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 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 28  |  Issue : 1  |  Page : 74-79

Free anterolateral thigh flap in head and neck reconstruction


1 Department of General Surgery, Menoufia University Hospital, Menoufia, Egypt
2 Department of Plastic and Reconstructive Surgery, Menoufia University Hospital, Menoufia, Egypt

Date of Submission07-May-2014
Date of Acceptance07-Jun-2014
Date of Web Publication29-Apr-2015

Correspondence Address:
Mohammed Abdullah El-Nahas
Shebin Elkoom, Menoufia
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-2098.155947

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  Abstract 

Objectives
The aim of this randomized prospective trial was to evaluate indications, advantages, disadvantages, and complications of the usage of anterolateral thigh (ALT) flap as a free flap in head and neck reconstruction.
Background
Reconstruction of the head and neck continues to pose a formidable challenge for maxillofacial and plastic surgeons.The free ALT flap has emerged as a popular option for the reconstruction of head and neck defects. The present study evaluates the usage of free ALT flap in head and neck reconstruction.
Materials and methods
From January 2012 to January 2013, patients who had extensive soft-tissue defect in the head and neck and had been reconstructed by free ALT flap have been reported. Flap data (type, length, and width), duration of flap elevation, donor-site morbidity, postoperative complications, and follow-up data including aesthetic and functional outcome were recorded.
Results
The mean total harvest time of the flap was 113 min, the mean skin paddle width in our study was 10 cm (range, 7-15 cm), and length was 13 cm (range, 10-16 cm). The donor site in all cases had been closed directly. Failure of microvascular anastomosis occurred in one flap (from a total of three cases in the study), although no significant donor morbidity has been reported.
Conclusion
The ALT flap can be reliably harvested without incurring serious donor morbidity. It possesses workhorse attributes (no repositioning, remote from defect, and long pedicle) and is extremely versatile, making it ideal for the heterogeneous group of extensive soft-tissue head and neck defects.

Keywords: Anterolateral, flaps, microsurgery, thigh


How to cite this article:
Gad SS, Ghareeb FM, Elsheikh YM, El-Nahas MA. Free anterolateral thigh flap in head and neck reconstruction. Menoufia Med J 2015;28:74-9

How to cite this URL:
Gad SS, Ghareeb FM, Elsheikh YM, El-Nahas MA. Free anterolateral thigh flap in head and neck reconstruction. Menoufia Med J [serial online] 2015 [cited 2024 Mar 29];28:74-9. Available from: http://www.mmj.eg.net/text.asp?2015/28/1/74/155947


  Introduction Top


The goal of reconstruction in the head and neck involves three fundamental components: wound healing, function, and cosmesis. When deciding which reconstructive option is best suited for a particular patient, the reconstructive ladder must be taken into consideration [1].

The free anterolateral thigh (ALT) flap has emerged as a popular option for the reconstruction of head and neck defects. It has the attributes of a 'workhorse' flap that include the absence of patient repositioning, remote location from the potential defect, and a long pedicle [2].

The ALT was first described by Song in 1984. It should be emphasized that the skin associated with this flap is ALT skin, and that the pedicle is the descending branch of the lateral circumflex femoral artery. This differs from the lateral thigh flap that was described by Baek in 1983 that involves the posterolateral thigh skin and a pedicle from the third cutaneous perforator of the profunda femoris artery [3].

The main indication of using free ALT flap is the five major types of extensive soft-tissue head and neck defects:

  1. Subtotal or total glossectomy defects;
  2. Extensive skull base defects [4];
  3. 'Through-and-through' buccal defects;
  4. Extensive scalp defects [5]; and
  5. Extensive orbitomaxillofacial defects. With respect to the orbit, the ALT provides sufficient soft tissue and skin to fill the dead space within an exenteration cavity, and to cover any implants or plates required for adjacent midface reconstruction [6].


