Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3706_Библиотеки_им_академика_М_И_Перельмана
.pdf
460
https://t.me/med1917
E. Shiah et al.
baric oxygen. The wound environment should be kept moist
in order to promote granulation, angiogenesis, extracellular
matrix remodeling, and robust cell proliferation from the
wound base to the surface (Table25.2).
While adjunctive therapies to wound dressings may
improve healing outcomes, the most important consideration
to any form of dressing is wound ofoading. Minimizing
both vertical and plantar shear stress will ensure the longevity of newly forming granulation and scar tissue. It can be
achieved through various means including reducing activity
and bed rest, therapeutic shoes with customized in-soles,
padded dressings, cushioned or half shoes, and total contact
casting (TCC) as the gold-standard. Choosing an ofoading
strategy must be tailored to the individual patient’s mobility,
Table 25.2 Adjuncts for secondary intention healing
Usage Success
Growth
factors
Cell-based materials Tissue replacement options include allografts,
Platelet- derived growth factor The only approved, isolated growth factor
treatment is becaplermin (Regranex, by
Johnson & Johnson), which is a recombinant
platelet- derived growth factor (PDGF). It
promotes chemotaxis and differentiation of
broblasts and smooth muscle cells,
stimulation of collagen production, and ECM
strengthening. It is applied as a topical gel in
varying concentrations
Fibroblast growth factor (FGF) FGF can be administered as a topical spray
and can be either basic FGF (bFGF), which
promotes angiogenesis, or acidic FGF (aFGF)
which promotes migration and proliferation of
broblasts
Epidermal growth factor (EGF) EGF can be administered topically as a gel
(Regen-D), topical cream (Actovegin), or
intralesional injection (Heberprot-P). EGF
broadly promotes skin healing and is primarily
expressed on keratinocytes
Granulocyte- colony stimulating
factor (GCSF)
Vascular endothelial growth
factor (VEGF)
G-CSF can be injected subcutaneously, to
enhance the immune response to wound
infection, or topically as a gel. G-CSF can
activate and enhance the function of
T-lymphocytes, dendritic cells, macrophages,
endothelial cells, and broblasts, among other
cell types
VEGF is available as a topical gel (Telbermin)
and is a key regulator of angiogenesis
such as Apligraf, which is a bilayered skin
equivalent consisting of a bovine matrix
populated by neonatal broblasts and
epithelial cells. Another dermal skin substitute
(Dermagraft) contains human broblasts on a
bioabsorbable scaffold. Other substitutes
include Grax, a human placental membranederived wound matrix, and TheraSkin, which
is a cadaveric combined dermal-epidermal
replacement
wound location and depth, and a patient’s willingness to
modify their lifestyle. Among all forms of off-loading, TCCs
or non-removable knee-high devices offer the most robust
support and reduction in healing times [37]. The primary
drawbacks of TCC include inability to assess the wound as
frequently, as well as secondary foot ulceration from a poorly
tting cast [38].
Successful wound healing by secondary intention may
include any combination of the adjunctive therapies listed in
Table25.2, along with adequate wound debridement, dressings, and maintenance. Key limitations of secondary intention are recurrence of infection if the wound is left open.
Wounds with exposed tendon or bone are more suited for
ap coverage.
