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Dorsal Metacarpal Artery Flaps
PrateushSingh, AndreasGeorgiou, JuliaRuston,
andDariushNikkhah
26
26.1 Introduction
Dorsal metacarpal artery aps are vascularized skin aps
from the dorsum of the hand, based on either the rst to the
fourth dorsal metacarpal arteries or their perforators.
Multiple variations have been described, differing based on
their location, pedicle, and anterograde or reverse ow. In
general, they provide a thin, pliable ap suitable for reconstruction of dorsal defects of the hand and digits (up to and
even beyond the PIPJ), as well as the webspace and the
thumb. Although the aps can reach volar defects of proximal digits, they are not ideal, being non-glabrous and less of
a color match than volar skin.
The rst dorsal metacarpal artery (FDMA) ap is an
anterograde neurovascular island ap, where robust skin
from the dorsum of the proximal index nger is transferred
to the thumb. It was initially described by Foucher and Braun
in 1979 [1], with terminal branches of the radial nerve to
provide sensation to the ap. Various techniques of elevation
of the FDMA ap have been described, the Holevich technique gives the ap a tennis racquet form, and the skin island
over the pedicle is smaller [2]. The FDMA ap is indicated
in volar or dorsal thumb defects. It should be used with caution when resurfacing thumb pulp defects, as it may not
reach the most distal thumb tip without resultant IPJ exion
and it does not provide glabrous tissue.
Quaba and Maruyama both described the reverse dorsal
metacarpal artery (DMCA) aps utilizing skin overlying the
intermetacarpal space to reconstruct the webspace or the
dorsum of digits, up to the proximal interphalangeal joint
(PIPJ) [3, 4]. The Maruyama ap incorporates the main
DMCA, while the Quaba ap is based on a DMCA perfora-
P. Singh · A. Georgiou · J. Ruston · D. Nikkhah (*)
Royal Free Hospital, London, UK
tor, which occurs just distal to the juncturae tendinae, and
facilitates a slightly longer arc of rotation. Modications
based on the more dorsal communicating perforators of the
common digital artery allow a more distally based pivot
point and thus reconstruction of dorsal digital defects
beyond the PIPJ.The primary indications described for the
Quaba ap include reconstruction of webspace, dorsal
metacarpal, dorsal phalangeal skin, and distal palmar defects
[4]. Maruyama describes similar uses to reconstruct small
soft tissue defects in the hand; however as the main DMCA
is incorporated, the reach of this ap can extend beyond the
PIPJ [3].
26.2 Anatomy
The dorsal metacarpal arteries run over the dorsal interosseous muscles to supply the skin and soft tissue over the dorsum of the hand and digits. Dorsal branches of the radial and
ulnar arteries form the dorsal carpal arch, and from this the
dorsal metacarpal arteries arise. The FDMA arises usually
from the dorsal radial artery itself, and the second to fourth
DMCA may also exhibit variations, such as arising direct
from the radial artery or from adjacent metacarpal arteries.
The fth DMCA often arises direct from the ulnar artery.
The anatomy can become less predictable toward the ulnar
side (fourth and fth metacarpal arteries may be completely
absent). Each DMCA communicates with the deep palmar
arch through intermetacarpal connections. Cutaneous perforators arise along the length of the DMCA.The perforator
upon which the Quaba ap is based is around 1cm proximal
to the corresponding metacarpophalangeal joint (MCPJ) or
1.5cm proximal to the leading edge of the interdigital web.
With each DMCA there are two venae comitantes (0.2–
0.3 mm diameter) which provide venous drainage for the
aps. Quaba etal. found on dissections of 18 cadaveric specimens that in the distal third, there was a consistent leash of
blood vessels, however a paucity of vascular connections in
© Springer Nature Switzerland AG 2023
D. Nikkhah et al. (eds.), Core Techniques in Flap Reconstructive Microsurgery, https://doi.org/10.1007/978-3-031-07678-7_26
249
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the proximal two-thirds. The perforating vessels were seen
entering the skin 0.5–1cm proximal to the MCPJ.This pattern was found to be less consistent on the radial and ulnar
border of the hand, but reliable between the second and
fourth metacarpals [4].
