult patients presenting to an urban Level I trauma center in New York City between January 26, 2010 and January 19, 2014 with a
http://dx.doi.org/10.1016/j.ajem.2016.01.014 0735-6757/© 2016 Elsevier Inc. All rights reserved.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
2
S.D. Schubl et al. / American Journal of Emergency Medicine xxx (2016) xxx–xxx
penetrating injury to the head and/or neck (defined as an entry wound superior to the clavicle) were identified utilizing a prospectively maintained trauma registry. Definitions for a neck wound entry were from the clavicles to the skull base whereas definitions for a head wound entry were from the skull base to the top of the calvaria, with neck wounds further classified based on surgical zones. Identified patients were excluded if they were dead on arrival or expired before evaluation of the cervical spine (CS) in the Emergency Department (ED). All medical records were reviewed to verify injuries, clinical and radiologic data, and outcomes. Variables collected included demographics, mechanism and location of injury, PHSI placement status, trauma bay intubation status, injury severity score, Glasgow Coma Scale (GCS), imaging results, presence of CS fracture, presence of neurologic deficits upon arrival, intensive care unit (ICU) admission status, treatments for spine injuries, and mortality. Imaging studies identifying a CS fracture were re-read by the chief neuroradiologist to comment on fracture severity and stability. Data are presented as mean (SD) for continuous variables, median (interquartile range) for ordinal variables, and frequency (percentage) for nominal variables. Comparisons between nominal variables were performed using Pearson's χ2 test, presented with associated odds/risk ratios and 95% confidence intervals. All statistical analyses were performed using R [4].
Table 2 Patient Demographics and Characteristics Stratified by Cervical Collar Status Variable
All Patients
PHSI
No PHSI
p value, PHSI vs No PHSI
Number of Patients Age Injury Severity Score
156 34.5 (15.1) 4 (1–17)
58 (37.2%) 37.2 (16.8) 11 (4–22)
98 (62.8)% 33.7 (13.9) 4 (1–13)
0.0014 0.18 b 0.0001
Location of Wounds Isolated to Head Isolated to Neck Head and Neck
55 (35.2%) 85 (54.5%) 16 (10.3%)
27 (46.6%) 23 (39.7%) 8 (13.8%)
28 (28.6%) 62 (63.3%) 8 (8.2%)
0.02 0.004 0.26
GCS Mild (13–15) Moderate (9–12) Severe (3–8) Admitted to ICU Mortality Post Exam
134 (85.9%) 7 (4.5%) 15 (9.6%) 46 (29.5%) 8 (5.1%)
43 (74.1%) 4 (6.9%) 11 (19.0%) 27 (46.6%) 6 (10.3%)
91 (92.8%) 3 (3.1%) 4 (4.1%) 19 (19.4%) 2 (2.0%)
b 0.0001 0.72 0.002 0.0003 0.031
This table describes analyzed variables, grouped by PHSI placement status (cervical collar vs no cervical collar). All summary statistics presented are based on the parent population (i.e., column wise). Nominal variables are reported as frequency (percentage), continuous variables as mean (standard deviation), and ordinal variables as median (interquartile range). All p values from comparisons between GSW and SW patients for categorical variables based on Chi-square tests (or Fisher's exact test where appropriate); continuous variables were compared using t tests; and ordinal variables were compared using quantile regression. Abbreviations: GSW = gunshot wound; SW = stab wound; GCS = Glasgow Coma Score; ICU = Intensive care unit; PHSI = prehospital spinal immobilization.
