Wartime spine injuries: understanding the improvised explosive device
and biophysics of blast trauma
Daniel G. Kang, MDa, Ronald A. Lehman, Jr., MDa,b,*, Eugene J. Carragee, MDc
aDepartment of Orthopaedic Surgery and Rehabilitation, Walter Reed National Military Medical Center, 8901 Wisconsin Ave, Bethesda, MD 20889, USA
bDivision of Orthopaedics, Department of Surgery, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD 20814, USA
cDepartment of Orthopedic Surgery, Stanford University Medical Center, Stanford, CA 94305, USA
Received 9 September 2011; revised 2 November 2011; accepted 15 November 2011
AbstractThe improvised explosive device (IED) has been the most significant threat by terrorists worldwide.
in the civilian community. Unfortunately, explosion-related injuries have also become a widespread
reality of civilian life throughout theworld, and civilian medical providers who are involvedin emer-
gencytraumacare mustbepreparedtomanage casualtiesfromterrorist attacksusinghigh-energyex-
plosive devices. Treatment decisions for complex spine injuries after blast trauma require special
planning,takinginto considerationmanydifferent factors andthe complicated multiple organsystem
injuries not normally experienced at most civilian trauma centers. Therefore, an understanding about
the effects of blast trauma by spine surgeons in the community has become imperative, as the battle-
situations, withthe linesblurred between military andcivilian trauma. Weset outto provide the spine
surgeon with a brief overview on the use of IEDs for terrorism and the current conflicts in Iraq and
Afghanistan and also a perspective on the biophysics of blast trauma. Published by Elsevier Inc.
Keywords: Improvised explosive device; Blast trauma; Blast injury; Blast biophysics; Combat spine injury; Wartime spine
The improvised explosive device (IED) has been the
most significant threat by terrorists worldwide and is the
leading cause of injury and death for servicemembers oper-
ating in Afghanistan and Iraq. To date, there have been
more than 50,000 coalition forces injured or killed by ex-
plosive devices [1,2]. There has also been a 19% increase
in IED-related coalition force casualties in Afghanistan
during 2010, which has been the result of increased opera-
tional tempo, increased volume of IED placement by insur-
gent forces, and evolving insurgent doctrine with specific
targeting of dismounted forces and increased use of suicide
bombs [1,3]. Improvised explosive devices often require
limited skill and technology and allow devastating attacks
for a relatively small investment.
Exposure of servicemembers to high-energy blast
trauma has brought unique challenges in the treatment of
wartime spine injuries. Special considerations are necessary
after high-energy blast trauma, and a multidisciplinary
team is required to care for combat casualties with
FDA device/drug status: Not applicable.
Author disclosures: DGK: Nothing to disclose. RAL: Grants: DARPA
(G, Paid directly to institution/employer), DMRDP (H, Paid directly to in-
stitution/employer). EJC: Stock Ownership: Intrinsic Spine (B), Cytonics
(B), Bioassetts (B); Private Investments: Simpirica (D); Consulting: US
Department of Justice (D), Kaiser Permanente (D), US Army (Trips/Travel
disclosed), US Department of Defense (Trips/Travel disclosed); Research
Support (Investigator Salary): NIH (C, Paid directly to institution/
employer); Trips/Travel: US Army (B), Department of Defense (A), Ortho-
paedic Trauma Society (A), OREF (B), AAOS (A), NASS (A), The Spine
Journal (A); Other Office: NASS/The Spine Journal (E, Editor in Chief);
Fellowship Support: OREF (E, Paid directly to institution/employer), AO
Foundation (E, Paid directly to institution/employer).
The disclosure key can be found on the Table of Contents and at www.
The views expressed in this article are those of the authors and do not
reflect the official policy of the Department of Army, Department of
Defense, or US Government. Authors are employees of the US govern-
ment. This work was prepared as part of their official duties, and as such,
there is no copyright to be transferred.
* Corresponding author. Department of Orthopaedic Surgery and
Rehabilitation, Walter Reed National Military Medical Center, 8901 Wis-
consin Ave, Bethesda, MD 20889, USA. Tel.: (301) 295-6550; fax: (301)
E-mail address: firstname.lastname@example.org (R.A. Lehman)
1529-9430/$ - see front matter Published by Elsevier Inc.
