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2 Surgical Assessment
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23
abc
Fig. 2.3 (a) Common carotid artery isolated for anastomosis. (b) Use of a punch biopsy tool to create the puncture. (c)
The puncture in the CCA ready for end-to-side anastomosis
thoracoacromial artery is a branch of the axillary
artery and has been described successfully when
other vessels are unavailable. The vessels are
very caudal, and so a ap with a long pedicle
length is often needed, and the vein is often very
caudal, frequently requiring a vein graft [24].
Also, harvesting the thoracoacromial artery will
compromise any potential for utilizing a pectoralis major myocutaneous pedicled ap as a salvage option. Contralateral neck arteries can also
be used as mentioned earlier. However, as anticipated, a longer pedicle length is needed to reach
the contralateral neck vessels. Additionally, vein
grafts, or a Corlett loop, can be used to reach the
contralateral neck vessels where needed [25].
The Corlett loop will be discussed further in the
next section.
Venous Options intheVesselDepleted Neck
Venous drainage is often the rate-limiting step in
the vessel-depleted neck and may require creative solutions by the reconstructive surgeon to
achieve adequate venous drainage. The internal
jugular vein and the external jugular vein are the
main venous systems used for venous anastomosis. However, these options are often unavailable
in the vessel-depleted neck and so alternative
options are usually needed. In the above section,
we discussed the accompanying veins of the
supercial temporal system, the transverse cervical system, and the internal mammary vessels.
Vein grafts can be utilized where needed to
lengthen the available venous or arterial options.
However, vein grafts require two anastomoses for
each vessel, and hence have a higher rate of failure in several studies [26]. The cephalic vein can
be harvested and rotated into the neck defect for
venous anastomosis. Often, this vein has not been
affected by prior surgery or radiation. The
cephalic vein drains directly into the axillary vein
and can be harvested relatively easily. The
cephalic vein travels from the axillary vein
through the coracoclavicular fascia proximally. It
then travels between the pectoralis major and the
deltoid muscles before travelling in the groove of
the lateral border of the biceps brachii. It then
crosses supercial to the musculocutaneous
nerve and then courses between the brachioradialis and the brachii muscles distal to the elbow. A
curved incision can be extended from the neck
incision along the deltopectoral groove to locate
the vein and follow it distally [26]. Once adequate length is acquired, it can then be rotated
and transposed into the neck (Fig. 2.4). Care
needs to be taken to avoid the cephalic vein from
kinking at the coracoclavicular fascia.
When a suitable local artery and vein are not
available, the technique of a Corlett loop can be
used. This technique utilizes the long length of
the cephalic vein to achieve both arterial and
venous vessels for microvascular anastomosis. In
this technique, the cephalic vein is harvested as
described above, and it is rst anastomosed to the
contralateral neck branches of the external carotid
artery forming a temporary arteriovenous stula.
The vessel is then divided, and the proximal end
is attached to the vein of the ap, and the distal
24
abc
O. Breik and S. Parmar
Fig. 2.4 (a) Incision markings for cephalic vein transpo-
sition for a known vessel-depleted neck. (b)Exposed
cephalic vein along the deltopectoral groove. The ap
pedicle vessels are clamped here to approximate the
length needed for the cephalic vein transposition. (c)
end (which was anastomosed to the contralateral
neck artery) is attached to the artery of the ap
[25]. This can be performed as a single-stage or a
two-stage delayed procedure [27]. The technique
of forming an arteriovenous stula has been well
described in limb reconstruction, but it is rarely
used in head and neck reconstruction [27]. The
study by Lin etal. demonstrated a higher rate of
failure with two-stage arteriovenous stulas [27].
All reported cases in the head and neck have been
single-stage procedures [25, 28].