Studies generally show success of PDGF
in expediting healing compared to
controls. Though not always measured,
wound size, optimization of glycemic
control, and adequate wound ofoading
determine its success
For the diabetic foot, topical FGF trends
towards shortening healing time. Results
have not shown statistical signicance,
except for application at high doses or
when combining bFGF with an articial
dermis
All studies have shown a signicant
improvement in healing outcomes and
decrease in healing time across all forms
of EGF.In fact, EGF may be most
successful in its application towards
diabetic foot ulcers, compared to other
forms of wound types
Results of injected G-CSF show mixed
signicance, with generally positive
results on resolution of cellulitis, reduction
of ulcer volume, and potentially fewer
amputation rates
One study showed a nonsignicant
reduction in healing time
All cellular matrices tested have shown
improved healing rates and faster healing
times compared to controls, though
cost-effectiveness and signicance of
outcomes are mixed
25 Reconstruction oftheDiabetic Foot
https://t.me/med1917
Table 25.2 (continued)
Usage Success
Acellular materials Like cellular matrices, acellular matrices
provide a matrix, typically composed of
collagen, oxidized regenerated cellulose, or
other extracellular components for
proliferating cells to inhabit
Oxygen therapy Oxygen can be applied either topically or by
hyperbaric therapy. Oxygen availability, which
is typically impaired in the setting of diabetic
foot ulcers, is critical for cell proliferation,
collagen synthesis, formation of granulation
tissue, and killing of bacteria. Particularly
useful for treating wounds with osteomyelitis
refractory to antibiotic therapy, hyperbaric
oxygen vastly increases the amount of dissolved
oxygen (and thus oxygen availability) in blood
to be delivered to healing tissue
461
Acellular matrices have consistently
shown to signicantly increase rates of
wound healing and expedite wound
healing times. One study has shown
acellular dermal matrices (ADM) with
NPWT to be successful in these settings,
once weight and pressure ofoading is
achieved
Topically delivered oxygen has shown
limited efcacy with some improvement
in healing rates and times. Hyperbaric
oxygen has been more widely used and
some studies have shown signicant
improvements in short term healing rates,
but its effectiveness in improving
long-term wound outcomes has not yet
been established
Delayed primary closure, sometimes called closure by
tertiary intention, involves waiting for a wound to show no
signs of infection (typically at least 48h) before completing
a closure with direct tissue approximation [39]. If prolonged
conservative wound care takes place, such as NPWT, there is
often loss of domain, skin retraction, and adherence, precluding the option of a simple closure.
Closure in layers from deep to supercial is preferred.
Liberal use of drains minimizes the risk of seroma formation. Precise dermoepidermal tissue apposition is critical.
Excessive undermining increases dead space and disrupts
vascularity.
Options to assist with delayed primary closure may also
be considered, such as the use of tissue expanders, vessel
loops, and other progressive tension closure methods.
Skin Grafts
Skin grafting is a simple coverage option and can be harvested as either a split-thickness or full-thickness graft.
Regardless of the type of graft, the wound bed must be adequate to allow for graft take/vascularization., adequate offloading, and optimization of vascular supply. Finally, the
patient’s nutritional status in accordance with glycemic control must be optimized [40].
Common donor sites for split grafts include the lateral or
medial thigh [41]. These options are suitable for non-weight
bearing regions of the foot (i.e., the dorsal aspect) or in-step
and are typically split-thickness grafts (STSG). For the
weight-bearing plantar side, which also possesses a thicker
glabrous layer, grafts harvested from the glabrous instep can
be considered but ap options are more likely to be indi-
cated. A thickness of 15/1000″ is commonly used. STSGs
despite having limitations in weight-bearing areas can drastically reduce the wound surface requiring ap coverage. In
the diabetic patient, STSGs have been shown to heal within
5weeks in 85.5% of patients [42]. NPWT is almost always
used pre and post grafting and improves graft survival to
93% [43].
NPWT can also be applied in full-thickness skin grafts
(FTSG). FTSGs, which include the full dermis layer, offer
more robust coverage, especially if glabrous skin is harvested. FTSGs require a more reliable blood supply to survive. Furthermore, the epidermis will often slough in the
initial postoperative period, making wound assessment more
challenging. Donor site breakdown is a signicant concern.
Local Flaps
Local aps are classied based on their vascular supply.
Random aps are those with blood supply that depends on
the subdermal plexus and not a specic artery. They often
include epidermis, dermis, and subcutaneous tissue, and
sometimes fascia and muscle. This makes them a good
option for the plantar surface of the foot due to their ability
to withstand shear forces [44, 45]. Axial aps are based on a
known artery that directly supplies a specic skin territory
[46]. Pedicled perforator aps are local aps based on specic musculocutaneous or septocutaneous perforators.