3. Results One hundred seventy-two patients were identified, of whom 156 survived to imaging or clinical clearance of their CS (Table 1). Among surviving patients, the average age was 35.0 (15.1) years, with 139 (89%) males, and GSW as mechanism for 36 (28%) and SW for 120 (72%) patients. Isolated neck wounds were most common, accounting for 55% of all patient injuries, followed by isolated head wounds (35%), and combination head and neck wounds (10%; χ 2(2) = 46.04; P b .0001). Of the 156 patients who had CS evaluation, 88 (56%) were cleared without imaging. CS fracture incidence was higher in GSW patients (5/36; 13.9%) than in SW patients (1/120; 0.83%; χ 2(1) = 12.76; P = .003). Four of the 5 GSW patients with CS fracture presented without neurologic deficits. One patient presented with quadriplegia, and 1 Table 1 Patient Demographics and Characteristics Stratified by Injury Mechanism Variable Number of Patients Age Male Injury Severity Score Location of Wounds Isolated to Head Isolated to Neck Head and Neck GCS Mild (13–15) Moderate (9–12) Severe (3–8) Neurologic Deficit Sensory Deficit Motor Deficit PHSI
All Patients
GSW
SW
p value, GSW vs SW
36 (23.1%) 31.7 (11.6) 34 (94%) 19.5 (9.5–49.5)
120 (76.9)% 35.6 (15.9) 105 (87.5%) 4 (1–10)
b 0.0001 0.08 0.39 b 0.0001
55 (35.2%) 85 (54.5%) 16 (10.3%)
25 (69.4%) 6 (16.6%) 5 (14%)
30 (25%) 79 (66%) 11 (9%)
b 0.0001 b 0.0001 0.41
134 (85.9%) 7 (4.5%) 15 (9.6%) 5 (3.2%) 5/141 (3.5%) 6/141 (4.3%) 58 (37.2%)
22 (61.1%) 2 (5.6%) 12 (33.3%) 4 (11.1%) 3 (8.3%) 3 (8.3%) 19 (52.8%)
112 (93.3%) 5 (4.2%) 3 (2.5%) 1 (0.83%) 2 (1.6%) 3 (2.5%) 39 (32.5%)
b 0.0001 0.72 b 0.0001 0.002 0.0464 0.11 0.03
156 34.5 (15.1) 139 (89%) 4 (1–17)
This table describes analyzed variables, grouped by mechanism of injury (GSW vs SW). All summary statistics presented are based on the parent population (i.e., column wise). Nominal variables are reported as frequency (percentage), continuous variables as mean (standard deviation), and ordinal variables as median (interquartile range). All p values from comparisons between GSW and SW patients for categorical variables based on Chisquare tests (or Fisher's exact test where appropriate); continuous variables were compared using t tests; and ordinal variables were compared using quantile regression. Abbreviations: GSW = gunshot wound; SW = stab wound; GCS = Glasgow Coma Score; PHSI = prehospital spinal immobilization.
patient developed neurologic deficits in bilateral upper extremities. Of patients who had clinical or radiologic evaluation of the CS, 8 (5.1%) eventually died, and those that had PHSI were 5.07 times (CI 1.0624.3) more likely to die than those without PHSI (OR 5.54; CI 1.0828.4.Table 2). Whereas patients with a GSW were 2.86 times (CI 2.03–4.04) more likely than those with a SW to have had an isolated injury to the head than the neck, SW patients were 3.7 times (CI 1.8–7.7) more likely than patients with a GSW to have had an isolated injury to the neck than to the head (OR 10.6; CI 3.97–28.38). Among patients with injury to the neck where the anatomic zone of injury was documented (81/ 85; 95%), injuries were most common in zone II (48.1%), followed by zone III (16.0%) and zone I (13.6%; χ 2(5) = 65.7; P b .0001; Table 3). PHSI was placed in 58 (37.2%) patients, with GSW patients 1.6 times (CI 1.08–2.42) more likely than SW patients to have had PHSI placed (OR 2.3; CI 1.08–4.95; Table 1). All patients with neurologic deficiency at the time of presentation to the hospital had PHSI placed. Eleven of 15 patients (73.3%) arriving with a GCS less than 9 had PHSI in place. Twenty-seven (17.3%) patients required intubation in the trauma bay and those with PHSI placed were 4.01 times (CI 1.88–8.57) more likely to require intubation (OR 5.48; CI 2.21–13.58; P b .001). In regards to injury severity, the median injury severity score was significantly higher among those with a GSW as opposed to a SW (19.5 vs 4 respectively; Table 1), and was also higher among patients that had PHSI than those that did not (11 vs 4 respectively; Table 2). Though a minority of all patients were admitted to the ICU (46; 29.5%) the majority of those admitted had PHSI placed (27/46; 59%).
