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Soft Tissue Reconstruction
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oftheLower Limb
MahmoudKazemNassar, DanielJ.Jordan,
andSandipHindocha
35
35.1 Introduction
This chapter aims to review current and past
thoughts on reconstruction of the lower limb, discussing in particular the options in terms of soft
tissue coverage. This chapter does not aim to
review the emergency management of open fractures, or the therapy alternatives to chronic
wounds or malignancies of the lower limb, but
purely assesses the requirements that should be
reviewed on reconstructing a defect of the lower
limb. However, this end point needs to be taken
into account at the initial evaluation or presentation of the individual as it may spare the patient,
and surgeon, multiple procedures and considerable frustration.
A summary of ap options is considered, with
literature support, in regard to donor and recipient region, particularly as ap coverage is
regarded as the cornerstone of soft tissue coverage of the lower limb.
M. K. Nassar · D. J. Jordan
Plastic Surgery and Reconstruction Department,
Ninewells Hospital and Medical School,
Tayside NHS Trust, Dundee, UK
e-mail: mnassar@nhs.net;
D.jordan1@nhs.net
S. Hindocha (*)
Plastic Surgery & Laser Centre, Bedford Hospital
NHS Trust, Bedford, UK
35.2 The Lower Limb
The lower extremities of the human body are
more commonly known as the human legs, incorporating the foot, the lower or anatomical leg, the
thigh, and the hip or gluteal region.
The human lower limb plays a simpler role than
that of the upper limb. Whereas the arm allows
interaction with the immediate surroundings, the
legs’ primary goals are support and to allow
upright ambulation. Essentially, this means that
reconstruction of the leg is less complex than that
required in restoring functionality of the upper
limb. In terms of reconstruction, the primary goals
are based on the preservation of life and limb and
the restoration of form and function.
The leg consists of four main regions before
attaching to the pelvis. Working proximally, these
are the following: the foot, the lower or anatomical leg (from the ankle to knee), the thigh (knee
to hip), and the hip or gluteal region. Primarily,
the four areas work together to aid balance and
support, which, in turn, allow a human to stand
and walk.
Evolution has forced the lower limb to gain this
distinct feature, and although bipedal gait is not
unique to humans, an efcient upright locomotion
for long durations is. This adaptation has forced
the human leg to become longer and more powerful in comparison with our primate relations, as
well as change the way in which the muscles and
joints of the leg interact and function [1].
© Springer Nature Switzerland AG 2019
D. Duscher, M. A. Shiffman (eds.), Regenerative Medicine and Plastic Surgery,
https://doi.org/10.1007/978-3-030-19958-6_35
429
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The ability of the legs to offer support and
allow upright ambulation has permitted the adaptation of the upper limb, the arm, to allow precise
interaction with the surrounding environment.
35.3 Reconstruction oftheLower
Limb: Why Is It Needed?
The lower limb may need to be restored for
multiple reasons. Originally, lower limb reconstruction was required as an alternative to
amputation, which was the principal treatment
for war injuries. Amputation allows for the
removal of necrotic tissue and infection, with
the aim of saving the victim’s life, but can sacrice potential function and rehabilitation.
Since World War I, major developments in
applied anatomy, fracture management, wound
care, and sterile techniques, as well as the introduction of antibiotics and anesthesia, have
allowed surgeons to consider the role of limb
salvage, a eld which has greatly expanded
since its introduction.
The eld of reconstruction gained a vast number of options following the improvement of vascular techniques in the 1960s, opening the door
to the microvascular reconstruction era.
Nowadays, war injuries still make up a proportion of the number of people who require
access to advanced techniques in the eld of
lower limb salvage and reconstruction. However,
the scope of injury mechanisms has been added
to with an increasing number of blunt trauma,
thanks to urbanization and industry, as well as
increased diagnosis of lower limb malignancies
and chronic medical conditions, including diabetes and peripheral vascular disease.
Today’s goal in lower limb reconstruction has
not changed much from those originally cited in
the early war victims, with restoration or maintenance of function becoming the essential goal as
these injuries became less life-threatening.
Function involves the need for a stable skeleton,
allowing weight-bearing status, with adequate
soft tissue coverage to nourish and protect the
underlying bone. “Normal” function of the limb
is then more reliant on their rehabilitation of the
limb muscles and joints, with proprioception and
plantar sensitivity key.
