Locoregional Flaps for Oral Cavity Reconstruction: A Review of Modern Options

Supraclavicular Flap

A random pattern flap in the supraclavicular (SC) region was originally described by Mütter ¹ in 1842, although it was not until 1997, when it was “rediscovered” by Pallau et al, ² that it became widely appreciated. Earlier descriptions of the flap use the term in charretera or epaulet in that the flap occupies the region where soldiers traditionally wear their ornamental shoulder pieces. ³ The SC flap gained popularity in the treatment of postburn mentosternal contractures but more recently has been shown to have myriad applications throughout the head and neck.

The SC flap is based on the SC artery, which arises 3 to 4 cm from the origin of the transverse cervical artery in 93% of cases and the suprascapular artery in the remaining cases. The artery averages 1.33 mm in diameter. The flap is drained by 2 veins: one entering the transverse cervical vein and the other entering either the external jugular vein or subclavian vein.^4,5 The takeoff of the SC artery can be reliably identified with a Doppler probe placed in a triangle formed by the dorsal edge of the sternocleidomastoid muscle, the clavicle, and the external jugular vein. The angiosome supplied by the pedicle has a mean length of 24.2 cm, a mean width of 8.7 cm, and a mean surface area of 152.8 cm². ⁶

Harvest of the flap begins with the identification of the SC artery in the SC fossa with a Doppler probe and tracing it over the distal third of the clavicle and over the deltoid ( Figure 1 ). An appropriately sized skin paddle is centered over the artery and is optimally placed over the anterior axillary line rather than over the lateral aspect of the deltoid. ⁷ The flap can be harvested as an island flap and tunneled into the defect, or an incision may extend to communicate with the wound. Harvest is initiated incising around the skin paddle. The flap is elevated distally to proximally in a subfascial fashion. As elevation proceeds over the clavicle, the periosteum may be incised and elevated to protect the delicate pedicle. ⁷ Within the SC fossa, it is recommended to leave a cuff of soft tissue around the pedicle rather than skeletonizing it. This can be accomplished with a combination of Doppler identification over the course of the pedicle and division of the surrounding fascia. This greatly facilitates the harvest, protects the pedicle, and provides a soft tissue cushion to prevent kinking. As dissection reaches the transverse cervical vessels, a large ark of rotation is achieved. The flap may be elevated without rotation of the pedicle to reconstruct mucosal defects or rotated 180 degrees to exteriorize the flap for cutaneous defects. Wide undermining of the shoulder skin allows for primary closure in the majority of cases of the donor defect, although a skin graft may be applied if necessary as well. A video illustrating the harvest can be accessed at www.ahns.info/resources/education/video/surpraclavicular-flap-video. ⁸

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Figure 1.

(A) Supraclavicular flap skin paddle over anterolateral aspect of left deltoid. (B) Flap elevated with a wide swath of tissue around the vascular pedicle. (C) Oral cavity defect in anterior alveolar ridge of mandible and floor of mouth. (D) Skin paddle transferred to mouth and inset into oral defect.

Myriad applications for the SC flap have been described, including parotidectomy-associated contour deformities; release of postburn mentosternal contractures; resurfacing progressive hemifacial atrophy; management of tracheocutaneous fistulas; reconstruction of posterior pharyngeal wall defects; sternal wound coverage; reconstruction of pharyngeal, oromandibular, auricular, temporal bone, and posterolateral skull base defects; and pharyngectomy/laryngectomy defects with primary tracheoesophageal prosthesis placement.^9-20 Furthermore, the versatility of the flap has been demonstrated with numerous modifications, including tunneled island flaps, bilateral supraclavicular flaps, supercharged flaps, extended flaps, prefabricated/delayed flaps, preexpanded flaps, and osteocutaneous flaps.

The SC flap is ideal for head and neck reconstruction is that it uses “like” skin to reconstruct head and neck defects, offering a color match unrivaled by most free flaps. The flap is thin, pliable, and usually hairless; has a large ark of rotation; can be harvested in less than 1 hour; has minimal donor site morbidity; and does not require a second team or microvascular expertise. ²¹

One must have caution in patients with previous neck dissections to ensure that the transverse cervical and supraclavicular arteries are present. Stigmata of previous radical neck dissection should alert the surgeon to choose a different flap. In addition, patients with vasculopathies (eg, diabetes, tobacco abuse) are more likely to have complications with flap necrosis. The SC flap is not favorably suited for complex 3-dimensional defects such as those involving the tonsillar fossa, palate, and base of tongue as the multiple folds increase the likelihood of necrosis. Distal tip necrosis ranges from 4% to 18%, complete necrosis from 0% to 4%, and donor site dehiscence around 10% in larger series. ²²

A recent study retrospectively compared 18 SC flaps to 16 radial forearm flaps (RFFs) in head and neck reconstruction. ²³ The SC flaps were found to be significantly larger and required shorter operative times, and patients had shorter intensive care unit (ICU) stays. There was no significant difference in morbidity between the flaps, leaving the authors to conclude that the SC flap is the first choice for fasciocutaneous reconstruction in the head and neck.

