Atlas Phẫu Thuật Vi Phẫu Mạch Máu (Atlas of Microvascular Surgery)

originates from the distal part of the artery, running
horizontally.
The tendinous insertion of the pectoralis m inor
(5) can be divided to get a fuller exposure of the second
or even the rst part of the artery, if necessary.
The lateral thoracic artery is 1.5 mm in diameter;
the subscapular artery is 3 to 4 mm.
Brachial Artery
The artery begins at the level of the lower border of the
teres major and ends in the cubital fossa at the level of
the neck of the radius by dividing into the radial and
ulnar arteries.
DISSECTION AND IDENTIFICATION OF
ANATOMIC STRUCTURES (FIG. 1 – 2 8 )
Dissection proceeds to identify and protect the brachial
plexus (9). The axillary artery (7) is isolated by incising
the vascular sheath along its line of pulsation. The
axillary vein (8) is below the artery.
There are several branches arising from this
part of the artery. The lateral thoracic artery (11)
follows the lateral border of the pectoralis m inor; the
subscapular artery (10) arises at the lower border of
the scapularis (17), running dow nward; the posterior
hum eral circum ex artery (13) arises near the take-
off of the subscapular artery, running backward;
and the anterior hum eral circum flex artery (13)
RECIPIENT SITE EXPOSURES
29
Figure 1–28
Dissection and identi cation of anatomic structures.
1. Deltoid m.
7. Axillary a.
13. Anterior and posterior
2. Short head of biceps m.
8. Axillary v.
humeral circum ex a.
3. Coracobrachialis m.
9. Brachial plexus
14. Median n.
4. Pectoralis major m.
10. Subscapular a.
15. Musculocutaneous n.
5. Pectoralis minor m.
11. Lateral thoracic a.
16. Latissimus dorsi m.
6. Cephalic v.
12. Thoracoacromial a.
17. Subscapularis m.

Medial Approach to the Proximal
Part of the Brachial Artery and
Deep Brachial Artery
INCISION (FIG. 1 – 2 9 )
The arm is abducted at a right angle in maximal supina-
tion. The skin incision begins in the axillary fossa and
runs along the lower border of the pectoralis m ajor
and the groove between the coracobrachialis and the
long head of the triceps.
30
I.1 UPPER EXTREMITY: SHOULDER, ARM, AND AXILLA
Figure 1–29
Incision.
1. Coracobrachialis m.
8. Brachial a.
2. Short head of biceps
9. Brachial v.
3. Pectoralis major m.
10. Deep brachial a.
4. Triceps m.
11. Median n.
5. Teres major m.
12. Ulnar n.
6. Latissimus dorsi m.
13. Radial n.
7. Sheath of brachial a.
14. Musculocutaneous n.

RECIPIENT SITE EXPOSURES
31
EXPOSURE OF NEUROVASCULAR
BUNDLE (FIG. 1 – 3 0 )
Deepening the incision through the subcutaneous and
fascial layers, the coracobrachialis m uscle (1) is ex-
posed between the biceps (2) and triceps (4), and the
neurovascular bundle can be identi ed by its pulsation
at the lower border of the coracobrachialis.
Figure 1–30
Exposure of neurovascular bundle.
1. Coracobrachialis m.
2. Short head of biceps
3. Pectoralis major m.
4. Triceps m.
5. Teres major m.
6. Latissimus dorsi m.
7. Sheath of brachial a.

DISSECTION AND IDENTIFICATION OF
ANATOMIC STRUCTURES (FIG. 1 – 31 )
Retracting the coracobrachialis (1), the m usculocuta-
neous nerve (14), the median nerve (11), and the ulnar
nerve (12) are carefully dissected out in a direction an-
terior, medial, and posterior to the artery, respectively.
The brachial vein (9) courses more super cially in the
lower portion of the wound.
Retracting the median nerve anteriorly, the proxi-
mal part of the brachial artery (8) is isolated. Just below
the lower border of the teres major (5), the deep brachial
artery (10) arises from the posterior aspect of the
brachial artery, accompanies the radial nerve (13), and
runs backward. The deep brachial artery, with a
diameter
of 2.5 mm, is available for end-to-end
anastomosis.
32
I.1 UPPER EXTREMITY: SHOULDER, ARM, AND AXILLA
Figure 1–31
Dissection and identi cation of anatomic structures.
1. Coracobrachialis m.
9. Brachial v.
2. Short head of biceps m.
10. Deep brachial a.
3. Pectoralis major m.
11. Median n.
4. Triceps m.
12. Ulnar n.
5. Teres major m.
13. Radial n.
6. Latissimus dorsi m.
14. Musculocutaneous n.
8. Brachial a.

Exposure of the Middle Part of the Brachial
Artery
INCISION (FIG. 1 – 3 2 )
An incision is made over the groove between the biceps
and the long head of the triceps in the midportion of
the arm.
RECIPIENT SITE EXPOSURES
33
Figure 1–32
Incision.
1. Biceps m.
5. Medial cutaneous n. of forearm
2. Coracobrachialis m.
6. Sheath of brachial a.
3. Triceps m.
7. Brachial a. and v.
4. Basilic v.
8. Median n.

EXPOSURE OF SUPERFICIAL STRUCTURES
(FIG. 1 – 3 3 )
The deep fascia is carefully incised over the groove. The
basilic vein (4) usually perforates the deep fascia and
joins the brachial vein in this region. The m edial
cutaneous nerve of the forearm (5) accompanies the
basilic vein (4) and lies m edial to the brachial artery in
the upper half of the arm.
34
I.1 UPPER EXTREMITY: SHOULDER, ARM, AND AXILLA
Figure 1–33
Exposure of super cial structures.
1. Biceps m.
4. Basilic v.
2. Coracobrachialis m.
5. Medial cutaneous n. of forearm
3. Triceps m.
6. Sheath of brachial a.

DISSECTION AND IDENTIFICATION OF
ANATOMIC STRUCTURES (FIG. 1 – 3 4 )
The neurovascular sheath is divided. The median nerve
(8) crosses the artery from anterior to posterior, and it is
retracted anteriorly. Dissection proceeds to isolate the
brachial artery (7).
RECIPIENT SITE EXPOSURES
35
Figure 1–34
Dissection and identi cation of anatomic structures.
1. Biceps m.
5. Medial cutaneous n. of forearm
2. Coracobrachialis m.
7. Brachial a. and v.
3. Triceps m.
8. Median n.
4. Basilic v.

