nghiên cứu giải phẫu ứng dụng động mạch mũ đùi ngoài trên người việt trưởng thành bản tóm tắt tiếng anh

BACKGROUND
With the rapid development of micro plastic surgery to bring normal
life to patients, domestic and foreign plastic surgeons have studied and
developed a series of flaps to reconstruct defects or flaws on the body.
Particularly, the anterolateral thigh flap, which can be used for many areas,
is suitable for undertaking this role and is currently being studied for
several other applications.
However, due to incomplete understanding of the vascular anatomy of
this area, some surgeons still hesitate to use this flap. Classical anatomical
textbooks described the lateral circumflex femoral artery has a common
trunk which is separated from the deep femoral artery, then it gives off the
ascending branch, horizontal branch and descending branch to supply
blood to the anterolateral femoral region. Foreign surgeons have a general
comment that this artery has many anatomical variants. Ascending
branches, horizontal branches, and descending branches give off many
subcutaneous, or muscular or direct perforators to the skin. Anatomical
characteristics of those perforators vary among races, due to changes of the
origin of branches of the lateral circumflex femoral artery, so clinically, it
is necessary to determine the location of those perforators on the skin.
In Vietnam, there have been a number of studies mentioned the lateral
circumflex femoral artery and its branches; but no studies were be able to
determine the branching of this artery as a coherent and complete
classification. The use of the anterolateral thigh flap was interrupted since
2005, due to difficulties in identifying the perforators of the flap, but then
the use of this flap is increasingly deployed in many hospitals grace to
some applicative studies. However, there is no systemic research about the
anterolateral thigh flap in clinical, as well as its applications.
We therefore conducted the “Applied anatomy of the lateral
circumflex fermoral artery in Vietnamese cadavers”; to achieve these
following objectives:
1. Describe the anatomical characteristics of the lateral circumflex

femoral artery in the Vietnamese adult.
2. Describe the anatomical characteristics of the perforators of the
lateral circumflex femoral artery in the Vietnamese adult.
New contributions of the thesis:
- Detailed describes an adequate anatomical characteristics of lateral
circumflex femoral artery, provides principles for determining and
mapping the anatomical variants of 13 types of division, categorized into 5
main groups.
- Provides principle to divide the femoral baseline into 8 equal
divisions, for easier clinical usage, and recommends a circle of 5cm radius
to identify perforators of the flap (100% found at least one perforator) and
those perforators commonly found in the division of 2/8 and 6/8.
Layout of the thesis:
The contents of the thesis were presented in 122 pages, included 4
main chapters; background 2 pages, Chapter 1 - Overview 30 pages,
Chapter 2 - Subjects and Methods 14 pages; Chapter 3 – Results 47 pages
(13 Tables, 10 charts and 39 pictures), Chapter 4 - Discussion 26 pages;
Conclusion 2 pages, Recommendations 1 page. 125 References (17
Vietnamese documents, 107 documents in English and 1 German
document).
Chapter 1 – OVERVIEW
1.1. Characteristic anatomical the lateral circumflex femoral artery
The lateral circumflex femoral artery often origins from deep femoral
artery, a few from the femoral artery, divides into three branches:
ascending, horizontal and descending branch.
Table 1.1. Comparison of the frequency of lateral circumflex femoral
artery among authors.
Author Year Subject From DFA From FA
Dixit 2001 Cadavers 83,3% 16,7%
Fukuda 2005 CT films 78,6% 21,4%

Choi 2007 Cadavers 86,8% 13,2%
Tansatit 2008 Cadavers 56,7% 43,3%
Uzel 2008 Cadavers 77,3% 22,7%
Prakash 2010 Cadavers 81,3% 18,7%
Studies of the LCFA have shown that this system is very complex and
diverse in anatomical changes.
Table 1.2. Comparison the origins of the lateral circumflex femoral
artery among authors.
Imag
e
Choi Bergman
Pradabsu
k
Wen Tai
Type I Type 1 Type C Type I/II Type
A
Type II Type 1 Type E Type III Type
D
Type III Type 1/6 Type A Type VI Type
C
Type IV Type 2 Type B Type IV Type
B
Classic literatures have not explicitly and particularly recognized the
anatomical variations of the lateral circumflex femoral artery, each author
has their own classification and naming rules, depending on race and the
sample size of the study, we could not agree on the name of LCFA. In
Vietnam there is not much research on the anatomy of the LCFA and its
tributaries.
1.2. Anatomical characteristics of the perforators from branches of the
LCFA