Extreme Circumstances
When suitable locoregional alternative vessels
are not available, surgeons can consider the pedicle of previous aps used for reconstruction. The
options in this scenario include (1) using a side
branch of the proximal pedicle; (2) assuming that
the former ap has developed alternative vascularization, sacricing the current pedicle vessel
using the pedicle as recipient vessels; and (3)
using the distal end of the previous ap pedicle
for ‘ow-through’ anastomosis20. Where no possible vessels are available, Wolff et al. have
described the use of extracorporeal perfusion
devices to maintain vascularity to a ap while it
develops independent blood supply. The protocol
aims to accelerate neovascularization and autonomization of the ap within 2 weeks of reconstruction [29].
Cephalic vein transposed and tunnelled under the clavicle
to reduce the risk of compression from external neck pressure and swelling. An adequate space is obviously needed
under the clavicle to allow the vein to safely distend under
the clavicle
Flap Selection
Selecting a ap is a combination of art and science—there are many different aps to choose
from, and while some may be suggested by particular scenarios, there is rarely a single possible
choice. The clinician should consider the pathology, the patient as a whole (including their opinions and priorities), what previous treatment has
been performed, and the availability of necessary
equipment and/or expertise.
Pedicle length in particular is important in the
reconstruction of maxillary defects as there are
few suitable donor vessels in close proximity.
In soft tissue reconstruction, the choice of ap
depends on the type of skin, the thickness of skin,
and the colour of skin required. For partial glossectomy defects, often a radial forearm free ap
reconstruction provides thin, pliable skin that can
seal the oral cavity from the neck and provide
enough pliability of skin to allow tongue extension
and movement from the residual tongue. When the
base of tongue/oropharynx is likely to be involved,
or greater than a hemiglossectomy is planned, then
more skin and soft tissue bulk may be required,
and hence an anterolateral thigh ap is the workhorse ap for these reconstructions. Alternatives
for soft tissue aps include medial sural artery perforator (MSAP) aps, Supercial circumex iliac
artery perforator ap (SCIP) lateral arm ap,
TDAP, scapula (soft tissue only), and freestyle free
aps based on unnamed perforators.
2 Surgical Assessment
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Bony reconstruction however has more specic options. These include the bula free ap,
deep circumex iliac artery (DCIA), aps based
on the subscapular artery system, composite
radial free ap, and medial femoral condyle free
ap. Once a bony ap has been selected, it is now
considered best practice to undergo preoperative
virtual planning. This can be done with traditional
dental models, 3D software, rapid prototyping, or
a combination of techniques. CAD/CAM techniques have revolutionized bony reconstruction.
Cutting guides can now be made to perform the
resection, and the use of cutting templates allows
accurate 3-dimensional reconstruction. Plates
used to stabilize the bone can also be custommade. These techniques have improved reconstructive results and also save intraoperative time.
In this section of the chapter, we will briey
discuss the advantages and disadvantages of the
most common free aps, and key preoperative
planning needed for these aps.
Radial Forearm Free Flap
The radial forearm free ap is the most commonly
used free ap for intra-oral soft tissue reconstruction. The reliability of the anatomy, presence of
thin pliable skin, and quick harvest make it an
ideal option to consider. Due to its pliability, it is
ideal for defects involving moving structures like
the soft palate, lips, and tongue. It is our preferred
ap for partial glossectomy defects, oor of
mouth defects, buccal mucosal defects, oropharyngeal defects, and posterior maxillary defects.
Disadvantages
• Donor site must be skin grafted.
• Poor aesthetics of donor site.
Preoperative Planning
Clinical examination of the forearm is necessary
to ensure no previous scars or evidence of interventions where the radial artery has been harvested. Allen’s test should be performed to ensure
adequate collateral supply. If Allen’s test is
inconclusive, then a duplex US should be considered to ensure normal vascular anatomy.
Anterolateral Thigh Flap
The anterolateral thigh free ap has become
increasingly popular since its rst description in
1984. This ap is based on various perforators
from the descending branch of the lateral circumex femoral artery and its associated venae comitantes. It is a versatile ap, which can be harvested
as a subcutaneous, fasciocutaneous, musculocutaneous, or adipofascial ap, making it an option
for a variety of applications in the head and neck.
