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22 • Lower Extremity Vascular Trauma 275
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Patient and Limb Outcomes
The major outcomes of interest for lower extremity vascular
injuries are mortality and delayed amputation. In general,
limb salvage is the primary goal of the surgical management of vascular injuries to the leg. Vascular reconstruction
to salvage a limb should not take priority over interventions
to preserve life in the multiply injured patient. The surgeon
planning to perform a vascular reconstruction in a traumatically injured leg must understand the limb injury in
the context of the entire complex of traumatic injuries and
physiologic status of the patient in order to most effectively
plan the intervention and ensure the potential for the best
possible outcome for the limb and the patient. Both pre- and
intraoperative communication with the entire team caring
for the patient is vital to this understanding. Trauma and
orthopedic surgeons and anesthesiologists can provide signicant insight that is vital to planning a vascular reconstruction in the context of the patient’s overall condition
and potential for limb salvage.
Fig. 22.2 Massive, high-energy military lower extremity trauma. This
injury was caused by an improvised explosive device and primary
amputation was performed.
MORTALITY
In the injured patient, hemorrhage causes of about one-third
of deaths.
lower extremity vascular injuries, however, are very uncommon, even in the presence of a named arterial or venous
injury.
as an outcome in clinical series of vascular injuries to the
lower extremity and specic risk factors are not dened. The
recent, military inspired adoption of tourniquets as primary
hemostatic measures in the civilian prehospital arena may
serve to diminish mortality associated with vascular injuries
to the leg further.
level of vascular injury becomes more proximal, the mortality rate increases, ranging from around 1% with tibial
injuries to almost 8% at the common femoral level. Because
hemorrhage is the likely cause of mortality from a vascular
injury to the lower extremity, it stands to reason that disruptive injuries (primarily resulting from penetrating mechanisms) produce most of these fatalities.
18–20
Deaths resulting from hemorrhaging isolated
12,21
Because of this, mortality is infrequently reported
22–25
In isolated leg vascular injuries, as the
12,21
AMPUTATION
Limb salvage should be the primary goal of vascular intervention on the lower extremity in the setting of limb trauma
as long as the attempt does not threaten the patient’s life.
In military lower extremity vascular injury, primary amputation (dened as amputation without an attempt at limb
salvage) is predominantly performed in cases of massive tissue injury as a damage-control maneuver13 (Fig. 22.2). In
civilian trauma, secondary amputation (dened as amputation following an attempt at limb salvage) is the most
commonly reported outcome measure in clinical series of
lower extremity vascular injuries. Injury to the popliteal
artery consistently produces the highest amputation rates,
with the common femoral injury producing the lowest.26
Overall, amputation following blunt injury to the popliteal
artery is performed in up to 35% of patients; however, secondary amputation after attempted reconstruction has an
incidence of around 10%.
erally produce low rates of secondary amputation, unless
12,27–30
Tibial artery injuries gen-
multiple tibial arteries are injured, in which case the amputation rate can exceed 10%.
6,8,12,31
At any arterial level, limbs
injured via blunt mechanism are at higher risk of secondary amputation than are those having sustained penetrating trauma, likely due to the preponderance of associated
tissue injuries produced by blunt trauma.
6,8,12,26,28,31–33
The
mangled extremity severity score (MESS) was developed
as a clinical tool to predict amputation in civilian extremity trauma,
amputation in single-center reports.
34,35
and higher MESS has been associated with
6,8
A consistently predictive MESS cutoff score has been elusive, however, and
the efcacy of the scoring system itself has been called
into question.36 Published registry data also suggests that a
delay of greater than 60 minutes from the time of injury to
the time of an operation for revascularization is associated
with amputation in civilian trauma,32 though this is not
a consistent nding in single-center reports.
6,8
Prolonged
ischemia of greater than 6 hours, however, is a consistent
predictor of delayed amputation in military and civilian
vascular trauma.
7,13,26
The secondary amputation rate encountered following
military lower extremity vascular injury is strongly related
to the mechanism of limb injury. The high-energy blast
trauma that results in the large majority of modern military
vascular injuries is associated with much higher amputation rates than gunshot wounds, which comprise most
of the remaining injuries.
extremity vascular trauma, popliteal artery injuries carry
especially high amputation rates.
7,15,17,37
As with civilian lower
37,38
Secondary amputation following military injuries is associated with the severity of concomitant limb tissue injuries, especially in cases
where there has been signicant tissue destruction.
13,17
Various aspects of the presenting physiology of the patient
and characteristics of the limb injury complex have been
studied as potential risk factors for secondary amputation
in published civilian and military series’ including all lower
extremity arterial levels.
Table 22.2 presents a review of studies of civilian lower
extremity vascular injury and associated risk factors for
secondary amputation.
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Table 22.2 Studies of Civilian Lower Extremity Vascular Injury and Associated Risk Factors for Secondary Amputation
Author
Civilian Alarhayem
et al.
Liang et al. 2004–14 Trauma Center
Topal et al. 2002–09 Trauma Center
Perkins
et al.
Kauvar
et al.
Military Sisli et al. 2011–13 Syrian Conflict
Perkins
et al.
Thomas
et al.
Blank, not studied; X, found to be a risk factor; O, not found to be a risk factor; .JTTR, Joint Theater Trauma Registry; MESS; mangled extremity severity score; NTDB,
National Trauma Data Bank.
