**2.2 Flap harvesting**

*Marking* (**Figure 1**): Marking of the flap is preferred in a standing position. The midline of the back is marked which is the posterior border of LD. Then posterior axillary line, which runs from the posterior border of the axilla to the iliac crest

**Figure 1.** *Marking for LD myo-cutaneous flap.*

**Figure 2.** *Defect after mastectomy on left side.*

corresponds to the anterior border. A line joining from the midline touches the inferior angle of the scapula and joins the posterior axillary fold is the superior border. The Iliac crest is considered an inferior border of muscle [2].

Once all four borders are marked, the skin paddle is marked which can be drawn obliquely, or transverse according to defect size (**Figure 2**) and surgeon's preference with an aim of closure of donor area primarily and scar to be hidden maximally. Hammond recommends designing a skin paddle along the RSTL (relaxed skin tension line) [2]. The pedicle of LD, the thoracodorsal vessels is marked which is 2 cm behind and parallel to the anterior border of the muscle and 10–12 cm below the axillary fold.

*Positioning*: It is preferred to harvest LD myo-cutaneous flap in a lateral position with the arm abducted to 90 degrees, medially rotated, extended and supported on the other side by arm support. One should also never forget to put cotton or a pad over the bony prominence of the opposite shoulder and between knees to avoid any pressure necrosis due to prolonged operating time.

*Technique*: Once skin paddle and incisions are marked, it is begun with infiltration of tumescent solution or adrenaline with saline (1:2 lakh ratio) along the proposed incision to reduce bleeding. An incision is made over the margin of the marked skin paddle and LD muscle with a layer of fat over it is exposed from all sides. Fat provides a bit of bulk for breast reconstruction. However, for free flap or when it is used for another region, it is ideal to harvest the muscle only. Once the muscle is exposed, the anterior border of LD muscle is delineated and dissected which lies along the anterior axillary line. By doing a blunt dissection, a few centimeters behind the anterior border, the neurovascular pedicle of the LD muscle can be easily seen lying just below the muscle. Once the pedicle is seen, the muscle is dissected and cut from below at the thoracolumbar fascia. We can easily identify and define a thin layer of fat between LD and underlying intercostal muscles. If we stay in the fat layer, there is less chance of bleeding. Also, it is important to cauterize several perforators arising from the lumbar artery and intercostal artery to secure hemostasis.

Once the muscle is cut from its inferior and posterior border, it is dissected upward. At the inferior angle of the scapula, there is an intermingling of muscle fibers with teres major. The muscle is further dissected incorporating the vascular and neural pedicle and the flap is harvested (**Figure 3**). A tunnel is created from the defect through the axilla and muscle with a skin paddle is retrieved through the tunnel. During tunneling it is

**Figure 3.** *Neurovascular pedicle of LD flap.*

**Figure 4.** *Harvested LD myo-cutaneous flap attached with pedicle.*

always preferred to create a wide tunnel at least two to three fingers width wide to avoid compression of muscle and pedicle. If there is difficult reach, the muscle can be detached from its insertion and the flap is islanded over the pedicle (**Figure 4**). The flap is inset (**Figure 5**). A drain is always placed at the donor as well as the recipient site. To avoid hematoma, one can put several quilting sutures from under the skin to the back muscles. A compression dressing is provided in the form of dynaplast.
