When primary closure of facial defects is not an option, local and regional flaps are instrumental to re-establishing function and providing a highly cosmetic result. Local flaps have also been used in the treatment of secondary cleft lip and palate deformities, congenital orbitofacial deformities, velopharyngeal insufficiency, and in the posttraumatic or postablative treatment of children. A careful analysis of the defect characteristics and flap planning will optimize the reconstructive result and help restore psychosocial well-being in this population. Although an exhaustive review of all flaps is beyond the scope of this chapter, the authors will review the most commonly used local and regional flaps currently used in children.
56 Regional and Local Flaps in Children
The face plays a significant role in the recognition of the individual, social interaction, and critical functions such as communication, smell, sight, taste, respiration, and nutrition intake. Special consideration to social and emotional development must be given in pediatrics. At around 5 years of age, children begin to develop self-esteem and a sense of self-image. 1 Consequently, defects of the face may result in devastating emotional and psychological disturbances in this sensitive population. 2 Although children may exhibit a more vigorous healing response and fewer complications of chronic disease such as those in smoking and diabetes mellitus, treatment of maxillofacial defects in this population presents challenges not otherwise encountered in the adult population. This is partly credited to the unique anatomic and physiological variations in the growing facial skeleton. 3 Common etiologies of head-and-neck defects in the pediatric population include maxillofacial trauma, neoplasm (benign or malignant), infection, inflammation, and congenital malformations.
There are important differences between the adult and pediatric head-and-neck region that need to be accounted for in reconstruction. Generally, the skin of a child’s face has increased elasticity and is growing with growth centers located throughout the facial skeleton. The lack of sun damage and rhytids along with indistinct borders between aesthetic subunits makes it more difficult to adequately hide a surgical scar in the pediatric population.
The goal of any reconstruction is to restore functionality and provide an aesthetic result with minimal donor site morbidity. 4 The reconstructive ladder is a useful concept utilized in the pediatric population to characterize and assess the degree of treatment required. 5 When possible, reconstruction with primary closure should be performed. Secondary intention healing is slow and may lead to contractures, scarring, and restriction of movements. In children, adjuncts to facilitate reconstruction of large defects may include temporary closure with skin grafting and placement of tissue expanders to recruit additional tissue to allow local flap transfer. Tissue expansion is a powerful surgical modality that can be especially useful in growing skin and soft tissue in the pediatric population. 6 Rather than replacing tissue, tissue expanders are placed under adjacent tissue with slow expansion to allow for secondary local flap procedures to provide improved aesthetic results. Given that pediatric patients, when compared to adults, have a scarcity of usable tissue, the implementation of pretransfer expansion of donor sites to increase the amount of available tissue is a helpful tool in the reconstruction of large defects (▶ Fig. 56.1). Although children have thinner and less available soft tissue for expansion, their skin inherently has a better blood supply and is more easily expandable than that of adults. Nevertheless, a recent study suggested there is no difference in complication rates between adult and pediatric populations who underwent tissue expansion. 7
Local flaps are the workhorse for reconstruction of pediatric craniofacial defects and will be discussed in detail in this chapter. If adequate local tissue is not available, the use of a regional flap may allow for closure of larger defects and will also be reviewed below. However, large regional flaps (e.g., pectoralis myocutaneous flaps) are used less often due to significant donor and recipient site morbidity and poor aesthetic outcomes. With the advent of free tissue transfer, microvascular reconstruction has surpassed regional flaps as the preferred reconstruction for large or composite defects in the pediatric population. This chapter will focus on more commonly used local and regional flap reconstruction in the pediatric population.