Time
Frame Source
2012–15 NTDB X O X X X X
(USA)
(Turkey)
1984–2008 Metaanalysis X O O X O X X O O
2002–06 NTDB X O O O X X X O O O
(Turkey)
2003–12 JTTR-Iraq/
Afghanistan
(USA)
2004–12 JTTR Iraq/
Afghanistan
(USA)
Blunt/
Blast Hypotension
X O X O X X X X
O X X X O X X X
X O X X O X
X X X X X X X X
X X X X O X X
Pulse
Deficit
Nerve
Injury Fracture
Popliteal
Injury
Multiple
Arterial
Injuries
Soft Tissue
Destruction MESS
Injury
Severity
Score
LIMB COMPLICATIONS
Complications other than amputation are infrequently
reported in both the civilian and military vascular trauma
literature. Limb complications may not develop during the
initial inpatient stay and may be underreported, especially
in data from civilian centers where loss to follow-up rates
are notoriously high. Complications of the reconstruction itself include thrombosis, stenosis, and anastomotic
or graft breakdown which can present as pseudoaneurysm, blowout, and arteriovenous stula. Saphenous vein
is the conduit of choice for the repair of lower extremity
vascular injuries, but even with the use of this conduit,
early (within 30 days) graft thrombosis is reported in 10%
or more of civilian lower extremity vascular reconstructions. The thrombosis risk is related to the location of the
distal target (and thus the robustness of the outow) of
the graft; grafts to the tibial vessels perform much more
poorly than those with more proximal targets.
thrombosis of a vascular reconstruction should be taken as
a sign that there is a problem either with the reconstruction itself or with the outow, and investigation (typically
re-exploration, thrombectomy, and angiography) should
be performed. If necessary, the reconstruction may require
revision or replacement to maximize the chance for limb
salvage. Despite these maneuvers, early graft failure is associated with a high limb loss rate.
37,39
Graft or anastomotic
stenosis is a late-developing complication that is essentially
unreported in the civilian literature. It is generally thought
that stenosis is less common in vascular trauma reconstructions than in those performed for chronic occlusive disease
because of the relative absence of atherosclerosis in the
typically young, healthy trauma patient. There is no good
quality evidence to support this supposition, however, nor
is there any indication that duplex ultrasound surveillance
of vein grafts placed for vascular trauma may facilitate
early identication of graft-threatening stenosis. The use of
39,40
Early
meticulous vascular surgical technique is the best way to
prevent stenosis or thrombosis of a vascular reconstruction.
Using the best available conduit (preferably single-segment
saphenous vein), constructing spatulated anastomoses free
of tension and torsion, and avoiding kinking or twisting of
the graft are all aspects of technique which minimize the
chance for a graft stenosis or thrombosis.
Breakdown of the anastomosis or of the graft itself (typically at the site of a saphenous tributary) occurs with about
half the frequency of graft thrombosis and presents with
potentially catastrophic hemorrhage.40 Like graft stenosis, these complications take time to develop and are likely
underreported from civilian centers. In military reports
with longer clinical follow-up periods, graft breakdown is
seen at a rate of approximately 6%, about twice that seen in
civilian trauma.
40–43
There is an association between anastomotic dehiscence and acute or chronic vascular graft
infections in nontrauma reconstructions which likely holds
in the trauma setting as well. Accordingly, any anastomotic
dehiscence or graft breakdown not directly attributable to
a technical error should be investigated and treated with a
high index of suspicion for infection.
Limb wound infection following vascular reconstruction in high-energy military blast trauma is another slowly
developing complication and is reported in up to 30% of
cases. Wound infections following civilian lower extremity vascular injury are reported in about 10% of cases and
are probably related to the magnitude of tissue injury and
contamination rather than the vascular injury or its treatment. In addition to infection, desiccation of a vascular
reconstruction can also lead to breakdown and potentially
signicant hemorrhage. In addition to employing the best
possible aseptic surgical technique, coverage of all exposed
vascular graft tissue, including complete coverage of all
anastomoses with healthy musculocutaneous tissue, is the
key to preventing desiccation and minimizing the chance of
infection.
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FUNCTIONAL OUTCOMES AND QUALITY OF LIFE
Patient-level outcomes such as extremity performance and
quality of life following lower extremity vascular injury
have been largely unreported, in part due to the noted difculty in attaining mid- and long-term clinical follow-up of
these patients. A discussion of the functional implications
of posttraumatic amputation is beyond the scope of this
chapter, but even following salvage of a severely injured
extremity, there may be signicant disability and quality of
life issues for both military and civilian patients.
44–46
Much
of the disability and dissatisfaction reported by patients following extremity vascular injury is due to the pain and loss
of physical performance caused by musculoskeletal and
nerve damage and not signicantly attributable to vascular insufciency. Blunt mechanism and limb injury severity
predict poor results on functional independence and quality of life scales in the few studies that have examined these
variables over the long-term in populations of patients following leg vascular injuries.
13,33,47
Functional outcomes specic to the vascular injury in
lower extremity trauma remain unstudied for the most part.
Applying the dogma of chronic vascular insufciency in the
setting of posttrauma outcomes, it would be expected that
failure of a femoropopliteal reconstruction would result in
exertional ischemia and intermittent claudication, whereas
failure of a more distal reconstruction would result in ischemic rest pain or in tissue loss. The pathophysiology of
atherosclerotic vascular insufciency and that of vascular trauma differ signicantly, however, as do the patient
populations. Without long-term follow-up data on trauma
patients to support the application of chronic disease principles to the outcomes of vascular reconstruction for injuries, we can only guess as to the nature and strength of any
association between the two disease processes. As we move
towards examining the true functional outcomes in chronic
lower extremity vascular insufciency, we should make an
effort to study these outcomes in the trauma population
as well.
48,49
Concomitant and Isolated
Vein Injury
Major lower extremity venous injuries are reported in combination with arterial injury in a quarter to a half of cases
of military and civilian limb trauma. Concomitant vein
injuries are most frequently seen accompanying SFA injury
(approximately 40%–60%), and are less common with common femoral and popliteal (10%–25%) and tibial (10%)
artery injuries.
injury is infrequently described and is likely underreported
as most attention is focused on the management and outcomes of arterial injuries. The reports that do exist of lower
extremity venous injuries have concomitant arterial injury
rates of 15% to 40%.
setting of a lower extremity arterial injury is a marker of a
more severe limb injury complex and an indicator of poor
limb salvage prognosis.