The Spine Journal - (2012) -
complicated multiple organ system injuries. These injuries
often involve a combination of highly contaminated ex-
tremity injuries and amputations, traumatic brain injury,
and thoracic and visceral injuries [2,4–10] (Fig. 1). Combat
casualties have also sustained an increased incidence of un-
common spine injury patterns, including chance fractures
, low lumbar burst fractures, and lumbosacral dissocia-
tion injuries , (Fig. 2) as well as spine injuries associated
with large degloving (Morel-Lavallee) or highly contami-
nated soft-tissue wounds. Although spine injuries are com-
monly encountered in civilian trauma, there have been few
civilian trauma centers and spine surgeons experienced
with the treatment of complex spine injuries after blast
trauma. Therefore, treatment decisions for spine injuries
after blast trauma require special planning, taking into con-
sideration many different factors not normally encountered
at most civilian trauma centers.
The treatment of high-energy wartime spine trauma has
been extrapolated from the civilian trauma literature, with
regard to their experience treating patients after motor
vehicle collisions or falls from a height [12–15]. However,
the tremendous energy imparted by an IED explosion is
considerably different from civilian injury mechanisms
and even from other injuries incurred during combat such
as gunshot wounds or vehicular accidents. Improvised
explosive devices were responsible for more than 60% of
US combat casualties during the Iraq conflict; however,
nearly nine of 10 casualties survived [7,16,17]. This
10.1% case fatality rate is the lowest in history, compared
with ground forces during World War II and Vietnam,
which were 19.1% and 15.7%, respectively [16,17]. The
decline in case fatality is likely multifactorial and may be
a result of improvements in modern body armor, frontline
battlefield care, far-forward placement of surgical teams,
advances in intensive care and surgical capabilities, and
significantly decreased medical evacuation times [16,18].
Although most IED attacks occur as a result of military
conflict, surprisingly a land mine casualty occurs every
20 minutes and an average of 260 IED incidents per month
outside the areas of conflict in Afghanistan and Iraq [3,19].
In addition, just within the United States, there was an av-
erage of 205 casualties per year between 2004 and 2006
from criminal bombing incidents . Despite these statis-
tics, most civilian medical providers have limited experi-
ence with blast-related injuries, and it is conceivable that
they may be called on to manage casualties after an IED
attack [16,20,21]. Therefore, we set out to provide the spine
surgeon with a brief overview on the use of IEDs for terror-
ism and the current conflicts in Iraq and Afghanistan and
also a perspective on the biophysics of blast trauma.
Understanding the IED
The US Department of Defense has broadly defined an
IED as a ‘‘device placed or fabricatedin an improvised man-
incendiary chemicals, designed to destroy, disfigure, or
harass .’’ . Improvised explosive devices not only in-
flict devastating injuries but are also used to intimidate local
populations, challenge legitimate government authority, and
restrict or slow coalition force freedom of movement .
Terrorist groups have easy access to commercial technolo-
gies, training via the Internet, the ability to manufacture or
procure explosive materials, improvement in coordination/
communication, and expansive financial support networks
to continue their IED campaigns . However, a common
misconception is that IEDs are limited to crude homemade
explosives placed on roadsides to target military convoys.
The term ‘‘IED’’ encompasses a wide spectrum of explosive
weapons, ranging from rudimentary homemade explosives
or unused artillery rounds to sophisticated weapon systems
and triggering devices containing high-grade explosives
The various forms of IEDs have become increasingly
lethal, while providing the enemy with standoff, precision
lethality and near total anonymity . However, all explo-
sive devices, regardless of their use, are characterized by
three elements: a fusing mechanism, explosive mixture,
and casing . The fusing element allows controlled
Fig. 1. Combat casualty after improvised explosive device attack, sus-
tained bilateral lower extremity amputation (Top), open lumbar and sacral
spine fractures, and severe soft-tissue wounds to gluteal and presacral re-
2 D.G. Kang et al. / The Spine Journal - (2012) -
initiation for the blast, and insurgents have used techniques
such as boosting, coupling, and daisy chaining to increase
the lethality of IEDs. Boosting involves fusing multiple
buried IEDs, stacked on top of one another to increase
the upward force of a blast. Coupling is a method used to
link the initiation of multiple IED explosions to increase
the maximum effective radius, a term used to describe the
distance at which casualties can be expected . Daisy
chaining describes sequential initiation of multiple IED ex-
plosions and allows a vehicle with a mine roller device to
first pass over multiple sequentially fused explosive devices
without causing detonation (Fig. 3). Once a trigger IED is
reached and detonated by the mine roller device, a ‘‘daisy
chain’’ of explosions of overpassed IEDs underneath the
vehicle or convoy of vehicles is initiated .