Common ap design options are summarized in
Table25.3. Advancement aps involve advancing the tissue
in one single direction with perfusion coming from the subdermal plexus and local perforators. In surgery of the foot,
these aps are often used to cover metatarsal head defects at
462
Pivot point
https://t.me/med1917
Table 25.3 Local ap design
Design Common uses
Rotation ap
E. Shiah et al.
Plantar surface of the foot where the ap is elevated
off the plantar fascia and rotated in position
Defect
Line of greatest tension
Transposition ap
Advancement ap
Lateral and medial malleoli or exposed tibial-talar
b
120°
a
60°
b
1
c
a
1
c
a
fusion
Plantar surface of the foot
b
c
25 Reconstruction oftheDiabetic Foot
https://t.me/med1917
463
the plantar or medial forefoot areas or the midfoot area [44,
Pedicled Flaps
47]. Rotation aps pivot around a xed point and are typi-
cally used to cover defects in the midfoot or hindfoot areas
[48–50]. Transposition aps combine the techniques of
advancement and rotational aps requiring less tissue mobilization; however, a skin graft is usually needed to cover the
donor defect (also called secondary defect). Transposition
aps are used to cover larger areas of the midfoot, hindfoot,
heel, and malleoli [47] (Table25.1, Fig.25.1).
Similar to local aps, pedicled aps are a suitable reconstructive option for small defects that have an unfavorable
recipient bed for skin grafting [45]. They require shorter
operative times compared to free aps while providing
appropriate coverage and aesthetic outcomes [45, 51].
Additionally, studies have found no statistically signicant
difference in complications (e.g., hematoma, wound dehis-
ab c
de f
Fig. 25.1 Advancement ap: Patient presenting with Charcot neuroarthropathy (a), after drainage revision surgery utilizing advancement
ap (b) with good outcome at follow-up visit (c). Rotational ap:
patient presenting with nonhealing wound (d) after debridement, a revision surgery with a single fasciocutaneous rotation ap based on the
medial plantar artery ap (e) with a good outcome at follow-up visit (f).
Transposition ap: patient who presented with gas gangrene and
osteomyelitis of the right hallux (g), after amputation of the hallux and
debridement, single transposition ap harvested dorsally with plantar
tissue was advanced to cover the rst metatarsal site, the donor site was
covered with a bilayer meshed collagen acellular dermal replacement
(h) with good healing post-operatively (i). This gure is quoted from
Patel [46] published in Local Random Flaps for the Diabetic Foot by
Elsevier, copyright 2022. Reprinted with permission from Elsevier
464
hi
https://t.me/med1917
g
Fig. 25.1 (continued)
E. Shiah et al.
cence, infection, partial or full ap necrosis) and a slightly
higher success rate for limb reconstruction with pedicled
aps compared to free aps [51].
Muscle Flaps
Lower Leg and Ankle: In the lower leg and ankle, only a
small portion of the muscle can safely be transferred in a
muscle ap as most of the lower leg muscles are a type IV
muscle (Mathes and Nahai classication) with segmental
minor pedicles (the exception being the soleus muscle).
These aps are most useful for reconstructing small defects
of the lower leg and ankle. For example, aps fashioned from
the extensor hallicus longus, extensor digitorum longus, or
peroneus tertius muscles, all of which are based on the anterior tibial artery, can be used to reconstruct small (typically
<3 × 6 cm) anteromedial ankle defects. From the anterior
portion of the leg, the anterior tibialis muscle ap can be
designed to cover linear anterior defects by itself or in conjunction with a soleus ap to cover larger, longitudinal
defects of the middle-third and distal-third of the leg. Given
its role as chief dorsiexor of the foot and its segmental
blood supply, transposition of the entire anterior tibialis muscle is not recommended [52]. However, distal portions of the
muscle can be used to cover defects up to 6–8cm in size
[53]. The peroneus brevis muscle supplied by the peroneal
artery can also be used as it is expendable, without signicant functional decit. It can be harvested in a proximal or
distal-based fashion, allowing reconstruction of small to
moderately sized defects in the anterolateral distal leg and
ankle [54]. Finally, the soleus can be used in the distal lower
leg. As the only type II muscle in this region, its blood supply
comes from branches of the popliteal artery (proximally), the
posterior tibial artery (medially), and the peroneal artery (laterally). The minor distal pedicles can be divided, leaving
only the proximal pedicles intact so that the muscle ap can
be rotated into place for larger or more anterior defects of the
distal leg. It can be harvested as a hemi-soleus for smaller
defects [55].