The unique anatomy of the thigh permits several methods of harvesting the ALT flap. The type of tissues to be included in the flap can be selected according to the defect to be reconstructed. The ALT flap can be harvested at the suprafascial level to include just the skin and subcutaneous fat, which is useful when a thin flap is desired [7]. When harvested at the subfascial level, the flap can bring additional tissue bulk including the fascia lata on the deep surface. The fascia is particularly useful in several situations, such as when repairing dural or tendon defects and when creating a sling to support the oral commissure [8]. A musculocutaneous flap can be harvested by including a part of the vastuslateralis muscle [7]. The muscle can be attached to the overlying skin or splayed out on a separate vascular branch that arises from the same vascular pedicle to create a chimeric flap [8].

The ALT flap possesses many of the important properties that make a flap ideal for head and neck reconstruction, namely:

  1. Anatomically constant with a long and sizeable pedicle;
  2. Good match for recipient-site tissue characteristics;
  3. Flexibility of tissue volume, be it thick, bulky, or thin and pliable;
  4. Flexibility in design, including the availability of different tissue types for harvesting on the same pedicle, as in a chimeric flap;
  5. The option to harvest two separate flaps from the same site;
  6. Insignificant donor-site morbidity;
  7. Simultaneous flap harvest and tumor ablation afforded by a two-team approach; and
  8. The option for sensory reinnervation [9].


Keeping these facts in mind, ALTs have recently taken an increased role in head and neck reconstruction [10].

Thus, the aim of the study was to evaluate indications, advantages, disadvantages, and complications of the usage of free ALT flap in head and neck reconstruction.


  Materials and methods Top


This is a prospective study, which was carried out in the Plastic Surgery Department, Menoufia University Hospitals, from January 2012 to January 2013. It includes all patients who had extensive soft-tissue defect in the head and neck and had been reconstructed by free ALT flap. The patients included were those with extensive soft-tissue head and neck defects, which could not be closed by local flaps, and were fit for surgery. The patients excluded were those with small defect, which could be closed by local flaps, and were not fit for surgery (old age, cardiac, diabetic, etc.). The study included three patients (all female) ranging in age from 41 to 55 years old. Informed consent was obtained from all patients included in the study that was approved by the local ethics committee. All the patients were subjected to preoperative history taking, clinical examination, laboratory investigations, and radiological examination.

Preoperative management

Preoperative evaluation of the perforators was performed using a Doppler probe by auscultating the skin in the region of the lateral intermuscular septum and over the medial parts of the vastuslateralis muscle.

Surgical procedures

Anesthesia

General anesthesia was administered with endotracheal intubation.

Patient positioning

The patient is placed in the supine position, and the whole leg is included in the operating field to allow for free positioning of the extremity and for modifying the flap design, if necessary.

Flap design

The standard skin paddle of the flap may be extended from the medial border of the rectus femoris to the lateral border of the vastuslateralis muscle, covering the middle third of the thigh. The center of the flap depends on the individual location of the perforator(s), which can be found a few centimeters proximal to the midpoint of the interconnection between the anterior superior iliac spine and the patella in most patients. Because of the variability of the perforators, the skin paddle is not circumcised until the perforator is identified from the medial border of the flap. The skin marking is started by a line drawn from the anterior superior iliac spine to the superolateral border of the patella that corresponds to the intermuscular septum. A second line is drawn from the midpoint of the initial vertical line to the midpoint between the anterior superior iliac spine and the symphysis pubis. This second line corresponds to the descending branch of the lateral circumflex femoral artery [Figure 1]a. The skin paddle is placed with its long axis over the septum between the rectus femoris and vastuslateralis muscles. The anterior third of the flap is positioned anterior to the initial line, and the remaining two-third of the flap are placed posterior to the line.
Figure 1: Steps of flap raising.