End points of reconstruction are also measured by a return of function to a level required
by that individual. Options become dependent on
a balance of anatomical, social, and psychological factors. This functionality can be reduced by
chronic pain and infection, as well as complications with chronic swelling or wound healing.
The aesthetic outcome is also important, but this
should never take priority over the limb’s ability
to function.
35.4 Reconstruction: Easy
Options but aDicult
Choice?
The reconstructive ladder should always be
addressed when considering closure of wounds.
This progresses from secondary healing to primary closure, through the options of grafting to
the more complex local, then distant, free tissue
aps (Fig.35.1), although the “stepwise” assessment to lower limb wounds may not always be
the best approach in lower limb reconstruction.
Today, there are options to supplement the
reconstructive ladder, with the use of negativepressure wound therapy, as well as tissue expansion or prefabrication of tissue, before a denitive
surgery. In the future, it is hoped that adjuncts in
the form of pharmacological therapies and the
use of engineered materials for wound coverage
will become more signicant. Wound coverage
requires many aspects of the patient’s background and present state to be assessed before
making a decision on the most suitable option.
The bed bound patient in their later years with
an infected diabetic foot and chronic leg ulcer
offers a different challenge to that of the 28-yearold with an open fracture, massive skin loss, and
vascular damage following a road trafc incident.
Potentially, the latter has a lifetime of earning
and dependents as opposed to the former, who
may require purely symptomatic relief. The difcult choice then becomes whether you offer
both salvage and amputation or either. It may
seem obvious that amputation in the younger
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Fig. 35.1 Reconstructive
ladder, although the
“stepwise” assessment to
lower limb wounds may
not always be the best
approach in lower limb
reconstruction
431
Free Flap
Pedicled Flap
Local Flap
patient is not preferable, but who says that a simple amputation and prosthesis, allowing a quicker
return to work and normality, is worse than the
potential long-term rehabilitation required with a
complex bone and skin coverage procedure?
This highlights the need for lower limb reconstruction to be made on an individual basis and
involve a multidisciplinary team. The key aspects
being what is missing and what vital structures
are exposed as well in consideration of the following points:
35.4.1 Physical Examination
oftheWound
This will involve inspecting the wound size and
noting the amount of damage and loss to both the
skeletal and soft tissue envelope. All devitalized
tissue should be removed, and this may have an
impact on options for reconstruction particularly
if there is degloved tissue. In addition, the vascular supply to both the area and distal regions
needs to be assessed. This assessment of the
wound is likely to require the input of orthopedic,
reconstructive, and vascular professions to varying degrees. The location of the wound also plays
a large role in the feasibility of reconstruction
options. The surrounding tissue also becomes
important in terms of concurrent injuries, such as
those in crush injuries, radiation changes following radiotherapy elds in malignancy, chronic
Skin Graft
Primary Closure
Secondary Healing
Negative
Pressure
Wound
Therapy
infection, or edema-related changes. Once the
decision of surgical closure of a wound has been
made, appropriate debridement must be undertaken before a nal coverage option is chosen.
35.4.2 Patient Assessment [2]
This incorporates the morbidity and mortality
risk of undertaking the procedure in the elective
patient. Patient age, body mass index, their smoking status, and previous injuries to the limb
involved should be noted. Scars crossing regions
involving local and distant ap options may rule
out these choices. Comorbidities involving cardiac and respiratory disease may discourage a
long general anesthetic and potential intensive
care stay, as well as having an impact on rehabilitation. Diabetes and peripheral vascular disease,
particularly stenosis and atherosclerotic vasculature, will again rule out both donor and wound
coverage options. Angiography is often required,
particularly in the chronic wound as opposed to
the blunt trauma scenario, as a chronic lower
limb wound will often heal adequately as long as
the area is reasonably perfused, and a nonhealing
area due to poor perfusion is unlikely to be successfully grafted. Likewise, nutritional state is
strongly inuential on both chronic wounds and
the healing of the wound coverage options. This
will involve dietician support. Pre-injury dementia and ambulation should also be reviewed to
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determine rehabilitation and compliance with
reconstruction. For the emergency patient, lifethreatening injuries take precedence over everything, and the patient will require assessment in a
structured way, as dened by the Advanced
Trauma Life Support (ATLS) principles [3]. Soft
tissue coverage is needed to aid an infection-free
fracture union. This should ultimately be completed at the same time as bony xation if simple
or local ap closure is achievable. Free ap
reconstruction should be performed on a scheduled trauma list by an experienced, dedicated
senior surgical team in a specialist center, preferably within a week of injury [4].