Foot: In contrast to the lower leg, muscles in the foot are
slightly more reliable candidates for pedicled aps due to a
type II blood supply with a dominant pedicle and several
distal minor pedicles. Based on the lateral plantar artery,
both the abductor digiti minimi (ADM) and exor digitorum brevis (FDB) muscle aps can be used to cover defects
of the plantar heel. The ADM ap can also be utilized for
coverage for calcaneal osteomyelitis, lateral malleolar
defects, and even midfoot reconstruction; detachment of
the muscle origins on the lateral calcaneus may increase
mobilization to cover further defects, such as the midfoot
[56]. In contrast to the small arc of the ADM ap, the FDB
can be pivoted to reach defects of the Achilles tendon. Its
best utility is with deep defects that can be covered primarily with local glabrous skin [56]. Defects of the lateral malleolus and lateral calcaneus can also be reconstructed with
an extensor digitorum brevis ap based on the lateral tarsal
artery. Harvesting the ap on the dorsalis pedis artery can
widen the arc of rotation [57]. Finally, the abductor hallucis
muscle ap, supplied by the medial plantar artery, can harvested to cover defects of the plantar heel, medial heel, and
medial ankle. For large midfoot and plantar heel defects,
combining abductor hallucis and abductor digiti minimi
aps can be helpful.
25 Reconstruction oftheDiabetic Foot
https://t.me/med1917
465
Fasciocutaneous Flaps
Certain regions of the foot and ankle, such as the midfoot or
forefoot, benet from thinner and more pliable ap options
to meet both functional and aesthetic needs [58].
Fasciocutaneous aps are a suitable reconstructive option for
such areas. Recently, perforator-based designs have gained
popularity as they have a greater arc of motion, such as the
propeller ap [59].
Lower Leg and Ankle: Two aps based on retrograde ow,
the retrograde sural ap and the retrograde anterior tibial
ap, are suitable approaches to lower leg reconstruction with
fasciocutaneous aps [57, 60]. The retrograde sural ap
receives retrograde arterial ow through septocutaneous perforators originating from the peroneal artery that directly
anastomose with the median supercial sural artery. These
perforators are located about 4–7cm above the lateral malleolus. The sural nerve and lesser saphenous vein are important landmarks during dissection, and the ap may be
harvested as a neurocutaneous ap. The retrograde sural ap
is a versatile ap that can be used to reconstruct defects of
the anterior distal leg and calcaneus, as well as the posterior
heel, lateral and medial malleolus, and dorsal surface of the
foot [60]. The retrograde anterior tibial ap which receives
blood supply via retrograde ow from the anterior tibial
artery can also be used to reconstruct defects of the anterior
lower leg and dorsal surface of the foot. Since the tibialis
anterior plays such a major role in foot dorsiexion, only the
lower half of the artery can be safely harvested for the ap,
limiting its range. The lateral supramalleolar ap based on a
perforator of the peroneal artery is another suitable option
for defects of the lateral malleolus and anterior ankle,
although the retrograde sural ap appears to have a slightly
higher success rate in these areas [61]. Finally, propeller
aps based on perforators of the posterior tibial artery or
peroneal artery can be used for defects of the malleoli.
Foot: In the foot, the medial plantar ap supplied by the
medial plantar artery provides ideal tissue for the coverage of
plantar and medial ankle defects. It is particularly suitable
for reconstruction of heel defects as it offers matching glabrous tissue. The medial plantar nerve may be harvested to
provide a sensate heel ap. The arterial supply to the lateral
calcaneal ap is the calcaneal branch of the peroneal artery;
this ap is useful for the reconstruction of defects of the
Achilles tendon, posterior heel, and lateral malleolus [62,
63]. The length of this ap can be increased by harvesting it
as an “L” shape posterior to and below the lateral malleolus.
For defects of the dorsum of the foot, a dorsalis pedis ap
can be utilized; however, it is important to keep in mind that
the distal ends of a larger proximally based ap may be vulnerable to fail due to anatomic variations of the rst dorsal
metatarsal artery [52, 64]. As in the lower leg, propeller aps
can also be fashioned for soft tissue reconstruction of the
foot. Based on the perforators, propeller aps may be used
for plantar forefoot defects (medial plantar artery) or calcaneal defects (branches of the peroneal artery) [65]. For distal
forefoot defects, a let toe ap supplied by the digital artery
can be utilized for small forefoot web space ulcers and distal
forefoot defects. Standard let toe aps involve isolating and
leaving two digital arteries while removing nail bed, phalangeal bones, tendons, and volar plates (Fig.25.2).
