(Trang không có chữ)
GLUTEUS MAXIMUS FLAP
Anatomy (Figs. 4–1, 4–2)
Description of the Gluteus
Maximus Muscle (1)
This is one of the largest m uscles in the hum an
body. In shape, it is broad, flat, thick, and
quadrilateral. The m uscle dim ensions are
150 m m in length, 147 m m in w idth, and
22 m m in thickness at the m idpoint. The ori-
gins of the m uscle involve the posterior
gluteal line of the ilium , the aponeurosis of
the erector spinae, the dorsal surface of the
lower part of the sacrum, the side of the coccyx,
and the sacrotuberous ligam ent (3). The upper
part and the superficial fibers of the lower
part are attached to the iliotibial tract of the
fascia lata and the deep ber of the lower part
to the gluteal tuberosity of the fem ur. The
m uscle functions to extend the hip and to
rotate the thigh laterally.
4
Gluteal Region
Figure 4–1
Anatomy of blood supply and innervation
in the gluteal region.
1. Gluteus maximus m.
2. Piriformis m.
3. Sacrotuberous
ligament
4. Superior gluteal a.
5. Inferior gluteal a.
6. Super cial branch of
superior gluteal a.
7. Deep branch of
superior gluteal a.
8. Sciatic n.
9. Superior gluteal n.
10. Inferior gluteal n.
11. Upper branch of
superior gluteal a.
12. Lower branch of
superior gluteal a.
13. Superior cluneal n.
14. Gluteus medius m.
15. Gluteus minimus m.
16. Posterior femoral
cutaneous n.
Blood Supply
The gluteus m axim us is supplied m ainly by both the
superior and inferior gluteal arteries (4,5). The superior
gluteal artery (4) is the terminal branch of the posterior
trunk of the internal iliac artery. It passes out of the
pelvis above the piriform is m uscle (2), through the
greater sciatic foramen, and shortly thereafter, divides
into super cial and deep branches (6,7).
The superficial branch (6) runs underneath the
upper part of the gluteus m axim us (1) for a short
distance, and enters the m uscle to supply it. In the
m uscle, it divides into m ultiple branches. Som e of
them anastom ose w ith the inferior gluteal artery, and
Measurements
Vessels
Diameter (mm)
Length of Pedicle (cm)
Superior gluteal
Artery
2.0–3.0
2–3
Vein
2.0–4.0
Inferior gluteal
Artery
2.5–3.5
2–3
Vein
2.5–4.0
others becom e myocutaneous perforators to supply
the overlying skin.
The deep branch (7) lies between the gluteus
medius (14) and iliac bone and runs superoanteriorly
for 1 cm , then quickly divides into upper and lower
branches (11,12). The upper branch (11) goes superoan-
teriorly along the anterior gluteal line; that is, the origin
of the gluteus minimus (15), toward the anterior supe-
rior iliac spine, to anastomose with the deep circum ex
iliac artery, giving off nutrient branches to the iliac
crest.
The lower branch passes obliquely between the
gluteus medius and minimus (14,15) toward the poste-
rior aspect of the hip joint, and gives off branches to
supply these muscles and the joint.
The gluteus maximus ap or superior gluteal artery
perforator (S-GAP) ap is based on the arterial system
of the superior gluteal artery—superficial branch—
myocutaneous perforators.
Vascularized iliac bone grafts also can be based on
the arterial system of the superior gluteal artery—deep
branch—upper branch—nutrient branches—iliac bone.
The surface anatomy of the emergence of the supe-
rior gluteal artery (4) from the pelvis can be repre-
sented by a junction at the upper and middle thirds of a
line from the posterior superior iliac spine to the apex
of the greater trochanter of the femur.
The inferior gluteal artery (5) is the term inal
branch of the anterior trunk of the internal iliac artery.
It passes out of the pelvis below the piriformis m uscle
(2), through the greater sciatic foramen. Before it de-
scends between the tuberosity of the ischium and the
greater trochanter of the femur, the inferior gluteal ar-
tery (5) gives off branches to the undersurface of the
lower portion of the gluteus m axim us (1). Som e of
these branches penetrate the m uscle to supply the
overlying skin as myocutaneous perforators.
As it passes over the lower border of the gluteus
m axim us, the inferior gluteal artery continues as a
direct cutaneous branch, accompanying the posterior
cutaneous nerve of the thigh to the popliteal fossa.
The surface anatomy of the em ergence of the
inferior gluteal artery (5) from the pelvis can be rep-
resented by the m idpoint of a line connecting the
posterior superior iliac spine and the tuberosity of the
ischium .
130
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–2
Diagram of the gluteus maximus muscle
and its blood supply.
1. Gluteus maximus m.
4. Superior gluteal a.
5. Inferior gluteal a.
Innervation (Figs. 4–1, 4–3)
The gluteus maximus m uscle (1) is supplied by the in-
ferior gluteal nerve (10), which leaves the pelvis below
the piriform is (2) and divides into branches entering
the deep surface of the gluteus maximus (1), along with
the inferior gluteal artery (5).
The posterior femoral cutaneous nerve (16) issues
from the pelvis through the greater sciatic foramen below
the piriformis, with the inferior gluteal vascular bundle
(5). It descends deep to the fascia lata with the direct cuta-
neous branch of the inferior gluteal artery (5). Its branches
are distributed to the lower portion of the gluteal region,
the perineum, and the exor aspect of the thigh and leg.
The skin sensation of the m ost gluteal region is
supplied by the superior cluneal nerves (13), which
originate from the dorsal rami of the rst, second, and
third lumbar nerves and penetrate the deep fascia just
above the iliac crest. There may be two or three such
small nerves, accompanied by tiny vessels, lateral to the
posterior superior iliac spine along the iliac crest.
Figure 4–3
Sensory distribution of the
cutaneous nerve in the gluteal region.
13. Superior cluneal n.
16. Posterior femoral cutaneous n.
17. Iliohypogastric n.
18. Dorsal rami of L 1,2,3
GLUTEUS MAXIMUS FLAP
131
132
II.4 LOWER EXTREMITY: GLUTEAL REGION
In the gluteal region, there is an abundance of material
with the adipose tissue and the gluteus maximus m us-
cle, which can be harvested on a vascular pedicle of
either the superior or inferior gluteal vessels as free
vascularized tissue transfers. Because of its special loca-
tion, this donor site is often used to provide an island
ap for local transfer, to treat decubitus ulcers in the
ischial or sacral area, or for perineal defects.