Posterior Approach to the Deep
Brachial Artery and the Proximal
Portion of the Brachial Artery
INCISION (FIG. 1 – 3 5 )
An incision is m ade on the lateral edge of the long
head of the triceps, beginning 5 cm below the
acrom ial angle and running distally to the olecranon
for 8 to 10 cm .
36
I.1 UPPER EXTREMITY: SHOULDER, ARM, AND AXILLA
Figure 1–35
Incision.
1. Deep brachial a.
6. Long head of triceps m.
2. Radial n.
7. Medial head of triceps m.
3. Deltoid m.
8. Brachial a.
4. Teres major m.
9. Median n.
5. Lateral head of triceps m.
10. Ulnar n.

w ith sharp dissection. At this stage, the deep brachial
artery (1) and the radial nerve (2) appear below
the teres m ajor (4), running obliquely on the m edial
head of the triceps (7) from m edial to lateral and
disappearing between the lateral and m edial heads of
the triceps (5,7).
EXPOSURE OF DEEP BRACHIAL ARTERY AND
RADIAL NERVE (FIG. 1 – 3 6 )
Dividing the deep fascia below the posterior edge of
the deltoid (3), the septum between the long and lat-
eral heads of the triceps (5,6) is identi ed and entered
w ith blunt dissection and then developed distally
RECIPIENT SITE EXPOSURES
37
Figure 1–36
Exposure of deep brachial artery and radial nerve.
1. Deep brachial a.
5. Lateral head of triceps m.
2. Radial n.
6. Long head of triceps m.
3. Deltoid m.
7. Medial head of triceps m.
4. Teres major m.

separated from the long head of the triceps (6). The
brachial artery (8) can be found behind the ulnar nerve
(10). During the procedure, attention should be paid to
protect the branch of the radial nerve to the long head,
which runs more transversely than its parent trunk.
38
I.1 UPPER EXTREMITY: SHOULDER, ARM, AND AXILLA
EXPOSURE OF BRACHIAL ARTERY (FIG. 1 – 37 )
The deep brachial artery (1) and radial nerve (2) are
displaced laterally and protected. Retracting the long
head of the triceps (6) medially, the medial edge of the
medial head of the triceps (7) is identi ed, and then
Figure 1–37
Exposure of brachial artery.
1. Deep brachial a.
6. Long head of triceps m.
2. Radial n.
7. Medial head of triceps m.
3. Deltoid m.
8. Brachial a.
4. Teres major m.
9. Median n.
5. Lateral head of triceps m.
10. Ulnar n.

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Corm ack GC, Lam berty BGH. Fasciocutaneous vessels
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39

elbow, where the cephalic vein gives off the m edian
cubital vein and the deep communicating branch with
the venae comitantes of the radial artery. It then runs
distally and laterally along the radial side of the forearm
in the subcutaneous layer. A constant branch arises
from the artery 7 cm above the wrist joint.
Generally, all the forearm skin can be adequately
supplied by the fasciocutaneous branches of the distal
part of the radial artery.
Anatomy of the Ulnar Artery (2)
Beginning at the same point as the radial artery (1), the
ulnar artery (2) passes distally and medially across and
under the pronator teres (7), the m edian nerve, the
exor carpi radialis (8), and the exor digitorum super-
cialis (10). It reaches the medial side of the forearm at
about midway between the elbow and the wrist. It then
runs between the exor carpi ulnaris (12) and the exor
digitorum super cialis (10) m uscles or tendons. The
ulnar nerve is adjacent and m edial to the lower two
thirds of the artery.
At the w rist, the ulnar artery crosses the exor
retinaculum lateral to the pisiform bone, and ends by
dividing into the deep palmar branch and the super cial
palmar branch.
Shortly after its origin, the artery im m ediately
gives off the anterior and posterior ulnar recurrent
arteries and the common interosseous artery (5). Distal
to the com m on interosseous artery, the ulnar artery
gives off three to ve fasciocutaneous branches between
the exor carpi ulnaris (12) and the exor digitorum
super cialis (10) that join the rich subcutaneous vascu-
lar network already described. The largest and m ost
constant among these branches is that situated 4 cm
distal to the common interosseous artery (5).
FOREARM FLAPS
Anatomy of the Radial Artery (1)
(Fig. 2–1)
After passing under the bicipital aponeurosis (11), the
brachial artery divides into radial and ulnar arteries
(1,2) 1 cm below the bend of the elbow. The radial
artery (1) passes deeply between the brachioradialis
(6) and pronator teres (7) m uscles in the upper third of
its course, and between the tendons of the brachioradi-
alis and exor carpi radialis (8) in the lower two thirds
of its course. Growing gradually super cial, it is covered
only by skin and fascia at the wrist. It then winds back-
ward, around the lateral side of the carpus, beneath the
tendons of the abductor pollicis longus and extensor
pollicis brevis. Passing through the “snuff box” and the
interspace between the rst and second m etacarpal
bones, it form s the deep palmar arch by uniting with
the deep branch of the ulnar artery.
Beside the radial recurrent artery (4) branching
near its origin and the superficial palm ar branch
arising just above the w rist, the radial artery gives off
9 to 17 fasciocutaneous branches. In the proxim al half
of its course that is covered by the brachioradialis
m uscle, there are 4.2 branches on average (range: 0 to
10), and in the distal half that is directly under the
skin and fascia, there are 9.6 branches on average
(range: 4 to 14). All these branches, w ith an average
diam eter of 0.5 m m (range: 0.1 to 1.1 m m ), form a rich
vascular network in the subcutaneous layer, w ith fas-
ciocutaneous branches from the ulnar, interosseous,
and brachial arteries.
The most proximal branch sometimes arises from
the recurrent radial artery. It has a diameter of 0.5 to
1.0 m m and is nam ed the inferior cubital artery. It
em erges from the septum between the brachioradialis
and pronator teres, and 4 cm below the bend of the
2
Forearm Region
N

FOREARM FLAPS
41
Figure 2–1
Anatomy of the radial and ulnar arteries.
1. Radial a.
2. Ulnar a.
3. Super cial palmar arch
4. Radial recurrent a.
5. Common interosseous a.
6. Brachioradialis m.
7. Pronator teres m.
8. Flexor carpi radialis m.
9. Palmaris longus m.
10. Flexor digitorum super cialis m.
11. Bicipital aponeurosis
12. Flexor carpi ulnaris

42
I.2 UPPER EXTREMITY: FOREARM REGION
Variations of the Radial Artery in the
Forearm and Wrist (Fig. 2–2)
A. The radial artery may arise higher in the axilla or the
upper arm in 12% of individuals.
B. It may lie super cially on the brachioradialis or even
over the deep fascia of the forearm.
C. At the wrist, the radial artery may wind around su-
per cial to the tendons of the abductor pollicis
longus and extensor pollicis brevis.
D. The radial artery m ay be slender or even absent,
whereas the median artery becomes larger and con-
tributes to the formation of the deep and super cial
palmar arches.
Figure 2–2
Variations of the radial artery in the forearm and wrist (see text for details).