Submental Flap

The submental island artery flap has become increasingly popular since its introduction by Martin ²⁴ in 1993. Its use in head and neck reconstruction has been previously described and has been shown to be well suited for defects of the oral cavity.^25-31 The submental flap is based off the submental artery, which is a consistent branch of the facial artery. It is roughly 1.0 to 1.5 mm in diameter at its takeoff from the facial artery. ²⁵ In 70% of cases, it runs deep to the digastric and just superficial to the mylohyoid muscle as it enters level Ia of the neck. It passes superficial to the digastric in the remaining 30% of cases. Cadaveric dissections have shown that there can be as few as a single reliable perforator per side, and the location of this can be either medial or lateral to the anterior digastric muscle.^26,29

The design and harvest of the flap are well described in prior published work and will be summarized here. ²⁷ The upper border of the flap is drawn at the inferior border of the mandibular arch ( Figure 2 ). The maximal width of the flap is determined by a pinch test to assess how much donor site can be closed primarily. The length is designed according to the defect and can span from mandibular angle to mandibular angle if necessary. The skin paddle incision can be designed to incorporate unilateral or bilateral neck dissection.

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Figure 2.

(A) Submental flap skin paddle design. (B) Flap mobilized with ipsilateral geniohyoid (thin arrow) and contralateral digastric in view (thick arrow). (C) Flap tunneled through submandibular triangle into defect. (D) Donor site closed primarily.

The inferior aspect of the skin paddle and neck incision is incised down through the platysma muscle. An excision of the submandibular gland is performed with attention to the submental vessels on the superior surface. Once the gland is removed, the entire course of the submental vessels can be seen up to the lateral border of the mylohyoid muscle. At this point, lymph nodes in level IB can be safely dissected away from the submental vessels to achieve a thorough lymphadenectomy for these levels of the neck. While these level IB nodes may be safely dissected away from the vascular pedicle and removed, clinical or radiographic evidence of level IA disease carries a relative contraindication from proceeding with this reconstructive option.

The submental flap is then raised from the contralateral side in a subplatysmal fashion. Upon reaching the midline, the dissection is carried deeper into level Ia down through the mylohyoid muscle. A useful modification is to include the mylohyoid muscle in the flap as the deep border. By including the mylohyoid, the submental artery and the perforating vessels remain protected at all times in this delicate area. A wide arc of rotation is increased by more proximal dissection if required. If even greater rotation is needed, the branches of the facial vessels crossing the mandible can be ligated. The anterior neck skin is undermined for wound closure. A video illustrating the submental flap harvest can be accessed at http://www.ahns.info/resources/education/video/submental-island-flap-harvest. ³²

The submental flap offers thin, pliable tissue that can reach most areas of the oral cavity. It can be used for floor-of-mouth, lateral tongue, alveolar ridge, and buccal defects with very little difficulty. When used intraorally, it remains hair bearing in most male patients. The flap can be de-epithelialized at the time of inset to eliminate the hair follicles surgically. ³¹ To improve its reach in some of these areas, the common facial artery and vein can be ligated proximal to the takeoff of the submental vessels and the flap fed and drained in a retrograde fashion through the face.

Caution must be exercised in patients who have already received prior treatment. If a neck dissection has been performed ipsilateral to the intended pedicle, it is likely that the submental vessels have already been compromised. In patients who have been treated with radiation therapy, the flap can be safely elevated, although this incidence of distal flap loss may be higher.