The gluteus m axim us is one of the im portant
m uscles in hum ans for standing erect, walking, run-
ning, and clim bing. Use of a m uscle ap based on the
inferior gluteal neurovascular pedicle m ay cause a
total functional loss of the m uscle because the inferior
gluteal nerve supplies the w hole m uscle. This ap has
been reported m ainly in the treatm ent of paraplegic
patients. However, a m uscle ap based on the supe-
rior gluteal vessels causes only partial loss of function
and strength, so that it is m ore acceptable than a ap
based on the inferior gluteal vessels. The superior
gluteal myocutaneous flap can be used for breast
reconstruction, and it provides a large am ount of fat
and m uscle tissue from the buttock. In such recon-
structions, due to the short length of the vascular
pedicle, the internal m am m ary vessels under the fth
costal cartilage are com m only used as recipient vessels
for direct anastom oses; otherw ise, vein grafts would
be advisable.
The gluteal thigh ap, which is based on the infe-
rior gluteal vessels with the lower part of the muscle,
provides the possibility for a sensate ap from the but-
tock and back of the thigh.
The donor defect can be closed directly, and donor
scar and contour are inconspicuous and acceptable.
Postoperative morbidity after muscle loss and shortness
of the vascular pedicle in both gluteal aps limit the ex-
tent of application in microvascular reconstruction.
The S-GAP ap has been developed to avoid the
disadvantages described above. By dissection of a my-
ocutaneous perforator away from the muscle, the m us-
cle is preserved and its pedicle length can reach to 8 cm.
In addition, the ap can be sensate if the superior
cluneal nerves are dissected with the ap. The defect
after ap harvest can be directly closed if its width is
less than 13 cm. With proper ap design, the resultant
scar can be easily hidden by a bathing suit.
The only disadvantage, as with other perforator
aps, is that more time is necessary during surgery to
dissect the multiple branches out from the perforator in
the muscle.
The S-GAP ap is used for breast reconstruction. It
provides projection with its abundant adipose tissue
even better than do other perforator aps.
There have been only a few cases reported of the
vascularized iliac bone graft based on the superior
gluteal vessels, and its reliability might be clari ed by
further anatom ic investigations and clinical applica-
tions. The pedicle length is so short that anastomosis
m ust be performed under dif cult conditions. Usually,
an additional vein graft is necessary. For these reasons,
if a vascularized iliac bone graft is needed, one based on
the deep circum ex iliac artery should be recom -
m ended as the rst choice.
COMMENTS AND INSIGHTS
SUPERIOR GLUTEUS
MYOCUTANEOUS FLAP
Flap Design (Fig. 4–4)
The axis of the ap is a line from the posterior superior
iliac spine to the apex of the greater trochanter of the
femur. The emergence of the superior gluteal artery is
at the junction of the upper and middle thirds of the
line. The width of the ap can approach 13 cm and still
allow for the direct closure of the donor defect. The
usual shape of the ap is elliptical, and the size generally
10 cm in width and 30 cm in length.
SUPERIOR GLUTEUS MYOCUTANEOUS FLAP
133
Figure 4–4
Flap design.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Gluteus minimus m.
4. Piriformis m.
5. Superior gluteal a. and v.
6. Super cial branch of the
superior gluteal artery
7. Deep branch of the
superior gluteal artery
Exposure of the Upper Lateral Edge of
the Muscle (Fig. 4–5)
The rst incision is begun along the superior and lateral
borders, exposing the lateral edge of the gluteus max-
im us (1). Then, blunt dissection proceeds between the
muscle and the gluteus medius (2).
134
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–5
Exposure of the upper lateral
edge of the muscle.
1. Gluteus maximus m.
2. Gluteus medius m.
Figure 4–6
Approach to the vascular pedicle.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Gluteus minimus m.
4. Piriformis m.
5. Superior gluteal a. and v.
6. Super cial branch of the superior gluteal
artery
7. Deep branch of the superior gluteal artery
Approach to the Vascular
Pedicle (Fig. 4–6)
After the exposed portions of the m uscle origin and
insertion are divided, the superior gluteal vessels can be
exposed between the gluteus medius (2) and piriformis
(4) muscles, 5 cm lateral to the sacral edge. The deep
branch of the superior gluteal artery (7) is divided. The
gluteus minimus (3) is seen at the depth of the wound.
Completion of Flap
Elevation (Fig. 4–7)
The rest of the elliptical skin incision is com pleted;
then, the upper third of the gluteus maximus (1) is used
in the ap and the muscle is separated at a line beyond
the entrance of the superior gluteal vessels (5). The
myocutaneous ap is isolated on its vascular pedicle,
which can be dissected proxim ally up to 2 or 3 cm ,
separating the superior gluteal nerve from it.
SUPERIOR GLUTEUS MYOCUTANEOUS FLAP
135
Figure 4–7
Completion of ap elevation.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Gluteus minimus m.
4. Piriformis m.
5. Superior gluteal a. and v.
6. Super cial branch of the superior
gluteal artery
GLUTEAL THIGH FLAP (BASED ON THE
INFERIOR GLUTEAL VESSELS)
Flap Design (Fig. 4–8)
The central axis of this ap is m idway between the
greater trochanter and the ischial tuberosity and perpen-
dicular to the gluteal crease, whereas the inferior gluteal
artery leaves the pelvis at about the midpoint of a line
joining the posterior superior iliac spine and the ischial
tuberosity. To permit direct closure, ap width should be
less than 12 cm; ap length can range from 12 to 34 cm.
136
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–8
Flap design.
1. Gluteus maximus m.
2. Direct cutaneous branch of
inferior gluteal a. and v.
3. Hamstring m.
4. Sciatic n.
5. Piriformis m.
6. Inferior gluteal a., v., and n.
7. Ischial tuberosity
8. Superior gemellus m., internal
obturator m., and inferior
gemellus m.
9. Quadratus femori
10. Adductor brevis and magnus m.
11. Posterior femoral cutaneous n.
Distal Elevation of the Flap (Fig. 4–9)
The distal part of the ap, including the fascia lata of the
thigh, is raised over the hamstring muscles (3) and the
caudal edge of the m uscle (1) is exposed.
GLUTEAL THIGH FLAP (BASED ON THE INFERIOR GLUTEAL VESSELS)
137
Figure 4–9
Distal elevation of the ap.
1. Gluteus maximus m.
2. Direct cutaneous branch of inferior
gluteal a. and v.
3. Hamstring m.
Detaching the Muscle (Fig. 4–10)
The insertions of the gluteus maximus are incised to the
degree necessary for ap m obility, but no higher than
the greater trochanter. The sciatic nerve (4), the poste-
rior fem oral cutaneous nerve (11), and the inferior
gluteal neurovascular bundle (6) are identi ed below
the piriform is (5).