The perforators of the anterolateral thigh are mostly originated from
the descending branch of the LCFA but there are also other variations, they
can arise from DFA or FA.
In 1999, Luo S.K. classified those perforators into four types: (1)
perforators type M come from the descending branch of LCFA, penetrate
the vastus lateralis muscle, and supply blood to the skin, this is the most
common type; (2) perforators type S travel between the septum of the
vastus lateralis muscle and the rectus femoralis muscle, supply blood
directly to the skin; (3) perforators type D derived from the horizontal
branch of LCFA or beyond the origins of the descending branch of the
LCFA, penetrate the iliotibial tract and go directly to the skin, (4) the small
perforators, visible on the surface of the vastus lateralis mucle. His later
research found that the ratio between perforators type M and type S is 4:1.
1.3. Distribution on the skin of perforators from branches of LCFA.
According to Yu P. 93% population have one perforator B around the
midpoint of the femoral baseline, perforator A and C are upper or lower ±
5cm from point B on the baseline. Hallock G.G. B also defined that B is
the midpoint of the femoral baseline, almost all of perforators are found
within the circle of 3cm radius around the point B, A and C are 5 - 8cm
distal from B on the baseline. Wolff found there are almost always a
dominant perforator enters the skin within the circle of 4cm radius.
Tansatit T. noted that perforators are frequently appeared in the middle
third of the thigh, the first perforator is in the middle third of the thigh ,
near to the anterior superior iliac spine than the rest of perforators. Choi
found that perforators often gather from the portion 4/10 to 8/10 of the
femoral baseline. Yu also shown that perforators distribute mainly from the
portion 3/10 to 7/10.
According to Luo S.K. 90% have at least one perforator in a circle of
3cm radius and 78% of perforators is located in the laterolower quarter of
this circle. Wolff always found at least one perforator in a circle of 4cm

radius. Kavita noted that 65% of perforators are located within a circle of
5cm radius and 96% have at least one perforator in this circle. Kuo Y.R.
reported that in 92% the dominant perforator is located in a circle of 5cm
radius. Choi S.W. proposed an expansion of radius to 6cm, then there is
85.6% of perforators in the cirlce.
1.4. Anatomical characteristics of the perforator flaps based on
branches of the LCFA.
Anterolateral thigh flap is essentially a perforator flap, mainly
perforators type M, perforators type S are from 18 to 48%.
1.5. The clinical applications of the anterolateral thigh flaps based on
the perforators of the LCFA
The anterolateral thigh flap has a wide usage and application zones. It
can be used in the head and neck to cover cheek defect, to pad flat surface
or to create facial contour, to reconstruct mouth flour and esophagus. In
the chest, it is also used to create the breast after mastectomy. In the groin -
abdomen – genital areas, flap can be used as a downstream island flap to
reconstruct defects of the groin and abdominal region, vaginal and perineal
defects or to reconstruct the penis. In the upper limb flap is used as a
“perforator bridge” to reconstruct the palm and fingers. In the lower limbs
flaps is used as an upstream flap or a thinned flap to cover the lower limb
defects.
The surgeons at the Plastic Surgery – Oral department, the 108
Military Hospital, performed the first case using ALT flap in 1998. Since
then, there has been a growing number of research that facilities and
initially uses ALT flaps in clinical with widely applications, from the head
and neck, to the upper and lower extremities, etc Combining with
microsurgical techniques, skin expansion techniques, flap thinning
techniques, we now can significantly improve the vitality of this flap.
Chapter 2 - SUBJECTS AND METHODS
2.1. Design and subjects