The submental flap has been compared with the radial forearm free flap for oral cavity reconstruction. ²⁸ In a retrospective study of 60 patients, the submental flap performed favorably. The median size of the submental flap was 5 × 7 cm compared with 6 × 8 cm for the radial forearm, demonstrating that a roughly comparable territory of tissue could be harvested. Operative time and hospital stay were both significantly shorter for patients who underwent submental flap reconstruction. Functional outcomes were similar as was oncologic outcome. A larger retrospective study specifically looked at the oncologic safety of the submental flap when used for oral malignancy and found that use of this reconstructive option did not compromise oncologic outcome. ³³

Facial Artery Musculo-Mucosal Flap

The FAMM flap is an option for reconstructing small- to medium-volume defects of the oral cavity and oropharynx. Defects of the anterior and posterior palate, nasal septum, floor of mouth, ventral tongue, and both upper and lower lip are suited to reconstruction with the FAMM flap. This flap was first described in 1992 by Julian Pribaz et al ³⁴ and has become more popular in recent years given broader recognition of the utility of this flap in conjunction with a better understanding of harvest technique. This flap is not to be confused with the buccinator musculo-mucosal flap described by Bozola et al ³⁵ and is based posteriorly from the buccal artery branch of the internal maxillary artery.

The facial artery musculo-mucosal flap or FAMM flap has the advantage of providing vascularized full-thickness mucosal reconstruction with a long arc of rotation. This allows “reach” to areas that otherwise present challenges using other locoregional flaps and even free flap options. The FAMM flap can be either inferiorly or superiorly based and includes mucosa, submucosa, buccinator muscle, and the facial artery. Although the flap has an axial pattern arterial supply, venous drainage is random and is accomplished through the venous network present within the submucosal base of this flap. For this reason, this flap is sometimes described as arterialized rather than axial. ³⁶ Although the facial vein is in close proximity to the facial artery at the point where the artery crosses the inferior boarder of the mandible, the 2 vessels then diverge with the vein coursing posteriorly. As a result, the facial vein courses beyond the confines of this flap whether the flap is superiorly or inferiorly based. Although the facial artery runs superficial to the buccinators and deeper fibers of the orbicularis oris, it is deep to the remaining muscles of facial animation, and for this reason, the flap can be harvested with minimal risk to facial nerve musculature. The facial artery generally maintains good caliber as it ascends above the mandible with an average diameter of 2.6 mm at the inferior border of the mandible and a diameter of 1.6 mm at the alar base. ³⁷ In 2% to 11% of persons, the facial artery is hypoplastic and the potential for flap failure may be higher in this group, particularly for superiorly based flaps.

The basic technique involved in harvest of this flap consist of first mapping out the path of the facial artery transorally with a handheld Doppler as it passes from the second mandibular molar inferiorly to the level of the nasal alar base superiorly ( Figure 3 ). The flap will have an oblique and slightly curved course with the posterior limb located anterior to the Stenson’s duct orifice and the anterior limb at least 1 cm posterior to the oral commissure. This 1-cm margin between commissure and flap is important to avoid distortion of the oral commissure with primary closure of the donor site defect. Most flaps will have a width between 2 and 3 cm, with the distal end being slightly narrower than the base. The base of the flap must be at least 2 cm in width to allow adequate venous drainage through the buccal submucosa. Once the flap dimensions have been determined, dissection begins either at the distal end of the flap or the anterior border of the flap. In each instance, the mucosa, submucosa, and buccinator muscles are divided and the facial artery is identified. The artery is then ligated at the distal end of the flap. The flap can be raised such that the artery is maintained in the approximate center of the flap with a cuff of buccinator muscle on either side of the artery and the width of mucosa and submucosa above the muscle. At the level of the oral commissure, this will include some of the deeper fibers of the orbicularis oris, but this will not result in oral sphincter weakness given that the remaining muscle is superficial to the artery. Once fully mobilized, the donor site is typically closed primarily.

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Figure 3.

(A) Superiorly-based facial artery musculo-mucosal flap design, with “Xs” delineating path of facial artery. (B) Facial artery isolated. (C) Flap elevated with artery along axis of flap. (D) Flap inset into lip defect, with donor site closed primarily.

In general, superiorly based flaps are suited to anterior palate, nasal septum, alveolus, and upper lip. If the dentition of the maxillary arch is crossed with this flap, a bite block is employed to avoid masticatory trauma to the base of the flap. Inferiorly based flaps are ideal for posterior palate, floor of mouth, alveolus, and lower lip. Again, bite blocks must be used when crossing intact dentition.

Ayad and Xie ³⁸ published a systematic review of all FAMM flap series over a 20-year interval with a total of 441 FAMM flaps. In this review, complications of partial necrosis of the distal flap occurred in 12.2% and complete necrosis occurred in 2.9%. Superiorly based flaps are well suited for anterior cleft palate repairs, and this is one site that presents challenges with other reconstruction options. In head and neck oncology, inferiorly based flaps are most often used for reconstruction of floor-of-mouth defects. In a series by Ayad et al, ³⁹ 61 patients had floor-of-mouth reconstruction with this flap, and 38 of these 61 patients had a second stage division of the flap base at an average of 52 days after the first stage (range, 13-189).