It can also be harvested as a chimeric ap.
Additionally, the donor site can often be closed
primarily and heals with acceptable donor-site
morbidity. The pedicle is also long, potentially
7–16cm.
Advantages
Advantages
• High-quality thin skin produced.
• Long, large-calibre, reliable pedicle.
• Very reliable anatomy.
• Choice of venae comitantes or cephalic vein
or both for venous drainage.
• Allows two-team operating.
• The pedicle is long and possesses large- calibre
vessels.
• Up to 25cm diameter, skin paddle can be harvested with only one perforator.
• It can be harvested as a chimeric ap.
• Primary closure of the donor site is often
possible.
• It allows a two-team approach.
26
O. Breik and S. Parmar
Disadvantages
• It is technically more demanding.
• It has high variability in the position of
perforators.
• In very rare cases, there may not be a perforator.
Preoperative Planning
Clinical examination of the leg will identify any previous scars, surgical interventions, or injuries. Pinch
test will give a clue to the thickness of the skin.
Especially in oral cavity reconstruction, bulkiness of
the ap may render the ALT inappropriate. Doppler
within a 3cm radius circle around the centre of the
line from the superolateral aspect of the patella to the
ASIS may demonstrate likely position or availability
of perforators (Fig.2.5). However, this is not generally accurate, and the only way to check for perforators is to make an incision and check.
Fibula Free Flap
The bula is the ‘workhorse’ ap for the reconstruction of bony defects in the head and neck. It
provides a great length of high-quality bone, which
is suitable for osseointegrated implants, and has a
long, large-calibre, reliable pedicle. It can also be
harvested with skin, although the skin paddle is
less reliable than the bony component. The skin
defect can also be slow to heal, even when grafted,
and so where appropriate, we sometimes use muscle and subcutaneous fat alone to line intra-oral
defects, which we nd generally mucosalizes well
and reduces intra-oral bulk. It is the ideal ap for
long-segment mandibular defects, mandibular
defects involving the temporomandibular joint,
and low-level maxillectomies [30–32]. It is also
the ideal ap for immediate implant surgery and
virtual planning. It’s exact shape and the pedicle
orientation allows for application of accurate surgical guides, and it has a good bicortical structure
that allows for good primary stability of the
implants at the time of insertion.
Fig. 2.5 Markings on the anterolateral thigh with the dotted line extending from the ASIS to the superolateral
aspect of the patella. The dotted circle demonstrates 3cm
radius from the centre of the line, and the black dots correspond with the perforators identied on Doppler
Advantages
• Large length of high-quality bone (25cm).
• Long pedicle (15cm).
• Can provide skin for reconstruction of intraor extra-oral defects.
• Bone is suitable for placement of osseointegrated implants.
• Allows two-team approach.
Disadvantages
• Not possible in all patients—Patient may not
have adequate three-vessel ow to the foot;
hence, a bula ap may jeopardize the vascularity of the foot.
• Skin paddle is not as reliable as the bony
component.
• Defect closure requires grafting if skin is
taken.
• Healing of donor site can be slow, requiring
lengthy specialist wound care.
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• Unaesthetic donor-site scar.
• Can cause foot drop if peroneal nerve
damaged.
Preoperative Planning
Clinical examination of the lower leg will identify any previous scars, surgical interventions, or
injuries. Palpate the pulses of the foot, and look
for evidence of venous stasis and vascular insufciency in the form of venous skin changes, varicosities, or peripheral oedema. All of these
features are contraindications for bula free ap
reconstruction.
Imaging
Preoperative angiogram—either a CT angiogram
or an MR angiogram is necessary when planning
for a bula free ap reconstruction. This is vital
to ensure normal trifurcation of the popliteal
artery into anterior tibial, posterior tibial, and
sural arteries and to ensure no signicant atherosclerotic narrowing of the vessels due to peripheral vascular disease. This is necessary because
in 0.2–8% of the population, the dominant blood
supply to the foot is the peroneal magna artery.