35.4.3 Rehabilitation andFunctional
End Point
The rehabilitation of the bed bound, chronic
wound against the active, acute trauma patient
will have a strong inuence on what options are
used for reconstruction. Is the procedure for
symptom relief, functional restoration, or functional improvement? Social status pre-injury and
potential rehabilitation options must be assessed.
Occupational therapist and physiotherapist inputs
emphasize the need for a multidisciplinary team
approach to determine the most suitable reconstruction option. Good progress during early
rehabilitation can also determine the successful
return of normality for the patient.
35.4.4 Patient Expectation: Their
Desires andNeeds
Exploring the patient’s psychological state is
equally important. A complication free ap that
saves a patient’s foot is almost wasted if the
patient automatically rejects the rehabilitation
phase. The patient’s motivation and compliance
is critical in the functional end point. The appearance of the reconstruction alongside postoperative pain and swelling is interpreted differently
by each individual and will need individual
assessment. Likewise, it is important to ensure
the patient has a close support system. Offering
counseling to those closely involved may aid the
patient’s recovery. It has been reported that, when
offered, a high percentage of patients (93%)
would prefer a limb salvage procedure in the
traumatic scenario to avoid undergoing amputation [5], and as an option in the chronic wound,
reconstruction provides a chance for the patient
to remain socially independent and maintain or
improve their ambulatory status [6]. This supports patient choice in the reconstructive options,
and all options should be discussed in detail by a
trained expert to the patient to aid end compliance and balance expectations.
Other factors to be aware of in lower limb
reconstruction include, but are not limited by:
1. Cost of care
2. Surgeon’s experience
3. Donor site disability
4. Potential complications
Once these areas have been appropriately
assessed and individually tailored to the patient, a
list of potential surgical options will be made and
offered to them.
35.5 Reconstruction Options:
TheReconstruction
The reconstructive ladder (Fig.35.1) offers a list
of options in terms of surgical closure of the
wound. However, the simplest option is not
always the best option. On top of the above preoperative assessment requirements, a failed technique in lower limb reconstruction can have a
devastating effect on the patient resulting in further tissue and bone loss, deterioration of comorbidities, and functional decit with an end point
involving amputation. For this reason, the best
reconstructive option is often not the easiest
choice but the choice that has the highest chance
of success. For this reason, free ap tissue transfer is often regarded as the cornerstone of lower
limb reconstruction. There has been much debate
on the benets of fasciocutaneous versus muscle
based aps, based on the former being thinner,
often less donor comorbidity whereas muscle
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aps may improve the bone healing and reduce
the infectious load of the wound. The authors
feeling is that the right ap for the right wound
should be the route taken with the wound (size/
location/decit), the patient (comorbidity/outcome need/rehabilitation) and the surgeon (capability/instrument availability) being the key
aspects of this choice.
35.5.1 Direct Closure andLocal
Alternatives
Primary and delayed closure, as well as grafting
of a wound are well-documented options and
should be attempted in both the simple wound,
those where expedited recovery is required, or
where more complex reconstructive failure would
be disastrous.
These options require an adequate blood supply to the wound area and relatively reliable surrounding tissue. Where the blood supply is poor,
involves periosteum stripped bone or where
there is a requirement of soft tissue depth, the
use of reconstructive aps is generally required.
Another option using the nearby soft tissue
envelope includes tissue expansion, a choice
which negates variance in tissue thickness, texture, and color and offers provision of specialist
skin to a region (e.g., hair-bearing). This technique is limited by the reliability of the surrounding tissue but may offer a potential donor
site for both direct closure and local ap coverage. Tissue expansion requires time to expand
the tissue, so may not be an acute option, and is
also known to have a high percent of complications in the lower limb in particular (over 70%).
35.5.2 Flap Reconstruction
Flap reconstruction options can be broken down
to local and free ap descriptions. In general
aps can be described based on the blood supply
to the ap, the location of the donor site, and the
type of tissue being transferred.