The FDMA gives branches to the thumb and rst webspace and terminates as the external dorsal artery of the index
nger, supplying the skin over the dorsum of the index nger’s proximal phalanx. The FDMA anatomy is relatively
constant, with a diameter up to 1 mm and few collateral
branches. Two dorsal veins run supercially to the artery
alongside radial nerve branches [1]. In a study by Magdi
Sherif in 21 cadaveric hands, they found 3 patterns of division
of the FDMA [5]. It constantly gave three fascial branches: a
radial branch, an ulnar branch, and an intermediate branch. A
cutaneous branch was also observed, which may arise either
from the radial artery or from the FDMA. It runs with the
radial nerve supplying dorsal hand skin. This branch may
supplement the vascularization of FDMA ap. Due to variation in the division pattern of the FDMA, it is safer to raise the
whole rst DIO fascia in the pedicle of the ap. This preserves the three branches of the artery without the dissection
of FDMA or exposure of the artery of its origin.
The fourth DMCA does not reliably give off cutaneous
perforators; however it consistently has a distal recurrent
branch running supercial to the extensor digitorum communis tendon to the little nger, upon which aps can be
based [4].
Composite aps for functional reconstruction include the
incorporation of extensor tendon for tendon defects, which
are not uncommon in cases of dorsal digital skin loss.
Neurotized DMCA aps can incorporate the dorsal cutaneous branches of the radial and ulnar nerves which run across
the dorsum of the hand.
The arrangement of the DMCA and its cutaneous perforators are demonstrated in Fig.26.1. The rst diagram demonstrates the normal anatomy. The second diagram is a ap
raised on the distal most cutaneous perforator of the
DMCA.In the last diagram, the ap is raised on the main
DMCA and its perforators (Fig.26.1).
26.3 Preoperative Investigation
A preoperative handheld Doppler ultrasound can be used to
identify the position of the perforators and to delineate the
FDMA pedicle. This is especially useful where the anatomy
is less consistent, toward the ulnar digits. Further imaging is
not required.
P. Singh et al.
Fig. 26.1 Reverse Island DMCA ap based on single perforator
(Quaba) or encorporating entire DMCA (Maruyama)
26.4 Flap Design andMarkings
FDMA markings for thumb tip defect after Squamous Cell
Carcinoma excision (Fig.26.2).
The excision margins of the neoplasm on the thumb are
marked, and this intended defect is used to template the
required ap size over the proximal phalanx of the index nger (from MCPJ proximally to PIPJ distally and as wide as
the mid-lateral lines if necessary). The FDMA is identied
with handheld Doppler and marked. A curvilinear skin incision is marked over the pedicle.
Quaba ap markings for a defect on the dorsum of the left
ring nger (Fig.26.3).
The third webspace perforator is identied with Doppler
and marked with a dot. This is the pivot point around which
the ap will be rotated. The proximal tip of the marked ap
should be the same distance from the perforator, as the distance to the distal defect edge. The maximum ap width is
determined by the pinch test, to assess laxity for primary
closure. The shaded area on the ap in this example illustrates where the skin will be de-epithelialized to go under
the skin bridge at the recipient site (this is not usually
required).
26 Dorsal Metacarpal Artery Flaps
251
Fig. 26.2 The FDMA ap marked on the index
Fig. 26.3 Reverse DMCA Flap markings on the dorsum of the Left
Ring Finger
26.5 Flap Raise/Elevation: AStep-by-Step
DMCA aps are raised using a size 15 blade under loupe
magnication (2.5x), under tourniquet control without
exsanguination (so the vessels are still visible).
26.5.1 FDMA Flap (Foucher Flap)
• Flap Raising.
(a) Skin is incised over the pedicle (curvilinear) and skin
aps raised in the subdermal plane (to preserve
underlying veins) and reected (Fig.26.4).