138
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–10
Detaching the muscle.
1. Gluteus maximus m.
4. Sciatic n.
5. Piriformis m.
6. Inferior gluteal a., v., and n.
7. Ischial tuberosity
8. Superior gemellus m.,
internal obturator m.,
and inferior gemellus m.
9. Quadratus femoris
10. Adductor brevis and magnus m.
11. Posterior femoral cutaneous n.
Completion of Flap Elevation
(Fig. 4–11)
The upper portion of the incision is completed, and the
gluteus maximus muscle (1) is divided, keeping a dis-
tance from the entrance of the neurovascular pedicle.
The gluteal thigh ap is isolated on the inferior gluteal
and neurovascular bundle (6) and posterior fem oral
cutaneous nerve (11). While harvesting the ap, the
perineal branch of the posterior femoral cutaneous nerve
and superior muscular branches of the inferior gluteal
nerve should be left intact, if possible.
GLUTEAL THIGH FLAP (BASED ON THE INFERIOR GLUTEAL VESSELS)
139
Figure 4–11
Completion of ap elevation.
1. Gluteus maximus m.
5. Piriformis m.
6. Inferior gluteal a., v., and n.
8. Superior gemellus m., internal
obturator m., and inferior gemellus m.
11. Posterior femoral cutaneous n.
VASCULARIZED ILIAC BONE GRAFT
(BASED ON THE SUPERIOR
GLUTEALVESSELS)
Incision (Fig. 4–12)
The incision is m ade from the point between the poste-
rior and middle thirds of the iliac crest, running along
the crest anteriorly. At a point 4 cm posterior to the
anterior superior iliac spine, it turns inferiorly to the
greater trochanter of the fem ur.
140
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–12
Incision.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Tensor fasciae latae m.
4. Iliac crest
5. Deep superior branches of superior
gluteal a., v., and n.
6. Gluteus minimus m.
7. Iliacus m.
8. Three layers of muscles of abdominal wall
9. Inner table of iliac bone
Approach to the Gluteus
Medius (Fig. 4–13)
The skin ap is elevated to expose the gluteus medius (2).
The interspaces between the gluteus m axim us (1),
medius (2), and tensor fasciae latae (3) are identi ed.
VASCULARIZED ILIAC BONE GRAFT (BASED ON THE SUPERIOR GLUTEAL VESSELS)
141
Figure 4–13
Approach to the gluteus medius.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Tensor fasciae latae m.
Exposure of the Neurovascular
Bundle (Fig. 4–14)
The gluteus medius muscle (2) is divided, leaving 1 to
2 cm on the iliac bone. Then, the deep superior branches
of the superior gluteal vessels (5) and the superior
gluteal nerve (5) are identi ed, just above the attach-
ment of the gluteus minim us (6). The vascular bundle is
carefully dissected to separate the nerve from it, and
the origins of the gluteus m axim us (1) and tensor
fasciae latae can be partially detached to expose the
gluteus m edius widely.
142
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–14
Exposure of the neurovascular bundle.
1. Gluteus maximus m.
2. Gluteus medius m.
4. Iliac crest
5. Deep superior branches of superior gluteal a., v., and n.
6. Gluteus minimus m.
Inner Ilium Approach (Fig. 4–15)
The origins of the three layers of the abdominal muscle
(8) are sharply divided from the iliac crest, and the ilia-
cus m uscle (7) is detached subperiosteally to expose
the inner surface of the ilium (9).
VASCULARIZED ILIAC BONE GRAFT (BASED ON THE SUPERIOR GLUTEAL VESSELS)
143
Figure 4–15
Inner ilium approach.
4. Iliac crest
7. Iliacus m.
8. Three layers of muscles of abdominal wall
9. Inner table of iliac bone
Osteotomy (Fig. 4–16)
The required segment of ilium is divided, with care not
to damage the vascular pedicle. Then, the vascularized
iliac bone, based on the deep superior branch of the
superior gluteal vessels (5), is raised. Alternatively, only
the outer table may be harvested for non–weight-bearing
indications.
144
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–16
Osteotomy.
1. Gluteus maximus m.
2. Gluteus medius m.
5. Deep superior branches of
superior gluteal a., v., and n.
6. Gluteus minimus m.
SUPERIOR GLUTEAL ARTERY
PERFORATOR FLAP (S-GAP FLAP)
Newly modi ed from the superior gluteal myocutaneous
flap, the S-GAP ap takes a large amount of skin and
subcutaneous tissue in the gluteal region by its perfora-
tors. It leaves the muscle intact, greatly eliminates post-
operative m orbidity, and m akes the vascular pedicle
longer. In the applications for breast reconstruction
using this region, the S-GAP ap has almost completely
substituted for the superior gluteal myocutaneous ap.
Flap Design and Doppler
Detection (Fig. 4–17)
Detection of the perforator and ap design. Before
Doppler detection of the perforator, two lines should be
marked in the gluteal region. A line is made from the
posterior superior iliac spine to the apex of the greater
trochanter of the femur. The emergence of the superior
gluteal artery is located at the point between the proxi-
mal and middle thirds of the line. A second line is made
from the midpoint between the posterior superior iliac
spine and the coccyx to the apex of the greater trochanter
of the femur. It represents the axis of the piriformis.
Usually, the main perforator of the superior gluteal
artery can be detected by Doppler owmeter in the area
above the second line, laterodistal to the em ergence
point of the superior gluteal artery and parallel to the
rst line.
Generally, the ap axis can be varied; it can be
horizontal or vertical. However, most patients request
that the postoperative scar be hidden under a bathing
suit, and a fusiform ap is usually designed over the
detected perforator as the center. Its axis is parallel to
the bikini oblique line. Usually, the size of the ap can
be 10
25 cm, and up to 12
32 cm.
SUPERIOR GLUTEAL ARTERY PERFORATOR FLAP
145
Figure 4–17
Flap design and Doppler detection.
1. Gluteux maximus m.
2. Superior gluteal a.
3. Super cial branch of superior gluteal a.
4. Deep branch of superior gluteal a. and superior
gluteal n.
5. Gluteus medius m.
6. Tensor fasciae latae m.
7. Myocutaneous perforators
Elevation of Upper Portion and
Perforator Identi cation (Fig. 4–18)
Elevation begins from the laterosuperior portion of the
ap. As this portion is raised, the gluteus m edius can
be identi ed by its m uscle bers coursing vertically.