FOREARM FLAPS
43
Variations of the Ulnar Artery in the
Forearm (Fig. 2–3)
A. The ulnar artery may arise relatively high from the
brachial artery and, rarely, from the axillary artery.
In cases of high origin, the artery alm ost always
courses super cial to the exor muscles in the fore-
arm, situated beneath the deep fascia—rarely, in the
subcutaneous layer. The com m on interosseous
artery m ay originate from the radial or brachial
artery.
B. The ulnar artery m ay occasionally arise relatively
lower. At a level 5 to 7 cm distal to the elbow, it
diverges from the radial artery. The com m on in-
terosseous artery m ay arise directly from the
brachial artery.
Figure 2–3
Variations of the ulnar artery in
the forearm (see text for details).

Figure 2–5
The profundus cubitalis vein, communicating
between the deep and super cial venous system in the cubital
fossa.
1. Cephalic v.
9. Venae comitantes and radial a.
3. Median cubital v.
10. Brachial a. and v.
7. Profundus cubitalis v.
11. Brachioradialis m.
8. Coalesced v.
Venous Drainage (Figs. 2–4, 2–5, 2–6, 2–7)
Both the super cial and deep systems are equally capable
of draining the forearm ap. In the super cial system, the
cephalic vein (1) from the dorsal venous network ascends
around the radial border of the forearm to its anterior
surface, receiving tributaries from both surfaces. Below
the front of the elbow, it gives off the median cubital vein
(3), which receives a communicating branch (7) from the
deep vein (9), and passes medially to join the basilic vein
(2). Then, the cephalic vein ascends to the anterolateral
aspect of the arm, super cial to the groove between the
brachioradialis and the biceps at the elbow.
The basilic vein (2), receiving the dorsal venous
network of the hand, ascends for about two thirds of its
extent along the posterior ulnar border of the forearm.
It then inclines forward to the medial bicipital groove.
The median vein of the forearm (4), draining the
palmar venous plexus, ascends on the front of the fore-
arm and ends in the basilic or median cubital vein.
Paired venae com itantes of the radial artery (9)
coalesce into a single vein (8) before the level of the
bifurcation of the brachial artery. The profundus
cubitalis vein (7), as a communicating venous perfora-
tor, connects this coalesced deep vein (9) to the cephalic
(1) or median (3) cubital vein in the cubital fossa. It may
be bene cial for the venous drainage of the forearm ap
if the profundus cubitalis vein (7) is included in the
pedicle, and the anastomosis for veins is made proximal
to it during ap transfer.
Figure 2–4
Anatomy of venous drainage and cutaneous
innervation.
1. Cephalic v.
2. Basilic v.
3. Median cubital v.
4. Median v. of forearm
5. Lateral cutaneous n. of forearm
6. Medial cutaneous n. of forearm

FOREARM FLAPS
45
Variations of the Super cial Veins
(Fig. 2–6)
A. Cephalic predominance: The mainstream of the
basilic vein may go to the cephalic vein via the median
cubital vein. The basilic vein may become smaller or
may be absent above the elbow.
B. Basilic predom inance: The m ainstream of
the
cephalic vein m ay go to the basilic vein via the
Figure 2–6
Variations of the super cial veins of the forearm and elbow (see text for details).
median cubital vein. The cephalic vein may become
smaller or may be absent above the elbow.
C. Absence of
the m edian antecubital vein: The
tributaries of the palm ar venous network m ay
directly join the cephalic and basilic veins, and
the m edian cubital vein may rem ain for communica-
tion between these two veins.

46
I.2 UPPER EXTREMITY: FOREARM REGION
Retrograde Deep Venous System
(Fig. 2–7)
The radial or ulnar artery is accompanied by a pair of
venae comitantes. Even though some valves do exist in
these deep veins (average: 3.6 valves for each), reverse
forearm aps are widely and successfully reported
for reconstructions of the hand. In this type of ap, a
retrograde venous drainage is accom plished by a
“crossover” pattern through several com m unicating
branches (2) between the two venae com itantes (1),
and by a “bypass” pattern through the collateral
branches.
A. Antegrade venous ow
B. Retrograde venous ow
Figure 2–7
Mechanism of the venous drainage
in the retrograde deep venous system.
1. Venae comitantes
2. Communicating branch
3. Collateral branch

