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Airbag deployment and cervical spine injury in restrained drivers following motor vehicle collisions

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Purpose Seatbelts and airbags are the most important devices protecting drivers from cervical spine injury (CSI) following motor vehicle collisions (MVCs). However, there have been few reports on the radiographic characteristics of CSI sustained by restrained, airbag-deployed drivers. Methods A single-center, retrospective observational study was conducted using prospectively acquired data. Between January 2011 and December 2017, 564 restrained drivers, whose vehicle had been severely damaged in MVCs, underwent whole-body computed tomography for evaluation of bodily injuries. The drivers were dichotomized into airbag (+) group (n = 218) and airbag (−) group (n = 139), after excluding 207 drivers in whom airbag deployment status was unknown. Results Eight and nine drivers sustained CSIs in the airbag (+) and airbag (−) group, respectively. The frequency of CSI did not differ significantly between the two groups (3.7% vs. 6.5%, p = 0.31). All eight CSIs in the airbag (+) group were classified as hyperextension injuries, and four of them sustained concomitant spinal cord injuries caused by dislocation. Within the airbag (+) group, the drivers with CSIs were significantly older than those without CSIs (65.2 ± 18.5 vs. 44.8 ± 18.7 years, p = 0.002). Conclusion Although it is without doubt that the combination of seatbelt and airbag reduces the frequency and severity of CSIs following MVCs, the CSIs sustained in restrained, airbag (+) drivers may not always be mild, and elderly drivers may be at an elevated risk of CSI. In addition, the possibility of a causal role of airbags in CSI requires consideration in this population.
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SPINAL NEURORADIOLOGY
Airbag deployment and cervical spine injury in restrained drivers
following motor vehicle collisions
Joji Inamasu
1
&Masahiro Kato
2
Received: 3 September 2018 /Accepted: 8 October 2018 /P ublished online: 12 October 2018
#Springer-Verlag GmbH Germany, part of Springer Nature 2018
Abstract
Purpose Seatbelts and airbags are the most important devices protecting drivers from cervicalspine injury (CSI) following motor
vehicle collisions (MVCs). However, there have been few reports on the radiographic characteristics of CSI sustained by
restrained, airbag-deployed drivers.
Methods A single-center, retrospective observational study was conducted using prospectively acquired data. Between January
2011 and December 2017, 564 restrained drivers, whose vehicle had been severely damaged in MVCs, underwent whole-body
computed tomography for evaluation of bodily injuries. The drivers were dichotomized into airbag (+) group (n= 218) and airbag
()group(n= 139), after excluding 207 drivers in whom airbag deployment status was unknown.
Results Eight and nine drivers sustained CSIs in the airbag (+) and airbag () group, respectively. The frequency of CSI did not
differ significantly between the two groups (3.7% vs. 6.5%, p= 0.31). All eight CSIs in the airbag (+) group were classified as
hyperextension injuries, and four of them sustained concomitant spinal cord injuries caused by dislocation. Within the airbag (+)
group, the drivers with CSIs were significantly older than those without CSIs (65.2 ± 18.5 vs. 44.8 ± 18.7 years, p=0.002).
Conclusion Although it is without doubt that the combination of seatbelt and airbag reduces the frequency and severity of CSIs
following MVCs, the CSIs sustained in restrained, airbag (+) drivers may not always be mild, and elderly drivers may be at an
elevated risk of CSI. In addition, the possibility of a causal role of airbags in CSI requires consideration in this population.
Keywords Airbag .Cervical spine injury .Driver .Motor vehicle collision .Seatbelt
Introduction
The characteristics of cervical spine injury (CSI) among drivers
involved in motor vehicle collisions (MVCs) have been repeat-
edly reported [13]. Although seatbelts and airbags are the
most important devices protecting drivers from CSIs [47], it
has rarely been reported how often and in what circumstances
restrained, airbag-deployed drivers sustain a CSI after an MVC.
The use of whole-body computed tomography (WBCT) for
patients suffering from blunt trauma may provide a unique
opportunity to investigate the frequency and characteristics of
CSIinsuchcircumstances[8]. The objective of this study was
to clarify the frequency and the clinical and radiographic char-
acteristics of CSIs sustained by drivers who are restrained and
for whom the airbag has deployed following MVCs.
Materials and methods
This was a single-center, retrospective observational study
using prospectively acquired data. All procedures involving
human participants were in accordance with the ethical stan-
dards of the institutional research committee and with the 1964
Helsinki declaration and its later amendments or comparable
ethical standards. Approval for this study was given by our
institutional research committee. For this type of study (i.e.,
retrospective), formal consent is not required from each patient.
Trauma team activation was initiated on receiving a call
from emergency medicine service (EMS) staff attending to
MVC victims at the scene. Trauma patients were treated ac-
cording to recent guidelines [9]. On their arrival at the emer-
gency department (ED), the temporal sequence of resuscitative
*Joji Inamasu
inamasu@fujita-hu.ac.jp
1
Department of Neurosurgery, Saiseikai Utsunomiya Hospital, 1-98
Takebayashi, Utsunomiya 321-0974, Japan
2
Department of Orthopedic Surgery, Saiseikai Utsunomiya Hospital,
Utsunomiya, Japan
Neuroradiology (2018) 60:13071313
https://doi.org/10.1007/s00234-018-2114-1
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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