As mentioned above, in these cases, bula free
ap harvest is an absolute contraindication, as it
risks vascular compromise to the foot.
Deep Circumex Iliac Artery Flap
The DCIA ap provides a good quantity and
quality of bone, which has contours that can be
adapted to the mandible or maxilla. It can also
provide vascularized muscle for soft tissue coverage, but the traditional skin paddle was not exible. More recently, perforator-based skin paddles
have overcome this disadvantage.
There are also questions over its reliability: a
meta-analysis of nearly 10,000 composite free
aps suggested that DCIA aps were less reliable
overall than other composite aps for mandibular
reconstruction (6.2% ap failure rate vs. 3.4% for
all other aps combined) [33]. Furthermore, closure of the DCIA ap is not trivial, and inadequate closure can lead to troublesome incisional
hernias.
However, it is ideal for reconstruction of the
dentate mandible and high-level Brown class 3
and 4 maxillary defects.
Advantages
• Good quality and quantity of bone (up to
14cm) with curves suitable for mandibular or
maxillary reconstruction (important for the
dentate mandible and class 3 and 4 Brown
defects).
• Can provide muscle and skin for reconstruc-
tion of intra- or extra-oral defects.
• Bone is in excellent quality for placement of
osseointegrated implants.
• The donor-site scar can be concealed by
clothing.
• Allows two-team operating.
Disadvantages
• Short pedicle (6cm), but this can be improved
by raising the ap posterior to the anterior
superior iliac spine.
• Post-operative mobilization is slow and
painful.
• Less reliable than other composite aps.
• Risk of donor-site hernia.
• Defect closure is laborious.
• Associated soft tissue is bulky and inexible.
Preoperative Planning
Clinically, examine the pelvis, palpating for the
iliac crest. Look for scars from previous abdominal surgery. Obese patients make raising the
DCIA more difcult.
No specic imaging is required for the DCIA
free ap preoperatively.
28
O. Breik and S. Parmar
Subscapular Artery System Flaps
The scapular/parascapular ap and scapular tip
aps are versatile aps that are notable for providing excellent skin coverage, the possibility of a chimeric ap, a good amount of high-quality bone, and
an aesthetic, low-morbidity donor site. Furthermore,
the aps are characterized by great exibility, with
the osseous and cutaneous components able to be
positioned independently. The downsides are that it
is most commonly harvested in lateral decubitus
position to harvest the ap, which makes two-team
simultaneous operating all but impossible, greatly
increasing the overall operative time.
The true scapular ap is taken with the horizontal branch of the circumex scapular artery.
The parascapular ap is based on the descending
branch: choosing between them is largely down
to the preference and experience of the surgeon.
A chimeric, dual-paddled ap can also be taken
with one paddle arising from each branch. The
edge and/or tip of scapula can be taken as the
osseous component, providing good-quality bone
and a ap with great 3-dimensional exibility.
The scapular ap is ideally suited to elderly
patients for mandibular reconstruction, patients
where the bula is unsuitable for any reason.
The scapula tip can be harvested independently based on the angular branch of the thoracodorsal artery. This ap provides thinner bone
than the true scapular ap but has a much longer
pedicle (up to 17cm) and can be harvested with
the thoracodorsal artery perforator and part of
latissimus dorsi. The scapula tip is particularly
suited to maxillary reconstruction considering its
shape and long pedicle.
Advantages
• Large amount of good-quality skin.
• Skin paddles have considerable exibility
(independent of each other and the bone)—
allows simultaneous reconstruction of skin,
bone, and mucosal defects with a single ap.
• Skin has good colour match with facial skin.
• Good-quality bone, up to 14cm.
• Very reliable anatomy.
• Reliable pedicle of good diameter.
• Good-quality bone.