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Flap raising

First, the anterior skin incision is made, and then a stair-step incision is made through the fascia, 1 cm medial to the skin incision, to prevent damage to obliquely oriented perforators [Figure 1]b. The intermuscular septum between the vastuslateralis and rectus femoris muscles is first identified distally, where it is more easily identifiable. The septum is then opened from distal to proximal, and the vastuslateralis is separated from the rectus femoris. Once the rectus femoris muscle is dissected and swept medially from the vastuslateralis muscle, the descending branch and its perforators are easily identified. There is often a short oblique branch or proximal perforator that inserts at the terminal insertion of the tensor fasciae lata muscle. This perforator or oblique branch is our first choice in every case, because of its short dissection and superficial location, which is very often subcutaneous [Figure 1]c.

After the descending branch of the lateral circumflex femoral artery is identified, perforator selection is undertaken. Two choices are possible. If there is a proximal perforator, which corresponds to either the oblique branch of the lateral circumflex femoral artery or to a proximal perforator, this perforator is selected [Figure 1]d.

The reasons for this are that the perforator can be dissected simply and quickly, given its superficial course, which is either subcutaneous or just under the vastuslateralis muscle. If this branch is not available, the rest of the perforators running through the vastuslateralis muscle are identified and selected. If no perforators are suitable, the anteromedial thigh territory is explored to look for perforators overlying the rectus femoris or sartorius muscles. We perform perforator dissection with a combination of monopolar and bipolar cautery. The perforator and the descending branch of the lateral circumflex femoral artery are dissected up to the level of the rectus femoris branch, as required.

Although the myocutaneous perforators travel through the muscle for only a few centimeters, a large segment of the vastus muscle is integrated in the flap to safely include all the perforating branches. Starting distally, the muscle is dissected in the plane above the vastus intermedius fascia until the anterior rim of the vastuslateralis is nearly reached. Additional muscle branches will be transected during dissection of the muscle segment, which then have to be cauterized or clipped.

The size of the paddle is determined according to the size of the defect to be reconstructed. The posterior incision is then made. A small skin paddle attachment bridge is kept intact superiorly to minimize any risks of shearing of the pedicle. This small bridge of skin is then incised once the pedicle is transected and ready for transfer. The microvascular anastomosis is performed on the facial vessels, internal jugular vein, and superior thyroid vein in the standard manner, and the flap is inset in place without tension. A penrose drain is inserted under the flap to prevent accumulation of hematoma.

Postoperative close monitoring of the vital data of patients, especially arterial blood pressure for optimal tissue perfusion, was carried out with close surveillance for hematoma formation to avoid vascular compression.

The collected results were analyzed and compared taking the following in consideration.

  1. Age and sex distribution.
  2. Flap data that include the duration of flap elevation, length, width and type of the flap, type of the perforator, method of closure of the defect, and recipient vessels.
  3. Postoperative complications data in the donor and recipient site that include wound infection, dog ear formation, total flap necrosis, hemorrhage, local abscess, and bulkiness of the flap.
  4. Follow-up data from the donor and recipient site that include the following.

    1. Donor site is divided into functional outcome and aesthetic outcome. Functional issues include gait alteration, sensory disturbance, and cold intolerance. Aesthetic issues include hypertrophic scarring, hypopigmentation/hyperpigmentation, keloid formation, and contour defect.
    2. Recipient site is divided into functional outcomes and aesthetic outcomes. From a functional perspective, problems encountered include speech problems, oral incompetence, swallowing problems, facial pain, nasal obstruction, and flap contracture. From an aesthetic perspective, problems encountered include flap sagging, color mismatch, hair growth, contour defect, and flap bulkiness.



  Results Top


The study includes three patients (all women), ranging in age from 41 to 55 years, who had extensive soft-tissue defect in the head and neck after malignant tumor excision and had been reconstructed by free ALT flap [Table 1].
Table 1 Patients' data

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The flap perforator was a musculocutaneous perforator and originated from the descending branch of lateral circumflex femoral artery in all cases. The length of the pedicle ranged from 10 to 15 cm. In all the cases, the pedicle was composed of one artery and two veins. The flaps ranged in size from 10 to 16 cm in length, and from 7 to 15 cm in width. The donor site was closed primarily in the three cases. Two flaps survived completely, and one suffered from complete necrosis owing to failure of microvascular anastomosis and was managed by replacement of the flap by pedicled pectorals major flap. Flaps' data are shown in [Table 2].
Table 2 Flaps' data