Second, the explosive mixture provides the energy for
the blast, and the type and amount of explosive mixture in-
corporated into the IED principally determines its destruc-
tive power [19,24]. The power of an explosive is often
rated in terms of its explosive equivalent to trinitrotoluene
(TNT) . There is a large spectrum of explosive mixtures,
including solids and liquids, and differences in explosive
mixtures are largely regional and based on supply and tech-
nology (Table 1) [1,20,22,25,26]. Previously, ammonium ni-
trate/fuel oil was a readily available explosive mixture in
Afghanistan; however, recent countermeasures by coalition
and local security forces have banned its production .
The third component of an IED device is the casing. The
stochastic injury pattern of each individual IED is largely
because of the bomb casing and modifications made by in-
surgents and terrorists to maximize fragmentation .
Conventional military ordinance propels fragments created
by the breakup of the metal casing surrounding the explo-
sive. In contrast, IEDs have been purposely designed to in-
crease destructive power through secondary projectiles and
fragments by incorporating metal objects, such as nails,
nuts, bolts, or ball bearings, packed inside or around the ex-
plosive device [1,19]. Terrorists and insurgents have also
used vehicle-borne IEDs as another method to increase
fragmentation injury because of the breakup of the vehicle
during the explosion and also because larger amounts of ex-
plosive material can be placed into the vehicle versus other
casings or containers.
Another specially designed IED that deserves mention is
the explosively formed penetrator, which has been a promi-
nent feature of military operations during the Iraq conflict.
Also termed a ‘‘shape charge,’’ an explosively formed pen-
etrator involves the use of an explosive device to propel
a metal projectile at a significant velocity allowing penetra-
tion into an armored vehicle [1,22,27,28]. A typical explo-
sively formed penetrator involves a cylindrical casing filled
with explosive material, capped with either a saucer-shaped
or conical piece of metal . Detonation of the explosive
material causes the metal cap to become a molten
Fig. 2. Computed tomography demonstrating lumbosacral dissociation injury. Axial (Top) and coronal reconstruction images (Bottom).
Fig. 3. Illustration of daisy chain method of improvised explosive device detonation to counteract mine roller device.
3 D.G. Kang et al. / The Spine Journal - (2012) -
projectile, propelled by a high-pressure wave (up to 30 mil-
lion psi) along the axis of symmetry of the cylindrical cas-
ing, accelerating it up to velocities of 6,600 mph . On
impact with an armored vehicle, the projectile ‘‘penetrates’’
the target and dissipates a significant amount of kinetic
Another tactic used by insurgents and terrorists to maxi-
mize casualties involves complex multistaged ambushes and
explosions, which were devised after studying coalition force
combat doctrine. An example includes the use of secondary
IEDs in which a military convoy or patrol is brought to a halt
with an initial IED blast, and after troops dismount from the
ful IED is detonated. Insurgents and terrorists have also at-
tacked targets of opportunity, such as medical personnel and
evacuation helicopters, by identifying potential casualty col-
or ambushing these areas during medical evacuation .
And finally, IED attacks have increasingly been in the
form of suicide bombings in which the insurgent or terrorist
is indistinguishable from the civilian population. This
allows the explosive device to be mobilized through public
spaces and detonated at the optimum opportunity to cause
maximal indiscriminate injury . The detonation of a sui-
cide bomb is meant to generate fear, chaos, and dramatize
the effect of the attack through targeting of busy restaurants
or nightclubs, crowded public transportation, military re-
cruiting stations, or open public spaces [30–33]. These sui-
cide bombs force change in everyday behavior and cause an
additional level of psychological and emotional damage on
the local population and coalition forces . Suicide
bombs have increased in lethality with the use of high-
grade military explosives, and as previously described, with
the addition of projectile material surrounding the casing to
intensify fragmentation injury.
Biophysics of blast trauma
Explosions produce complex and astonishing injury pat-
terns, with multisystem involvement including pulmonary
injury, traumatic brain injury, burns, amputations, crush
syndromes, and blunt or penetrating injuries to the viscera,
axial skeleton, and extremities . The behavior and char-
acteristics of these blast events have been difficult to pre-
dict and generalize because the variable severity and
spectrum of injury with each attack is largely related to
the explosive weight and material, as well as the prepara-
tion and detonation technique of the IED device. However,
an increasing understanding of the basic blast biophysics
and pathophysiological effects will allow better planning
and treatment of the consequences after IED attacks.