This is a cross-sectional descriptive study. Subjects of the study were
formaldehyde-treated cadavers at the Anatomy department of Pham Ngoc
Thach University of Medicine since 1/2009 to 6/2011.
2.2. Subject selection
- Sample size: 60 thighs of 30 cadavers selected.
* Sampling criteria
1. Cadavers of Vietnamese over 18 years old.
2. Having 3 years soaked in formaldehyde solution 10%.
3. Thigh region intact.
* Exclusion criteria
Congenital abnormalities or diseases (tumors, vascular tumors, ) or
surgery on the thigh (vessel connecting, vessel coupling, shunting, ) that
can change or distort anatomical vasculature structures from the FA, DFA,
or LCFA.
2.3. Research Methodology
2.3.1. The indicators to be collected
* The qualitative assessment: we conducted and recorded:
- Origin and division of LCFA.
- Pathway, and association with muscles, nerves, veins of LCFA and
its branches.
- Origin, pathway, association, number of perforators from the
ascending, horizontal and descending branches of LCFA.
- Type of perforator, direction, angle to the skin, layered diameter,
location of perforator from branches of LCFA in relation with the circle of
3cm, 4cm, 5cm, 6cm radius, respectively.
* The quantitative assessment: (measured in millimeters - mm)
- Length of the femoral baseline.
- Outer diameter at origin of the LCFA.
- Distance from the origin of DFA to the origin of LCFA.
- Outer diameter at the origin of the ascending branch, horizontal

branch, descending branch of the LCFA.
- Diameter at the origin, diameter at the skin, length of the perforator
from the ascending, horizontal and descending branches of the LCFA.
- The angle to the skin of perforators from branches of the LCFA.
2.3.2. Dissection and data collection methods
Revealing septal and muscular structures of the anterolateral thigh,
FA, DFA, LCFA and its branches and perforators. Observing and recording
assessments. On each thigh, mapping the entire branches of LCFA to have
an overview of identifying the branches of LCFA.
2.3.3. The principles for determining branches of LCFA.
We propose these principles for determining those branched of LCFA
to facilitate the description and statistical measurement of those branches,
to serve the research and further academic surgical research. Our principles
are based on the following factors:
(1) The presence of the main trunk and its branches: ascending,
horizontal and descending branches.
(2) The relationship among branches of LCFA.
(3) The origins of the branches of LCFA.
- The naming principles:
Determining the descending branch
Take the descending branch’s origin as a landmark
Descending branch from the LCFA trunk
Descending branch from the FA
Descending branch from the DFA
Note the origin as order:
- from medial to lateral
- from above to below
Figure 2.1. The order to identify in case of multiple descending
branches.
- The rules of determining branches:

Group
Correlation b/w ascending and descending branches
Correlation b/w horizontal branch and ascending/ descending branches
Origin of LCFA or ascending branch if there’s no LCFA
Origin of descending branches which don’t derived from LCFA (if avaiable)
Chart 2.2. Rules to define the branches.
This classification is relatively complex, but it is necessary for in-
depth anatomical research, for clinical applications there should be an
integration into simpler and easier to remember groups.
Chapter 3 – RESULTS
3.1. Sample characteristics
We dissected 60 thighs of 30 cadavers, including 13 women (43.3%),
17 men (56.7%) and noted some common characteristics of the sample are
as follows: the average age of sample was 56.2 ± 17.8 years, femoral
baseline’s length was 415.3 ± 26.9 mm.
3.2. Anatomical characteristic of the lateral circumflex femoral artery
3.2.1. Origins & bifurcations of the lateral circumflex femoral
artery
LCFA majorly separated from the lateral aspect of DFA (85%), or
from the FA (13.3%) or from the back of DFA (1.7%), 21.1 ± 15.1mm
from the origin of DFA, its diameter was 4.1 ± 0.9mm.
According to our principles, we noted there were 13 types of LCFA
branching, in which type 1 (IC2 / S) accounted for the highest percentage
of 45%, the presence of the main trunk of LCFA was also high 71.7%.
These 13 types could be gathered into five groups as follows:
- Group I (53.3%): 1 descending branch, the branches have 1 common
trunk originated from the DFA. (types 1 and 2).
- Group II (1.7%): 1 descending branch, the branches have 1 common
trunk originated from the FA (type 3).
- Group III (15%): 1 descending branch, there are 2 separate branches