Major lower extremity venous injuries consist of vessel transections and lacerations that can present with
12,50
Isolated lower extremity major venous
51–54
Concomitant vein injury in the
signicant hemorrhage. The decision to ligate or reconstruct
such injuries, whether they occur in isolation or concomitant with arterial injury, remains controversial. Disrupted
single tibial veins can be safely ligated; however, ligation of
a major (femoropopliteal) lower extremity vein in the setting of limb trauma carries the theoretical risk of precipitating venous hypertension leading to distal tissue edema
and potentially compartment syndrome. However, venous
surgical repair in the trauma setting is technically demanding, time consuming, and is believed to have generally poor
patency in the low ow venous system.50 Both lateral venorrhaphy and venous interposition graft reconstructions are
unfavorable given that they disrupt endothelial continuity
and narrow the ow lumen, risking thrombosis. Early (7to 30-day) patency rates for lower extremity venous reconstructions performed for trauma are between 60% and 70%
in reports, and it is likely that this represents an overestimation of venous patency because occlusions may be clinically
52,54
silent.
If these are attempted, they have the best chance
for success if there is undisturbed distal venous inow (i.e.,
minimal distal soft tissue disruption) and preserved proximal venous outow. Major lower extremity venous ligation
is well accepted in cases in which the time needed to surgically reconstruct the vein injury is not available due to the
patient’s tenuous physiologic status or when the severity of
the overall injury complex makes the venous injury a low
priority.
Even with decades of retrospective data from clinical
studies, there is no consensus in the literature regarding the appropriate surgical management of major lower
extremity venous injuries. The theoretical physiological risks of major venous injuries are acknowledged, and
symptomatic leg edema is reported, but very few studies
published in the past decade describe an association with
venous ligation and limb loss. Secondary amputation rates
of approximately 5% to 10% following ligation of injured
femoropopliteal veins are reported in recent studies that
include concomitant arterial injuries, with much lower
rates following ligation of isolated venous injuries.
50,52,53,55
Ligation of a major lower extremity vein injury is also
thought to predispose the patient to the development of
venous thromboembolism (VTE). The VTE rate does appear
to be high in cases of lower extremity venous injury, ranging from 30% to 50% in studies.
50,51,56
However, the development of VTE does not appear to be associated with the
surgical management of major lower extremity venous
injuries. In fact, lower VTE rates have been reported with
ligation than repair in some studies.
50,54
Table 22.3 presents a brief review of published studies of
lower extremity venous injury outcomes.
Given the lack of consensus in the literature, our typical practice is to avoid routinely performing complex lower
extremity venous reconstructions for trauma. Operative
treatment is rarely required for isolated venous injuries in
hemodynamically stable patients and bleeding from larger
veins may be surgically controlled with direct suture or ligation with or without formal inow and outow control. We
generally reserve inline venous reconstruction for cases in
which outow compromise is demonstrated by early arterial
or shunt thrombosis, poor quality arterial signals following
reconstruction (after fasciotomy and conrmatory angiogram), or overt evidence of compromised venous outow
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Table 22.3 Studies of Lower Extremity Venous Injury
Author Year Cases Major Findings
Parry et al. 2003 86 treated femo-
Kurtoglu
et al.
Quan et al. 2008 82 combat venous
Manley
et al.
Matsumoto
et al.
CEAP, Clinical impact, Etiology, Anatomy and Pathophysiology (classification); DVT, deep vein thrombosis; NTDB, National Trauma Data Bank; PTFE,
polytetrafluoroethylene; VTE, venous thromboembolism.
2007 63 ligated
2017 94 isolated venous
2019 2120 NTDB
ropopliteal vein
injuries
iliofemoral and
popliteal vein
injuries
injuries
injuries
venous injuries
(includes tibial)
No difference in amputa-
tion rate between
ligation and repair
No difference in patency
between venorrhaphy,
interposition with
autologous vein or PTFE
89% postoperative edema
59% DVT <5 days
15 of 25 with follow-up
CEAP C2 or C3
No difference in VTE,
phlegmasia, or fasciotomy rate between
ligation and repair
22% vein repair
thrombosis
No difference in amputa-
tion rate between
ligation and repair
VTE more common with
repair
Ligation a weak indepen-
dent predictor of amputation and fasciotomy
with early massive venous bleeding or tissue edema. The
most common lower extremity locations to require venous
reconstruction are the popliteal segment (especially above
the knee) and the femoral conuence. Signicant loss of
antegrade venous drainage at either of these levels generally produces signicant distal venous congestion.
Venous reconstructions usually require distal thrombectomy. It can be difcult to pass an embolectomy catheter distally, and we therefore favor Esmarch thrombectomy from
the foot to the surgical site to deliver any thrombus and conrm patent venous inow. Inline venous reconstructions
can consist of simple suture repair, lateral venorrhaphy,
or short interposition grafts. Long venous bypasses do not
have good patency when performed in the elective setting,
and we do not recommend them for use in the setting of
acute trauma. Autologous conduits are preferred, but largediameter expanded polytetrauoroethylene (ePTFE) grafts
have been reported to have similar short-term patency.
52
Presentation, Diagnosis, and
Workup
The characteristics of an extremity injury’s early presentation are key factors in determining the urgency of the clinical workup and the nature of necessary initial interventions.