The rst uses of ap reconstruction initially
involved movement of skin around pivot points,
with these “local aps” designed using tissue
local to the wound. They will require their blood
supply to be intact from the injury, whereas free
aps are based along a distant donor site. Flaps
utilize composite tissue blocks and may include
the skin, muscle, bone, fascia, and combinations
of these.
Local cutaneous aps can be based along random pattern or axial vascular circulations using
the subdermal blood supply. Random pattern
cutaneous aps are limited by the arc of rotation
and decreased bacterial resistance, as well as a
general rule of a 2:1 ratio between the length and
base of the ap used in the lower limb. The discovery of axial pattern aps, where the ap is
perfused by a dened vessel or angiosome, has
permitted the use of longer aps.
Other options for local aps to aid take have
included delayed transfer. An example of this is
“the arm carrier” technique, involving abdominal
aps being transferred to a donor site on the arm
before nal transfer to the leg. This technique is
still dependent on the nal location wound environment for the take to be successful.
The discovery of random pattern skin aps led
to an investigation into vascular anatomy, and
consequently it was found that local aps could
involve muscle, with transposition of either the
muscle or a musculocutaneous block supplied by
the muscle’s dominant vascular pedicle. This
nding was further supplemented by the discovery regarding fascial vascular supply and that the
deep fascia, with or without skin, also allowed
reliable ap creation. In 1981, Ponten [7] noted
skin survival in a patient correlated with a single
perfused vessel shown on angiography. This led
him to raise a calf-based ap including the fascia
and sural vessels, prompting a variety of new discoveries in ap options [8].
The use of cutaneous, musculocutaneous, and
fasciocutaneous aps based along specic dominant vascular pedicles has allowed the direct
transfer of tissue which is less dependent on the
wound bed blood supply. They also introduce
new circulation to the area and offer a more reliable and larger wound coverage option. As our
understanding continues to develop, it has been
noted that both true and “choke” anastomoses
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exist between the perforator angiosomes allowing longer aps to be more successful [9]. The
pedicled aps are restricted by their arc of rotation, something which was greatly increased
compared to random pattern skin aps. The
advancement of microscopy, micro-instruments,
and sutures has allowed the development of free
ap surgery, which essentially involves detaching
a known pedicle-based tissue composite unit and
transplanting it to the wound area and anastomosing it to a suitable receptor artery and vein in
proximity to the wound. Microsurgery has
allowed the direct transfer of large tissue units
from distant donor sites, allowing wounds to be
covered and reconstructed based on ap suitability rather than wound proximity.
Free ap coverage has helped reduce the often
bulky pedicled ap seen, particularly in muscle
aps. It also allows direct closure in the majority
of the donor regions. A skin graft to this site
should only be used if the donor ap is of special
signicance (superiority in function/shape etc.).
Igari etal. [10] reported end-to-side and endto- end anastomosis of latissimus dorsi free aps
to the vascular graft on these wounds with 85%
ap survival and 100% limb salvage rate. This
technique helps with the problem of exposed
functional tissues when the wound is debrided.
Free ap reconstruction offers wound coverage but does not improve the distal circulation.
However, there are reports of revascularization of
critical limb ischemic wounds with free ap coverage being offered as a single procedure with
reasonable results [11, 12].
In the traumatic scenario, all open fractures
require avascularized soft tissue envelope free of
infection to allow appropriate bone healing.
The use of negative-pressure wound therapy
(NWPT) can temporarily be used as a substitute
for denitive ap coverage [4].
35.5.3 Flap Vascular Anatomy
The blood supply of the raised ap is key to its
survival. The classication of aps can be
described by the vascular source. As noted, random pattern aps have no specic named vessels
supplying them, while a recognized artery or
Table 35.1 Muscle/musculocutaneous ap classication
Type Pedicle Example
I One vascular pedicle Tensor fascia lata
II One dominant pedicle
and minor pedicles
III Two dominant pedicles Gluteus maximus
IV Segmental pedicles Sartorius
V One dominant and
secondary segmental
pedicles
Table 35.2 Fascia/fasciocutaneous ap classication [14]
Type A B C
Direct
cutaneous
pedicle
Septocutaneous
pedicle
Gastrocnemius
Gracilis
Soleus
Serratus anterior
Extensor halluces
longus
Latissimus dorsi
Pectoralis major
Musculocutaneous
pedicle
group of arteries forms an axial-based ap. The
variation in axial blood ow into different
muscles is complex, and Mathes and Nahai [13]
attempted to subclassify this form of ap vasculature. This classication is well described in
reconstructive literature and summarized in
Table 35.1. The blood supply to fascial-based
aps has also been classied in Table35.2.