derived from the DFA (type 4,5,6).
- Group IV (6.7%): 1 descending branch, 1 branch separated itself
from the FA, 1 branch separated from the DFA (type 7, 8).
- Group V (23.3%): 2 descending branches (type 9, 10, 11, 12, 13).
3.2.2. Anatomical characteristics of the ascending branch of LCFA
This branch often split from the LDFA (76.7%), or from the DFA
(21.7%), rarely isolated from the FA (1.7%). Ascending branch can give
off the horizontal branch (81.7%) or without any branching (18.3%). Its
average diameter was 2.6 ± 0.6 mm, length was 95.9 ± 2.7 mm, and then
gave off about 4.1 branch to support the lateral thigh area, 2.8 average for
percutaneous circuit.
3.2.3. Anatomical characteristics of the horizontal branch of
LCFA.
Horizontal branch was only found in 6 specimens (10%). Due to the
low numbers, not sufficient for our survey, we only describe some
characteristics.
3.2.4. Anatomical characteristics of the descending branch of
LCFA.
Most of studied subjects had one descending branch (78.4%),
separated from LCFA (55%), or from DFA (16.7%), or separated directly
from FA (5%). When there were two descending branches (21.6%), they
could both be separated from LCFA (16.7%), or separated differently from
LCFA, DFA or FA. The outer descending branch had an average diameter
of 2.9 ± 0.8mm and an average length of 262.7 ± 4.3mm; the inner
descending branch had an average diameter of 2.5 ± 0.7mm and an
average length of 196.9 ± 17,5mm. Descending branch gave off 9.8 ± 4.7
branches for muscles, 22 ± 0.2 for the rectus femoral muscle, 7.9 ± 0.4 for
the vastus lateralis muscle, and 3.7 ± 0.3 perforators.
3.3. Anatomical characteristics of the perforators from branches of
LCFA

3.3.1. Characteristics of the perforators from the ascending and
descending branches of LCFA
3.3.1.1. Perforators from the ascending branch
The ascending branch gave off 176 perforators (43.5%). Outer
diameter of these perforators at origins were 0.98 ± 0.5mm, at skin levels
were 0.91 ± 0.5mm, length 27.1 ± 15.7mm. Those perforators often ran
downward (53.4%) and outward to the femoral baseline (79.5%). 43.8% of
the perforators went oblique to the surface of the skin, or nearly parallel to
the surface of the skin (31.8%), vessels ran perpendicular to the surface of
the skin were lower (24.4%). Perforators type M were dominant (88.1%),
the majority of them had diameter greater than 0.5 mm at the skin level
(79%). Perforators of the ascending branch were located mostly at the
portion 2 and the first haft of the portion 3 of the femoral baseline, and
laterally of this line.
3.3.1.2. Perforators from the descending branch
The descending branch gave off 226 perforators (55.8%). Outer
diameter of these perforators at origins were 1.1 ± 0.6mm, at the skin level
were 1.0 ± 0.5mm, length 29.6 ± 17.1mm. Those perforators often ran
downward or toward the front (68.1%), they might be focused outside or
inside the femoral baseline (67%). 74.8% of those perforators ran parallel
or oblique to the skin surface, they might also run perpendicular to the skin
surface (25.2%). Perforators type M were dominant (81%). Perforators of
the descending branch were located mostly at the portion 5 and 6.
3.3.2. General characteristics of the perforators originated from
the LCFA
More than 98% of perforators were originated from the descending or
ascending branch of LCFA. Perforators type M were dominant 340/405
(84%), perforator type S (8.9%) and perforators type D (7.1%) were
accounted for the lower rate. Those perforators frequently ran parallel or
oblique to the skin surface.