The traditional workup for lower extremity vascular injuries
has been based on the presence or absence of hard and soft
signs of vascular injury. Hard signs are reported to provide
denitive evidence for the presence of an arterial injury and
Table 22.4 Hemorrhagic and Ischemic Signs of
Extremity Arterial Injury
Hemorrhagic Signs Ischemic Signs
Active hemorrhage (especially
pulsatile) from a limb wound
History of large volume of limb
hemorrhage
Systemic hypotension not
accounted for by other injuries
Pulsatile mass in proximity to
suspected area of injury
Palpable thrill in proximity to
suspected area of injury
Hematoma (especially expanding)
or limb circumference
discrepancy
Diminished or absent distal
pulse
Ankle-brachial index <1.0
Cool limb distal to suspected
injury
Pallor distal to suspected injury
Impaired motor or sensory func-
tion distal to suspected injury
include absence of distal pulse, active pulsatile bleeding,
palpable thrill or audible bruit, and expanding hematoma.
Soft signs suggest an arterial injury and include diminished
distal pulses, reported history of signicant bleeding, neurologic decit, and proximity of a wound to a named vessel. These signs were developed primarily for the evaluation
of patients with penetrating limb trauma and are intended
to drive the decision of whether to take a patient directly
to the operating room for surgical exploration (in the presence of hard signs) or to pursue vascular-specic imaging
(with soft signs). The data validating hard and soft signs of
vascular injury is now over 30 years old and was produced
long before the adoption of routine CT angiography (CTA)
imaging for nearly all trauma patients. Given this and that
the vast majority of trauma occurs via a blunt mechanism,
the traditionally applied distinction between hard and soft
presenting extremity signs is not particularly useful in the
modern trauma workup.
A more relevant and modern distinction can be made
between hemorrhagic and ischemic presenting signs of
extremity vascular injury. These are better suited to guide
the initial workup and management plan for an extremity
with suspicion of a vascular injury and broaden the scope
of initial suspicion for an injury to prevent missed injuries
(Table 22.4). These signs are operationally relevant in that
they not only suggest the presence of a vascular injury, but
also inform the initial management of an injured extremity.
Hemorrhagic signs tend to result from penetrating trauma
and typically represent localized vascular injury. The presence of a hemorrhagic sign may be evidence of a potentially life-threatening major arterial injury requiring urgent
intervention. Such injuries may require urgent temporary
hemostasis measures such as the application and maintenance of direct manual pressure, placement of a tourniquet
or, potentially, placement of an infrarenal occlusion balloon,
especially if they are accompanied by systemic hypotension
and/or shock. In these cases, urgent temporary bedside
hemostasis should be followed by a rapid clinical evaluation
of the anatomy of the injury including an assessment of
the most feasible locations to achieve vascular inow and
outow control. Many urgent hemostasis measures alter or
cease ow to and through the zone of injury, making vascular-specic imaging problematic for identifying the anatomy of a vascular injury. Urgent operative exploration with
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expeditious vascular control is indicated when such measures make quality vascular imaging impossible. However,
if the patient can be stabilized and extremity hemorrhage
controlled without disrupting overall limb arterial ow, we
recommend preprocedural vascular imaging evaluation to
identify at least the extent of the vascular lesion and the
inow and outow vessels for operative planning in limbs
with hemorrhagic signs. Good quality CTA imaging is readily and rapidly available in most trauma departments and
provides a wealth of vascular and associated tissue information, making it our rst choice for the imaging of limbs
with suspicion of lower extremity vascular injury.
57,58
Limbs presenting with ischemic signs tend to have sustained blunt injury and their vascular pathology can be
expected to be more extensive than that seen in limbs with
hemorrhagic signs. One would also expect there to be a
greater degree of associated bony and soft tissue injury in
the face of ischemic signs. Bony injury can often be helpful in localizing the level of vascular injury in blunt limb
trauma. An unstable knee dislocation suggests an injury to
the popliteal segment directly behind the knee, whereas a
tibial plateau fracture will may be associated with an injury
to the distal popliteal artery or tibioperoneal trunk. These
injuries can therefore be more complex to reconstruct than
hemorrhagic injuries, but because of the absence of lifethreatening hemorrhage, the clinician has more time to
investigate their anatomy and plan reconstruction. Intervention planning for limbs presenting with ischemic signs
benets signicantly from CTA imaging for the reasons
mentioned previously. Ischemic vascular injuries tend to
require longer and more complex reconstructions occurring in the context of signicant nonvascular tissue injuries
that may require concomitant, prior, or subsequent surgical
repair. In such cases, the additional information provided by
a good quality CTA is invaluable for multidisciplinary surgical planning. In ischemic extremity vascular injuries, it is
important to determine a reasonable estimate of the length
of time the limb has been ischemic because this may inuence the operative sequencing and the use of damage control techniques such as shunting (discussed in Chapter 23)
as well as dening the potential risk for reperfusion injury
and the need for fasciotomy.
In any limb with hemorrhagic or ischemic signs of vascular injury, whether guided by preprocedural imaging or not,
one should go to the operating room with a basic plan for
the revascularization. This plan should be communicated
to the entire multidisciplinary trauma care team and at a
minimum should include the items presented in Table 22.5.
Technical Aspects of Vascular
Reconstruction
GENERAL CONSIDERATIONS
The initial procedure in the surgical management of lower
extremity vascular trauma is achieving proximal vascular
control. In a limb without active hemorrhage (ischemic
signs), vascular exposure for proximal control should occur
in an area that is generally free from tissue injury to ensure
that the inow source can be assessed fully through a standard vascular approach and to avoid potential disruption of
Table 22.5 Operative Planning Considerations for
Extremity Vascular Injury
Sequencing 1. Consideration of temporary shunting
2. Temporary fracture reduction
3. Vascular reconstruction
4. Fasciotomy
Technique Equipment availability and limitations
Inflow and outflow
exposures
Conduit choice Surgical prep and drape
Tissue coverage Local flap
(radiolucent table)
Incision placement
Clamp requirements
Wound category
Negative pressure dressing
tamponade at the injury site. In cases with active hemorrhage (hemorrhagic signs), a proximally placed tourniquet
or direct manual pressure should be applied for temporary
hemorrhage control and proximal vascular exposure and
control performed remotely. Once proximal exposure and
control are achieved, the focus should then turn to distal
vascular exposure. We favor distal exposure in an area that
is outside of the zone of tissue injury if feasible. This is of
particular value in cases with hemorrhagic presentations,
as active bleeding can be remotely controlled and the injury
more fully assessed. Once both proximal and distal circumferential vascular control are achieved, direct exposure of
the zone of injury can commence.