FOREARM FLAPS
47
Innervation (Fig. 2–4)
The lateral cutaneous nerve of the forearm (5) is a con-
tinuation of the m usculocutaneous nerve. It passes
deep to the cephalic vein (1) at the elbow and then de-
scends along the radial border of the forearm to the
wrist. It supplies the skin over the lateral half of the an-
terior surface of the forearm . The m edial cutaneous
nerve of the forearm (6) pierces the deep fascia with the
basilic vein at about the middle of the arm and divides
into anterior and posterior branches. The anterior
branch descends anterior to the basilic vein at the el-
bow and supplies the skin over the medial half of the
anterior surface of the forearm . The posterior branch
lies anterior to the medial epicondyle of the hum erus
and supplies the skin over the medial third of the pos-
terior surface of the forearm.
Measurements
Diameter (mm)
Radial
Artery
2.5
Vein
1.3
Ulnar
Artery
2.5
Vein
2.3
Cephalic
Vein
2.8
Basilic
Vein
2.6
Several fasciocutaneous branches constantly arise from
the radial and ulnar arteries through the intermuscular
septa to form a very rich vascular network in the subcu-
taneous and deep fascial layers of the forearm. There-
fore, the forearm ap based on the radial vessels is
remarkably hardy and robust. Also, it is able to provide a
large territory, including almost all the forearm skin and
the lower third of the arm, on which the shape, size, and
location of the ap can be designed very freely.
The quite super cial and constant anatomy of the
radial artery and its large caliber and long vascular pedi-
cle facilitate easy harvesting, dissection, and microsurgi-
cal transfer of the ap. This donor site provides thin and
pliable skin, with ne texture and scanty subcutaneous
tissue. However, the lateral forearm skin is relatively
hairy, especially in Caucasian males.
This ap can be combined with a segment of the
radius bone, the brachioradialis, exor carpi radialis, and
palmaris longus muscles or tendons, and the super cial
branch of the radial nerve. Medial and lateral cutaneous
nerves of the forearm provide sensibility for the skin ap.
Because it has the excellent properties described
herein, the radial forearm ap is very versatile and
widely applied in reconstructive microsurgery: (1) for fa-
cial reconstruction involving soft-tissue defects, with or
without mandibular bone loss; (2) in intraoral recon-
struction for oral lining in mucosal defects, with or with-
out mandibular bone loss; (3) for repair of defects in the
lower limb, especially because the sensory forearm ap
may be suitable for resurfacing weight-bearing areas; (4)
for penile reconstruction with an innervated sensory
forearm ap; (5) for reconstructing pharyngoesophageal
defects or even reconstruction of the cervical trachea,
using a tubed forearm ap; and (6) for reconstruction of
the tongue with an innervated sensory ap.
The radial artery of the ap can be anastom osed at
both ends as a ow-through graft to save an acutely
ischem ic extrem ity that has resulted from a segm ental
defect of its m ain artery, with wide loss of soft tissue.
The osteocutaneous ap provides a lim ited seg-
m ent of cortex bone of radius, useful in reconstruction
of non–weight-bearing areas, such as in m andibular
defects. The ap can also be a tendinocutaneous one.
The reversed island ap is very useful in hand surgery
to reconstruct soft tissue, tendon, or bone defects; also,
a thum b can be reconstructed with a fabricated re-
versed osteocutaneous ap. If cosmesis of the forearm
is very important, a purely fascial ap can be used to
cover a wound; this requires the use of a split-thickness
skin graft to cover the fascial ap.
The donor defect is usually covered with a split-thick-
ness skin graft, except in cases of narrow aps or purely
fascial aps. Results may include some cosmetic prob-
lems, especially if the defect is on the lateral aspect of the
forearm. Medial deviations in ap design may obviate this
problem to some extent and provide a less hairy ap.
It is not mandatory to repair the radial artery when
the hand has good circulation after ap harvesting.
However, to prevent postoperative fracture of the
radius when creating an osteocutaneous ap, taking the
bone with the ap should not include more than 40% of
the cross section, and the arm should be imm obilized in
an above-elbow plaster cast for at least 3 weeks.
Compared with the radial forearm ap, the ulnar
forearm ap possesses similar properties. However, the
ulnar forearm ap and its axis are located on the medial
aspect of the forearm; therefore, it may produce better
cosmetic results and avoid a hairy ap. The proximal
arterial pedicle is lim ited distal to the takeoff of the
com m on interosseous artery, and fewer case reports
would seem to require further clinical experience
before freely recom m ending this ap. Nevertheless,
the ulnar forearm ap might be a real alternative to the
radial forearm ap.
COMMENT AND INSIGHTS

RADIAL FOREARM FLAP
Possible Skin Territory Supplied by
the Radial Artery (Fig. 2–8)
The territory of this ap m ay be extended from the
lower third of the anterior aspect of the arm proximally
to the wrist exion crease distally. Distal width is from
Figure 2–8
Possible skin territory supplied by the radial artery.
1. Radial a. and its venae comitantes
7. Flexor carpi ulnaris m.
13. Pronator quadratus m.
2. Brachioradialis m.
8. Basilic v.
14. Lateral cutaneous n. of forearm
3. Cephalic v.
9. Medial cutaneous n. of forearm
15. Supinator m.
4. Flexor carpi radialis m.
10. Median v. of forearm
16. Pronator teres m.
5. Flexor digitorum super cialis m.
11. Median cubital v.
17. Median n.
6. Palmaris longus m.
12. Super cial branch of radial n.
18. Flexor pollicis longus m.
N
the extensor hallucis longus tendon radially to the ex-
tensor carpi ulnaris tendon ulnarly. Proximal width is
from the lateral to medial humeral epicondyles.

RADIAL FOREARM FLAP
49
Distal Dissection (Fig. 2–10)
A pneumatic tourniquet is applied only with elevation
exsanguination.
At the distal border of the ap, the radial vascular
bundle (1) is identi ed at the lateral edge of the exor
carpi radialis tendon (4) and dissected out. The cephalic
vein (3) is isolated on the distal lateral edge of the ap
and ligated.
Figure 2–10
Distal dissection.
1. Radial a. and its venae comitantes
2. Brachioradialis m.
3. Cephalic v.
4. Flexor carpi radialis m.
5. Flexor digitorum super cialis m.
6. Palmaris longus m.
7. Flexor carpi ulnaris m.
17. Median n.
Flap Design (Fig. 2–9)
A line is draw n from a point 1 cm below the center of
the antecubital fossa to the tubercle of the scaphoid,
corresponding to the surface anatomy of the radial
artery and the anterolateral interm uscular septum .
The radial forearm ap is usually designed along this
line as an axis, although the ap can be som ewhat de-
viated m edially for hairless skin. Along the axis, any
part—distal, m iddle, or proxim al—can be used for the
ap, depending on requirem ents at the recipient site.
Preoperatively, it is imperative that the patency of
the ulnar artery be con rmed with an Allen’s test, by ul-
trasonic Doppler owmeter testing, or by arteriography.
Figure 2–9
Flap design.

50
I.2 UPPER EXTREMITY: FOREARM REGION
Dissection on the Ulnar Distal Side
(Fig. 2–11)
The distal ulnar portion of the ap, including the deep
fascia, is elevated from the exor muscles and tendons,
toward the lateral edge of the exor carpi radialis (4). This
procedure is usually performed gradually from distal to
proximal, tracing the exposed radial vascular bundle. Al-
though the palmaris longus (6) is not required in the ap,
the deep fascia that encircles it should be divided,
preserving the palmaris longus on the forearm. Special
attention should be paid to preserve paratenons on all
the tendons, and not to damage the fasciocutaneous
branches emerging from the intermuscular septum.
Figure 2–11
Dissection on the ulnar distal side.
4. Flexor carpi radialis m.
5. Flexor digitorum super cialis m.
6. Palmaris longus m.
7. Flexor carpi ulnaris m.

RADIAL FOREARM FLAP
51
Dissection on the Ulnar Proximal Side
(Fig. 2–12)
At the proximal medial border of the ap, the basilic
vein (8) is dissected out, and the m edial cutaneous
nerve of the forearm (9) can be identi ed near the vein;
it m ay be included with the ap if a sensory ap is
required.
Figure 2–12
Dissection on the ulnar proximal side.
8. Basilic v.
9. Medial cutaneous n. of forearm
10. Median v. of forearm
11. Median cubital v.
16. Pronator teres m.