Once the upper border of the gluteus m axim us is
reached, dissection should be in the plane between the
deep fascia and the m uscle, taking care to search out
and preserve the perforators as vascular bundles
em erging from the m uscle, penetrating the deep fascia,
and im m ediately entering the subcutaneous fat of the
flap. More attention should be paid to the area in which
the perforator was detected by Doppler flow m eter
preoperatively.
Lower Portion Elevation (Fig. 4–19)
As soon as an adequate perforator bundle is found,
ap elevation is continued, w ith care to protect the
perforator bundle from avulsion injury. During flap
elevation, m ore perforators m ay be preserved for
further selection.
146
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–18
Upper portion elevation and perforator identi cation.
1. Gluteus maximus m.
5. Gluteus medius m.
6. Tensor fasciae latae m.
7. Myocutaneous perforators
Figure 4–19
Lower portion elevation.
1. Gluteus maximus m.
7. Myocutaneous perforators
Intramuscular Dissection plus Pedicle
Dissection (Fig. 4–20)
The perforator bundles should be dissected by using the
loupe or under the operating microscope. If there are
two or more selected perforators, they are usually situ-
ated in the same cleavage plane as the muscle bers:
Splitting the muscle for development of the exposure
and dissection of the perforator bundles will not dam-
age the muscle bers extensively. After ligation of the
m uscular branches to the upper part of the gluteus
maxim us, the perforator bundles will converge to the
super cial branch of the superior gluteal vessels under-
neath the muscle. Dissection can be continued on the
super cial branch for 3 cm, to reach the bifurcation
with the deep branch, near the em ergence of the supe-
rior gluteal vessels from the greater sciatic foram en
above the piriformis. At this point, the vascular pedicle
length can be 8 cm. The nal dissection near the bifur-
cation with the deep branch underneath the muscle may
be very dif cult because of the deeply situated vascular
plexus formed by its multiple branches.
Once the recipient site is prepared, the superior
gluteal vessels are ligated, and the vascular pedicle of
the skin ap is readily removed through the cleavage of
the muscle. The S-GAP ap is now ready for transfer.
SUPERIOR GLUTEAL ARTERY PERFORATOR FLAP (S-GAP FLAP)
147
Figure 4–20
Intramuscular dissection plus pedicle dissection.
1. Gluteus maximus m.
2. Superior gluteal a.
3. Super cial branch of superior gluteal a.
4. Deep branch of superior gluteal a. and superior gluteal n.
5. Gluteus medius m.
6. Tensor fasciae latae m.
7. Myocutaneous perforators
INFERIOR GLUTEAL ARTERY
PERFORATOR FLAP (I-GAP FLAP)
This skin ap is one of the m ost recently developed
perforator aps. It excludes the m uscle underneath,
maxim ally decreasing postoperative morbidity. Mean-
while, its pedicle length is signi cantly extended for
convenience in m icrosurgical revascularized transfer.
Even though there are very lim ited case reports (only
for breast reconstruction), it could potentially becom e a
popular ap, owing to its advantages.
Flap Design and Doppler
Detection (Fig. 4–21)
The inferior gluteal crease is m arked as the lower
border of the ap, and a transverse elliptical ap is then
designed. Generally, the size of the ap is 22 cm long
(along the transverse axis) and 10 cm wide; the defect
after harvesting can be directly closed.
A line is drawn from the posterior superior iliac
spine to the tuberosity of the ischium. The midpoint is
marked as the emergence of the inferior gluteal artery
148
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–21
Flap design and Doppler
detection.
1. Gluteus maximus m.
2. Musculocutaneous perforator bundle
3. Inferior gluteal a.
4. Sciatic n.
from the pelvis. Beginning laterally within the skin
territory of the ap, a Doppler owm eter is used to nd
the cutaneous perforators from the inferior gluteal
artery; one or two predominant (the loudest) points are
marked for intraoperative guidance.
Flap Elevation and Perforator
Identi cation (Fig. 4–22)
An incision is made following the line proposed for the
ap, through the subcutaneous tissue and deep fascia,
to reach the surface of the muscle. If increased volume
is required for the ap, the subcutaneous tissue is
divided by beveling. A dissection is performed in the
infrafascial layer, carefully distinguishing the cutaneous
perforator from the muscle, while the ap is elevated
gradually from lateral to medial.
INFERIOR GLUTEAL ARTERY PERFORATOR FLAP (I-GAP FLAP)
149
Figure 4–22
Flap elevation and perforator identi cation.
1. Gluteus maximus m.
2. Musculocutaneous perforator bundle
150
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–24
Completion of ap elevation.
1. Gluteus maximus m.
2. Musculocutaneous perforator bundle
3. Inferior gluteal a.
4. Sciatic n.
Figure 4–23
Intramuscular dissection.
1. Gluteus maximus m.
2. Musculocutaneous perforator bundle
3. Inferior gluteal a.
4. Sciatic nerve
Intramuscular Dissection (Fig. 4–23)
As soon as the dom inant perforator is identi ed, an
intram uscular dissection is perform ed through the
gluteus m axim us m uscle obliquely downward to the
inferior gluteal vessels. The branches to the m uscle
substance are ligated, and the perforator bundle is freed
from the m uscle until the m ain trunk of the inferior
gluteal vessels is reached.
Completion of Flap
Elevation (Fig. 4–24)
The medial portion of the ap is raised, and the inferior
gluteal bundle is dissected free. Generally, the pedicle
length can be from 7 cm to 13 cm. The sciatic nerve lies
beneath the gluteus m axim us m uscle in the adipose
tissue near the inferior gluteal vessels. Attention should
be paid not to injure it, especially when retractors are
applied in the cleavage of the m uscle.
RECIPIENT SITE EXPOSURE
Superior Gluteal Artery
Incision (Fig. 4–25)
An incision is m ade from the posterior superior iliac
spine, along the iliac crest for 7 cm , turning down-
ward toward the apex of the greater trochanter of the
femur.
RECIPIENT SITE EXPOSURE
151
Figure 4–25
Incision.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Iliac crest
4. Gluteal a.
5. Super cial branch
6. Deep branch
7. Gluteal n.
8. Gluteus minimus m.
9. Piriformis m.
Exposure of Septum between Gluteus
Maximus and Medius (Fig. 4–26)
The upper lateral edge of the gluteus maximus (1) is
identi ed, and its origin on the posterior gluteal line of
the ilium is then detached.
152
II.4 LOWER EXTREMITY: GLUTEAL REGION
Figure 4–26
Exposure of septum between
gluteus maximus and medius.
