Double subcutaneous island pedicle flap for reconstruction of large upper and central chin defects

Chin reconstruction poses a significant task for dermatologic surgeons due to its unique contour and shape, as well as the fact that it features the thickest skin on the face, resulting in typically poorer scarring in this area compared to other facial locations.1 There are numerous reconstructive options employed for the closure of oncological surgical defects in the chin region, ranging from advancement, transposition2 or rotation flaps to much more complex choices like free flaps.3 We present a case of a surgical defect in the midportion of the chin successfully reconstructed using a double island advancement flap. A healthy 71-year-old female presented with a recurrent basal cell carcinoma on her chin (Figure 1). Excision by micrographically controlled surgery was planned. A bilateral mental nerve block with local anesthetic was performed to achieve suitable anesthesia. After the complete excision of the tumor, a final 4.5 × 3.5 cm defect remained, involving full-thickness skin and the Musculus depressor labii inferioris, with partial exposure of the mandibular bone (Figure 2a). A double island flap was design by positioning the upper incision lines along the vermilion border of the lower lip and creating the lower incisions along the mental crease. The flaps were crafted in a subcutaneous plane, undermining the most medial and lateral portions, leaving a subcutaneous pedicle in the central area of both flaps to ensure vascular supply. The median margins of the flaps were sutured into place with interrupted subcutaneous sutures, and a V-Y suture was placed in their lateral portion. Polyglactin 4/0 and polypropylene 5-0 were the suture materials used to secure the flaps (Figure 2b–f). The postoperative period proceeded without complications, and the sutures were removed 7 days after surgery. The first report of a random-vascularized subcutaneous pedicle flap for cutaneous defects dates back to 1965 by Barron and Emmett.4 Since its initial description, a wide variety of modifications and applications to different skin areas have been described. The island pedicle flap has traditionally been designed as a V-Y advancement-type flap, although various authors have described modifications of this flap that allow for a transpositional movement, enabling the rotation of the pedicle and even tunnelization.5 It represents a highly versatile reconstructive option allowing us to address defects in various locations, such as the cheek, nose, or upper lip, with excellent outcomes.6 In fact, many authors consider these flaps as their first choice for closing defects located on the lateral portion of the upper lip or in the eyebrow region.7 However, the application of these island flaps is less frequently chosen for the closure of defects in the chin region, even though similar cases are described in the literature.8 The direct insertion of mimetic muscle fibers into the skin, along with its greater thickness, makes chin skin less distensible and less mobile compared to other locations. This factor likely contributes to the infrequent consideration of island flaps for defect closure in this anatomical area. However, it is important to consider that the skin in the mid-portion of the chin has greater laxity, particularly in the lateral regions of the mental crease, making them a potential donor area. Among the advantages of the double pedicle island flap, it is worth highlighting its high viability due to the blood supply primarily consisting of the mental artery, which should be preserved during dissection. Additionally, branches of the labiomental and submental arteries provide densely populated musculocutaneous perforators to the skin, ensuring the feasibility of the flaps. Moreover, it is essential that during the crafting of the flaps, dissection is conducted with utmost care to prevent potential injuries to the mental nerve bundle that may result in transient or even permanent loss of sensation in the lower lip. The cosmetic results of this reconstruction technique are particularly advantageous compared to other reconstructive methods. Both upper and lower horizontal incisions are placed at the cutaneous-vermilion junction and the mentolabial sulcus, allowing for excellent scar camouflage. We have also managed to transform some well-known disadvantages of island pedicle flaps into cosmetic benefits. The horizontal vector of advancement imparts the greatest tension to the vertical sutures in the midportion, which can lead to a depression in the center, recreating the concave surface of the labiomental fold. Lastly, the inferior traction of the vermilion when suturing the upper margin of the flaps results in an eversion of the lower lip. This circumstance translates to a noticeable aesthetic improvement (Figures 1, 3), particularly in older patients, as the fullness of the lip decreases with age, concomitant with the diminishment of the vermilion border lip roll. In conclusion, the double pedicle island flap represents an easy and elegant reconstructive alternative for central chin defects that allows us to preserve the contour and shape of this anatomical structure, which significantly contributes to the overall appearance of individuals. We thank the patient for her cooperation and consent to publish her clinical images. None.