Table 3 Zone of Neck Injury Stratified by Mechanism Zone of Injury
Zone Documented (n = 81)
GSW (n = 10)
SW (n = 71)
Zone I Zone II Zone III Zone I + II Zone II + III Zone I - III
11 (13.6%) 39 (48.1%) 13 (16.0%) 5 (6.2%) 12 (14.8%) 1 (1.2%)
2 (20%) 3 (30%) 4 (40%) 1 (10%) 0 0
9 (12.7%) 36 (50.7%) 9 (12.7%) 4 (5.6%) 12 (16.9%) 1 (1.4%)
Neck zone of injury among patients where injury zone was documented, grouped by injury mechanism (gunshot wound vs stab wound). All summary statistics presented are based on the parent population (i.e., column wise), and data are reported as frequency (percentage).
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
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Table 4 Injuries and Clinical Descriptions for Patients with Cervical Spine Fracture Patient
Mechanism
Wound Location
Fracture Location
Stable/Unstable
Neuro Exam: Field
Neuro Exam: ED
Disposition
1 2 3 4 5 6
GSW GSW GSW GSW GSW SW
Left Face, Maxillary area Face Face with Zone III Neck exit Zone II of Neck Zone III of Neck Zone II of Neck
C1 Transverse Process C1 Transverse Process C1 Vertebral Arch C5 cord transection C6 superior facet C1-C4 facet C6 teardrop
Stable Stable Unstable Unstable Unstable Stable
Normal Normal Normal GCS 3 Normal Normal
GCS 3 GCS 3 Normal GCS 3 GCS 3 Normal
Transfer; hospital day 1 Deceased; hospital day 1 Home Palliative Care Acute Rehab Home
Clinical presentation, fracture stability, and disposition for all patients with cervical spine fractures.
Six of the 156 surviving patients were diagnosed with CS fractures (3.8%) and are described in Table 4, with representative computed tomographic (CT) images in Figure. Two GSW patients had verified unstable cervical spine fractures with initially normal neurological exams, one of whom developed transient bilateral upper extremity weakness that was managed non-operatively with a hard collar. The second patient required placement of a halo for stabilization. A third patient also had a grossly unstable fracture with quadriplegia at the time of injury that never resolved and expired within days of admission. Only a single patient with a SW had a fracture, which was radiologically diagnosed as a C6 teardrop fracture. In the setting of blunt trauma, the same injury would have been considered unstable as there is usually a concomitant ligamentous injury; however, due to mechanism and a follow-up MRI, no ligamentous injury was identified and this was deemed a stable fracture.
4. Discussion The primary benefit of full spinal immobilization is the prevention of secondary injuries to the spinal cord in the setting of an unstable spinal column injury. This secondary SCI is devastating both clinically and psychologically. The prevailing viewpoint is that penetrating trauma does not cause unstable spine fractures without direct spinal cord injury, making the risk of secondary SCI extremely low [5,6]. Therefore, current PHTLS guidelines suggest that spinal immobilization is not required unless there is focal neurologic deficit [2] in the setting of penetrating trauma to the head, neck, or torso. However, we have found anecdotally that when presented with an unreliable neurological exam in the field, personnel are often hesitant to forego cervical spine immobilization. Some studies conclude that PHSI offers no benefit or is detrimental to patient care [7,8]. The largest review of 75 210 patients published a
Figure. CT imaging of the cervical spine in patients with cervical spine fracture Representative coronal sections from the initial cervical spine CT scan for the 6 patients described in Table 4. Each patient in the figure corresponds to the similarly numbered patient in Table 4.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014