52
I.2 UPPER EXTREMITY: FOREARM REGION
Dissection on the Radial Side
(Fig. 2–13)
The radial portion of the ap is raised from the brachio-
radialis (2) toward its medial edge. Retracting the mus-
cle laterally, the radial vascular bundle (1) connecting
with the ap is dissected from its base up to its takeoff
from the brachial artery. The fasciocutaneous perfora-
tors arising from the radial artery are visualized. During
the dissection, the super cial branch of the radial nerve
(12) should be identi ed and preserved.
Figure 2–13
Dissection on the radial side.
1. Radial a. and its venae comitantes
2. Brachioradialis m.
3. Cephalic v.
12. Super cial branch of radial n.
13. Pronator quadratus m.
18. Flexor pollicis longus m.

RADIAL FOREARM FLAP
53
Dissection on the Radial Proximal
Side (Fig. 2–14)
At the proxim al lateral edge of the ap, the cephalic
vein (3) is isolated, and the lateral cutaneous nerve of
the forearm (14) is identi ed near the vein over the
groove between the brachioradialis (2) and the biceps
muscles. Generally, the cephalic vein (3) is selected for
venous drainage of the ap. The proximal length of the
cephalic vein (3) can be dissected to be as long as
required. The basilic vein is preserved for the donor site,
if possible.
Both ends of the radial artery can be selected as a
pedicle for microvascular anastomosis. Before cutting
the radial artery at either end, the circulation of the
hand should be carefully assessed after releasing the
tourniquet and clamping the artery at its distal end.
Figure 2–14
Dissection on the radial proximal side.
2. Brachioradialis m.
3. Cephalic v.
14. Lateral cutaneous n. of forearm
15. Supinator m.

54
I.2 UPPER EXTREMITY: FOREARM REGION
Completion of Flap Harvesting
(Fig. 2–15)
The radial forearm ap with an antegrade blood ow is
ready for transfer after the distal end of the radial vas-
cular bundle (1) is divided and ligated.
Figure 2–15
Completion of ap harvesting.
1. Radial a. and its venae comitantes
3. Cephalic v.
9. Medial cutaneous n. of forearm
11. Median cubital v.
14. Lateral cutaneous n. of forearm

RADIAL FOREARM FLAP FOR PENILE RECONSTRUCTION
55
RADIAL FOREARM FLAP FOR PENILE
RECONSTRUCTION
Preparation of the Harvested Flap
(Fig. 2–16)
A radial forearm ap with a width of 13 cm and a
length of 12 cm is raised with its sensory nerves. The
outer surface of the ap is divided into areas A (1), B (2),
and C (3). Area A (1) is to be the inner surface of the ure-
thra, 2.0 to 3.0 cm in width. Area B (2) is 0.5 to 1.0 cm in
width and is deepithelialized. Area C (3) is to be the
outer surface of the penis and is 8 to 10 cm in width. A
small skin tongue ap is designed on the middle of its
distal edge to form the ori ce of the urethra.
Figure 2–16
Preparation of the harvested ap.
1. Area A
2. Area B
3. Area C
4. Radial a. and v.
5. Cephalic v. and lateral cutaneous n. of
forearm
6. Basilic v. and medial cutaneous n. of
forearm.
N

56
I.2 UPPER EXTREMITY: FOREARM REGION
Urethral Creation (Fig. 2–17)
Area A (1) is sutured to roll around a catheter with its
skin surface inside.
Figure 2–17
Urethral creation.
1. Area A
2. Area B
3. Area C
4. Radial a. and v.
5. Cephalic v. and lateral cutaneous n. of forearm
6. Basilic v. and medial cutaneous n. of forearm

RADIAL FOREARM FLAP FOR PENILE RECONSTRUCTION
57
Figure 2–18
Completion of penile fabrication.
1. Area A
3. Area C
4. Radial a. and v.
5. Cephalic v. and lateral cutaneous n. of forearm
6. Basilic v. and medial cutaneous n. of forearm
Completion of Penile Fabrication
(Fig. 2–18)
Area C (3) is overwrapped around with its skin surface
outside. The distal edges of areas A and C are sutured to
each other to create the ori ce of the urethra.
Cross-Sectional Diagram of Penile
Fabrication (Fig. 2–19)
A constructed penis is illustrated in cross section.
Figure 2–19
Cross-sectional diagram of penile fabrication.
1. Area A
2. Area B
3. Area C
4. Radial a. and v.
5. Cephalic v. and lateral cutaneous n. of forearm
6. Basilic v. and medial cutaneous n. of forearm

58
I.2 UPPER EXTREMITY: FOREARM REGION
REVERSED RADIAL FOREARM
ISLAND FLAP
Flap Design (Fig. 2–20)
A point of pulsation of the radial artery (2) at the wrist
is chosen as a rotation axis. The pedicle length of the
reversed ap (3) should be equal to or 1 cm more than
the distance between the defect (1) on the hand and
this axial point. Flap elevation is similar to the proce-
dure described previously.
Figure 2–20
Flap design.
1. Wound defect debrided
2. Rotation axis
3. Skin ap
Note: This type of ap is widely applied in hand reconstructions. The
retrograde arterial blood ow comes from the ulnar artery through
the deep palmar arch, whereas the venae comitantes are responsible
for venous drainage in a retrograde direction. At the outset,
engorgement of the veins with progressive swelling of the ap
occurs after ligating the proximal vascular pedicle; however, venous
drainage will improve in a few days through the communicating and
collateral branches described previously.
N
Flap Elevation and Reversed Island
Transfer (Fig. 2–21)
The proximal radial vascular bundle is divided and lig-
ated distal to the bifurcation of the brachial artery. Its
distal pedicle (4) can be further dissected to the wrist,
sometimes even to the snuff box, passing the ap with
its pedicle underneath the abductor pollicis long and
extensor pollicis brevis, to obtain a longer pedicle
length for transfer to the hand.
Figure 2–21
Flap elevation and reversed island transfer.
1. Wound defect debrided
4. Radial a. and v.