(b) The ap itself is then raised from distal to proximal
(Fig.26.5). The skin paddle is raised in a plane supercial to the paratenon. Care must be taken at the
MCPJ not to injure the FDMA or cutaneous branches
Fig. 26.4 Skin aps are raised in a the subdermal plane
Fig. 26.5 Flap raised from distal to proximal under tourniquet control
without exsanguination. Adson forceps demonstrating FDMA pedicle
at the base of the ap
that supply the skin island. We incorporate a small
cutaneous tail to the skin island to avoid injury to the
pedicle at the MCPJ (Fig.26.6).Then upon reaching
the insertion of the rst dorsal interosseous muscle,
the plane of dissection deepens to incorporating the
entire epimysium and fascia of the rst dorsal interosseous muscle with the FDMA pedicle. A wide cuff
of adipofascial tissues over the rst dorsal interosseous with additional veins are taken.
(c) No attempt is made to skeletonize or visualize the
main FDMA pedicle until the end of ap elevation
(Fig.26.5).
(d) The proximal extent of pedicle dissection depends on
required ap reach. The muscle branches will bleed
and can be coagulated with bipolar diathermy.
• Flap Inset (Fig.26.7).
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P. Singh et al.
Fig. 26.6 Care must be taken at the MCPJ not to injure the FDMA or
cutaneous branches that supply the skin island
Fig. 26.7 Flap tunnelled and inset to cover dorsal thumb defect. Full
thickness skin graft used to cover the donor site
(a) The ap is tunneled under the skin and inset to cover
the recipient site. Vascular congestion can be minimized in ap inset in volar defects by dividing the
skin and avoiding tunneling.
(b) A full- thickness skin graft is used to resurface the
donor site.
• Outcome (Fig.26.8).
Fig. 26.8 Long term follow up of patient with FDMA ap to reconstruct dorsal thumb defect post SCC excision
(a) The patient had an excellent outcome with full func-
tion of the hand; the result is shown at 12months.
26.5.2 Reverse Dorsal Metacarpal Flap.
Fig. 26.9 Reverse dorsal metacarpal artery ap raised from proximal
to distal. The tenotomies demonstrate the encorporation of an extra dorsal vein to reduce congestion
a plane supercial to the paratenon. The dissection
continues until the junctura is reached, as the perfora-
1. Flap Raising (Fig.26.9)
(a) The reverse dorsal metacarpal artery ap is raised
tor is just distal to this and should not be
skeletonized.
here on the third DMCA.Raising starts proximally in
26 Dorsal Metacarpal Artery Flaps
253
Fig. 26.10 Reverse DMCA ap raised on the 3rd DMCA perforator
Fig. 26.11 DMCA perforator approached through a retrograde dissec-
tion after resection of a squamous cell carcinoma (SCC) in the
webspace
(b) The distal tip of the ap is raised, with careful dis-
section around the perforator (Figs. 26.10 and
26.11). An adipofascial cuff around the perforator is
preserved, to maintain venous drainage. Dorsal veins
are also included in the ap to reduce venous con-
Fig. 26.12 Flap propelled through 180 degrees
Fig. 26.13 3rd reverse DMCA ap inset to dorsal phalangeal skin
defect
gestion (Fig.26.9). Quaba also described a modication of this ap being raised with a “vascularized”
tendon graft, which can be used to bridge an extensor gap.
(c) The ap is propelled through 180 degrees and the
areas corresponding to the skin bridge deepithelialized (Fig.26.12).
1. Flap Inset (Fig.26.13).
(a) Here the tip of the ap has been tunneled to the distal
defect (Fig.26.8). In the majority of cases, the ap is
simply rotated into the defect and inset, with primary
closure of the donor site.
2. Outcome (Fig.26.14).
(a) The patient is shown here at 3-month follow- up with
full range of motion (Fig.26.15).