Free Flap Reconstruction
As the eld of microsurgery continues to evolve, free ap
reconstruction for lower extremity defects has become more
commonplace [66]. Earlier free ap reconstruction is advocated in traumatic injuries [67–69]. In diabetic foot reconstruction, free tissue transfer is delayed until the wound bed is
clean, nutrition and glycemic control are optimized, and the
patient is medically safe to undergo a prolonged anesthetic.
Options include muscle, fasciocutaneous, and skin-only
free aps. Muscle aps are often used for larger soft tissue
defects that benet from obliteration of dead space as well as
cases that have an irregularly shaped wound bed, such as
near-circumferential defects. Their supposed superior vascularity was initially speculated to lower infection rates by
allowing for improved bacterial clearance and antibiotic
delivery. However, more recent studies have identied no
statistically signicant differences compared to fasciocutaneous aps [70–73]. While muscle aps are generally more
straightforward to raise, they result in greater donor site morbidity and also necessitate a skin graft. Fasciocutaneous aps
are easier to monitor post-operatively for viability and are
better suited for shallow defects, such as in the distal third of
the leg and around the ankle.
Muscle Free Flaps
For muscle ap selection, it is critical to consider the degree
of functional loss after free tissue transfer. The latissimus
dorsi free ap based off the thoracodorsal artery can be an
attractive option to provide bulk for larger tissue defects and
can also be harvested with a skin paddle. Shoulder strength
however commonly does not recover fully and some patients
could experience persistent limitation on activities of daily
living, especially those who are crutch or wheelchair dependent [74, 75]. It is also commonly too bulky for the foot and
ankle where good shoe t is critical for quality of life,
although in most cases, these aps are expected to thin out
over time. Similarly, the free vastus lateralis ap is useful to
provide bulk but with potential concerns for quadriceps
weakness and knee instability [76]. Regardless, muscle aps
generally have limited variable perforator anatomy resulting
expedient dissection.
466
https://t.me/med1917
E. Shiah et al.
Fig. 25.2 Fillet of great toe to cover medial foot defect with exposed bone in an immunosuppressed patient. A small, non-weightbearing area was
covered with a dermal substitute which eventually reepithelialized without further intervention
The gracilis free ap on the other hand offers minimal
donor site morbidity and loss of function. Harvest time of the
ap and its branches off the medial femoral circumex vessels can parallel that of a pedicled ap with an overall high
success rate [75, 77, 78]. In cases of unfavorable vascular
anatomy encountered intraoperatively, the same incision site
can be converted to an adductor magnus free ap dissection
[79]. Disadvantages of the free gracilis ap include its relatively short pedicle length, small vessel caliber, and its limited size, although signicant size variability is often
encountered. Preoperative ultrasound imaging can provide a
useful size estimate (Fig.25.3).
25 Reconstruction oftheDiabetic Foot
https://t.me/med1917
467
The parascapular free ap is supplied by branches of the
circumex scapular artery and is another useful ap, with a
thick dermal layer [87]. It can provide a large ap territory
while allowing for primary closure of the donor site [88]. Its
vascular anatomy allows it to be harvested as a so-called chimeric ap, with scapular bone and latissimus muscle for
composite tissue defects requiring multiple different tissue
types.
The radial forearm and lateral arm free aps can both be
used for small to medium sized defects. As thin and pliable
aps, they are particularly useful for allowing gliding such as
tendon coverage as well as conforming to irregular contours
of the foot and ankle [89]. The lateral arm ap is based on
perforators from the posterior radial collateral artery and its
donor site can be closed primarily. However, vessel caliber is
small and pedicle length is short [90]. The radial forearm ap
is an option for cases needing limb revascularization as it can
be designed as a ow-through ap using the radial artery [91].
The main disadvantage is a conspicuous donor site typically
requiring skin graft for closure and sacrice of a major artery
to the hand which is less than ideal in the vasculopath [92].
The Supercial Circumex Iliac Artery Perforator ap
(SCIP), harvested from the groin region, offers an inconspicuous donor site and can be harvested as a thin ap in
most patients, even if obese. Downsides are its variable
vascular anatomy, short pedicle length, and smaller vessel
caliber. Preoperative ultrasound makes dissection expedient and safe [93].