Table 3.10. Direction of perforators to the skin.
Direction
type
M
(n =
340)
type S
(n =
36)
type
D
(n =
29)
Vertical Upward 22,6% 19,4% 6,9
axis
%
Toward
the front
35,6% 41,7%
27,6
%
Downward 41,8% 38,9%
65,5
%
Sum 100% 100%
100
%
χ
2
0,102

Horizonta
l axis
Outer 54,7% 22,2%
58,6
%
On the
baseline
17,4% 52,8%
17,2
%
Inner 27,9% 25%
24,1
%
Sum 100 100%
100
%
χ
2
0,061
3.3.3. The distribution on the surface of the skin of the perforators
from branches of LCFA
3.3.3.1. Distribution on the femoral baseline
If we divided the baseline into three parts, perforators often appeared
in the first two-third portions close to ASIS (83.7%). Perforators type M
highly concentrated in the first third and two thirds portions, while
perforators type S concentration in the two thirds portion. If we divided the
baseline into ten parts, perforators were focused from the 2/10 to 7/10
portions (83%). Perforators type S and D majorly appeared in 4-6 / 10
portions (12.3%), the rest is distributions of perforators type M. When we
split the baseline into 16 equal parts, perforators were distributed mainly in

[3/16 - 5/16] and [10/16 - 12/16] portions (33.8% and 26.2% respectively).
Perforators type M concentrated in the range above, perforators type S and
D focused in [6-9 / 16] portions, which is about focusing circuit at regular
intervals of M than the other. Circuit across the majority of the skin around
the thighs and the concentration to 72.6% in [2/8 - View 6/8].
Chart 3.6. Distribution of perforators originated from branches of
LCFA, classified by type of perforator when dividing the baseline into
8 portions.
3.3.2.2. Distribution center of the perforators from LCFA.
Table 3:12. Distribution of type of perforators within the circle with
center is the midpoint of the baseline.
Radius Type M Type S Type D Sum
30mm 34
(8,4%)
15
(3,7%)
3 (0,7%) 52
(12,8%)
40mm 53
(13,1%)
21
(5,2%)
5 (1,2%) 79
(19,5%)
50mm 75
(18,5%)
27
(6,7%)
8 (2%) 110
(27,2%)

60mm 90
(22,2%)
31
(7,7%)
9 (2,2%) 130
(32,1%)
When increasing the radius of the circle, the number of perforators
regularly appeared in this circle also gradually increased, predominantly
perforators from the descending branch, concentrated in 4 and 5 portions
on the baseline.
Chart 3:10. Distribution of 405 perforators (type of perforator) & 5cm
radius circle.
Chapter 4 - DISCUSSION
4.1. Sample characteristics
With the size of 60 thighs, this sample was not large but enough to
warrant statistical examinations. Results of thigh baseline’s length was
similar to the study on 50 samples of Z. Chen (416mm) but smaller than
the result of Malhotra (534.1 mm), the difference might be due to
differences in the status of Asians compared with the Americas.
Differences in leg length can affect the determination of perforators.
Therefore, our results determined the location of the perforators of the
LCFA in associated with the portions of the baseline, not the thigh’s
length.
4.2. Anatomical characteristic of the lateral circumflex femoral artery
4.2.1. Origins and bifurcations of the LCFA
The LCFA mainly originated from the deep femoral artery (86.7%).
Our result was higher than those of Tansatit T. (56.7%), Japanese (78.6%),
Turks (77.3%). However, this result was consistent with the results of
studies on the Korean population (86.8%). Our distance from the origin of
DFA to LCFA (21mm) was similar to J. Perera (2.362 cm), Dixit D.P. (23 -