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Fig. 26.14 3-month Follow-up
Fig. 26.15 Demonstration of full exion after DMCA ap reconstruc-
tion over MCPJ
26.6 Core Surgical Techniques inFlap
Dissection
P. Singh et al.
26.7 FDMA Flap
1. The donor site is marked out: the dorsum of the proximal
phalanx of the index nger, with the artery delineated
using a pencil Doppler ultrasound.
2. The borders of the ap are incised– this is down to the
paratenon laterally and distally, but at the proximal edge
just through the dermis, down to the adipofascial layer.
The skin aps overlying the pedicle are raised thin, in the
subdermal plane.
3. The FDMA ap is raised distal to proximal, with dissection initially supercial to the paratenon. Care must be
taken when dissecting at the MCPJ not to injure the
FDMA or cutaneous branches that supply the skin island.
4. At the level of the dorsal interosseous muscle, dissection
becomes deeper, just above the muscle, to incorporate the
FDMA (which runs in the epimysium). The width of the
adipofascial tissue raised can extend to the second metacarpal and should incorporate dorsal veins to minimize
venous congestion. This dissection is continued
proximally to achieve as much length as is required.
Branches running into the muscle can be ligated with
microligaclips or coagulated. It is important to not skeletonize the vessel; it is often visualized at the end of dissection and can be transilluminated through the
adipofascial tissues.
5. For dorsal defects, a subcutaneous tunnel is made,
through which the ap is passed with the help of a silk
suture. For volar defects, tunneling risks constriction of
the pedicle so make an incision along the direction the
ap must travel.
6. A neurotized FDMA ap, incorporating a branch of the
SBRN, is particularly useful for sensate reconstruction of
volar thumb defects. Two-point discrimination of 10mm
can be achieved.
7. A full-thickness skin graft is used to resurface the donor
defect on the index nger (hence the importance of preserving paratenon). If any of the ap pedicle is exposed
and cannot be covered without excessive compression,
the pedicle can also be grafted. The skin aps overlying
the FDMA pedicle donor site are closed primarily.
26.7.1 Reverse Dorsal Metacarpal Artery
Perforator (Quaba) Flap.
The aps are raised under tourniquet control but without
exsanguination to allow direct visualization of the vessels.
1. For the Quaba ap, a pivot point is planned in the distal
third of the intermetacarpal space and the perforator iden-
26 Dorsal Metacarpal Artery Flaps
255
tied with handheld Doppler. The defect is templated and
used to design the ap, extending proximally over the
intermetacarpal space and based around the pivot point.
2. The ap is raised proximal to distal, preserving paratenon
of the extensor tendons, until the distal edge of the junctura is reached.
Alternatively, the ap can also be raised retrograde as
anatomical studies have shown that skin perforators arising from the palmar metacarpal artery are often consistent; therefore, the retrograde approach is based on the
connection between the dorsal metacarpal artery (DMA)
and the palmar arterial system at the level of the metacarpal head. A retrograde approach involves identifying the
most distal perforator rst from the palmar source vessel,
starting the dissection in the webspace [6].
The variable anatomy of the third to fth dorsal metacarpal arteries sometimes prevents successful ap harvest
[4].
3. The perforator is not skeletonized and a cuff of adipofascial tissue around it is preserved.
4. The ap is rotated into the defect and tourniquet released
to assess perfusion and check there is no kinking or restriction at the rotation point. Further (cautious) dissection
around the perforator may be needed to avoid tension.
5. The ap is inset, the ap often becomes hyperemic, and
surgeons can dissect and include a dorsal vein which may
help to avoid ap congestion.
6. The donor site can be closed directly.
26.8 Clinical Scenario
26.8.1 Case Scenario A: Figs. 26.2, 26.4, 26.5,
26.6, 26.7, and 26.8
Surgeon Dariush Nikkhah
• A 65- year- old carer developed a squamous cell carci-
noma (SCC) of the dorsum of her thumb nail bed complex. Biopsy conrmed a poorly differentiated SCC, and
after multidisciplinary team discussion, decision was
made to perform a wider excision and post operative
radiotherapy. The patient had excision of the SCC and
entire nail bed complex down to bone, and a FDMA ap
was raised to resurface the defect. At 1year the patient
remained disease- free and had full function of the hand
with an excellent donor site outcome.