1. Gluteus maximus m.
2. Gluteus medius m.
3. Iliac crest
Approach to the Vessel (Fig. 4–27)
Dissection proceeds between the glutei m axim us (1)
and m edius (2) m uscles. The m uscle flap is turned
over and down; the super cial branch of the superior
gluteal artery (5) is visible on its deep surface. Retract-
ing the m uscle ap inferiorly, the em ergence of the
super cial branch can be identi ed between the glu-
teus m edius (2) and the piriform is (9), near the junc-
tion of the upper and m iddle thirds of the line joining
the posterior superior iliac spine to the apex of the
greater trochanter of the fem ur.
Retracting the gluteus m edius superiorly, further
dissection is performed to expose the main trunk of the
superior gluteal artery (4) and the bifurcation with the
deep branch (6) above the piriform is (9). The superior
gluteal nerve (7) accompanies the deep branch of the
superior gluteal artery (6) to supply the gluteus medius
(2) and minimus (8) muscles.
RECIPIENT SITE EXPOSURE
153
Figure 4–27
Approach to the vessel.
1. Gluteus maximus m.
2. Gluteus medius m.
4. Gluteal a.
5. Super cial branch
6. Deep branch
7. Gluteal n.
8. Gluteus minimus m.
9. Piriformis m.
BIBLIOGRAPHY
Allen RJ, Tucker C Jr. Superior gluteal artery perforator
free ap for breast reconstruction. Plast Reconstr Surg
1995;95:1207
Blondeel PN. The sensate free superior gluteal artery
perforator (S-GAP) ap: a valuable alternative in autol-
ogous breast reconstruction. Br J Plast Surg 1999;52:185
Breidahl AF, Johnstone BR. Innervated posterior thigh
ap for defects of the sole. Plast Reconstr Surg 1995;
95:747
Buchanan DL, Agris J. Gluteal plication closure of sacral
pressure ulcers. Plast Reconstr Surg 1983;72:49
Fujino T. Microvascular free transfer of a gluteal muscu-
locutaneous ap. In: Strauch B, Vasconez LO, Hall-Findlay
E, eds. Grabb’s Encyclopedia of Flaps. Vol 2. Boston:
Little, Brown; 1990:1319ff
Fujino T, Harashin T, Aoyagi F. Reconstruction for apla-
sia of the breast and pectoral region by m icrovascular
transfer of a free ap from the buttock. Plast Reconstr
Surg 1975;56:178
Germann G, Cedidi C, Petracic A, et al. The partial gluteus
maximus musculocutaneous turnover ap: an alterna-
tive concept for simultaneous reconstruction of com-
bined defects of the posterior perineum/sacrum and the
posterior vaginal wall. Br J Plast Surg 1998;51:620
Gould WL, Mentero N, Cukic J, et al. The “split” gluteus
maxim us m usculocutaneous ap. Plast Reconstr Surg
1994;93:330
Guelinckx PJ, Sinsel NK, Gruwez JA. Anal sphincter
reconstruction with the gluteus m axim us m uscle:
anatom ic and physiologic considerations concerning
conventional and dynamic gluteoplasty. Plast Reconstr
Surg 1996;98:293
Hagerty RC, Gould WL. The split gluteus m axim us
muscle turnover ap. Plast Reconstr Surg 1995;96:1459
Huang G-K, Hu R-Q, Hua M, et al. Microvascular free
transfer of iliac bone based on the deep superior
branches of the superior gluteal vessels. Plast Reconstr
Surg 1985;75:68
Hurwitz DJ. Closure of a large defect of the pelvic
cavity by an extended compound myocutaneous ap
based on the inferior gluteal artery. Br J Plast Surg
1980;33:256
Hurwitz DJ, Swartz WM, Mathes SJ. The gluteal thigh
ap: a reliable, sensate ap for the closure of buttock
and perineal wounds. Plast Reconstr Surg 1981;68:521
Koshim a I, Moriguchi T, Soeda S, et al. The gluteal
perforator-based ap for repair of sacral pressure
sores. Plast Reconstr Surg 1993;91:678
Le-Quang C. Two new free aps developed from aes-
thetic surgery, II: the inferior gluteal ap. Aesthetic
Plast Surg 1980;4:159
Mathes SJ, Nahai F. Clinical Atlas of Muscle and Muscu-
locutaneous Flaps. St. Louis: CV Mosby; 1979:94–98
Mialhe C, Brice M. A new compound osteo-myocutaneous
free ap: the posterior iliac artery ap. Br J Plast Surg
1985;38:30
Orgel MG, Kucan JO. A double-split gluteus maxim us
m uscle ap for reconstruction of the rectal sphincter.
Plast Reconstr Surg 1985;75:62
Patel AC, Kuzon WM Jr. Coverage of an ischial pressure
ulcer with an interpolated contralateral posterior thigh
fasciocutaneous ap. Br J Plast Surg 2001;54:547
Rajacic N, Gang RK, Dashti H, Behbehani A. Treatment of
ischial pressure sores with an inferior gluteus maximus
m usculocutaneous island ap: an analysis of 31 aps.
Br J Plast Surg 1994;47:431
Ram irez OM, Hurwitz DJ, Futrell JW. The expansive
gluteus maximus ap. Plast Reconstr Surg 1984;74:757
Ram irez OM, Orlando JC, Hurwitz DJ. The sliding
gluteus maximus myocutaneous ap: its relevance in
am bulatory patients. Plast Reconstr Surg 1984;74:68
Reddy DM, Koul AR. Free split iliac-bone ap transfer
based on the superior gluteal vessels: anatomy and
case reports. J Reconstr Microsurg 1997;13:229
Rubayi S, Doyle BS. The gluteus maximus muscle-splitting
myocutaneous ap for treatment of sacral and coccygeal
pressure ulcers. Plast Reconstr Surg 1995;96:1366
Rubin JA, Whetzel TP, Stevenson TR. The posterior
thigh fasciocutaneous ap: vascular anatomy and
clinical application. Plast Reconstr Surg 1995;95:1228
Sche an M, Nahai F, Bostwick J III. Gluteus m axim us
island musculocutaneous ap for closure of sacral and
ischial ulcers. Plast Reconstr Surg 1981;68:533
Shaw WW. Breast reconstruction by superior gluteal
m icrovascular free aps without silicone im plants.