44mm), and Prakash (2.5 cm).
Table 4.1. Compare the types of authorized lateral circumflex femoral
artery among authors.
Origin From FA From DFA
Tansatit 43,3% 56,7%
Uzel 19,1% 77,3%
Prakash 18,75% 81,25%
Fukuda 21,4% 78,6%
Dixit 16,7% 83,3%
Perera 14,6% 85,4%
Choi 13,2% 86,8%
Chúng tôi 13,3% 86,7%
Our outer diameter of the LCFA was slightly smaller than the results
of Tansatit T. and M. Uzel, but this difference was not large and might be
due to differences in race, to confirm this we need another study on a
larger sample size, racial diversity and unity on how to measure diameter.
We described the types of LCFA as follows: (1) classical type
including a main trunk and three branches, ascending, horizontal,
descending (11.7%); (2) there is a common trunk between the ascending
and horizontal branches, the descending branch separates from the FA,
DFA or LCFA (83.3%); (3) there is a common trunk between the
horizontal and descending branches, the ascending branch separates from
the FA, DFA or LCFA (5%). Besides changes in the composition of the
branches of LCFA, there exist an inner descending branch (23.4%), this
feature hasn’t been noticed by authors but this is considered an important
component of the connector system within the skin around the knee joint.
We noted 76.6% had one descending branch, in which the rate of
common trunk accounted for 55.0% (type I c2 / S) dominates (45%), 8.3%
of cases three branches all originated from the LCFA, like (c1 type I / S),
the rest divided among general body type from 4-8, two branches to

account for 23.4%, which is the rate of general body artery 21.7% with the
dominant type 9 (15%) , the rest 1.7% is no general body. If classified into
five groups, the group I and group V prevails and turns ratio is 53.5% and
23.3%. We should have discussed and agreed on how to define the naming
of unit of LCFA in the study of national and world, should be further
improved to be able to build a complete system called for the division of
the lateral circumflex femoral artery in particular and other arteries of the
system in general.
4.2.2. Anatomical characteristics of the ascending branch
When comparing between studies, we found that the most common
type of bifurcation in studies was the type of ascending branch arises from
the main trunk of LCFA (approximately 70%), this ratio is quite similar to
our results (76.7%). Number of muscular branches was rather similar to
the result of Kavita (4.26 branches / thigh), Choi S.W. (4.2 branch / thigh),
Kimata (2.31 branches / thigh), Tanvaa T. (2.2 branch / thigh). This
suggests that if after dissection, the ALF flap still could not find any
perforators, we should move higher toward the pelvic spines, we may have
a precious flap skin. Outer diameter of ascending branch was 2.6mm,
consistent with the results of Tansatit T. 2.4 mm and Choi S.W. 2.6mm, but
greater than the results of Nguyen Huy Phan 1.1 mm (0.8 to 1.5 mm), this
difference needs to be redefined in a study with larger sample sizes.
4.2.3. Anatomical characteristics of the horizontal branch
The horizontal branch of LCFA accounted for 10%, which is quite
similar to the results of Vuksanović, noting the presence of horizontal
branches was very low. Also, there is a note on how to identify the
horizontal branch, according to our principles, the horizontal branch must
comes from LCFA, DFA, FA, but when it separated from the ascending or
descending branches it is call horizontal sub-branches. This was the
reason why our ratio of the horizontal branch was so low. Our outer
diameter of this branch was 2mm, similar to the studies of T. Tansatit (2.9

mm) and accordance with the classic literature, horizontal branch has a
smaller diameter branch to the ascending and descending branches.
4.2.4. Anatomical characteristics of the descending branch
The descending branch of LCFA majorly originated from the LCFA
(approximately 80%), similar to the several domestic and foreign studies.
The outer diameter of the descending branch was 2.9mm, similar to the
results of T. Tansatit (3.4 mm), Choi S.W. (2.9 mm), Linh Diep Le (2.24
mm), and Tran Quoc Hoa (2.08 mm). However, the diameter of our inner
descending branches (2.5 mm) were slightly smaller than the result of
Tansatit T. The number of our perforators in the results of Tran Quoc Hoa
(3.65 perforators), slightly lower than the results of Tran Bao Khanh on
cadavers (4.64 perforators), however, our results were higher in his results
of patients (2.1 perforators) and also higher than the results of Linh Diep
Le (2.24 perforators); this is a need to examine on the larger sample size,
and combine with clinical assessments on patients to determine the number
of perforators.
4.3. Anatomical characteristics of the perforators of the LCFA
4.3.1. Characteristics of the perforators from the ascending and
descending branches of the LCFA
4.3.1.1. Perforators from the ascending branch
Classification of perforators’ diameters at their origins was mostly
greater than 0.5mm (79%), at the skin level was mostly greater than 0.5
mm (76.1%), this is a very favorable condition for vessel transplantations
of the flap, ensuring the ability to live well of the anterolateral thigh flap.
The length of perforators of Choi S.W. was 83.3mm, considerably larger
than ours (27.1mm), because the authors surveyed the entire length of
perforators from the original branches of LCFA. Our ratio of perforators
type M and D was similar to the results of Luo S.K., however, we noted
that the ascending branch gave off no perforators type S.
Perforators from the ascending branch often ran downward to the