26.8.2 Case Scenario B: Figs. 26.3, 26.10, 26.12,
26.13, 26.14, and 26.15
Surgeon Dariush Nikkhah
• A 55- year- old patient suffered a traumatic loss of soft
tissue above the extensor tendon of her ring nger with an
exposed MCPJ.A reverse dorsal metacarpal artery ap
was designed to reconstruct the defect. The patient made
a full recovery and as demonstrated at 3months had no
exion or extension decit in the hand.
26.9 Pearls andPitfalls
Pearls
Tips for FDMA Flaps
• Raising thin skin aps over the FDMA allows preservation of veins within the adipofascial tissue of
the pedicle.
• Taking all the first dorsal interosseous fascia and
dorsal epimysium, and not skeletonizing the
pedicle, allows safe flap elevation. It also protects the venae comitantes from unnecessary
trauma.
• A distal dorsal branch of the radial nerve can be
incorporated to neurotize the ap.
• Dorsal defects may not need a subcutaneous tunnel
for the ap, but palmar defects may necessitate
one.
• A cutaneous tail can be incorporated, extending
proximally from the ap over the FDMA pedicle.
This can maintain small cutaneous vessels and
reduce tension when closing skin over the pedicle,
in cases where the ap is not tunneled (or if the tunnel will be too tight).
Tips for Reverse DMCA Flaps
• Be careful in the vicinity of the perforator– careful
dissection is needed to release tethering brous
bands without skeletonizing the vessels. This allows
rotation without constriction of the perforator and
veins.
• More radial Quaba aps are more reliable.
• It is possible to incorporate tendon with DMCA
aps.
• The Quaba ap is a good option for webspace
defects where retrograde dissection can identify
vessels on which to base the Quaba or extended
Quaba ap (Fig.26.16).
• The ap can be based on a more distal perforator to
increase the ap reach– the perforator is level with
the distal webspace, and the perfusion is via the rst
dorsal branch of the palmar digital artery. Extended
aps can reach palmar defects and even to the level
of the DIPJ.
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Fig. 26.16 1- month follow up if webspace reconstruction after
SCC excision with reverse DMCA ap
Pitfalls
• Take care when dissecting around the pedicle just
proximal to the MCPJ; taking a cuff of surrounding
tissue and a cutaneous tail can help to avoid injury
at this zone.
• The Foucher ap is not ideal for volar thumb resurfacing as it does not provide glabrous tissue (free
pulp transfer is the gold standard).
• The Foucher ap may struggle to reach the very tip
of the thumb and may require IPJ exion to achieve
closure.
• Donor sites can be stiff or require skin grafts; utilize
hand therapy services to minimize stiffness.
• Care must be taken to use bipolar cautery on a low
setting; making use of micro ligaclips for any small
branches may help avoid thermal injury.
26.10 Selected Readings
• Maruyama Y.The reverse dorsal metacarpal ap. British
journal of plastic surgery, 1990; 43:24–27.
• Maruyama described the reverse dorsal metacarpal
ap, reporting a consistent vascular basis and a role in
P. Singh et al.
covering small soft tissue defects of the hand. Eight
cases were included in the study, and the reverse dorsal
metacarpal ap was utilized to reconstruct wide range
of defects, a result of acute trauma, burn ulcerations,
tumors, syndactyly, and contractures. The aps were
raised to include the fascia over the dorsal interosseous
muscles, the proximal DMA was divided, and the arch
of rotation was the distal metacarpal, at connections
between the terminal branches and the palmar metacarpal and digital arteries. The constancy of second
dorsal metacarpal artery was demonstrated as the
artery most frequently used. The author reports good
outcomes in seven of the eight cases, reporting distal
partial necrosis of one case based on the fth dorsal
metacarpal artery [3].