The vascular injury itself should be circumferentially dissected and fully explored. Mechanism of injury is a signicant consideration as extended ballistic tissue effects may not
be fully appreciated in the local exposure and more extensive
dissection may be required to fully evaluate the vascular
injury in high-energy injuries. The evaluation should note
the overall appearance of the vessel and degree of external mural disruption. The injured vessel should be opened
(typically longitudinally) to evaluate the type and degree
of intimal injury with care taken in penetrating injuries to
examine for the presence of disruption of the deep wall of
the vessel. Primary luminal repair for noniatrogenic injuries is not the best option for reconstruction in most cases.
It is often tempting to “tack down” a seemingly focal intimal
injury, but this can lead to short- or long-term failure.
Direct exploration offers the opportunity to select appropriate sites for inow and outow that will fully exclude the
injury. In general, shorter reconstructions are preferred due
to their better patency. The inow source should be inline
and free of proximal obstruction and the outow should
be inline to a patent named vessel. Once these are established, the quality of proximal pressure and backbleeding
should be assessed. If either is poor or absent, an attempt
at balloon-catheter thrombectomy should be made. If no
thrombus is returned and inow or outow remain compromised, further direct exposure and exploration may be
needed, especially in cases of inadequate inow. An on-table
angiogram may be considered to evaluate for a more proximal vascular lesion. A lack of backbleeding in the absence
of thrombus does not necessarily denote the absence of
adequate outow, especially in cases of severe injury with
long ischemic times or large amounts of hemorrhage. To
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evaluate for outow patency in the circumstance, distal
limb compression should elicit some degree of backbleeding
and is a reassuring nding.
In cases of severe (usually blunt) limb trauma with large
degrees of tissue disruption, we generally recommend placement of a temporary vascular shunt when anatomically
feasible, even for relatively short planned ischemic times.
Temporary shunting of a lower extremity arterial injury
provides two benets: it facilitates evaluation of the expected
result of vascular reconstruction—presence of a reasonable
distal Doppler signal conrms adequate inow and outow—and it allows for perfusion during vein harvest and/
or orthopedic manipulation. Once an arterial shunt is in
place, the distal limb should be examined. In the presence of
concomitant venous injury, we consider leaving our arterial
shunt in place for 15 to 20 minutes while vein is harvested.
Shunt thrombosis or development of a water hammer Doppler signal in the shunt should prompt consideration of outow obstruction or poor venous return requiring venous
reconstruction. Arterial shunting will also precipitate
venous outow in the zone of injury and can be used to identify veins requiring ligation or reconstruction to preserve
limb outow. Specic shunts are discussed in detail elsewhere in Chapter 23, but in lower extremity trauma, each
device offers different advantages. Thin tube shunts (Argyle)
are easy to place and secure and can be placed entirely inside
the artery. They are generally short, and extension into normal vascular tissue is required both proximally and distally,
potentially crossing branches placing them at risk of thrombosis. Longer exible shunts with bulb tips (Sundt) require
securing close to the injury and therefore do not have long
purchase lengths; however, they can bridge long distances,
and do not typically cross branch points, which may allow
for greater limb manipulation while they are in place.
Once shunts are in place, a multidisciplinary discussion
should occur if bony injuries are present. It is generally preferable to have the orthopedic team return the limb to length
so that an accurate distance to be bridged by the vascular
reconstruction can be determined. If both the proximal and
distal arterial segments will be easily accessed following
xation, it is reasonable to proceed with temporary or permanent orthopedic manipulation with the shunt in place.
It has been our experience, however, that xation spanning
the knee joint often impairs exposure of the popliteal segments, which are almost always more accessible with the
leg bent and a bump placed under the distal thigh. In these
cases, we favor performing the proximal anastomosis, then
bringing the leg to length and measuring conduit distance.
In reconstructions spanning the knee, we recommended
an additional centimeter of redundancy in the vein graft
to allow for exion without anastomotic tension. The distal
reconstruction is performed, followed by temporary or permanent orthopedic xation. Regardless of the sequencing
of the orthopedic and vascular limb procedures, it is critical to assess the physical status and patency of the vascular
reconstruction following limb elongation and xation.
CONDUIT, TUNNELING, TWISTING, AND
MEASURING
An autogenous conduit of greater saphenous vein (GSV) is
the typical and most versatile choice for use as an arterial
conduit in lower extremity trauma. Traditionally, the contralateral leg has been preferred; however, in cases where
no ipsilateral venous injury is present, the use of ipsilateral vein is reasonable and does not appear to be associated
with a higher complication rate than the use of contralateral vein.
39,59
One advantage of harvesting contralateral
saphenous vein is that if multiple surgeons are available, it
can often be harvested simultaneously with arterial exposure and preparation. If a conduit of greater diameter is
required, the internal jugular vein can be used. This vessel lacks length, however, and saphenous vein is preferred
and nearly always suitable for lower extremity reconstructions. We generally avoid using femoral vein in the setting
of major lower extremity injury.
