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 [...]... 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... 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) WOLFF (1992) LUO (1999) CHOI (2007) TANSATIT (2008) T.B KHANH (2009) OUR RESEARCH (2012) Siz Type M Type S e 100 10 19 (%) (%) 90 75 82,5 10 20 17,5 30 76,9 23,1 14 87,69 12,31 30 82,5 8,9 Although the sample sizes were different but all the results shown the... 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 . 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