Plast Reconstr Surg 1983;72:490
Verpaele AM, Blondeel PN, Van Landuyt K, et al. The
superior gluteal artery perforator ap: an additional
tool in the treatment of sacral pressure sores. Br J Plast
Surg 1999;52:385
Walton RL, Hurwitz DJ, Bunkis J. Gluteal thigh ap for
reconstruction of perineal defects. In: Strauch B,
Vasconez LO, Hall-Findlay E, eds. Grabb’s Encyclopedia
of Flaps. Vol 3. Boston: Little, Brown; 1990:1455ff
Yano K, Matsuo Y. Combined latissim us dorsi musculo-
cutaneous ap and free superior gluteal artery skin
ap. Br J Plast Surg 2000;53:529
154
II.4 LOWER EXTREMITY: GLUTEAL REGION
GROIN FLAPS
Anatomy of Groin Flaps
(Fig. 5–1)
The skin territory of groin aps consists of
the upper portion of the thigh, the lower
portion of the abdomen, and the iliac area.
The blood supply is provided by an arterial
network that converges m ainly from the
following ve arteries: super cial circum-
ex iliac artery (SCIA) (3), super cial infe-
rior epigastric artery (SIEA) (6), fourth
lumbar artery, deep circum ex iliac artery,
and superior gluteal artery. The rst three
are discussed in this section and the latter
two in the section on the vascularized iliac
bone graft.
5
Groin Region
Figure 5–1
Anatomy of groin aps.
1. Femoral a. and v.
2. Saphenous v.
3. Super cial circum ex iliac a (SCIA)
4. Super cial branch of SCIA
5. Deep branch of SCIA
6. Super cial inferior epigastric a. (SIEA)
7. Lateral femoral cutaneous n.
8. Sartorius m.
9. Super cial circum ex iliac v. (SCIV)
10. Super cial inferior epigastric v. (SIEV)
11. External pudendal a. and v.
Figure 5–2
Variations of the SCIA and SIEA (see text for details).
156
II.5 LOWER EXTREMITY: GROIN REGION
The SCIA (3) arises from the anterolateral aspect of
the femoral artery (1), 2.5 cm below the inguinal liga-
m ent, and runs toward the anterior superior iliac spine
(ASIS). It divides into two branches less than 1.5 cm
after its origin.
The super cial branch (4) runs into the subcuta-
neous level im m ediately and parallel to the inguinal
ligament 2 cm below it. This branch, with an average
diameter of 0.8 mm , is absent in 14% of cases.
The deep branch (5) runs beneath the deep fascia
parallel to the inguinal ligam ent and 1.5 cm below it.
This branch crosses the lateral fem oral cutaneous
nerve (7), gives off branches to the sartorius, and then
penetrates the deep fascia at the lateral border of the
sartorius m uscle, continuing subcutaneously and giv-
ing off sm all branches to the iliac crest. The deep
branch, with an average diam eter of 1.0 m m , appears in
100% of cases.
The superficial and deep branches are of about
equal importance in supplying the ap. Their com m on
stem averages 1.5 cm in length and 1.5 m m in
diameter.
The SIEA (6) usually arises from the front of the
femoral artery (1), 1 cm below the inguinal ligament.
Piercing the cribriform fascia, it ascends in front of the
ligament and between the two layers of the super cial
fascia of the abdominal wall toward the umbilicus. The
average diameter of this artery is 1.4 mm.
The follow ing variations of the SCIA and SIEA are
illustrated in Fig. 5–2:
A. A com m on origin in 48% of cases, w ith a m ean
diam eter of 1.4 mm (range: 0.8 to 3.0 m m).
B. A large SCIA w ithout an SIEA in 35% of cases, w ith
a m ean diam eter of 1.4 m m (range: 0.8 to 3.0 m m ).
C. Separate origins in 17% of cases, w ith a m ean
diam eter of 1.1 mm (range: 0.8 to 1.8 mm).
Venous Drainage
There are two drainage system s in this area. The dom -
inant venous system is the super cial cutaneous veins
involving the super cial circum ex iliac vein (SCIV)
(9) and the super cial inferior epigastric vein (SIEV)
(10). The deep veins, such as the venae com itantes
of these arteries, serve as an additional drainage
system . The average diam eter of the venae com itantes
is 1.1 m m .
Regarding the super cial venous system, in 50 to
60% of cases, the SCIV and SIEV form a saphenous bulb
(common trunks) with an average diameter of 2.5 m m,
ranging from 1.2 to 5.0 m m. Although they drain into
the saphenous vein separately, their average diameter
is 2.0 mm.
GROIN FLAPS
157
The groin ap was one of the earliest aps used in micro-
surgical tissue transplantation. There have been m any
cases reported in the literature. However, as a result of
variation in vasculature, sm all caliber and short length
of the arterial pedicle, dif culty in harvesting the ap,
and an awkward and cramped position for microvascu-
lar anastomoses, the dominant place of the groin ap
has gradually given way to subsequent and more cur-
rently used donor sites. However, according to recent
references, the groin ap is still useful and deserves
consideration in reconstructive microsurgery.
This donor site can provide a greater am ount of
skin coverage. The defect can usually be closed
primarily with minimal morbidity and the donor scar is
quite inconspicuous.
The m edial portion of the ap is rather bulky and
hairy. The m odified groin flap provides som ew hat
thinner and m ore hairless tissue and a longer vascular
pedicle. But the procedure becom es m ore com pli-
cated and risky, and the available area for the flap
decreases.
The groin ap is applied mostly for coverage of soft
tissue defects in the head and neck, the trunk, and the
upper and lower extrem ities. According to som e
current literature, it also can be used in reconstruction
of the breast or tongue.
For a reliable vascularized iliac bone graft, the
osteocutaneous ap based on the deep circum ex iliac
artery (DCIA) is recommended, rather than one based
on the SCIA.
Innervation of the cutaneous portion of these aps
comes segmentally from the cutaneous branches of the
12th thoracic nerve and one iliohypogastric nerve. A truly
sensible ap in this area is therefore dif cult to achieve.
COMMENT AND INSIGHTS
Figure 5–3
Flap design.
1. Deep branch of SCIA
2. ASIS
3. Sartorius m.
4. Lateral femoral cutaneous n.
5. Femoral a. and v.
6. Saphenous v.
7. SCIV
8. SCIA
9. Super cial branch of SCIA
10. SIEV
SUPERFICIAL CIRCUMFLEX ILIAC (SCIA)
FLAP (OR ILIOFEMORAL FLAP)
Flap Design (Fig. 5–3)
The surface anatomy of the SCIA is determined by a line
drawn from a point on the femoral artery 2.5 cm below
the inguinal ligament to the ASIS. Although it is advised
that the central axis of the ap be designed a little
higher than this line, it can be expanded to the angle of
the scapula.