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The duration of postoperative hospital stay ranged from 12 to 14 days. There was no postoperative wound infection or dog ear formation in the donor site. According to the recipient site, the flap was bulky in one case, and no postoperative hemorrhage or local abscess was recorded. Postoperative complications data are shown in [Table 3], and follow-up data are shown in [Table 4].
Table 3: Postoperative complications data

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Table 4: Follow-up data

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Case report included a 41-year-old female patient with tongue squamous cell carcinoma [Figure 2]a. Two teams worked on the case. The first team worked on flap harvesting, in which preoperative ALT flap marking was carried out [Figure 2]b, and flap raising until the flap became ready for separation [Figure 2]c. After the second team finished tumor excision, separation of the flap was carried out [Figure 2]d. Intraoral defect was reconstructed by free ALT flap on the facial artery and two veins: in one vein, end-to-side anastomosis was performed with the internal jugular vein, and in the other end-to-end anastomosis was performed with the superior thyroid vein [Figure 2]e. Postoperative images of the donor and recipient sites are shown in [Figure 2]f and g.
Figure 2: Preoperative and postoperative photographs of case report.

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  Discussion Top


The role of microvascular reconstructive surgery in the head and neck is now firmly established. Concerns the reliability that dissipated through the 1970s, the freedom to select the best tissue match from almost anywhere on the body led a trend toward defect specialization. This trend produced a wide variety of free flaps for head and neck reconstruction, first reported in the 1980s. On the contrary, as the benefits of certain 'workhorse attributes' of these flaps (no repositioning, remote from defect, long pedicle) were recognized through the1990s, a trend toward flap specialization evolved [11].

To date, however, no single flap has arisen as the flap of choice for the more heterogeneous group of extensive soft-tissue head and neck defects. The ALT flap is an extremely versatile extremity flap as its moderately thick skin and large potential muscle bulk can be independently tailored to provide ideal tissue matches for this heterogeneous group of defects. It also possesses the workhorse attributes [12].

Song et al. in 1984, was the first to describe the ALT flap as a fasciocutaneous flap. The detailed anatomy of this flap was further presented from cadaver dissection or clinical experience, and it was found that the blood supply of the ALT flap was based on the septocutaneous or musculocutaneous perforators, or both [13].

Wolff and Grundmann [14] found that 90% of the flaps had musculocutaneous perforators, and 10% of the flaps had septocutaneous perforators. Shimizu et al. [15] described 41 cadaver studies. Of them, the cutaneous blood supply musculocutaneous perforators was found in 51%, and septocutaneous perforators in 49%. Kimata et al. [16] reported that the septocutaneous perforators were evident in 26.3% and musculocutaneous perforators in 73.7% of the 38 clinical cases. Shieh et al. [17] found that the perforator was a musculocutaneous one in 83.8% of cases, and a septocutaneous one in 16.2% of cases of the 37 clinical cases. Another study from Egypt reported the perforator was a musculocutaneous perforator in 13 (81.25%) cases, and septocutaneous perforator in three cases (18.75%) [18]. In our study, the perforator was a musculocutaneous perforator in all three cases. Transmuscular dissection through the vastuslateralis muscle was performed around the musculocutaneous perforator in one case, whereas in the other two cases cuff of the vastuslateralis muscle around the perforators was elevated without dissection.

Yildirim et al. [19] found that the perforator origin was from the descending branch of lateral circumflex femoral artery in 92.9%, and from the transverse branch in 7.1% of 28 clinical cases. Another study on 16 cases reported that the perforator originated from the descending branch in 15 cases (93.75%), and from the transverse branch of lateral circumflex femoral in one case (6.25%). If this anatomic variation is known by the surgeon, we believe that flap elevation should possess no difficulty. One should first find the perforator and then follow it in a retrograde manner [18]. In our study, we found that the perforator origin was from the descending branch of lateral circumflex femoral artery in all our three cases.