Explosive devices cause injury by multiple mechanisms,
some of which are exceedingly complex. The wide spec-
trum of explosion-related injuries are often collectively re-
ferred to as ‘‘blast injuries’’ and has disguised the fact that
most debilitating and lethal wounds are predominately
caused by penetrating fragments, not by blast overpressure
. Therefore, when discussing explosion-related injuries,
there must be a clear understanding of the four types of
blast injuries, which include: primary, secondary, tertiary,
and quaternary (Table 2) [1,19,22,27].
When an explosive device is detonated, the explosive
material undergoes a rapid exothermic chemical reaction.
This releases a significant amount of stored potential en-
ergy by transforming the explosive material from a liquid
or solid to a gas [22,24,34]. This highly compressed super-
heated gas, termed the detonation product, then rapidly
expands with a local pressure typically reaching 1.4 to
3 million psi and temperatures ranging from 2,000?C to
6,000?C . This gas expansion then instantaneously
compresses the surrounding ambient air, forming a blast
wave that propagates supersonically and radially from the
detonation site. The air is highly compressed at its leading
edge, termed the blast front, and is the principle factor
causing primary blast injury or what is commonly referred
to as ‘‘overpressure’’ injuries [35,36]. The blast front inter-
acts with the human body by causing a rapid change in
pressure at the moment of impact and transfers an impulse
of energy from the transmitting medium (air or water) to
the body surface [24,25]. As the blast wave and blast front
quickly dissipate, they are followed by the blast wind. The
Common explosive types and characteristics [1,20,21,23–25]
Explosive typeTNT equivalent ConsistencyCharacteristic
Used in Oklahoma City attack in 1995 (4,800 lbs TNT equivalent)
Highly volatile; used to make dynamite
Pipe bomb (5 lbs TNT)
155-mm artillery round (220 lbs TNT)
Car bomb (2,000 lbs TNT)
40% TNTþ60% RDX Composition B
Plastic91% RDXþ(rubber, oil, plasticizer); triggered by mechanical shock
wave resulting in rapid detonation (‘‘brisance’’)
TNT, trinitrotoluene; ANFO, ammonium nitrate/fuel oil; NG, nitroglycerin; RDX, cyclotrimethylenetrinitramine; PETN, pentaethyltrinitride; N/A, not
4 D.G. Kang et al. / The Spine Journal - (2012) -
blast wind is a region of high pressure, which travels slower
than the blast wave, propelling fragmentation, large objects,
and humans considerable distances and is the principle fac-
tor causing secondary and tertiary blast injuries [24,25,37].
Although termed secondary blast injury, this mechanism
continues to be the most common cause of injury and death
after an explosion [1,25,27,38]. The severity of injuries and
risk of death increase with a larger amount of explosive ma-
terial and at a closer distance to the explosion epicenter.
There has been an overemphasis on primary blast injury,
with only 3% to 5% of injuries after an explosion occurring
from primary blast injury, with most being tympanic mem-
brane ruptures . This is because an intense blast is nec-
essary to produce manifestations of primary blast injury
other than tympanic membrane rupture, and there is a rapid
decrease in peak overpressure with increased distance from
the explosion epicenter. Secondary blast injury is much
more common because fragments after an explosion can
travel long distances from the explosion epicenter with ini-
tial velocities up to 6,000 m/s. [19,32,39–43] At close
range, potentially survivable fragmentation injuries are
unlikely, and in an open space environment, the maximum
effective range for secondary blast injury exceeds primary
blast injury by a factor of 100 (Fig. 4) [1,24,44,45].
Although injury patterns after IED explosions are exceed-
ingly complex, in general, a casualty close enough to sus-
tain a significant primary blast injury will likely be killed
by fragmentation [1,24].