• Foucher G, Braun J.A New Island Flap Transfer from the
Dorsum of the Index to the Thumb. Plast Reconstruct
Surg J. 1979: 63;344–349.
• Foucher et al. describe an island “Kite” ap from the
dorsum of the index nger, raised on the rst dorsal metacarpal artery with one or two veins and innervated by
terminal branches of the radial nerve. From 30 cadaveric
specimens, the anatomy of the FDMA was delineated and
the operative technique described. The vascular bundle is
reported to be reliable; in 12 cases the authors report no
ap necrosis. This ap can be used for reconstruction of
thumb defects [1].
• Quaba A, Davison PM. The distally based dorsal hand
ap. Br J Plast Surg. 1990: 43;28–39.
• The authors describe a distally based dorsal hand ap
raised on a direct cutaneous branch of the second, third,
and fourth dorsal metacarpal artery. Anatomical studies
are supplemented with a clinical series of 21 patients. This
ap was used to reconstruct defects (post-excisional for
skin lesions, burns, and contractures) on the dorsum of the
metacarpals, phalanges, distal palm, and web spaces. In
21 cases, they report one ap failure and one partial ap
loss, both intended to reconstruct distal palmar defects.
Most donor sites were amendable to direct closure; others
required split- thickness or full- thickness skin grafts [4].
• Omokawa S, Tanaka Y, Ryu J, Kish V. The anatomical
basis for reverse rst to fth dorsal metacarpal arterial
aps. J Hand Surg(British and European Volume). 2004:
30B;40–44.
• Omokawa etal. studied the cutaneous vascularity aris-
ing from the rst to the fth dorsal metacarpal arteries
in order to understand the anatomical basis of reverse
dorsal metacarpal arterial aps. This cadaveric specimen study demonstrated that the rst to the third metacarpal arteries consistently anastomose with the
palmar arterial system. Each artery gave off four to
eight skin perforators along the length of the metacarpal. The diameter of the perforators was larger at the
distal third of the metacarpal; therefore it may contrib-
26 Dorsal Metacarpal Artery Flaps
257
ute most of the dorsal cutaneous vascularity of the
hand. Fourth and fth dorsal metacarpal arteries
passed palmary into the interosseous muscles at the
mid-level of the metacarpal. Anatomy of the fth metacarpal was found to be more variable and seldom
reached the metacarpophalangeal joint (MCPJ); thus
it can only be used in cases where it does extend to the
MCPJ [7].
• Yoon T, Carrera A, Benito-Ruiz J, Ferreres A, SerraRenom J.The anatomical basis of the fourth dorsal metacarpal ap: a cadaveric dissection. J Hand surg. 2006:
31A;711–716.
• Yoon etal. studied the vascularization of the fourth dorsal
intercarpal space demonstrating consistency of the distal
recurrent branch of the dorsal metacarpal artery. These
ndings suggest that aps may be reliably raised based
solely on the distal recurrent branch. Excluding the fourth
dorsal metacarpal artery increases efciency of dissection
with a proposed reduction in donor site morbidity [8].
References
1. Foucher G, Braun JB.A new island ap transfer from the dorsum
of the index to the thumb. Plast Reconstr Surg. 1979;63(3):344–9.
2. Holevich J.A new method of restoring sensibility to the thumb. J
Bone Joint Surg Br. 1963;45:496–502.
3. Maruyama Y.The reverse dorsal metacarpal ap. Br J Plast Surg.
1990;43(1):24–7.
4. Quaba AA, Davison PM.The distally-based dorsal hand ap. Br J
Plast Surg. 1990;43(1):28–39.
5. Sherif MM.First dorsal metacarpal artery ap in hand reconstruction. I.Anatomical study. J Hand Surg Am. 1994;19(1):26–31.
6. Unluer Z, Ruston J, Nikkhah D. The retrograde approach to the
reverse dorsal metacarpal artery ap. J Plast Reconstr Aesthet Surg.
2020;
7. Omokawa S, Tanaka Y, Ryu J, Kish VL.The anatomical basis for
reverse rst to fth dorsal metacarpal arterial aps. J Hand Surg Br.