35.5.4 Flap Failure
andComplications
Flap complications can be wound specic, vary
from reconstructive unit to unit, and are dependent on the ap used. They include failure of the
ap, involving partial or total necrosis; hematoma
and seroma collections (for which the use of postoperative drains is not uncommon); and wound
dehiscence and infection. Donor site morbidity
should be negligible but could involve a reduction
in function, particularly in aps involving muscle
components. In using free aps, it should be noted
that vein grafts are frequently required, and in
particular the deeper venous network is targeted
for anastomosis due to a predisposition of the
supercial system to spasm. The arterial anastomosis if often performed in an end- to- side technique due to vessel mismatch and the very high
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chance of a single-vessel perfused limb. A single
vessel leg is not a contraindication to free ap
limb salvage. Angiography may be useful in planning reconstruction but does not correlate with
vessel ow and can miss segmental vessel injury.
Pressure ulcer coverage is particularly complicated, usually due to issues regarding the continuation of pressure at the reconstructed site. One
paper quotes ap complications involving ischial,
sacral, and trochanteric wounds of 87 complications in 421 (21%), with suture line dehiscence
(31%), infection (22%), hematoma (19.5%), partial necrosis (13.7%), and total necrosis (10.3%)
noted [15]. This complication needs to be noted
in patients where lower limb trauma may predispose to pressure to reconstructed regions either in
the rehabilitation period or long-term.
35.5.5 Choice ofReconstruction:
TheFlap Options [16]
Traditionally the use of local muscle aps proximally and free aps distally in the lower limb has
been used, although improvement in local ap
reliability has allowed their use throughout the
limb [17].
35.5.5.1 Local Flap Reconstruction
Random pattern cutaneous aps can be limited
by their vascular input. There are suggestions that
the detection of perforators can be made by using
thermal imaging to improve the sensitivity of
current Doppler and anatomical landmark techniques [18]. In particular, thermal imaging may
help locate the “choke” anastomoses which help
aid apper fusion and drainage [19].
“Propeller” flaps are well documented as an
option for the majority of coverage in the
lower limb, particularly below the knee [20,
21]. The propeller flap is an insular flap mobi-
lized through an axial rotation to cover a
defect (like a propeller), with perforator propeller flaps pivoting on a perforating vessel.
Most perforator-based flaps can be utilized in
a propeller flap idea including the ALT, TFL,
and groin flaps, and for the distal limb the
peroneal and posterior tibial arteries are commonly used for lateral and medial defects,
respectively (Fig.35.2).
ab c
Fig. 35.2 Propeller ap based on posterior tibial artery. (a, b) Defect and initial design. (c) Final position with donor
defect grafted. Note movement of tattoo when propeller ap is rotated 180° to cover defect
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The posterior tibial artery provides multiple
cutaneous perforators but at unpredictable intervals. However, there are three distinct clusters
found at predictable distances of 4–9 cm,
13–18cm, and 21–26cm proximal to the medial
malleolus and are typically of larger caliber than
other options more proximal on the limb. When
using peroneal artery-based aps, it should be
noted that the blood supply tends to lie posterior
to the bula as opposed to over it when designing
the skin paddles. This provides good form
and function for elective and traumatic defects,
offering an option in forefoot cover [22].
However, a recent literature review reports up to
16% of aps suffering partial necrosis, with a
third of them involving the whole ap [23].
Both the peroneal and anterior tibial artery
aps have small pedicles, around 3 cm, and
sub- centimeter diameters, meaning their use as
free aps is limited. They are both type B fasciocutaneous aps and can be harvested with
the supercial peroneal or saphenous nerve for
sensate aps.
V-Y aps, as described by Blasius in 1848
[24], are another option, particularly around the
ankle and lower leg and can provide a sensate
ap to the region [25].