Blast biophysics of open versus closed space
There are many factors that influence blast trauma bio-
physics; however, the environment in which the explosion
takes place has a significant role and must be considered
. Although the current conflicts in Iraq and Afghanistan
Blast injury classification
ClassificationDescription Injury pattern
? ‘‘Overpressure’’ injury
? ‘‘Implosion’’ occurs at time of contact with body
surface, blast front rapidly compresses gas-filled
organs and then near instantaneously reexpands as
blast front passes
? ‘‘Spalling’’ occurs as blast front propagates through
body, significant shear and stress forces because of
differences in tissue density of adjacent organs and
tissue at air-fluid interfaces; causes forcible explosive
movement of fluid from more dense to less dense
? Auditory shift (2 psi)
? Tympanic membrane rupture (5 to 15 psi)
? Lung injury; pneumothorax; pneumomediastinum;
air embolism; intestinal emphysema (30 to 80 psi)
? 50% chance of death (130 to 180 psi)
? Probable death (200 to 250 psi)
? Gastrointestinal tract injury
? Tearing of organ pedicle
? Eye injury
? Penetrating injury
? Traumatic amputation
? Ballistic injury from primary bomb casing fragments;
also from secondary fragments (ie, environmental
material, metallic debris, glass); become projectile
after energized by explosion
? Fragments strike the body and cause penetrating
injuries; can also cause traumatic amputations
? Variable velocity depending on size/shape of
fragment and distance from explosion epicenter;
rapid deceleration because of aerodynamic drag
? ‘‘Shimmy’’ effect from irregularly shaped fragment
contacts body and exhibits tumbling; increases
amount of local tissue damage
? Whole body translocation
? Blast wave energizes and propels individual to
tumble along the ground or thrown through air to
strike hard surface
? Large object may become projectile and impact
individual causing significant blunt or crushing
? Crush injuries caused by structural damage and
? Blunt injury
? Crush injury
? Compartment syndrome
? All other explosion-related injuries
? Burn injury
? Toxic gas or smoke inhalation injury
TBI, traumatic brain injury.
5 D.G. Kang et al. / The Spine Journal - (2012) -
have predominately experienced open space environment
explosions, there are substantial different effects when an
explosion occurs within an enclosed space . In an open
space environment, the nearly instantaneous peak in ambi-
ent air pressure quickly decays as it travels away from the
explosion epicenter through a well-defined pressure/time
curve called a ‘‘Friedlander wave’’ [24,25] (Fig. 4). In an
enclosed space, this typical relationship does not occur,
as blast waves deflect, reflect, and coalesce, which can
magnify the destructive power eight to nine times and cause
significantly greater injury [25,28,40,46,47] (Fig. 5). As
a consequence, immediate death from primary blast injury
from pulmonary injury occurs more often in an enclosed
space explosion [28,46,47]. The increased energy of the
complex and reflected waves can also generate a larger
number of secondary fragments through destruction of the
building or vehicle, with an increased likelihood of tertiary
blast injury from structural collapse . During the 1995
Oklahoma City bombing, in the uncollapsed portion of the
building, 5% died and 18% of survivors were hospitalized,
whereas in the collapsed portion of the building, 87% died
and 82% of survivors were hospitalized [1,48]. In another
study, closed space bus bombings were found to reach mor-
tality of nearly 50%, whereas open space environment
bombings were associated with an 8% mortality [1,28].
Blast interaction with vehicles
There is a particularly complex sequence of injury mech-
anisms when an explosion occurs outside of an enclosed
space such as a building or vehicle. The occupants are pro-
tected to some extent from primary blast injury as the blast
wave diffracts around and reflects off the exterior of the
building or vehicle, with only a small portion transmitted
onstrated that the risk of overpressure injuries is substan-
tially reduced when inside a vehicle, with the peak
overpressure outside a vehicle approximately 28 times than
that inside the vehicle when a 17-kg explosive is detonated
3-m away . For example, after an IED attack, an individ-
ual inside a vehicle exposed to an overpressure of 5 psi may
result in tympanic membrane rupture, whereas a combatant
outside the vehicle and protected from fragment injury
would likely experience an overpressure of 150 psi, which
[1,37]. Although offering protection from primary blast in-
jury,there can still be significantinjuryif there isenough en-
ergy to cause fragmentation of building or vehicle material,
projectile glass from broken windows, or complete destruc-
placement and is particularly prone to vertical displacement
if a flat vehicle floor traps the detonation product and allows
for considerable pressure concentration and energy transfer
and may result in vertical acceleration and displacement of
the vehicle . This can also cause rupture of the vehicle
floor and endangers the occupants by exposing them to sec-
ondary fragmentation and superheated high-pressure gases
leading to quaternary blast injury (Fig. 6, Left). Therefore,
Fig. 4. Illustration of ‘‘Friedlander curve,’’ with maximum effective radius for primary and secondary blast injuries of an open-field 155-mm mortar shell
explosion with 200 lbs (100 kg) of trinitrotoluene equivalent; potential injury from fragmentation can exceed 1,800 ft [1,19,24,45]. Adapted from Champion
et al. .
Fig. 5. Illustration of blast wave magnification in an enclosed space.