RADIAL FOREARM OSTEOCUTANEOUS FLAP
59
RADIAL FOREARM
OSTEOCUTANEOUS FLAP
Bony Segment Proposed (Fig. 2–22)
An anterolateral segm ent of the radial bone that lies
between the insertions of the pronator teres (1) and the
brachioradialis (2) can be included in a radial forearm
ap. A length of up to 10 cm and 40% of the cross
section of the radius may be safely removed. The radius
m ust be splinted with an above-elbow cast for 3 to
4 weeks because fractures have been reported.
The segm ent of the radius is nourished by two
fascioperiosteal branches through the interm uscular
septum, and m usculoperiosteal branches through the
exor pollicis longus and pronator quadratus from the
radial artery.
Figure 2–22
Bony segment proposed.
1. Pronator teres m. or its insertion
2. Brachioradialis m. or its insertion
3. Super cial branch of radial n.
4. Periosteum and intermuscular septum
5. Radius bone
6. Radial a. and v.
7. Flexor pollicis longus m.
8. Pronator quadratus m.
9. Cephalic v. and lateral cutaneous n. of forearm
N

60
I.2 UPPER EXTREMITY: FOREARM REGION
Flap Elevation toward the Vascular
Bundle and Bony Segment (Fig. 2–23)
The ap is raised from both the radial and ulnar sides,
as already described, until the anterolateral intermus-
cular septum (4) containing the radial vessels is
reached. Laterally retracting the brachioradialis (2), the
super cial branch of the radial nerve (3) is protected,
and the periosteum (4) is incised longitudinally beyond
the attachment of the septum to the radius bone (5).
Figure 2–23
Flap elevation toward the vascular bundle and
bony segment.
2. Brachioradialis m. or its insertion
3. Super cial branch of radial n.
4. Periosteum and intermuscular septum
5. Radius bone
6. Radial a. and v.
9. Cephalic v. and lateral cutaneous n. of forearm

RADIAL FOREARM OSTEOCUTANEOUS FLAP
61
Medial Exposure of the Bony Segment
(Fig. 2–24)
Medially retracting the exor carpi radialis, the m uscle
bellies of the exor pollicis longus (7) and pronator
quadratus (8) are divided and elevated, to reach the
periosteum of the radius (5) and to incise it.
Figure 2–24
Medial exposure of the bony segment.
1. Pronator teres m. or its insertion
5. Radius bone
7. Flexor pollicis longus m.
8. Pronator quadratus m.

62
I.2 UPPER EXTREMITY: FOREARM REGION
Osteotomy and Accomplishment of
the Flap (Fig. 2–25)
The radius bone segment (5) is divided with a Gigli’s
saw, and the osteocutaneous ap is elevated, with
attention paid to preserve the interm uscular septum
with the ap and an intact segm ent of the radius.
Figure 2–25
Osteotomy and
accomplishment of the ap.
5. Radius bone
6. Radial a. and v.
9. Cephalic v. and lateral cutaneous n. of
forearm

RADIAL FOREARM TENDINOCUTANEOUS FLAP
63
RADIAL FOREARM
TENDINOCUTANEOUS FLAP
Tendons Proposed (Fig. 2–26)
The brachioradialis (1), exor carpi radialis (3), and pal-
maris longus (2) tendons are available, single or in com-
bination, for a vascularized transfer with the forearm
ap. These tendons are nourished by a series of small
transverse branches from the radial artery communi-
cating with the subfascial plexus.
Figure 2–26
Tendons proposed.
1. Brachioradialis m.
2. Palmaris longus m.
3. Flexor carpi radialis m.
4. Radial a. and v.
5. Median n.
6. Pronator teres m.
7. Cephalic v.
8. Flexor pollicis longus m.
9. Pronator quadratus m.
N

64
I.2 UPPER EXTREMITY: FOREARM REGION
Completion of the Tendinocutaneous
Flap (Fig. 2–27)
The radial forearm ap, with the brachioradialis (1),
exor carpi radialis (3), and palm aris longus (2) ten-
dons, is shown elevated, with the dissection under-
neath these tendons keeping them intact with the ap.
Figure 2–27
Completion of the
tendinocutaneous ap dissection.
1. Brachioradialis m.
2. Palmaris longus m.
3. Flexor carpi radialis m.
4. Radial a. and v.
5. Median n.
6. Pronator teres m.
7. Cephalic v.
8. Flexor pollicis longus m.
9. Pronator quadratus m.

HYBRID RADIAL FOREARM FLAP
65
HYBRID RADIAL FOREARM FLAP
This ap maintains continuity of the cephalic vein
while the radial artery is anastomosed in the neck
or head to a recipient vessel for a distant transfer.
Flap Harvesting and Venous
Dissection (Fig. 2–28)
The radial forearm ap is elevated, as previously
described. An incision is proxim ally extended
along the lateral border of the biceps (3) in the
arm, and along the groove between the deltoid (4)
and the pectoralis major. The cephalic vein (2) is
dissected up to near the clavicle.
Figure 2–28
Flap harvesting and venous dissection.
1. Radial a.
2. Cephalic v.
3. Biceps brachii m.
4. Deltoid m.
N

66
I.2 UPPER EXTREMITY: FOREARM REGION
Flap Transfer (Fig. 2–29)
The radial artery (1) is ligated near its proxim al end,
and the ap is passed through a subcutaneous tunnel to
reach the recipient area in the head and neck (e.g., for a
defect on the face), while the cephalic vein (2) is still
kept in continuity in the tunnel as an island transfer.
After the ap has settled down into the defect, the
radial artery (1) is anastomosed to the facial artery (5).
Figure 2–29
Flap transfer.
1. Radial a.
2. Cephalic v.
5. Facial a.

ULNAR FOREARM FLAP
67
ULNAR FOREARM FLAP
Flap Design (Fig. 2–30)
A line is drawn from the m edial epicondyle of the
humerus to the lateral edge of the pisiform bone. The
surface anatomy of the ulnar artery (2) commences at a
point 1 cm below the center of the antecubital fossa via
the junction of the upper and middle thirds of the line,
running distally along the line. The upper third of the
artery runs deep to the pronator teres, the exor carpi
radialis, the palmaris longus, and the exor digitorum
super cialis (4). The ap is therefore outlined on the
m edial aspect of the forearm along the m iddle and
lower thirds of the surface line of the ulnar artery, used
as an axis for the ap.
Figure 2–30
Flap design.
1. Basilic v. and medial cutaneous n. of forearm
2. Ulnar a., v., and n.
3. Flexor carpi ulnaris m.
4. Flexor digitorum super cialis m.
5. Common interosseous a.
6. Flexor digitorum profundus m.
7. Median n.
N

68
I.2 UPPER EXTREMITY: FOREARM REGION
Neurovascular Dissection on the
Distal and Proximal Aspects
(Fig. 2–31)
Distally, the ulnar vascular bundle (2) is dissected out
and separated from the ulnar nerve in the anterior
medial intermuscular septum between the exor carpi
ulnaris and exor digitorum super cialis tendons.
Proxim ally, the basilic vein and the medial cutaneous
nerve of the forearm (1) are isolated.
Figure 2–31
Neurovascular dissection on the distal
and proximal aspects.
1. Basilic v. and medial cutaneous n. of forearm
2. Ulnar a., v., and n.