Not only does the anterolateral flap provide a plenty of soft tissue for reconstruction, but it also provides a plethora of options for reconstruction. It can be thinned if a thin flap is required, can be used as a sensate or flow through flap if used as a sensate or flow through flap in extremities reconstruction, and if bulk is needed it can be harvested with a piece of the vastuslateralis [18]. In our study, one flap has been elevated as a fasciocutanous flap without any piece of the vastuslateralis muscle, and the other two flaps were elevated with a cuff of the vastuslateralis muscle around the perforators.

According to Lueg [12] the mean total harvest time of the flap was 50 min (range, 41-75 min). In our study, it was the longer period ranging from 60 to 210 min (mean 113 min). The mean skin paddle width in our study was 10 cm (range, 7-15 cm), and length was 13 cm (range, 10-16 cm).

A particularly important advantage of the ALT flap is the relatively low donor site morbidity that accompanies even a substantial flap harvest. The donor site can be closed primarily if the width of the flap does not exceed about 8 cm, but wider flaps needing a split-thickness skin graft for closure of the donor site [20]. In our study, the donor site of all cases was closed directly.

The recipient vessels for microvascular anastomosis were end-to-end anastomosis to facial artery and vein in one case of tongue squamous cell carcinoma, whereas in the other case of tongue squamous cell carcinoma the microvascular anastomosis was done by end-to-end technique to facial artery and end-to-side technique to internal jugular vein in one vein and another end-to-end anastomosis with superior thyroid vein, about the case of check squamous cell carcinoma the microvascular anastomosis was done by end-to-end technique to external carotid artery and external jugular vein.

Postoperative complications data were divided into donor-site complications and recipient-site complications.

The donor-site complications include neither wound infection nor dog ear formation in any case.

The recipient-site complications include failure of anastomosis in one case, which was managed by replacement of the flap by pedicled pectorals major flap. The flap was bulky in that case, and no postoperative hemorrhage or local abscess was recorded. The duration of hospital stay ranged from 12 to 14 days (mean 13 days).

Dissection and protection of the nerve to the vastuslateralis muscle should be performed carefully to preserve maximal quadricep function when harvesting a cutaneous ALT flap. The inclusion of a segment of the vastuslateralis muscle might be expected to increase donor-site morbidity; however, it was objectively demonstrated at long-term follow-up with a kinetic communicator machine that only a minimal weakness of the thigh results [21]. Other studies show no significant functional deficits noted either by the patient or examining physician on the donor site [22]. In addition, in our study, no significant functional deficits were noted either by the patient or examining physician (no gait alteration, no sensory disturbance, and no cold intolerance) with regard to aesthetic deficits. There was only a scar line at the donor site without recording any hypopigmentation or hyperpigmentation, keloid formation, or contour defect at the donor site of the flap.


  Conclusion Top


The free ALT flap can be reliably harvested without incurring serious donor morbidity. It possesses workhorse attributes (no repositioning, remote from defect, and long pedicle) and is extremely versatile, making it ideal for the heterogeneous group of extensive soft-tissue head and neck defects.


  Acknowledgements Top


Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
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2.
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Posch NA, Mureau MA, Dumans AG, Hofer SO. Functional and aesthetic outcome and survival after double free flap reconstruction in advanced head and neck cancer patients. Plast Reconstr Surg 2007; 120 :124-129.  Back to cited text no. 3
    
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12.
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Kimata Y, Uchiyama K, Ebihara S. Versatility of the free anterolateral thigh flap for reconstruction of head and neck defects. Arch Otolaryngol Head Neck Surg 1997; 123 :1325.  Back to cited text no. 16
    
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Shieh SJ, Chiu HY, Yu JC. Utilizing free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation. In Proceedings of the 14th Congress of the International Microsurgical Society; 1998; Corfu, Greece.  Back to cited text no. 17
    
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19.
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21.
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    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]


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