patella (53.4%), which differed from classical literatures, this should be
studied further with a larger sample size to confirm. Angle to the skin of
perforators majorly concentrated in the angle smaller than 72
0
(75.6%),
this meant perforators from the ascending branch ran parallel or oblique to
the surface of the skin, this is a favorable condition for thinning the flap in
clinical application.
4.3.1.2. Perforators from the descending branch
Table 4.6. Compare types of perforators among authors.
Author (year) Size Type M (%) Type S (%) Type D (%)
WOLFF (1992) 100 90 10 (-)
LUO (1999) 10 75 20 5
CHOI (2007) 19 82,5 17,5 (-)
TANSATIT (2008) 30 76,9 23,1 (-)
L.D. LINH (2011) 87,36 12,64 (-)
T.B.KHÁNH (2009) 14 87,69 12,31 (-)
T.Q. HÒA (2009) 10 56,16 43,48 (-)
OUR RESEARCH (2012) 30 81 15,5 3,5
Although the sample sizes were different but the results shown the
superiority of the perforator type M and the percentage of the perforator
type S did not exceed 25%. Other authors have not reported the presence
of the perforator type D of Luo S.K., but our result of this type of
perforator was not much different from the authors. These characteristics
should be recognized and confirmed on a further research of larger sample
size.
The direction of the descending branch was mostly downward or
toward the front (68.1%), consistent with classical literatures; and it ran
parallel or oblique to the skin surface, consistent with the results of the
domestic authors.

The diameter of the descending branch was 1mm, most of the
perforators had the outer diameter at origin and at skin level greater than
0.5mm (76.5% and 74.8% respectively). In comparison with the study of
160 perforators in 38 thighs of Choi S.W., Korean, our results had no
significant difference in diameter, but it looked slightly larger in proportion
of perforators which had diameter greater than 0.5mm. But when
compared with Linh Diep Le (2.24mm) and Tran Quoc Hoa (2.08mm), our
results were a little lower, this could be interpreted as the authors surveyed
patients, where the blood vessels had larger diameters than in cadavers. In
comparison with Yu P., our diameter of perforators from the descending
branch was slightly larger, this should be reconfirmed in another study
with a larger sample size. However, this was also a positive remarkable
feature, showing high potential applications of the anterolateral thigh flap
on Vietnamese populations.
4.3.2. General characteristics of the perforators from branches of
LCFA
The descending branch gave off 183 perforators (53.8%), the
ascending branch gave off 155 perforators (45.6%) of the total number of
type M perforator; the descending branch gave off 35 perforators (97.3%)
and the ascending branch gave off 1 perforator (2.7%) of the toral number
of type S perforators. Thus, perforators of the anterolateral thigh were
majorly type M, derived from the descending branch of LCFA, those
perforators ran parallel or oblique to the surface of the skin. Our result was
similar to Shieh S.J., however, the author noted that horizontal perforators
were derived from the descending branch and vertical perforators were
derived from the horizontal branch, but we only recorded that the
horizontal branch gave off a few perforators and they often ran downward.
This issue should be studied in a further study of larger sample size to
confirm.
Table 4.8. Compare the rate of perforators among authors.

