Inclusion of the Perforating Branch of the Tenth Intercostal Artery in the Distal Skin Paddle of the Divided Latissimus Dorsi Flap

Abstract

Sir: We read with great interest the article on the divided latissimus dorsi flap by Zhang et al.,1 who reported the use of the latissimus dorsi flap with multiple separate skin paddles for the reconstruction of large defects and achievement of primary closure of the donor site. The largest surface area elevated was 280 and 340.5 cm2 for the bilobed and trilobed flaps, respectively. They described two cases of trilobed flaps, one of which was complicated by partial necrosis of a skin paddle. Sawaizumi and Maruyama2 described a sliding shape–designed latissimus dorsi flap in 1996. They divided an oval defect into two parts in the oblique long axis direction, and these two semicircular parts were traced onto the latissimus dorsi flap to lengthen it vertically. After the extended latissimus dorsi flap was elevated, it was divided into two semicircular flaps and united again to create an oval flap. This method enabled them to elevate an area up to 360 cm2 (20 × 18 cm) while avoiding partial necrosis and achieving primary closure of the donor site. However, they did not describe the detailed vascular anatomy of the flap. In an anatomical study by Watanabe et al.,3 a descending branch of the thoracodorsal artery running parallel to the lateral border of the latissimus dorsi muscle was connected directly to the perforating branches of the ninth and tenth intercostal arteries in the lateral part of the muscle by means of a true anastomosis. Furthermore, a horizontal branch running parallel to the superior border of the latissimus dorsi muscle was connected directly to the perforating branches of the ninth intercostal artery in the medial part of the muscle by means of a true anastomosis. These three perforators from the intercostal artery were included in the first vascular territory of the latissimus dorsi muscle. Furthermore, an anatomical study conducted by Minabe et al.4 demonstrated that the tenth perforator is dominant among the intercostal artery perforators. We consider the inclusion of the tenth perforator in the distal skin paddle of the divided latissimus dorsi flap to be important because it allows for extension of the skin paddle in the anterior, posterior, and distal directions, thereby overcoming the choke vessel in the subcutaneous tissue. Distally, the skin paddle can be safely extended up to the iliac crest. The partially necrosed trilobed flap presented by Zhang et al.1 may not have included an adequate perforator. Besides, the design of the flap and the shape of the donor-site scar were complicated. We included the tenth perforator in the distal skin paddle and used the sliding shape–designed flap to reconstruct a large defect, thus facilitating safe elevation and a sigmoid curvilinear donor-site scar (Fig. 1). Although elevation of multilobed skin paddles nourished by a pedicle of the thoracodorsal artery may be beneficial, the divided sliding shape–designed flap including the tenth perforator of the tenth intercostal artery in the distal skin paddle is preferable for elevating a large flap and achieving primary closure of the donor site. Fig. 1: A 60-year-old woman who underwent resection of a liposarcoma on the right shoulder. (Left) The location of the perforating branches of the tenth intercostal artery in the lateral part of the latissimus dorsi muscle was detected by color Doppler sonography. The divided latissimus dorsi flap was designed to include the perforator in the distal flap. (Right) Three months after primary closure of the donor site.DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. Shinsuke Akita, M.D., Ph.D. Department of Plastic and Reconstructive Surgery Chiba Cancer Center Nobuyuki Mitsukawa, M.D., Ph.D. Department of Plastic, Reconstructive, and Aesthetic Surgery Chiba University Faculty of Medicine Tatsuya Ishigaki, M.D. Department of Plastic and Reconstructive Surgery Chiba Cancer Center Shintaro Iwata, M.D., Ph.D. Tsukasa Yonemoto, M.D., Ph.D. Department of Orthopaedic Surgery Chiba Cancer Center Kaneshige Satoh, M.D., Ph.D. Department of Plastic, Reconstructive, and Aesthetic Surgery Chiba University Faculty of Medicine Chiba City, Japan