In lower extremity trauma, tunneling is most often performed from above to below the knee. For femoral artery
injuries, an interposition can usually be performed directly
within the exposure site and short tibial to tibial artery
bypasses are rare. A wide variety of tunnelers are available,
but our preference is to use a device employing a cylindrical tube that remains in place during graft tunneling and
is removed over the graft, protecting it from twisting and
trauma. If a tunneler is not available, a long vascular clamp
can be used to pull the graft through the tunnel, but this
risks graft injury. It is critical that above-to-below-the-knee
tunnels are made in the plane between the femoral and tibial condyles to prevent graft kinking. Blunt nger dissection
should be used proximally and distally to guide the tunnel
into the appropriate plane.
Twisting of the conduit can result in early graft failure.
We recommend two techniques for avoiding this. Creation
of a single, continuous longitudinal mark on the vein graft
is a common practice and is advisable. There has been some
recent debate about the potential for alcohol containing
marker ink to cause vein damage, but we believe that the
benets of marking outweigh the likely small risk of this.
The marking should be made with the vein graft pressurized and should be placed along the vein such that it can
be visualized for both the proximal and distal anastomosis.
Care should be taken to remember that distal rotational
graft orientation might not be the same as proximal. The
second recommendation is to allow arterial pressurization
of the graft following the proximal anastomosis, which will
generally untwist it prior to orienting for the distal anastomosis. Care should be taken to not hold the graft during
pressurization as it can prevent untwisting. Pulsatile arterial ow should be clearly visualized through the graft or a
problem with inow or the graft itself should be suspected.
The most important aspect of graft length measurement
is harvesting adequate vein for creation of a conduit. Following harvest, the vein graft will shorten until it is pressurized; therefore, length measurements should be performed
with the vein in situ. An external measurement with suture
can be used to determine the needed graft length—this
measurement will be longer than the distance spanning
the proximal and distal anastomoses and will usually
ensure that adequate vein is harvested. Measurements
should account for the likely necessary excision of proximal and distal graft ends and for distance lost to spatulation. The GSV can generally be spatulated and/or dilated to
accommodate the diameter necessary for any needed lower
extremity bypass procedure.
22 • Lower Extremity Vascular Trauma 281
ry
y
emoral a.
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TECHNIQUES FOR ANASTOMOSIS
If the patient cannot be systemically anticoagulated with
heparin, local administration of heparin (10–100 units/mL)
by direct vascular injection through the anastomotic arteriotomy is advisable to prevent vessel thrombosis during clamping. When interposition or bypass grafting is required, we
recommend large spatulated anastomoses on both the proximal and distal ends. For most vessels, 2 cm of spatulation will
be adequate to ensure effective ow through the graft. The
native vascular tissue used for the anastomosis should be free
of injury and we recommend avoiding complete arterial transection leaving a bridge of arterial wall posteriorly if possible.
This prevents vessel retraction and is most important when
performing an interposition graft. With an intact posterior
strip of arterial wall remaining, the proximal and distal anastomoses can be measured and completed. Then the remaining tissue bridge can be lysed if desired (this maneuver is most
useful for brachial artery reconstruction, but is also helpful
for SFA interpositions). Standard running sutures of monolament polypropylene are almost always most appropriate,
and care should be taken to avoid narrowing at the heel and
the toe of the anastomosis. The “parachute” technique is
often required to adequately visualize the initial heel and toe
sutures placed for popliteal anastomoses, as these typically lie
deep within the surgical bed. This technique consists of placement of the rst few sutures without pulling the stitch taut
such that both the arteriotomy and graft can be easily seen.
Once sufcient sutures have been placed so that the remaining sutures will comprise the midportion of the anastomosis,
the sutures can be pulled taut and the graft brought in to
meet the arteriotomy. Just prior to completing the distal anastomosis, the graft should be forward bled and backbleeding
permitted to ush the reconstruction of all air and debris. In
the absence of atherosclerotic disease, once the reconstruction is complete and ow is permitted through the graft, a
palpable pulse should be present in the distal outow vessel.
In some cases, this may not be the case until fasciotomies are
performed. If a pulse is not present, on-table angiography can
be performed to conrm restoration of distal ow, as signicant vasospasm can occur in otherwise healthy vessels.
INJURIES TO NAMED VESSELS
Common Femoral Artery
Injury to the common femoral artery (CFA) is most frequently caused by penetrating inguinal trauma but blunt
injuries have been reported. Proximal exposure for vascular
control may require a retroperitoneal approach (Fig. 22.3),
which is especially helpful in hemorrhagic cases in which
direct pressure is being applied to the femoral artery or a
proximal thigh tourniquet is in place. The inguinal incision
should be made longitudinally and the inguinal ligament
identied and cleared overlying the inguinal canal. The vessels lie just beneath the ligament and, if proximal extension
is necessary, bers of the inguinal ligament can be divided
to facilitate proximal tissue retraction to access the distal
external iliac artery. Care should be taken here to avoid
injury to a circumex iliac vein coursing over the distal iliac
artery. This vein can be ligated and divided if necessary. A
schematic representation of the anatomy of the arteries of
the pelvis, groin, and thigh is presented in Fig. 22.4.
Reflected
peritoneal cavity
Fig. 22.3 Extraperitoneal approach to iliac vessels for control of junctional groin hemorrhage.
Ext. iliac a.
Deep iliac
Superf. iliac
circumflex a.
Superf.
epigastric a.
Ascend. branch lat.
circumflex a.
Transverse branch lat.
circumflex femoral a.
Lat. circumflex
femoral a.
Descend. branch lat.
circumflex femoral a.
Perforating branches
deep femoral a.
Lat. sup. genicular a.
Fig. 22.4 Surgical anatomy of femoral vessels.
Aorta
Common iliac arte
External iliac arter
Right
common iliac a.
Int. iliac a.
Superior
gluteal a.
Inf. gluteal a.