56.2 Local and Regional Flaps
A local flap is defined as transfer of skin and subcutaneous tissue with its blood supply to an immediately adjacent defect. It is important when designing a local flap to try to minimize wound closure tension by utilizing skin extensibility when recruiting skin and to align resultant scars along the borders of subunits or parallel to the relaxed skin tension lines. 8 The definition of a regional flap is less concise and debated. Although many authors consider a flap that is not adjacent to the defect to be a regional flap, the true definition of a regional flap is a pedicled flap from outside the head-and-neck region. Regional flaps are typically reserved for defects which cannot be adequately reconstructed with the sole use of a local flap and are used far less often than local flaps, particularly in the pediatric population, as they are associated with a higher donor site morbidity and tend to have worse aesthetic outcomes with poor tissue match. 9 Additionally, for large or composite pediatric facial defects, free tissue transfer has largely replaced regional flap reconstruction.
Regardless of the definition utilized, local and regional flaps may be classified in many different ways (▶ Table 56.1). Flaps may have a random pattern design in which the vascular supply is from the dermal and subdermal plexus or an axial design based off a named arterial supply in the subcutaneous fat. They may rotate, advance linearly, or use a combination of these movements to fill a defect. The secondary defect caused by the flap is then closed primarily. Flaps may also be transposed over or under an intact bridge of skin, typically requiring a secondary procedure to divide the vascular supply. Local and regional flaps have large clinical value in head-and-neck reconstructions as the vascular conditions in the region allow for excellent viability along with superior color and facial skin quality match. 10
Method of transfer
Random pattern Based off of dermal and subdermal plexus from perforators
Axial pattern Based off of a named vessel typically in the subcutaneous tissue
There are many factors that play a role in the selection of a reasonable flap, including the size and location of the defect and the intrinsic viability of the flap. 8 , 11 Although both categories of flaps are relatively safe and reliable, they do have a risk of postoperative complications such as wound infection, hemorrhage, hematoma, flap loss with necrosis, and poor cosmetic outcomes with need for revision surgery. Although a detailed discussion of every possible flap is beyond the scope of this chapter, the more common local and regional flaps used in pediatric headand-neck reconstruction will be reviewed.
56.3 Cervicofacial Flap
The cervicofacial flap is a random pattern local flap that recruits soft tissue from surrounding facial and cervical skin to reconstruct moderate (1.5 cm) to large defects (>3.0 cm) of the cheek, periorbital region, temple, and posterior neck. 12 , 13 It typically incorporates a combination of rotation and advancement movements. Incisions are placed in borders of subunits or existing rhytids to minimize visibility of scars. This flap is classically elevated in a subcutaneous plane but may be modified by dissecting the flap in a deeper, subsuperficial musculoaponeurotic system (SMAS) and subplatysmal plane to enhance flap thickness, increase the vascular supply, and improve viability of the flap (▶ Fig. 56.2a–d). 14 , 15 The surgeon may elevate the entire flap deep to the SMAS in the face and platysma in the neck or may choose to elevate in a subcutaneous plane in the face and deep to the platysma in the neck. Regardless of the preferred level of elevation, the surgeon should stay superficial to the parotidomasseteric fascia and care should be taken when elevating anterior to the anterior border of the parotid gland to protect distal branches of the facial nerve.
The cervicofacial flap provides several advantages in facial reconstruction aside from those related to an enhanced blood supply. It offers an excellent cosmetic profile including good skin texture, color, and flexibility match to the recipient skin. This is particularly useful in the pediatric population because of the relative importance of appearance in the psychosocial development of a child. Second, the mobile nature of the flap makes it a more reliable and adaptable option in reconstructive efforts. Finally, the cervicofacial flap can be employed in conjunction with procedures that require simultaneous parotidectomy or facial reanimation. This flap typically results in a standing cutaneous deformity. Although this can often be safely removed at the time of initial surgery, care should be taken not to narrow the flap base as this will exacerbate vascular insufficiency.
A major drawback of the extensively mobilized cervicofacial flap is the risk of distal flap necrosis secondary to compromised blood supply. 12 , 15 This risk is minimized in children as there are fewer comorbidities such as smoking or diabetes. Flap necrosis in children may occur due to hematoma, thin flap elevation, infection, or excessive tension. Minimizing wound closure tension is also key to decreasing the risk of widened, unattractive, or hypertrophic scars.