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rate of spinal fractures without SCI of 0.03% [9]. However, the majority of patients in that study had torso injuries, thus it is conceivable that the spinal fracture rate may be higher following penetrating trauma to the head and neck. Another report found that CS immobilization in patients with penetrating injury was associated with higher mortality [8], though again this population was not limited to penetrating head and neck trauma. We believe it is important to reexamine this clinical question in the subset of patients with injuries to the head and neck, as SCI in the CS has an extremely morbid and resource-intensive prognosis. Our results concur with the existing literature on patients with SWs to the head or neck: they are unlikely to have unstable cervical spine fractures, and we believe that collars may be avoided in this population. However, we argue that PHSI is potentially important in the delivery of patients with GSWs to the head or neck as the incidence of unstable fractures without deficits is significantly higher than reported elsewhere. Many of our patients were obtunded in the field and trauma bay and were thus initially unevaluable for focal neurological deficits. In such instances, PHSI may be reasonable for short time periods, given the risk of secondary SCI. While our study is limited by its retrospective nature and the small number of GSW patients, that 2 of 36 GSW patients had unstable fractures with a non-focal neurological exam is an important finding, given that this is extremely rare in the literature. Consistent with previous reports, we also find that patients arriving with PHSI had greater odds of death. They also had lower GCS scores upon arrival, higher injury severity scores, a higher ICU admission rate, and a higher intubation rate in the trauma bay. Our study identified the odds of being intubated were higher for patients that had PHSI placed than for those that did not, even though patients with a mild deficit in GCS were more likely to have PHSI placed than those with a severe deficit. That patients presenting with PHSI were more likely to require intubation must be weighed against the need for spinal stabilization and the potential for secondary SCI, as intubation among those with PHSI has been associated with increased difficulty of endotracheal intubation [10], a higher incidence of esophageal intubation events and tube dislodgement, and an overall intubation failure rate of as high as 42% [11]. Spinal immobilization is controversial, as it may be detrimental to patient outcomes in a variety of ways. Firstly, PHSI placement by experienced personnel can increase scene times for transport by an average of 5.64 ± 1.49 minutes [12]. Secondly, concern exists that the presence of PHSI may mask critical injuries and as such, full identification and evaluation of all penetrating injuries can only be achieved after cervical collar removal [13]. Trauma team personnel should evaluate the neck with the collar off immediately upon arrival, and recognize that if a life-threatening injury is identified under a cervical collar, injury control should take precedence over maintaining the collar. As in all trauma scenarios, prioritizing injury management is key in caring for the injured patient. Additional risks associated with PHSI include an increased incidence of skin breakdown in collared trauma patients [14], induction of pain [15], and the capacity to increase intracranial pressure [16], potentially exacerbating brain injury in penetrating head injuries [17,18]. Finally, a review of over 45,000 penetrating trauma patients from the National Trauma Database revealed a higher mortality rate among patients receiving PHSI, although the mechanism of death is unclear [8]. All efforts should be made to remove a cervical collar expeditiously in favor of no collar if there is no injury or definitive treatment in the presence of injury. Our database revealed two patients who had no neurologic symptoms upon presentation that were found to have unstable fractures, with one patient having progression of neurologic symptoms. Outside of our cohort, only a single case report exists of a patient with an unstable CS after penetrating injury without neurologic deficits that required operative fixation [7]. Our two patients did not require operative fixation, but were treated with external stabilization. Despite suggestions