Common
femoral a.
Obturator a.
Medial circumflex
femoral a.
Superf.
femoral a.
Deep f
Descend.
genicular a.
282 SECTION 4 • The Management of Vascular Trauma
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Fig. 22.5 Stab wound to the common femoral artery (A). The superficial (B) and deep (C) femoral arteries are also circumferentially dissected
and controlled. The stab wound on the anterior surface of the common
femoral artery
thickness injury.
(arrow)
was accompanied by a smaller, posterior, full-
Once the CFA is controlled and circumferentially dissected, longitudinal arteriotomy and luminal exploration
are performed. Small defects may be repaired using patch
angioplasty with autologous vein or a bioprosthetic patch
(Fig. 22.5). This is most suitable in cases of iatrogenic CFA
injury from percutaneous access attempts. Due to the short
length of the vessel, patch repair is typically not sufcient
to reconstruct a CFA injured via a high-energy mechanism.
For contaminated wounds, autogenous CFA reconstruction
is preferred. GSV is the conduit of choice but if it is too small,
the internal or external jugular vein can offer a larger diameter conduit. However, this is rarely necessary over time a
GSV placed in the CFA position will dilate to accommodate
the CFA diameter.
The CFA is a short vessel, and as a result, inguinal vascular injuries often involve the supercial and/or deep
(profunda) femoral arteries (SFA and PFA). Even in cases in
which the SFA or PFA are not directly involved, these vessels
may require exploration to rule out injury and achieve distal vascular control. It is usually easiest to dissect the femoral bifurcation from proximal (at the inguinal ligament) to
distal. The caliber change from the CFA to the SFA is easily visible and is a good landmark for the location of the
deeply positioned PFA origin. A Potts vessel loop around the
PFA trunk is often helpful to control this vessel and, when
tightened, can serve to stabilize the femoral bifurcation to
facilitate reconstruction. If the PFA trunk is too short for
vessel loop control, a profunda clamp can be used to control the trunk and rst 1 to 2 branches. Individual control
of PFA branches is not typically necessary to treat femoral
bifurcation injuries. In femoral bifurcation reconstructions
we prefer performing an end-to-end anastomosis from the
CFA (or distal external iliac artery) to the PFA rst. This
allows for the best visualization of the deeply positioned
PFA reconstruction. Following this, a separate bypass can
be done from the PFA bypass (end-to-side) to the SFA (endto-end). If suitable autologous conduit is not available for
this reconstruction, an 8-mm prosthetic graft can be used
for the PFA bypass and a 6- or 8-mm for the SFA.
Superficial Femoral Artery
Treatment of an SFA injury in a patient with otherwise
healthy vessels is usually straightforward. For most of its
course through the thigh, the SFA can be simply exposed
via a longitudinal incision with anterior mobilization of the
overlying sartorius muscle. The most frequently-made exposure error is to make the incision too far posteriorly, overlying
the adductor longus or magnus muscle. Keeping the incision
at the level of the femur can help to avoid this. It is generally
unwise to attempt extensive mobilization and primary endto-end anastomosis of the SFA. Short distance end-to-end
interposition grafting with GSV is ideal for most SFA injuries. For more extensive SFA injuries, a formal bypass may
be necessary. In the setting of otherwise healthy vessels, we
recommend choosing the most distal portion of uninjured
artery to serve as the inow vessel. The distal target for SFA
reconstruction should be the most proximal uninjured portion of uninjured vessel with inline ow to the foot.
Isolated Profunda Femoris Injuries
In contrast to the CFA and SFA, the PFA is a thin-walled vessel with a variable branching pattern. Isolated injuries to the
PFA typically result from penetrating trauma and can manifest with overt external hemorrhage or thigh hematoma, or
as occult arteriovenous stula or pseudoaneurysm seen on
CT imaging (Fig. 22.6). Occult distal PFA injuries may present
in a delayed fashion and can be diagnosed with duplex ultrasound. Isolated proximal PFA injuries can be reconstructed
via standard techniques, most frequently interposition grafting (Fig. 22.7). Open surgical exposure and reconstruction
become challenging as the profunda and its branches course
deeper in the thigh (see Fig. 22.4). For these distal injuries,
we favor endovascular intervention with embolization via
an antegrade approach from contralateral CFA access. We
recommend mechanical coil embolization over chemical
foam or gel treatment as it preserves distal collateral perfusion and effectively depressurizes the area of injury.
Popliteal Artery
For practical purposes the popliteal artery has three segments: above, behind, and below the knee. Penetrating
injury can impact any popliteal segment, whereas blunt
trauma typically results in behind- or below-knee popliteal injury. A schematic representation of the anatomy
of the popliteal artery is presented in Fig. 22.8. The true
injury area is challenging to identify on imaging as injury
to the popliteal artery in the proximal or middle segment
often results in dissection aps that can extent distally. In
cases of popliteal vascular injury, preoperative CTA imaging offers a wealth of information regarding distal collateral
ow, the extent and level of bony injuries, and evidence of
pseudoaneurysm, arteriovenous stula, or extravasation in
22 • Lower Extremity Vascular Trauma 283
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Fig. 22.6 CT angiogram of an acute left profunda femoris artery pseudoaneurysm (
evidenced by layering arterial phase contrast within the femoral vein
(
arrow, bottom panel
Fig. 22.7 Delayed presentation of a pseudoaneurysm of the profunda
femoris artery following military blast fragment injury to the right
inguinal region. The pseudoaneurysm orifice (
panel
(
bottom panel
arrow, top panel
) was resected and excluded with a saphenous interposition graft
).
). An arteriovenous fistula is also present,
).
forceps, upper right
branch
lat. circumflex
femoral a.
Popliteal a.
Superior lat.
genicular a.
Inf. lat. genicular a.