The inferior border of the ap is drawn 5 cm below
and parallel to the inguinal ligam ent, and an S-shaped
median border lies just over the femoral artery or 1 to 2 cm
lateral to it. Superior and lateral borders are designed to
meet the requisite dimensions. The common size of this
ap is 10
20 cm, and the largest size reported is up to
22
31 cm .
Two techniques can be employed in ap elevation.
158
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–4
Elevation of the
lateral edge of the ap.
1. Deep branch of SCIA
2. ASIS
Lateral-to-Medial Procedure
Elevation of the Lateral Edge
of the Flap (Fig. 5–4)
The lateral portion of the ap is elevated super cially to
the deep fascia until the ASIS (2) is reached. Meticulous
dissection is necessary at the lateral border of the sarto-
rius muscle to insure inclusion of the SCIA (1).
SUPERFICIAL CIRCUMFLEX ILIAC (SCIA) FLAP (OR ILIOFEMORAL FLAP)
159
Figure 5–5
Identi cation and
dissection of SCIA.
1. Deep branch of SCIA
2. ASIS
3. Sartorius m.
4. Lateral femoral cutaneous n.
Identi cation and Dissection of
the SCIA (Fig. 5–5)
A branch to the muscle should be ligated to allow the
super cial circum ex iliac vessel and a patch of the
fascia of sartorius (3) to be attached to the ap. Dissection
then proceeds through areolar tissue over the fascia of
the iliacus m uscle along the pulsative course of the
SCIA (1), to the origin of the femoral vessels. The origin
of the SCIA is followed, and the SIEA can also be found
and dissected.
160
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–6
Complete ap elevation.
1. Deep branch of SCIA
3. Sartorius m.
4. Lateral femoral cutaneous n.
5. Femoral a. and v.
6. Saphenous v.
7. SCIV
9. Super cial branch of SCIA
Complete Flap Elevation (Fig. 5–6)
After the procedures just described have been performed,
the medial border of the ap is incised to expose the
super cial cutaneous vein. The SIEV and SCIV (7) are
identi ed and preserved.
The groin ap may be isolated on two arteries and
several veins. However, one artery and one vein that
appear optim al for m icrovascular anastom oses are
nally selected.
SUPERFICIAL CIRCUMFLEX ILIAC (SCIA) FLAP (OR ILIOFEMORAL FLAP)
161
Figure 5–7
Dissection on medial
side.
3. Sartorius m.
5. Femoral a. and v.
6. Saphenous v.
7. SCIV
10. SIEV
Medial-to-Lateral Procedure
Dissection on Medial Side (Fig. 5–7)
Dissection is started in the m edial S-shaped incision,
the base of the ap. The saphenous vein (6) and femoral
artery and vein (5) are identi ed and dissected from
below and m edially. Further dissection reveals the
variations of the SCIV (7) and SIEV (10).
162
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–8
Identi cation of the
SCIA.
3. Sartorius m.
5. Femoral a. and v.
6. Saphenous v.
7. SCIV
8. Super cial branch of SCIA
Identi cation of the SCIA (Fig. 5–8)
The origins of the SCIA (8) and SIEA are identi ed
following the course of the femoral vessels (5). After the
dissection of the m edial aspect of the ap, the lateral
portion is then elevated until the lateral border of the
sartorius (3) is reached. Here, the deep fascia should be
divided and turned medially with the ap, thus avoiding
damage to the SCIA (8). The groin ap is isolated.
The obtained vascular pedicle length in both proce-
dures just described can be less than 1 cm for the arteries
and 2 to 3 cm for the super cial veins.
SUPERFICIAL CIRCUMFLEX ILIAC (SCIA) FLAP (OR ILIOFEMORAL FLAP)
163
Figure 5–9
Flap design.
1. Femoral a. and v.
2. SCIA
3. SCIV
4. Saphenous v.
ILIAC FLAP
The iliac ap is a m odi ed groin ap and is designed for
the purpose of increasing vascular pedicle length and
for decreasing the thickness of the m edial portion of
the ap.
Flap Design and Incision (Fig. 5–9)
The medial margin of the ap lies lateral to the femoral
triangle (the m edial border of the sartorius). To ex-
plore the vessels, the m edial incision is T-shaped, lying
on its side. The cross limb and stem of the T correspond
to the m edial m argin of the ap and the surface
anatomy of the SCIA.
164
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–10
Identi cation of SCIA.
1. Femoral a. and v.
2. SCIA
3. SCIV
4. Saphenous v.
Identi cation of the SCIA (Fig. 5–10)
The technique of elevating this ap is sim ilar to the
m edial-to-lateral procedure. Both the super cial and
deep branches of the SCIA (2) are preserved in this ap
as much as possible. The vascular pedicle can reach a
length of 4 cm.
ILIAC FLAP
165
Figure 5–11
Flap and bony segment.
1. Femoral a. and v.
2. Saphenous v.
3. SCIA
4. SCIV
5. Sartorius m.
6. Iliac bone
OSTEOCUTANEOUS GROIN FLAP
(BASED ON THE SCIA)
Flap and Bony Segment (Fig. 5–11)
The skin ap is designed as the groin ap already
described, and the proposed segm ent of bone is drawn
on the iliac crest.
166
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–12
Osteotomy
and ap elevation.
1. Femoral a. and v.
2. Saphenous v.
3. SCIA
4. SCIV
5. Sartorius m.
6. Iliac bone
Osteotomy and Flap Elevation
(Fig. 5–12)
The lateral-to-m edial procedure is used. The ap is
raised around the proposed iliac bone (6) segm ent,
keeping the skin ap, fascia, and iliac crest intact. The bony
attachment of the external and internal oblique above and
of the tensor fasciae latae (TFL) below are divided, leaving
a 1-cm fringe of m uscle attached to the bone. If the
bone segment includes the ASIS, a centimeter of sartorius
muscle (5) and the inguinal ligament should be included
in the graft.
During this procedure, attention m ust be paid
to identifying and preserving the SCIA (3) in the ap at
the lateral border of the sartorius, before dividing the
bone. Bone segments have been reported with sizes of
6
1 cm and 8
3 cm.
OSTEOCUTANEOUS GROIN FLAP (BASED ON THE SCIA)
167
Figure 5–13
Flap design and upper incision.
1. External oblique m. or aponeurosis
2. Internal oblique m.
3. Areolar tissue
4. Inguinal ligament
5. Femoral a. and v.
6. SCIA
7. SCIV
COMPOSITE GROIN FLAP WITH
“TENDON” TRANSFER
Flap Design and Upper Incision
(Fig. 5–13)
The external oblique aponeurosis is nourished from the
SCIA through the loose areolar tissue on its surface
where there is one of the anastom otic zones between
the deep and super cial systems of vessels.