Bipedicled aps are random pattern aps but,
due to two pedicles, their continued viability is
improved. They are a ap gaining popularity for
closure of lower limb wounds, as is the keystone
ap [26, 27].
The ad hoc perforator is a local ap that can
be based on any type of perforator. Its concept
was rst alluded to by Quaba etal. in 1990 [28]
and is analogous to the freestyle free ap concept of Wei and Mardini in 2004 [29]. With
increased understanding of the cutaneous circulation and a sound knowledge of regional vascular anatomy, the reconstructive surgeon can
tailor their approach to the presenting defect
without being constrained by a previously
described local ap or perforating vessel. Careful
Doppler mapping and/or preliminary exploration is performed to identify a perforator adjacent to the defect. The presence of a positive
Doppler signal in the territory of the defect
allows planning and execution of the ap with-
out the need to dwell on anatomical landmarks
or variations [30].
For open fractures of the lower limb, local fasciocutaneous aps should be used in low-energy
tibial fractures (Fig.35.3). As long as there is no
vascular compromise by the initial injury, these
can be used, along with free fasciocutaneous
aps, in metaphyseal injuries (particularly around
the ankle) [31]. Muscle aps would be suggested
by experimental data in open tibial shaft fractures
or where the blood supply is compromised, possibly helping to reduce both the healing time and
risk of deep infection [31].
35.5.5.2 Fasciocutaneous Flaps
1. Groin
The earliest axial-based fasciocutaneous
ap, the groin ap, has been used as both a
free and pedicled ap (Table35.3) [32] providing a substantial amount of both tissue and
skin. Often needing subsequent debulking
and due to the fact that it is a hair-bearing
area, this ap can be a poorer aesthetic match
compared to other options. The short venous
supply to the region also causes an increased
risk of ap failure. Often taken using a pedicle approach from the supercial circumex
iliac artery, the groin ap allows up to
20 × 10 cm aps to be harvested alongside
direct closure, and twice this with grafting of
the donor site. The groin ap is a type A fasciocutaneous ap.
2. Medial Thigh and Transverse Upper Gracilis
Typically using the anterior septocutaneous
artery and the venae comitantes from the supercial femoral vessels, this ap can be also be
raised more anteriorly by using the lateral
femoral circumex artery, where it is more
commonly referred to as the anteromedial
thigh ap. The saphenous vein can be utilized
to aid venous drainage as well as keeping a
sensate ap when the medial anterior cutaneous nerve of the thigh is raised; the medial
thigh ap is useful both as a free and pedicled
ap. The latter will help cover wounds involving the perineum, groin, and thigh up to
10× 20 cm in size. This skin paddle is now
utilized in the transverse upper gracilis (TUG)
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a
b
c
Fig. 35.3 Reconstruction of bilateral leg defects with
exposed tibia. (a) External xation in situ for tibial fractures. (b) Right leg reconstruction. Bony defects are cov-
ered with ad hoc perforator ap laterally and posterior
tibial perforator ap medially. Both donor sites grafted.
(c) Left leg required only skin grafting to defect
Table 35.3 Groin/SCIA ap
Groin/SCIA ap
Flap
attributes
Artery Supercial circumex iliac artery
Vein Cutaneous vein draining into saphenous
Pedicle 2–5cm, generally short pedicle but can be
Nerve N/A
Cutaneous ap taken with fat
Can be harvested as free or pedicled ap
(external iliac/supercial femoral artery)
1–2mm
system
extended by more lateral skin paddle
ap which is can be raised solely on medial
femoral circumex artery perforators through
the gracilis. The medial thigh ap has a pedicle of 2–4cm with a 1.5mm diameter. This is
a type B ap.
3. Lateral and Posterior Thigh
This ap and the posterior thigh ap
exploit the profunda femoris perforating
branches. Of the four, the rst supplying the
lateral thigh is used for proximal regions
including the trochanteric and ischial areas,
and the third the posterior thigh [
33]. The lat-
eral thigh ap may also be harvested to
include the lateral femoral cutaneous nerve as
it can in the ALT ap. The lateral thigh ap
often has a pedicle of 5–6cm with a diameter
between 1 and 2mm. This is a fasciocutaneous type B ap.