Ant. tibial
recurrent a.
Ant. tibial a.
Fig. 22.8 Surgical anatomy of popliteal vessels including bony
landmarks.
Femoral a.
Descend.
genicular a.
Articular branches
descend. genicular a.
Superior medial
genicular a.
Inf. medial
genicular a.
Post. tibial a.
the surgically inaccessible behind-knee segment (Fig. 22.9).
On imaging, the popliteal artery from (just proximal to) the
top to (just distal to) the bottom of the patella is surgically
inaccessible from the medial approach without complete
lysis of the medial knee ligaments (essentially a disarticulation). This maneuver is highly morbid and is rarely necessary except in cases of severe ongoing popliteal hemorrhage
following proximal and distal anatomic vascular control.
Most injuries to the behind the knee popliteal segment can
be treated with planned exclusion from arterial ow after
reconstruction from above to below the knee.
Proximal popliteal exposure can be obtained as the SFA
exits the adductor canal or slightly higher or lower as needed.
This area provides generally predictable anatomy and a relatively supercial vessel location. Distal popliteal exposure is
somewhat more challenging, requiring a longitudinal incision 1 to 2 ngerbreadths medial to the medial border of the
tibia, blunt posterior mobilization of the medial head of the
gastrocnemius, and opening of the deep posterior compartment by dividing the attachments of the proximal soleus
muscle to the tibia. Fig. 22.10 depicts above- and below-knee
approaches. The tibial nerve is sizable in this location and is
a good palpable landmark for the popliteal vasculature. This
exposure can be extended distally to the origin of the anterior
tibial artery (ATA; running laterally away from the surgeon)
and further to expose the tibioperoneal trunk (TPT) and posterior tibial artery (PTA). This is important as blunt popliteal
injuries can cause signicant intimal disruption that may
extend distally. Ligation and division of the anterior tibial
vein facilitates exposure of the TPT. We recommend initial
preservation of this vein, with division if bypass to the TPT is
required. Even in thin patients, the popliteal artery lies fairly
deep in the wound in standard popliteal exposures. Deep cerebellar or Henley retractors can be seated on one side against
the femur or tibia and facilitate mobilization of the overlying
soft tissues. Potts vessel loops can be used for arterial control and, when tightened, will serve to bring the artery more
supercially, facilitating an easier anastomosis and avoiding
large metal clamps impinging on the small operative eld.
284 SECTION 4 • The Management of Vascular Trauma
Soleus
(par
Gastrocnemius
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Rectus femoris
Vastus medialis
Adductor longus
Sartorius
Saphenous nerve
Venae comitantes
Popliteal artery
Popliteal vein
Sartorius
Gracilis
Fig. 22.9 CT angiogram of a blunt injury to the left popliteal area with
arterial injury and arteriovenous fistula.
(arrow)
has arterial contrast opacification, as does the adjacent popliteal vein. There is a large pseudoaneurysm with hematoma in the popliteal fossa.
occludes just above the knee joint. The popliteal vein (anterior) and
pseudoaneurysm (posterior) also fill with arterial phase contrast.
Bottom panel: the
popliteal artery
Top panel: the
(wide arrow)
popliteal artery
abruptly
Reconstructions limited to the above- or below-knee popliteal segments for trauma are rare. An above-to-below-knee
bypass is most commonly performed. Proximally, both endto-end and end-to-side anastomoses are reasonable. If large
geniculate vessels are identied proximally, we favor and an
end-to-side proximal anastomosis with ligation of the popliteal artery distal to them to preserve collateral ow. The
above-to-below-knee tunnel must be created between the
femoral and tibial condyles and typically results in a bypass
length that is shorter than expected, but some redundancy
should be retained in the graft to accommodate knee exion.
Distal popliteal anastomoses can also be performed end-toside or end-to-end. In the end-to-side conguration, we favor
ligation of the native popliteal proximal to the anastomosis
to prevent continued pressurization of the excluded popliteal
segment. Tibial plateau fractures are high-energy injuries
and those with any degree of posterior displacement should
prompt concern for distal popliteal and/or TPT injury. If
tially divided)
Fig. 22.10 Above- and below-knee exposure of the popliteal artery.
Popliteal artery
Anterior tibial artery
Popliteal vein
Posterior tibial artery
Peroneal artery
there is concern for injury to the TPT, we recommend exposure of the PTA for use as a distal target for reconstruction.
The anatomic location of the PTA allows for creation of a
relatively straight tunnel and reconstruction. A bypass to the
PTA can ll the ATA and PTA through retrograde TPT ow.
Tibial Arteries
Injuries to the tibial arteries are encountered in the setting of severe lower extremity injury, especially in the presence of complex open tibial fractures (Gustillo IIIB/C).60 A
detailed physical examination is required in these cases and
preoperative CTA imaging can provide a good assessment
of the uninjured arterial supply to the foot. If CTA cannot
provide the requisite detail, then conventional angiography can be helpful. Traditional dogma is that a single patent vessel to the foot (with a palpable pedal pulse and/or an
ankle-brachial index of 1.0 or greater) is adequate for limb
salvage. If motor and sensory function is intact and there is
at least one vessel to the foot, operative reconstruction may
not offer an acute limb salvage benet, especially in the face
of signicant bony and soft tissue injury that may inuence the decision to amputate.
31,40
Single tibial artery injuries presenting with hemorrhage may generally be safely
treated with ligation. We recommend temporary occlusion
and assessment of distal perfusion (possibly with angiography) prior to formal surgical ligation.
In severely injured lower extremities with complex injury
patterns, the number of patent runoff vessels does seem to
correlate inversely with the risk of amputation, but given
the wide anatomic distribution of the tibial vasculature,
this likely represents the severity of the vascular injury
as a surrogate for the magnitude of limb tissue injury
31,60
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