Fig. 25.3 Unusually large gracilis ap encountered in a middle-aged
diabetic patient that underwent free tissue transfer to reconstruct a plantar soft tissue defect. Due to recurrent breakdown, he eventually underwent below the knee amputation 3 years later. No signs of muscle
atrophy of the denervated, transferred gracilis muscle were noted at the
time of the amputation, contrary to traditional teaching
The serratus anterior and rectus abdominis muscle aps
have many advantages for reconstruction in the foot and
ankle with exposed nerve, tendon, and bone given their low
prole. The serratus anterior has a long pedicle, allowing for
more distant/proximal anastomosis [80, 81].
Cutaneous andFasciocutaneous Free Flaps
Free cutaneous and fasciocutaneous aps have become
increasingly popular and are associated with lesser donor site
morbidity and improved cosmetic outcomes. The most popular fasciocutaneous ap in lower extremity reconstruction is
the anterolateral thigh free ap for its high reliability and versatility [82–84]. The ability to harvest a large skin paddle and
long pedicle and adjust its thickness and volume based on
requirements of the defect makes it a workhorse in lower
extremity reconstruction [85]. It can also be congured as a
ow-through ap to revascularize portions of the foot, and
even neurotized to provide protective sensation [86].
Free Flap Principles andApproach
The overall success rate of free tissue transfer to the lower
extremity is signicantly lower than to other parts of the
body such as the breast or head and neck, likely due to
compounding risk factors [94, 95]. For the diabetic foot,
patients frequently have secondary conditions including
extremity edema, uncontrolled diabetes, and peripheral vascular disease [96]. Pre-operative optimization with diuresis,
glycemic control, and evaluation by a vascular surgeon is
required. Screening for hypercoagulable state with appropriate hematological evaluation and anticoagulation therapy is
critical for patients with a history of recurrent thrombosis.
After free ap selection based on soft-tissue requirement,
length of pedicle, size of ap, and donor-site morbidity, considerations should be made for recipient vessel selection. An
adequate size and quality of the vein is imperative to minimize risk of venous ap compromise. This can be assessed
with venous mapping or magnetic resonance venogram,
especially when there is prior injury/surgery or history of
deep venous thrombosis. For recipient artery assessment,
formal arteriograms, computed tomography angiography in
conjunction with hand-held Doppler ultrasound are commonly used, with MR angiography, duplex ultrasonography,
and indocyanine green uorescence angiography as emerging alternatives [97, 98].
468
https://t.me/med1917
E. Shiah et al.
There remains no clear data on outcome differences
between end-to-end or end-to-side arterial anastomosis
[99, 100]. However, end-to-end anastomosis is considered
technically easier to perform while end-to-side technique
preserves distal perfusion. Arterial anastomosis is routinely performed using 9-0 to 11-0 sized sutures in the
lower extremity using an operating microscope. For venous
anastomosis, using a coupler device has gained popularity
for its ease and expediency, with patency rates equivalent
to a hand- sewn anastomosis [101].
The key elements in post-operative care involve close free
ap monitoring and often a lower extremity dangling protocol to gradually increase tolerance to increasing venous pressures. Although the use of blood thinning agents has not been
shown to signicantly reduce incidence of vessel thrombosis, aspirin and heparin are commonly administered in the
peri-operative setting [102, 103]. Clinical assessment includ-
ing the use of a handheld Doppler remains the gold standard
for free ap monitoring, although many advanced techniques
such as tissue oximetry, surface temperature monitoring, and
implantable Doppler have been employed [104]. Most centers employ a dangle protocol and compression, although
much variability exists [105, 106].
While the immediate focus of free tissue transfer in lower
extremity reconstruction is ap survival, ap bulkiness and
contour become important to address from a functional
standpoint. Flaps are ideally harvested as thin as possible for
use in the foot and ankle, but can be thinned secondarily.
Reconstruction by Location ofDefect
Reconstruction oftheForefoot
The forefoot is one of the most common sites of diabetic foot
ulcers (about 70%) due to its highly functional, weightbearing role. Forefoot ulcers occur in any location from the
toes to the metatarsal heads.
Toe defects are often addressed with local wound care,
limited debridements, and amputations. Adjunct procedures
to address deformities such as hammer and claw toes and
hallux deformities are often required to redistribute pressure
and allow ulcers to heal [107, 108].