6 D.G. Kang et al. / The Spine Journal - (2012) -
a more slender or V-shaped vehicle floor allows the detona-
tion product to flow and bend along the path of least resis-
tance and is released around the vehicle (Fig. 6, Right)
The development of a V-shaped hull sitting high on thevehi-
cle chassis dates back to World War II, with the first imple-
mentation in the Swedish Armored Personnel Carrier during
has a significant effect on acceleration and displacement of
the vehicle, with the most basic relationship demonstrating
acceleration to be inversely proportional to mass (accelera-
tion5force/mass) . Therefore, for the same explosion
intensity, a heavier vehicle with a V-shaped hull will experi-
ence decreased acceleration, peak velocity, and displace-
ment compared with lighter flat hull vehicle .
Tertiary blast injury is the most significant injury mech-
anisms for occupants in a vehicle after an IED attack and
can occur at several different times after the explosion
event. First, the forces causing vertical acceleration of the
vehicle can be transferred to the seated occupant causing
lower extremity, pelvis, and spinal column injuries. The oc-
cupant can then incur significant head and spinal column
injuries from striking the roof of the vehicle, as they are
thrown around inside or ejected from the vehicle; especially
with only limited seat belt use and availability and no air
bag restraint system available in military vehicles . After
reaching the peak of its force-dependent displacement, the
vehicle then accelerates back to the ground where the occu-
pants are again subjected to blunt- or crushing-type injuries
at impact . Finally, there can also be significant injury if
poorly stowed or inadequately restrained equipment be-
comes projectile and strikes the occupants .
Many of our combat casualties have occurred by IED at-
tacks on vehicle convoys, and there have been advances in
military vehicle designs to improve survivability after an ex-
plosion, and most recently with the developmentof the Mine
Resistant Ambush Protected armored vehicle. A number of
different strategies have been implemented to reduce the le-
thality and morbidity of the four different blast injury mech-
anisms. Increasing the distance between the epicenter of the
explosion and the crew compartment can reduce primary
creased height of the crew compartment. Improvements in
vehicle armor, blast deflectors, and personal protection to
prevent fragment penetration have reduced the secondary
blast injury. Tertiary blast injuries have been countered
through altering vehicle geometry and structure, increasing
vehicle mass, and blast deflectors to reduce energy transfer
vehiclestructureand in personal clothing,as well as separat-
Blast trauma has produced a wide pattern of combat in-
juries not commonly experienced in the civilian commu-
nity. Spine injuries after an IED blast are likely
multimechanistic, but most are caused by secondary and
tertiary blast injuries resulting in blunt- and crushing-type
injury patterns. We have experienced an unusual increase
in rare injury patterns, such as low lumbar burst fractures
and lumbosacral dissociation injuries, and although several
different mechanisms have been postulated, there is no con-
vincing evidence to date to further focus our research ef-
forts. Despite the significant impact of explosion-related
injuries on our deployed servicemembers, there has only
been limited literature concerning the epidemiology, treat-
ment, and outcomes of wartime spinal column and spinal
cord injuries [2,5,7,49,50]. In fact, most studies regarding
wartime-related spine injuries have focused on epidemiol-
ogy and wounding patterns, with only limited treatment
and outcomes-related data. However, as our understanding
of the epidemiology and patterns of injury continues to ex-
pand, we hope to further elucidate the optimal clinical treat-
ment algorithm based on patient outcomes and focus our
research efforts to prevent injury through personal or vehi-
cle protection design. Also, little is known about the long-
term consequences on spine health after exposure to blast
Fig. 6. Illustration of detonation product buildup and increased impulse under flat hull, with rupture of vehicle floor and occupants exposed to fragmentation
and superheated high-pressure gases (Left); detonation product flowing around V-shaped vehicle hull (Right) .
7 D.G. Kang et al. / The Spine Journal - (2012) -
trauma, particularly after multiple exposures in the absence
of obvious spine injury. While the treatment and immediate
consequences of the combat casualty with spine injury have
been the purview of military orthopaedic spine surgeons
and neurosurgeons, spine surgeons throughout the commu-
nity will be faced with a growing population of war vet-
erans who have been exposed to blast trauma and report
disability from back pain or previous spine injury. Also,
an understanding about the effects of blast trauma by all
spine physicians in the community has become imperative,
as the battlefield has been brought closer to home in many
countries through domestic terrorism and mass casualty sit-
uations, with the lines blurred between military and civilian
trauma [30–33,51–53]. We hope to have encouraged further
thought and innovation for spine injury prevention, pro-
voked future experiments, or investigations to improve
treatment of these complex spine injuries and stimulated
awareness of the possible consequences on spine health
after exposure to blast trauma.
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