2005;30(1):40–4.
8. Yoon TS, Carrera A, Benito-Ruiz J, Ferreres A, Serra-Renom
JM. The anatomic basis of the fourth dorsal metacarpal ap: a
cadaveric dissection. J Hand Surg Am. 2006;31(5):711–6.
Digital Artery Flaps: Homodigital and
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Heterodigital Island Flaps
SirkeRinko, JuliaRuston, andDariushNikkhah
27
27.1 Introduction
Homodigital island aps relocate tissue from a nonessential
area of the digit to an area needing robust coverage or a nongraftable wound bed [1]. They are based on one of the two
digital arteries to each nger and rely on the knowledge that
sacrice of one artery does not (usually) compromise perfusion to the digit. Weeks and Wray rst described the
homodigital island ap based on the digital artery in 1973 to
cover soft tissue defects on the proximal digit. Homodigital
island aps can be anterograde and advanced distally for
pulp defects (such as the oblique triangular neurovascular
ap of Venkataswami and Subramanian [2]). This is commonly indicated for volar oblique amputations of the digit.
Reverse-ow aps have facilitated pulp reconstruction
further, based on retrograde ow through the digital artery,
via anastomosis from the contralateral side (Lai etal. [3] and
Kojima et al. [4]). These are indicated for ngertip and
nailbed reconstruction, but can also be used to cover defects
on the dorsum over the distal interphalangeal joint. Lai
describes how the ap is outlined over the lateral donor proximal phalanx according to the site and shape of the defect; this
is then raised with the distal digital artery acting as a pedicle.
An extended ap incorporating dorsal skin over the metacarpophalangeal joint is also described for major nger defects
in which the standard ap does not provide sufcient cover.
Koshima etal. [5] described the digital artery perforator
(DAP) ap, and there are numerous subsequent “freestyle”
perforator ap variations. The digital artery perforator ap is
used for resurfacing the ngertip; the ap is based on the
medial or lateral aspect of the nger proximal to the defect.
S. Rinkoff · J. Ruston · D. Nikkhah (*)
Royal Free Hospital, London, UK
e-mail: s.rinkoff@nhs.net; julia.ruston@nhs.net; d.nikkhah@nhs.net
During ap elevation the digital artery perforator and the
subcutaneous venular system near the defect are preserved,
and the ap is then rotated 180° into the defect.
The concept of elevating an islanded ap based on antegrade digital artery ow is credited to Moberg and Littler,
although Esser may have been the rst person to describe an
“island ap” in 1917. In 1961, Tubiana and Duparc described
further principles of a neurovascular heterodigital skin island
ap, such as selecting donor site and how to elevate the ap.
The heterodigital island ap has the advantage of importing (potentially neurotized) glabrous skin into another digit
which may be too extensively injured for a homodigital ap
or where the defect is too proximal for a reverse ap (e.g.,
over the middle phalanx). It can be useful for large volar
defects where return of sensation is critical, e.g., thumb pulp.
The donor site is usually the ulnar side of the middle or radial
side of the ring nger. The disadvantage of the heterodigital
ap is that it requires morbidity to another digit, and there
have been problems with cross-localization of sensation to
the donor digit, cold intolerance, and hyperesthesia or paresthesia of the donor digit.
27.2 Anatomy ofHomo- andHeterodigital
Island Flaps
The digital artery runs along the ulnar and radial aspects of
the nger, dorsal to the digital nerve, within a fatty-areolar
channel between Cleland’s and Grayson’s ligaments. Each
nger has two palmar digital arteries, the larger and most
dominant of which is usually the closest toward the midline
(e.g., ulnar digital artery of the index and radial digital artery
of the little nger) (as described by Haerle etal. [6]). The
middle and ring ngers often demonstrate codominant digital vessels, and therefore homodigital aps are especially
suited to these ngers, with least risk of inadequate perfusion
or cold intolerance, after dividing one artery for the ap.
Digital artery diameter varies in size from approximately
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