Metatarsal Heads
The aforementioned deformities, including hammer/claw
toe, hallux valgus, hallux limitus, lesser toe arthropathies,
and any sort of soft tissue atrophy, may precipitate ulceration
at the metatarsal head [109, 110]. Beyond these factors, the
most signicant driver of ulceration in this anatomic area is
poor mobility of the Achilles tendon causing impaired dorsi-
exion (pes equinus) [111]. This is highly prevalent, with
almost 89% of patients with diabetes having altered tendon
collagen bril morphology [112]. This can be addressed by
Achilles tendon lengthening or gastrocnemius recession. If
amputations become necessary, llet aps can be used to
cover the exposed metatarsal heads. Otherwise, local aps
such as rotation-advancement aps taken from the glabrous
surface can provide stable coverage.
Reconstruction oftheMidfoot
Primary defects of the midfoot are relatively rare and are
usually found on the plantar surface. An advantage of this
location is that there is more soft tissue between the skin and
deep structures than in the forefoot. On the lateral surface of
the midfoot, the peroneus longus tendon that courses around
the promontory of the cuboid is important to identify because
infection can spread here. On the medial surface, the tissue
loss is usually in proximity to the abductor hallucis muscle
which is important to preserve if at all possible.
Ulcers on the plantar midfoot are typically due to Charcot
collapse of the midfoot plantar arch. Excisional debridement
and surgical resection in the midfoot often result in a larger
soft tissue decit precluding simple closure [113]. When primary or delayed wound closure are not possible, splitthickness grafts can be employed although they are typically
not used on weight-bearing surface. Local aps, pedicled
aps, and free aps are considered. For small defects, local
aps such as a rotation, bilobed, rhomboid, V-Y, or transposition aps can be used. If a muscle ap is desired, a pedicled
abductor hallucis ap medially or an abductor digiti minimi
ap can be considered. For larger defects, V–Y aps and
medially based rotation aps or pedicled, islandized medial
plantar fasciocutaneous aps have been successfully used. If
the defect is larger, then free aps are considered.
Reconstruction oftheHindfoot
The hindfoot encompasses the bony prominences of the calcaneus, lateral malleolus, and medial malleolus, which can
lead to ulceration secondary to pressure. These decubitus
ulcers are difcult to treat with conservative measures
because of the underlying bony prominence and often associated vascular disease. The most common site is the posterolateral aspect of the heel and is addressed with a partial
calcanectomy and local closure. Flap coverage can be
required, as well as an external xator to ofoad the foot
until the wound has healed. Free aps are elegant alternatives
and can have very limited morbidity (Fig.25.4).
25 Reconstruction oftheDiabetic Foot
https://t.me/med1917
469
Fig. 25.4 Reconstruction of a lateral hindfoot defect on the non-glabrous surface secondary to calcaneal osteomyelitis. A free SCIP (supercial
circumex iliac artery perforator) ap was utilized and plugged into the lateral calcaneal vessels end-to-end
Reconstruction oftheDorsum
require split thickness skin grafts to the donor site [116]. The
most suitable free aps for the dorsum of the foot are thin
Soft tissue reconstruction of the dorsum of the foot requires
thin coverage [58] For a well vascularized wound bed, split
thickness skin grafts are ideal. In the case of signicant
extensor tendon or bone exposure, a skin substitute can be
placed and eventually grafted. Pedicled ap options include
fasciocutaneous free aps such as the radial forearm, as well
as thin muscle aps such as the serratus [58] (Fig. 25.5).
Fascial aps such as the temporoparietal ap are not commonly used but offer excellent contour and a glide layer for
underlying tendons.
the extensor digitorum brevis which is broad, at muscle ap
ideal for reconstructing defects of the anterior ankle and
proximal dorsal foot [114, 115]. The reach of the ap can be
Reconstruction oftheAnkle
increased by dividing the dorsalis pedis artery above or
below the tarsal vessel. The dorsalis pedis ap is thin and
malleable to the recipient site without providing unnecessary
bulk. The lateral supramalleolar ap offers similar benet for
coverage of the anterior and lateral aspects of the dorsum of
the foot. The drawback of these aps is that they can often
In the ankle, achieving thin yet stable soft tissue coverage
allows for appropriate shoe wear and motion of the joint
[58]. Skin grafts are therefore ideal in this location (Fig.25.6).
In preparation, skin substitutes can promote formation of a
suitable wound bed.
Соседние файлы в папке Библиотека им академика М.И. Перельмана