Abdominis Free Flap


Fig. 6.1

Doppler identification of the vascular pedicle



6.3.2 Patient Positioning


Flap harvesting is performed with the patient in the supine position. The abdomen is exposed from the xiphoid to the pubis. The operative field should be prepared including the lower ribs and the upper thigh of both sides as well as the pubic area.


6.3.3 Flap Design


Design of the skin paddle can have different orientations: transversal (TRAM), vertical (VRAM), and oblique. In design planning, a part of the paraumbilical area should be always included, because most of the dominant perforators are herein located.


The VRAM flap includes only the skin above the rectus muscle of one side, while the TRAM flap may include also the contralateral skin. When planning the TRAM flap, it is useful to remember that the skin overlying the rectus abdominis muscles is divided into four zones: zone 1, portion above one muscle; zone 2, above the contralateral muscle; zone 3, lateral to zone 1; and zone 4, the less vascularized one and is positioned externally and lateral to zone 2 [3].


The TRAM variant is often used for mammary reconstructions but can also be used in the head and neck area.


In the variant with the oblique course (extended deep inferior epigastric flap), the skin paddle starts from the paraumbilical region and can reach up to the apex of the scapula, with the associated muscle taken as a whole or just in part. If necessary, this flap may also include a portion of the vascularized rib [4].


The main landmarks are the linea alba (blue arrow) outlined on the midline from the pubis to the xiphoid, the iliac crest (black arrow), and the costal margin (green arrows). The linea semilunaris is positioned about 7–10 cm lateral to the linea alba, between the pubis and the anterior superior iliac spine (yellow arrow).


The vascular pedicle (DIEA) is located at the inferolateral edge of the rectus abdominis muscle. The arcuate line is located approximately at the height of the anterior superior iliac spines. The anterior rectus sheath should not be harvested below this level (Fig. 6.2).

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Fig. 6.2

Preoperative identification of anatomical landmarks: linea alba (blue arrow), iliac crest (black arrow), costal margin (green arrows), linea semilunaris (yellow arrow)


VRAM is designed above a single rectus muscle. The central portion of the flap must be centered at the level of the periumbilical region and can be extended from the pubic region to the costal arch. Medial and lateral limits are represented by the linea alba and the linea semilunaris (Fig. 6.3).

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Fig. 6.3

VRAM: design of the flap


TRAM can be designed in the supra- or subumbilical regions. The amount of skin that can be safely harvested reaches 40 cm in length and 15 cm in width. Such big dimensions in the head and neck district are seldom necessary. However, this type of flap allows a substantial skin withdrawal and a reasonably esthetical closure of the donor site (Fig. 6.4).

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Fig. 6.4

TRAM: design of the flap


6.4 Surgical Steps


6.4.1 Step 1


Incision of the skin is performed along the entire edge of the skin paddle until it reaches the anterior rectus sheath (Fig. 6.5).

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Fig. 6.5

Step 1: TRAM skin incision


In the VRAM flap, the incision can be prolonged, along the paramedian line (black arrow) (Fig. 6.6).

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Fig. 6.6

Step 1: VRAM skin incision


Subsequently, the skin and subcutaneous tissue are dissected, exposing the anterior rectus sheath (Fig. 6.7).

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Fig. 6.7

Step 2: incision of anterior rectus sheath VRAM


6.4.2 Step 2


Incision of the anterior rectus sheath is carried out first cranially and then caudally until the muscle is exposed (Fig. 6.8), bearing in mind not to incise the rectus sheath below the arcuate line.

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Fig. 6.8

Step 2: incision of anterior rectus sheath TRAM


Upper and lower portions of the anterior sheath are incised. In VRAM flap, the vertical incision of the rectus fascia in a lateral position allows a direct suture facilitating the closure of the abdominal wall (Fig. 6.9). Every effort should be made to remove as less anterior rectus sheath as possible, undermining the subcutaneous plane, finding the perforators when they leave the fascia entering into the skin paddle, and removing just the small portion of fascia surrounding them. This sometimes allows removing a 3 × 3 cm piece of fascia, still vascularizing an 8 × 8 cm or more skin paddle.

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  4. Thigh Flap

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Apr 26, 2020 | Posted by in OTOLARYNGOLOGY | Comments Off on Abdominis Free Flap

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