ULNAR FOREARM FLAP
69
Dissection from the Ulnar Aspect
(Fig. 2–32)
The medial portion of the ap, with the deep fascia, is
raised from the exor carpi ulnaris (3) toward the inter-
muscular septum at the lateral edge of this muscle. Pre-
serving the fascia and branches in the septum , the
exor carpi ulnaris is retracted medially to expose the
ulnar vessels (2).
Figure 2–32
Dissection from the ulnar aspect.
1. Basilic v. and medial cutaneous n. of forearm
2. Ulnar a., v., and n.
3. Flexor carpi ulnaris m.

70
I.2 UPPER EXTREMITY: FOREARM REGION
70
I.2 UPPER EXTREMITY: FOREARM REGION
70
I.2 UPPER EXTREMITY: FOREARM REGION
Dissection from the Radial Aspect
(Fig. 2–33)
The lateral portion of the ap with the deep fascia is
elevated from the exor m uscles toward the septum.
The ulnar vascular bundle is separated from its base
and the ulnar nerve. Retracting the exor digitorum
super cialis (4) laterally, the ulnar vessels (2) are
dissected proximally up to the takeoff of the common
interosseous artery (5).
70
I.2 UPPER EXTREMITY: FOREARM REGION
Figure 2–33
Dissection from the radial aspect.
2. Ulnar a., v., and n.
4. Flexor digitorum super cialis m.
5. Common interosseous a.
6. Flexor digitorum profundus m.
7. Median n.

ULNAR FOREARM FLAP
71
Accomplishment of Flap Elevation
(Fig. 2–34)
At this point, the circulation of the hand should be
assessed by clamping the ulnar artery. Then, the ulnar
vessels (2) are divided proxim ally, just distal to the
common interosseous artery. The basilic vein (1) can be
dissected proxim ally for a suf cient length. If it is
required, a longer length for the arterial pedicle can be
obtained with the distal dissection of the ulnar vascular
bundle.
Figure 2–34
Accomplishment of ap elevation.
1. Basilic v. and medial cutaneous n. of forearm
2. Ulnar a., v., and n.
3. Flexor carpi ulnaris m.
6. Flexor digitorum profundus m.
Note:The ulnar forearm ap can include the exor carpi ulnaris and palmaris longus muscles as a myocutaneous ap and
a segment of the ulnar bone as an osteocutaneous ap. It can also be used as a reversed island ap similar to the radial
forearm ap.

72
I.2 UPPER EXTREMITY: FOREARM REGION
INTEROSSEOUS FOREARM FLAP
Arterial Anatomy (Figs. 2–35, 2–36)
About 1 cm after its origin from the ulnar artery (1), the
comm on interosseous artery divides into the anterior
and posterior interosseous arteries (AIA and PIA).
The AIA runs downward between the exor digito-
rum profundus (4) and exor pollicis longus (5) with
the anterior interosseous nerve (10), along the anterior
surface of the interosseous mem brane. At the proximal
border of the pronator quadratus (8), the artery divides
into two terminal branches. The anterior branch contin-
uously runs distally between the pronator quadratus
muscle and interosseous membrane to join the palmar
carpal network; the posterior branch penetrates the
interosseous m em brane to anastom ose with the PIA
and then descends to join the dorsal carpal network.
After its penetration, it also gives off a dorsal cutaneous
branch, w hich runs between the extensor digitorum
tendons and the extensor pollicis longus tendon onto
the extensor retinaculum near Lister’s tubercle to
supply the dorsal skin of the wrist.
The PIA, with a diameter of 1.2 to 1.5 mm, smaller
than the AIA, passes between the oblique cord and the
upper border of the interosseous m em brane and
em erges at the lower border of the supinator at about
the level between the upper and m iddle thirds of the
forearm. It then descends in the intermuscular septum
between the extensor carpi ulnaris and extensor digito-
rum m inimi. In its proximal third, the PIA lies deep in
the septum on the abductor pollicis longus m uscle,
accompanied by the posterior interosseous nerve. After
that, it becom es m ore super cial on the extensor
pollicis longus and extensor indicis m uscles, alm ost
im mediately beneath the deep fascia in its middle and
distal thirds.
Figure 2–35
Anatomy of the common interosseous and anterior interosseous
arteries. (Adapted with permission from Yu HL, Chase R, Strauch B. Atlas of Hand
Anatomy and Clinical Implications. St. Louis: Mosby;2004:409.)
1. Ulnar a.
2. Common interosseous a.
3. Anterior interosseous a.
4. Flexor digitorum profundus m.
5. Flexor pollicis longus m.
6. Median a.
7. Posterior interosseous a.
8. Pronator quadratus m.
9. Median n.
10. Anterior interosseous n.
N

INTEROSSEOUS FOREARM FLAP
73
Figure 2–36
Anatomy of the posterior interosseous artery. (Adapted with
permission from Yu HL, Chase R, Strauch B. Atlas of Hand Anatomy and Clinical
Implications. St. Louis: Mosby;2004:410.)
1. Posterior interosseous a.
2. Interosseous recurrent a.
3. Supinator m.
4. Posterior interosseous n.
5. Abductor pollicis longus m.
6. Extensor pollicis longus m.
7. Extensor indicis m.
8. Posterior terminal branch of the anterior interosseous a.
The PIA receives an anastomotic branch from the
AIA 3 cm proximal to the distal radioulnar joint and
then extends to join the dorsal carpal arch. Usually, the
anastomotic branch between the AIA and PIA, with an
average diameter of 0.7 mm (range: 0.2 to 1.2 mm), is
located underneath the tendon of the extensor indicis.
Im mediately after emerging in the posterior aspect
of the forearm , the PIA gives off the interosseous recur-
rent artery, running proxim ally in the m uscle bers
of the supinator (3) to the interval between the lateral
epicondyle and olecranon.
In the intermuscular septum between the extensor
carpi ulnaris and extensor digitorum minimi, the PIA
gives off 4 to 7 septocutaneous perforators and multiple
m uscular branches. Among the septocutaneous perfo-
rators, the m ost proxim al one is usually larger and
arises from the PIA within 2 to 3 cm after its emergence.
Som etim es it m ay be given off from the recurrent
interosseous artery.
After it gives off a large m uscular branch to the
extensor digitorum in its proxim al third, the posterior
interosseous artery becomes narrow, with a diameter
of 0.3 to 0.6 mm in its middle third in 90% of cases.
Occasionally, it m ay be absent there. Som e authors
consider it to be the “choke anastomosis” between the
PIA and AIA, and the distal part of the PIA could be the
recurrent dorsal branch of the AIA.
In its middle third, it consistently gives off the mid-
dle cutaneous perforator, the vena comitans of which is
one of the communicating veins between the super -
cial and deep venous systems. This perforator should
always be included in the ap when harvesting; it may
improve the venous drainage for the ap.
In its distal third, the PIA gives off 6 to 8 cutaneous
perforators with variable diameters.
There are one or two venae comitantes accompa-
nying the PIA, with diameters of 2 to 3 mm.