Author (year)
Siz
e
Type M
(%)
Type S
(%)
WOLFF (1992) 100 90 10
LUO (1999) 10 75 20
CHOI (2007) 19 82,5 17,5
TANSATIT
(2008)
30 76,9 23,1
T.B. KHANH
(2009)
14 87,69 12,31
OUR
RESEARCH
(2012)
30 82,5 8,9
Although the sample sizes were different but all the results shown the
superiority of perforators type M. Thus, the ratio of type M: type S was
quite similar to foreign and domestic authors, at about 8:1. This might be a
common rate for perforators from other branches of LCFA.
4.3.3. The distribution on the surface of the skin of perforators
from the branches of LCFA
We noted that perforators mainly appeared in the portion of [3/16 -
5/16] and [10/16 - 12/16], particularly perforators type M, perforators type
S and D often located in the portion of [6/16 - 9/16], which was the less
focused area of perforators type M than the other portions. Tran Bao

Khanh also divided the femoral baseline into 16 portions and noticed
perforators concentrated in two portions [8/16 - 9/16] and [12/16 - 13/16],
this result is slightly different from ours, but they could both lead to a
general conclusion that perforators from the branches of LCFA
concentrated mainly in the lower half of the thigh, close to the patella.
However, the division of the femoral baseline into 16 portions might
clinically be somewhat too detailed and complicated, we suggested to
divide this line into 8 portions, then the perforators appeared up to 72.6%
in the portions of [2/8 - 6/8] and there was also no significant difference in
the number of perforators in those portions. This result did not differ much
from Choi S.W. but differed from Yu P. because our perforators did not
appear in the middle part of thigh but almost all of portions. Furthermore,
we also found that perforators had a very high concentrations in the
portion of [2/8 - 3/8], the blood supplied area of the ascending branch, this
would be clinically advantageous to expand the flap or when not found
perforators from the descending branch we should look in those two
portion for the probability of finding more perforators.
We recorded 83.3% had at least one perforator in the circle of 3cm
radius, and only 12.8% perforators (52/405 perforators) in this circle, most
of them were of type M (8.4%), type S (3.7%), and the lowest proportion
were of type D. When gradually expand the radius of this circle, we
recorded 96.7% of cases had at least one perforator in the circle of 4cm
radius, and 100% of cases had at least one perforator in the circle of 5cm
radius. When looking at the circle with a radius of 6cm, the proportion of
perforators in the circle were 32.1% (130/405 perforators). Thus, the
number of cases with at least one perforator in circles of our study was
equivalent to the results of other authors in the world, the probability of
finding a perforator in this circle was quite high, this was a hint to the find
and dissect the perforators of the anterolateral thigh flap. The circle of 5cm
radius was the minimum radius circle for the highest probability of finding

at least one perforator.
However, the number of perforators presented in those circles was
very low compared to the total number of perforators from the LCFA, this
was consistent with the results when divided the femoral baseline into 8
portions mentioned above, the perforators were not located in the middle
of the thigh but spread along the thigh in the portions of [2/8 - 6/8] and
there was not much difference in the number of perforators in those
portions, especially concentrated in the portions of 2/8 and 3/8.
CONCLUSION
1. We found that most of LCFA separated from deep femoral artery
and distal from its origin approximately 2cm, with an outer diameter of
about 4mm. We noted there were 13 types of branching of the LCFA,
classified into 5 main groups in which type Ic2/S had the highest rate
(45%). Separated mostly from the LCFA, the ascending branch had an
average diameter of 2.6mm. The proportion of perforators from the
ascending branch was 43.5%, in which there was no perforators type S.
The horizontal branch presented in a very low rate (10%), with an average
outer diameter of 2.0mm. the descending branch always presented, 76.6%
of the sample had one descending branch. Outer diameter of the
descending branch (or lateral descending branch) was at an average of
2.9mm, diameter of the medial branch was 2.5mm. The proportion of
perforators from the descending branch was accounted for 55.8%, which
was dominant by the perforators type M (81%).
2. About the anatomical characteristics of the perforators from the
LCFA, most of them were perforators type M derived from the descending
branch, and often ran parallel or oblique to the surface of the skin. There
were significant statistic differences between the sizes and the types of
perforators, this indicated that the length of the flap depends on the type of
perforators in that location. With the femoral baseline divided into 8
portions, the perforators concentrated up to 72.6% in the portions from 2/8

to 6/8. Since then we suggested a location to find perforators from LCFA
when within the circle of 3cm radius (center point is the midpoint of
baseline) we could not find any perforators, then we could find other
perforators in the circle of 5cm radius with the center was the 2/8 or 6/8
point on the baseline.