• Low donor-site morbidity.
• Long pedicle for scapular tip free aps (up to
17cm).
Disadvantages
• Short pedicle (3–4cm) for lateral border scapula free aps.
• Need to move the patient into decubitus
position.
• Two-team operating is difcult.
• The skin paddles can be too bulky for intraoral reconstruction, especially in obese
patients.
Preoperative Planning
Clinically examine the back for scars, and palpate for any scapula abnormalities.
Generally, vessels in this area of the body are
rarely affected by peripheral vascular disease,
and so no angiography is needed to investigate
these vessels.
Virtual planning can be performed by captur-
ing the scapula bone from the CT chest performed for staging purposes.
Composite Radial Forearm FreeFlap
The radial forearm ap is the most commonly
used and most reliable soft tissue ap for intraoral reconstruction. In addition to the pliable,
thin skin, if a composite ap is required, a moderate amount of unicortical bone can also be harvested without major modication to the
technique. This bone is often inadequate for
implant rehabilitation. It is ideally suited to
reconstructing edentulous mandibles and smaller
orbitomaxillary defects.
2 Surgical Assessment
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Advantages
• High-quality thin skin produced.
• Long, large-calibre, reliable pedicle.
• Choice of venae comitantes or cephalic vein
or both for venous drainage.
• Straight, unicortical bone (up to 10 cm)
(Fig.2.6).
• Allows two-team operation.
Fig. 2.6 A composite radial harvested with 10 cm of
bone for mandibular reconstruction
Disadvantages
• Risk of post-operative fracture of radius—risk
minimized by using a cutting guide and plating of the radius (Fig.2.7).
• Bone is often not suitable for osseointegrated
implants.
• Donor site must be skin grafted.
• Poor aesthetics of donor site.
Preoperative Planning
Clinical examination of the forearm is necessary
to ensure no previous scars or evidence of interventions where the radial artery has been harvested. Allen’s test should be performed to ensure
adequate collateral supply. If Allen’s test is
inconclusive, then a duplex US should be considered to ensure normal vascular anatomy.
CT forearm is ideal for virtually planning the
amount of bone being harvested to minimize the
risk of radius fracture post-operatively. CT scans
can be used to design a cutting guide to take the
right amount of bone and to prebend a distal
radius plate reducing the risk of post-operative
fracture.
a
d
Fig. 2.7 Virtual plan for a small composite radial free
ap. (a) 3D printed radius bone with the planned bone
harvest. (b) Planned distal radius plate adapted to the 3D
printed radius bone. (c) Distal radius plate and titanium
b
e
c
cutting guide for intraoperative adaptation to the radius.
(d) Radius cutting guide in situ. (e) Pre-adapted distal
radius plate in situ
30
O. Breik and S. Parmar
Flap Selection intheVesselDepleted Neck
Reconstructive surgeons tackling these cases
need to have a wide spectrum of free microvascular aps within their armamentarium. In a recent
systematic review of microvascular reconstructions in the vessel-depleted neck, 329 reconstructions from 26 included studies were performed
with a vast diversity of 18 different aps used
[18]. The most commonly used were the anterolateral thigh ap (ALT) and the radial forearm
free ap (RFFF). When choosing the ideal ap,
several factors need to be considered. Firstly,
which options are available as some aps may
have already been utilized in previous surgeries.
Secondly, adequate pedicle length is particularly
important in these patients as they are already
compromised in terms of vessels available for
anastomosis. Commonly used soft tissue aps for
head and neck reconstruction with the longest
pedicle lengths are radial forearm aps, anterolateral thigh aps, latissimus dorsi aps, and rectus abdominis aps, respectively. Composite
aps with the longest pedicle lengths are bula
and scapula-tip aps (utilizing the angular branch
of the thoracodorsal artery as the pedicle).