74
I.2 UPPER EXTREMITY: FOREARM REGION
Possible Variations of the Arterial
Anatomy (Fig. 2–37)
A. A typical pattern of the PIA.
B. The anastom otic branch between the AIA and PIA at
the distal forearm is absent in 2 to 3% of cases.
C. The PIA runs out after its em ergence and gives off
some branches to the muscles and skin in the upper
posterior compartment of the forearm, instead of a
large recurrent branch from the AIA, after its pene-
tration through the interosseous membrane, form-
ing the distal half of the PIA. This occurs in 5.7% of
cases.
D. The m ost proxim al septocutaneous perforator
(arrow) may arise from the interosseous recurrent
artery in 23% of cases. Occasionally, it may arise from
the common interosseous artery.
Figure 2–37
Variations of the arterial anatomy (see text for details).

INTEROSSEOUS FOREARM FLAP
75
Relationship with the Posterior
Interosseous Nerve (Fig. 2–38)
After its emergence from the supinator in the posterior
com partm ent of
the forearm , the posterior in-
terosseous nerve, as a termination of the deep branch of
the radial nerve, descends together with the PIA on its
radial side, dividing into multiple m uscular branches to
supply the muscles in the posterior compartment of the
forearm. Among these branches, the one to the exten-
sor carpi ulnaris m ay cross over the PIA after its most
proximal septocutaneous perforator takes off.
A. The motor branch to the extensor carpi ulnaris is un-
derneath the PIA in 80% of cases.
B. The motor branch to the extensor carpi ulnaris is su-
per cial to the PIA, and an adequately sized septocu-
taneous perforator exists distal to it in 14% of cases.
C. The motor branch to the extensor carpi ulnaris is su-
per cial to the PIA, but there is no adequately sized
septocutaneous perforator a short distance distal to
it in 6% of cases.
Sensibility in the posterior skin area of the forearm
is provided by the posterior cutaneous nerve, w hich
arises from the radial nerve in the upper arm . After
penetrating the deep fascia and dividing into anterior
and posterior branches, it runs at the front and back of
the lateral epicondyle of the humerus at the elbow.
Figure 2–38
Relationship of PIA and its branches with the posterior interosseous nerve (see text for details).

76
I.2 UPPER EXTREMITY: FOREARM REGION
The posterior interosseous flap involves a newly
developed donor site. Its m ost usual application is as a
reversed ap to cover defects on the hand or w rist,
such as those resulting from correction of adduction
contracture of the rst web space. The ap can also be
used as a direct pedicle flap for coverage of defects
near the elbow joint. The rst case of a free ap was
reported in 1989, in which a planned reversed pedicle
ap was abandoned during surgery, because of an in-
sufficient anastom otic branch from the AIA. Subse-
quently, other free posterior interosseous aps have
been reported for use in reconstruction of skin defects
on the ngers and for salvage of a degloved nger, or
on the dorsum of the hand and in the rst web, when
the reversed posterior interosseous flap is not indi-
cated because of old traum a, such as previous fracture
at the wrist.
Based on the posterior interosseous vessels, the
ap, whether reversed or free, does not require sacri ce
of any main artery, and it can easily reach the hand,
wrist, and elbow as a local transfer. It can also be used
in distant transfer as a free ap.
Generally, the anatomy of the PIA and its comm u-
nication with the AIA are relatively constant and, with
their adequate vessel diam eters, a direct pedicle ap
would be quite reliable. Although the reversed ap is
more widely applied clinically, the anastomotic branch
from the AIA should be carefully evaluated during
surgery. Among 79 cases of reversed aps reported in
the literature, three aps were abandoned and partial
necrosis occurred in seven cases, most probably result-
ing from variation or insuf cient diameter of the anas-
tomotic branch from the AIA.
Venous drainage in the reversed ap can be effec-
tive through the venae com itantes.
The donor site provides a skin ap of sm all to
m edium size. The skin texture on the posterior aspect
of the forearm is ne, thin, and a little hairy.
A donor-site defect with a width of less than 4 cm
after ap harvesting on the forearm could be closed di-
rectly. Donor morbidity is minimal, even if the motor
nerve branch to the extensor carpi ulnaris has to be di-
vided and repaired.
The reversed posterior interosseous osteocuta-
neous ap is especially convenient for reconstruction of
skin defects with metacarpal bone loss on the dorsum
of the hand. The ulna is broad and triangular at the level
at which the ap is taken, so that a postoperative frac-
ture is unlikely.
The anterior interosseous ap (or dorsal wrist ap)
is based on the dorsal cutaneous branch/anterior in-
terosseous artery system. It is a small-sized skin ap and
is applied mostly for skin defects of the thumb or n-
gers. Its convenience depends on its availability in the
same region. The donor defect can be closed directly, if
its width is less than 2.5 cm, and it does not require sac-
ri ce of a main blood supply for the hand. There is no
postoperative donor morbidity. However, this ap still
needs m ore clinical trials and anatom ic investigation
because reports of its use are currently limited.
COMMENT AND INSIGHTS

POSTERIOR INTEROSSEOUS FLAP (POSTERIOR FOREARM FLAP)
77
POSTERIOR INTEROSSEOUS FLAP
(POSTERIOR FOREARM FLAP)
Flap Design (Fig. 2–39)
The patient is positioned supine, with the forearm lying
over the abdomen and the elbow exed 90 degrees. A
line drawn from the lateral epicondyle of the humerus
to the distal radioulnar joint is divided into three equal
parts. The junction of the upper and m iddle linear
thirds is around the location of the emergence of the PIA.
The ap is designed in the territory centering at the
middle and distal thirds of the line, usually with a width
of 5 to 7 cm. The distal limit is placed 3 to 4 cm above the
wrist joint to avoid damage to the dorsal branch of the
ulnar nerve (5); the proximal limit can exceed 2 to 3 cm
over the level of the emergence of the PIA.
Generally, the ap, transferred with a direct pedicle
(antegrade ow), is designed on the middle and distal
thirds of the forearm, whereas a ap with a reversed
pedicle (retrograde ow) is designed m ainly on the
middle third of the forearm. For a revascularized free
ap, the whole territory described above could be ap-
plicable.
Figure 2–39
Flap design.
1. PIA and its perforators
6. Posterior interosseous n.
2. Extensor digiti minimi m.
7. Tendon of extensor indicis
3. Extensor carpi ulnaris m.
8. Extensor digitorum m.
4. Anastomis branch of AIA
9. Supinator m. (see the text details).
5. Dorsal branch of ulnar n.
N