56.4 Scalp Rotation Flap
The scalp is a richly perfused multilayered region of the head that can be strategically rotated to reconstruct hair-bearing defects of the head and neck. The major contributing vessels are the supratrochlear, occipital, supraorbital, superficial temporal, occipital, and posterior auricular arteries. 16 The scalp is relatively inelastic and stiff relative to other facial tissues and therefore requires a larger flap to be harvested than from other areas of the face. If necessary, the entirety of the scalp may be elevated and rotated, or multiple rotation flaps may be employed depending on the size and location of the defect. The scalp flap may be elevated in either a subgaleal or subperiosteal plane depending on the defect characteristics. The indispensable nature of the scalp, mostly due to the fibrous galea aponeurosis, serves a beneficial means of attenuating the distension of the pertinent vasculature which may otherwise compromise the viability of the tissue. 16 If necessary, galeotomies or incisions in the pericranium may be created to aid in the rotation of this flap.
Scalp rotation flaps are most commonly used to treat defects secondary to tumor resection, congenital abnormalities, osteomyelitis, and traumas/burn injuries. 17 The scalp rotational flap is a relatively simple and quick technique in repairing small and moderate defects of the head. It is especially valuable because of the excellent color, skin, and texture characteristics of the scalp tissue. This flap is useful to reconstruct a defect at the hairline and may be combined with facial flaps to optimize results (▶ Fig. 56.3a,b).
Careful attention must be given when working with scalp rotational flaps on the pediatric population. Although the scalp has a vigorous blood supply, long axial flaps are at a higher risk of necrosis in children because the galea aponeurosis is not fully developed, which puts the relevant vasculature in jeopardy of distension and stretching. 16 In addition, the lack of distensibility in the scalp may necessitate supplementary skin grafting for donor site closure. 18 Scalp expansion is a useful adjunct to increase the amount of available tissue for rotation prior to reconstruction and allow primary closure of donor site. Excessive stretch on the scalp may lead to temporary hair loss due to telogen shock, which may take months to show regrowth. This flap also redistributes hair and may cause alterations in the direction of hair growth. Other risks of surgery include hematoma, adverse scarring with alopecia, and numbness of the scalp.
56.5 Geometric Flaps
Geometric flaps tend to be rotational and transposition random pattern flaps based off of the subdermal vascular plexus. They incorporate distinct geometric shapes in the planning and execution of the flap. Although useful for reconstructions of the temple, cheek, and nose in adults, they are used less frequently in children due to the inability to hide the geometric scars and local tissue distortion. 14 Although relatively simple to execute, the geometric flaps require careful assessment and planning as incisions cannot be placed within relaxed tension lines or along subunit borders which may elicit high degrees of tension at the closure point and lead to adverse scarring. These flaps also require excision of standing cutaneous deformities, which may be addressed at the time of flap transposition.
A major advantage in the use of these flaps is preservation of the skin characteristics of the recipient site. In addition, they offer greater flexibility in the use of available tissue when compared to many other local flaps. With respect to the pediatric population, the bilobed and rhombic flaps are rarely used due to irregularity and prominence of scars in conjunction with the inability to place scars along aesthetic subunits.
56.5.1 Bilobe Flap
The bilobed flap consists of two lobes that recruit tissue from areas of increased skin mobility. The first lobe is adjacent to the defect, is generally the same size of the defect, and may incorporate a 45° to 90° arc of rotation depending on the design. The second lobe may be half of the width of the defect and also incorporates a 45° to 90° arc of rotation. 8 , 19 , 20 The flap is elevated in a supraperichondrial plane in the nose and a subcutaneous plane in the cheek and neck and transposed into the defect. It should be noted that a standing cutaneous deformity will have to be excised at the base of the defect adjacent to the first lobe.