that damage to the spinal cord occurs at the initial impact and that penetrating injuries do not create an unstable spinal column [13,19], our findings suggest there is still a significant role for PHSI in patients who suffer a GSW to the head and/or neck. We would consider providing PHSI for patients with a GSW to the head and/or neck regardless of neurologic deficit until larger studies of this kind can clarify the risk for this patient group. Author Contributions SDS: Study design and conception; data interpretation; manuscript writing. RJR: Data analysis; data interpretation; manuscript editing; figures and tables. CS, KJW, TRK: Chart review and data collection. ST: Radiology re-read for patients with fractures. VPH: Study design and conception; data interpretation; manuscript writing. Acknowledgements The authors would like to thank Dr. Gideon Yoeli for assistance in selecting CT images that best represented the patients' fractures. References [1] ATLS Subcommittee, American College of Surgeons' Committee on Trauma, International ATLS working group. Advanced trauma life support (ATLS®): the ninth edition. J Trauma 2013;74:1363–6. [2] Stuke LE, Pons PT, Guy JS, Chapleau WP, Butler FK, McSwain NE. Prehospital spine immobilization for penetrating trauma–review and recommendations from the prehospital trauma life support executive committee. J Trauma 2011;71:763–9. [3] Harrop JS, Sharan AD, Vaccaro AR, Przybylski GJ. The cause of neurologic deterioration after acute cervical spinal cord injury. Spine 2001;26:340–6. [4] R Development Core Team. R: A language and environment for statistical computing. Version 3.2.0. Vienna, Austria: R Foundation for Statistical Computing; 2015. [5] Lustenberger T, Talving P, Lam L, Kobayashi L, Inaba K, Plurad D, et al. Unstable cervical spine fracture after penetrating neck injury: a rare entity in an analysis of 1,069 patients. J Trauma 2011;70:870–2. [6] Medzon R, Rothenhaus T, Bono CM, Grindlinger G, Rathlev NK. Stability of cervical spine fractures after gunshot wounds to the head and neck. Spine 2005;30:2274–9. [7] Cornwell 3rd EE, Chang DC, Bonar JP, Campbell KA, Phillips J, Lipsett P, et al. Thoracolumbar immobilization for trauma patients with torso gunshot wounds: is it necessary? Arch Surg 2001;136:324–7. [8] Haut ER, Kalish BT, Efron DT, Haider AH, Stevens KA, Kieninger AN, et al. Spine immobilization in penetrating trauma: more harm than good? J Trauma 2010;68: 115–20. [9] Brown JB, Bankey PE, Sangosanya AT, Cheng JD, Stassen NA, Gestring ML. Prehospital spinal immobilization does not appear to be beneficial and may complicate care following gunshot injury to the torso. J Trauma 2009;67:774–8. [10] Kennedy FR, Gonzalez P, Beitler A, Sterling-Scott R, Fleming AW. Incidence of cervical spine injury in patients with gunshot wounds to the head. South Med J 1994;87: 621–3. [11] Kaups KL, Davis JW. Patients with gunshot wounds to the head do not require cervical spine immobilization and evaluation. J Trauma 1998;44:865–7. [12] Arishita GI, Vayer JS, Bellamy RF. Cervical spine immobilization of penetrating neck wounds in a hostile environment. J Trauma 1989;29:332–7. [13] Barkana Y, Stein M, Scope A, Major R, Abramovich Y, Friedman Z, et al. Prehospital stabilization of the cervical spine for penetrating injuries of the neck - is it necessary? Injury 2000;31:305–9. [14] Watts D, Abrahams E, MacMillan C, Sanat J, Silver R, VanGorder S, et al. Insult after injury: pressure ulcers in trauma patients. Orthop Nurs 1998;17:84–91. [15] Chan D, Goldberg R, Tascone A, Harmon S, Chan L. The effect of spinal immobilization on healthy volunteers. Ann Emerg Med 1994;23:48–51. [16] Stone MB, Tubridy CM, Curran R. The effect of rigid cervical collars on internal jugular vein dimensions. Acad Emerg Med 2010;17:100–2. [17] Davies G, Deakin C, Wilson A. The effect of a rigid collar on intracranial pressure. Injury 1996;27:647–9. [18] Hunt K, Hallworth S, Smith M. The effects of rigid collar placement on intracranial and cerebral perfusion pressures. Anaesthesia 2001;56:511–3. [19] Rhee P, Kuncir EJ, Johnson L, Brown C, Velmahos G, Martin M, et al. Cervical spine injury is highly dependent on the mechanism of injury following blunt and penetrating assault. J Trauma 2006;61:1166–70.
Please cite this article as: Schubl SD, et al, Cervical spine immobilization may be of value following firearm injury to the head and neck, Am J Emerg Med (2016), http://dx.doi.org/10.1016/j.ajem.2016.01.014