Where possible, the surgeon can also plan to
modify a particular well-known ap to increase
pedicle length through a variety of ways. The
deep circumex iliac artery (DCIA) ap pedicle
length can be increased by harvesting the bone
more posterior to the anterior superior iliac spine
than usual. The scapula free ap pedicle can be
lengthened by harvesting the thoracodorsal artery
and anastomosing to the distal end of the thoracodorsal artery. Blood will travel in a reverse
ow into the circumex scapular artery supplying the ap. During planning for these cases, the
reconstructive surgeon should consider their plan
A but always have a plan B and plan C for the
patient depending on which vessels are identied
on neck exploration. Pedicled reconstructive
options need to be considered in cases when no
good recipient vessels are identied. Most commonly used include pectoralis major myocutaneous aps, pedicled latissimus dorsi aps,
deltopectoral aps, and supraclavicular artery
aps [18, 34].
Rehabilitation andVirtual Planning
Planning for rehabilitation should not be an
afterthought but should be considered at the time
of initial surgical planning. What are the patient’s
long-term goals from treatment? What factors
are important for each individual patient’s quality of life? Considering these factors will help
guide the chosen reconstruction and the chosen
approach. Sometimes, a microvascular free ap
is not the ideal option, and small defects can
often be managed with skin grafts and prostheses to help the skin graft to take (Fig.2.8). In the
majority of cases however, microvascular free
aps are required, and rehabilitation can be made
much more accurate with the availability of virtual surgical planning, and advances in virtual
surgical planning have allowed for immediate
jaw reconstruction at the same time as surgery
ab
Fig. 2.8 86-Year-old female patient who had a small
anterior mandibular alveolar SCC.She underwent a marginal mandibulectomy and split-thickness skin graft for
reconstruction. The skin graft was inset and supported by
a denture dressed with coe-pak dressing for 2weeks. (a)
Appearance of the defect at 2weeks and 6weeks postoperatively. (b) Skin graft at 3 months demonstrating
good sulcus depth and a partial denture for rehabilitation
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[31]. However, the majority of patients will have
delayed rehabilitation, and the way for rehabilitation can be prepared by accurate custom
patient- centred reconstructions. There is a wide
variety of ways in which 3D computer-aided
design (CAD) and computer-aided manufacturing (CAM) can be used to aid the surgeon in
their reconstructive goals ranging from just
printing biomodels to allow a reconstruction
plate to be bent on the model (Fig.2.9) to fully
guided 3D printed cutting guides, titanium
plates, and stents (Figs. 2.10, 2.11, 2.12).
Preoperatively planning the soft tissue for future
implant rehabilitation is as important as the bony
reconstruction. Predicting the future soft tissue
issues with implant rehabilitation will also guide
the approach. Often, skin paddles are not ideal
for the future implant interface. Considering fat
fascia paddles with bula free aps instead of
skin paddles, or lining the oral cavity with muscle instead of skin, allows for better mucosalization, making implant rehabilitation easier
(Fig.2.13).
As the technology continues to advance,
most of these options will be available in-house
31
Fig. 2.9 3D printed biomodel of a planned mandibulectomy and reconstruction with a bula. The plate was bent
and adapted on the biomodel
and will not depend on proprietary providers.
This will allow for more rapid turnover of
designs and will render this technology available to all patients being considered for bony
reconstructions [32].
32
hi
O. Breik and S. Parmar
a
d
b
e
c
f
g
Fig. 2.10 Case demonstrating the 3D computer-assisted
planning of a class III defect with a DCIA free ap with
prefabricated orbital oor reconstruction. (a, b) Showing
the area of resection and planned lateral cutting guide. (c)
DCIA planned and shaped to reconstruct the left maxilla.
(d) Cutting guide designed to harvest the iliac crest bone.
(e) A worm’s-eye view of a 3D computer-guided reformat
demonstrating the symmetry achieved by the DCIA
reconstruction. (f–i) Showing the clinical result of DCIA
reconstruction of the left side of the face after radiotherapy showing good facial symmetry and good
mucosalization
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