4. Anterolateral Thigh (ALT) (Table35.4)
Taken from the descending branch of the
lateral femoral circumex artery and thanks to
an extended pedicle, the ALT is typically used
as a free ap. A 7×20cm skin paddle can be
raised with a tight closure of the donor site. A
type B and C fasciocutaneous ap, it is well
used in head and neck reconstruction and
allows a relatively slim ap for upper limb
reconstruction. Its use as a pedicled ap or
propeller ap is also useful for defects across
the groin to knee regions (Fig.35.4).
5. Sural
The sural artery allows probably the lon-
gest pedicled fasciocutaneous or fascial ap
(Table 35.5). Also, with the ability of being
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Table 35.4 ALT ap
Anterolateral thigh ap (ALT)
Flap
attributes
Artery Descending branch of lateral femoral
Vein Slightly larger than artery, draining into
Pedicle ~7cm, dependent on perforator entry to
Nerve Lateral femoral cutaneous nerve of the
Skin, fat and fascial ap, pedicled or free
ap options
Skin paddle can be up to 12×25cm
Can be harvested as only an adipofascial
or fascial ap
Vastus lateralis muscle can also be
included in the ap dissection if required
circumex artery (profunda femoral
trunk) 1.5–3mm
profunda femoral vein junction
ap and position skin paddle
thigh can be harvested with this ap,
entering at proximal part of design
reversed, this ap can cover defects around
the knee, anterior and posterior and upper
third of the leg, as well as proximal foot
defects. A type A fasciocutaneous ap skin
aps of up to 12 x 20cm can be raised. The
Medial Sural Artery Perforator (MSAP) ap
has slowly gained popularisation. This utilises
the same pedicle that the medial gastrocnemius ap would normally be harvested on so
does mean sacricing this muscle ap, but the
fasciocutaneous ap dissection allows a long
pedicle with often little disruption to the
underlying muscle function.
6. Saphenous
Coverage of the knee can be achieved by
raising this ap using the saphenous artery and
venae comitantes. This is a continuation of the
descending genicular branch of the supercial
femoral artery. The saphenous artery perforator ap is supplied by septocutaneous perforators supplying the medial thigh skin above the
knee. The saphenous artery also supplies
another region of the skin anterior and medial
aspects of the leg below the knee and originates from the descending genicular artery. A
line from the anterior superior iliac spine to the
medial epicondyle of the tibia approximates to
the sartorius muscle, the key landmark in nding the vascular pedicle. The cutaneous
branches are found between 3 and 10cm from
the saphenous artery origin which lies toward
the adductor canal. It has been reported in
varying degrees that the saphenous artery joins
the dorsalis pedis artery in the foot allowing
distal leg and foot coverage. With a more difcult dissection than those listed above due to
increased vascular anatomy variance, this ap
can also be reversed and includes an osteofasciocutaneous option (from the medial femoral
condyle) using the articular branches of the
genicular artery. Skin paddles 7× 20cm are
typical, with a section of sartorius occasionally
taken with the raised tissue to aid ap survival
rates. The pedicle can be 5–15cm length with
a diameter of 1–2 mm. This is a type A ap
(Fig.35.5).
35.5.5.3 Muscle and
Musculocutaneous Flaps
1. Gluteus Maximus
Being the largest muscle of the body and
having both two dominant and two minor
pedicles, this allows for a high degree of versatility. Reliable coverage of the buttock, hip,
perineal, and upper thigh regions is achievable. Raised either from the lateral femoral
circumex artery to allow posterior thigh
coverage in a reversed technique, or off of
one of the gluteal arteries (superior or inferior) with the muscle split preserving function [34] and tissue to cover either anterior or
posterior defects. These can incorporate
either only muscle or muscle and skin coverage options.
(a) The superior and inferior gluteal perfora-
tor aps (SGAP/IGAP) have replaced gluteal muscle aps as they reduce buttock
morbidity and are a mainstay of breast
reconstruction. They allow a fasciocutaneous ap to be raised from the superior
or inferior gluteal arteries with a 3–4mm
artery caliber, often larger veins, and pedicles up to 7cm, with the IGAP-based ap
also known as the posterior or gluteal
thigh ap and not to be mixed up with
Song’s description of a posterior thigh
ap raised on the third perforating branch
of the profunda femoris artery [35]. This
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