168
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–14
Exposure of the aponeurosis.
1. External oblique m. or aponeurosis
2. Internal oblique m.
Exposure of the Aponeurosis
(Fig. 5–14)
The lateral and superior edges of the groin ap are
incised and the lmy, mobile layer of areolar tissue is
identi ed on the surface of the external oblique
aponeurosis (1).
COMPOSITE GROIN FLAP WITH “TENDON” TRANSFER
169
Figure 5–15
Elevation of the
aponeurosis.
1. External oblique m. or aponeurosis
2. Internal oblique m.
Elevation of the Aponeurosis
(Fig. 5–15)
The areolar layer is incised 6 cm above and parallel to
the inguinal ligam ent and gently peeled downward
from the aponeurosis for a short distance. Then, the
aponeurosis is divided in the direction of its bers along
the upper border of the intended graft. Vertical cuts are
made at both ends for a distance and shape following
the tendon caliber and length needed at the recipient
site. Usually, repair of an ordinary extensor tendon
needs an incision of 1.5 cm; repair of a tibialis anterior
tendon, 2.0 cm; and of an Achilles tendon, 4 to 5 cm.
The strip of the aponeurosis is separated from the
underlying internal oblique m uscle, and its lower
border is incised from its deep surface. Then the areolar
tissue is carefully dissected with this tendinous portion
from the other part of the aponeurosis until the in-
guinal ligam ent is reached. The graft is attached along
its length to the undersurface of the ap by a 4-to-5-cm
“keel” of areolar tissue.
170
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–16
Flap completion and “tendon” preparation.
1. External oblique m. or aponeurosis
2. Internal oblique m.
3. Areolar tissue
4. Inguinal ligament
5. Femoral a. and v.
6. SCIA
7. SCIV
Flap Completion and “Tendon”
Preparation (Fig. 5–16)
The groin ap with the “tendon” graft (1) is isolated on
the SCIA (6), following either the lateral-to-medial or
m edial-to-lateral approach already described. The
aponeurosis strip is then tubed along its length with
invagination of the cut edge.
COMPOSITE GROIN FLAP WITH “TENDON” TRANSFER
171
Figure 5–17
Flap design.
1. Femoral a. and v.
2. Saphenous v.
3. SIEA
4. SIEV
5. SCIA
SUPERFICIAL INFERIOR EPIGASTRIC
(SIEA) FLAP (OR LOWER
ABDOMINAL FLAP)
Flap Design (Fig. 5–17)
The axis of this ap is the line between the umbilicus
and the femoral artery. The upper limit of the ap is at
the level of the umbilicus; the lower limit, 2 to 4 cm
below the inguinal ligament; medially, to the midline of
the abdomen; and laterally, up to the ASIS.
172
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–18
Identi cation of SIEV
and SIEA.
1. Femoral a. and v.
2. Saphenous v.
3. SIEA
4. SIEV
5. SCIA
Identi cation of SIEV and SIEA
(Fig. 5–18)
The lower-to-upper procedure is applied to raise the
ap. Using a Y-shaped incision on the lower part of the
flap, the SIEV (4) and SCIV are exposed and then, following
the fem oral artery (1), the SIEA (3) and SCIA (5) are
identi ed.
SUPERFICIAL INFERIOR EPIGASTRIC (SIEA) FLAP (OR LOWER ABDOMINAL FLAP)
173
Figure 5–19
Flap elevation.
1. Femoral a. and v.
2. Saphenous v.
3. SIEA
4. SIEV
5. SCIA
Flap Elevation (Fig. 5–19)
The upper part of the ap is elevated at the level
super cial to the aponeurosis of the external oblique
abdominis.
174
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–20
Anatomy of the
fourth lumbar artery.
1. Latissimus dorsi m.
2. External oblique m.
3. Inferior lumbar trigone
4. Fourth lumbar a.
5. Ventral branch
6. Dorsal branch
7. Iliac bone
FOURTH LUMBAR ARTERY ILIAC FLAP
Anatomy (Fig. 5–20)
The fourth lumbar artery (4) arises from the posterolat-
eral aspect of the abdom inal aorta and runs behind the
psoas m ajor m uscle. At its m edial border, the artery
divides into dorsal and ventral branches (5,6). The
dorsal branch passes between the sacrospinal and
quadrate lumbar muscles, emerging in the inferior lum-
bar trigone (3) that is formed by the lateral margin of
the latissimus dorsi (1), the posterior free border of the
external oblique (2), and the iliac crest (7). It runs
lateroinferiorly in the subcutaneous tissue to supply
the skin and bone of the iliac area.
The emerging point is located 6.5 cm lateral to
the back midline and 0.8 cm above the iliac crest. The
diameter of the fourth lumbar artery is 0.8 to 1.8 mm,
and the diam eter of the venae com itantes is 0.8 to
2.4 mm at the inferior lumbar trigone.
FOURTH LUMBAR ARTERY ILIAC FLAP
175
This donor site is rarely used in clinical microsurgery,
but there are still some scarce case reports in the recent
decade. It also can be com bined with a segment of the
iliac crest to become an osteocutaneous composite ap
transfer. It will usually not result in any functional or
cosmetic problem after harvesting.
COMMENT AND INSIGHTS
Figure 5–21
Flap design.
1. Latissimus dorsi m.
2. External oblique m.
3. Inferior lumbar trigone
4. Fourth lumbar a.
5. Ventral branch
6. Dorsal branch
7. Iliac bone
Harvesting Technique
Flap Design (Fig. 5–21)
The emerging point of the dorsal branch of the fourth
lum bar vessel is m arked on the lateral border of the
sacrospinal muscle and just above the iliac crest. The
axis of the ap goes along the iliac crest. The underlying
iliac crest can be raised with the ap as an osteocuta-
neous ap.
Maximum ap size has been reported with an area
of 9
11 cm and bone of 8
3
1 cm.
176
II.5 LOWER EXTREMITY: GROIN REGION
Figure 5–22
Identi cation of fourth lumbar
vessels.
1. Latissimus dorsi m.
6. Dorsal branch
7. Iliac bone
Identi cation of Fourth Lumbar
Vessels (Fig. 5–22)
Making an 8-cm-long incision 1 cm medial to the lateral
border of the sacrospinal muscle (1), the dorsal branch
of the fourth lumbar vessel (6) is identi ed in the infe-
rior lumbar trigone.
FOURTH LUMBAR ARTERY ILIAC FLAP
177