The advantages of this flap include ease of harvest, a mucosal surface, and low donor site mobility without additional external scarring. The disadvantages include limited size and the frequent need for a 2-stage reconstruction. It is for this reason that the flap is most ideally used in reconstruction of defects lateral to the mandibular or maxillary arch as in the case demonstrated by Figure 3 . Although the flap has been described as an island flap or even as a free tissue transfer,^40,41 we believe that these variants will have a higher rate of failure overall.

Pectoralis Flap

The pectoralis major myocutaneous (PMMC) pedicled flap was first described for head and neck reconstruction by Ariyan ⁴² in 1979. More versatile and reliable compared with prior techniques, such as random pattern flaps and the deltopectoral flap, the pectoralis major flap revolutionized head and neck reconstructive surgery and served as the workhorse flap for the majority of head and neck oncologic defects encountered until microvascular free flaps became commonplace. While the pectoralis major muscle flap has a reputation as being highly reliable, the PMMC flap’s skin paddle has been reported to have a partial necrosis rate of 15% to 27%. ⁴³ However, greater understanding of the vascular anatomy of the flap can allow the reconstructive surgeon to design the pectoralis major pedicled flap with the maximum reach and reliability while minimizing contracture and the bulge in the neck.

The dominant blood supply of the pectoralis major muscle is the pectoral branch of the thoracoacromial artery, and secondary blood supply includes the lateral thoracic artery and branches of the internal mammary artery as well as perforating branches of the anterior intercostal arteries. The lateral thoracic artery follows the lateral border of the pectoralis minor muscle and supplies the lateral part of the pectoralis major muscle. A separate flap comprising the lateral portion of the pectoralis major muscle can be harvested based on this artery. ⁴⁴ The venous drainage is via paired venae comitantes that accompany the arteries.

The main blood supply to most of the skin overlying the pectoralis major muscle comes from the musculocutaneous perforating branches of the internal mammary artery in the second through sixth intercostal spaces, medially, and the musculocutaneous perforating branches of the third through sixth anterior intercostal arteries, laterally. These perforators are connected to the thoracoacromial artery pedicle via anastomotic “choke” vessels that dilate once the flap has been elevated and they have been disconnected from their original primary blood supply. The pectoral branch of the thoracoacromial artery also supplies small perforating branches to the skin overlying its course, although the artery dissipates at about the level of the fourth rib.

To design a PMMC flap with the greatest reach, the skin paddle should be centered over the inferior portion of the pectoralis major muscle. This is outside the vascular territory of the musculocutaneous perforating branches of the thoracoacromial artery, but the skin paddle remains well perfused because of the high density of musculocutaneous perforating branches that originate from anterior intercostal blood vessels of the fourth, fifth, and sixth costal interspaces but are in communication with the thoracoacromial artery via choke vessels ( Figure 4 ). ⁴⁵ In particular, centering the skin paddle over the fourth intercostal space, where the largest perforators typically occur, results in a high degree of reliability. Since adopting this design, we have not witnessed a single instance of partial or total necrosis of the skin paddle.

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Figure 4.

(A) Pectoralis myocutaneous flap design. Doppler signal marks skin perforator. (B) Intercostal vessel ligated for flap harvest. (C) Flap elevated and passed beneath skin tunnel to mouth. (D) Skin paddle is inset to the oral defect.

When harvesting a PMMC flap, dissection of the muscle is performed through the skin paddle incision. If a pectoralis muscle flap is being elevated, an incision within the inframammary fold in women or along the inferior border of the pectoralis major muscle in men is planned. In addition to the access afforded by the skin paddle incision (in the PMMC flap) or an inframammary incision (in the pectoralis muscle flap), it is often helpful to make a counter incision just below and parallel to the clavicle when the flap is used in head and neck reconstruction for surgical exposure. While a vertical or oblique incision could be made over the pectoralis muscle, the recommended transverse incisions are preferable since they preserve the skin over the second and third intercostal spaces, which could be used for a deltopectoral or internal mammary artery perforator flap.

Care is taken to ligate rather than cauterize perforating blood vessels arising from the intercostal spaces, since these communicate directly with the skin paddle after they course through the thickness of the muscle. The thoracoacromial pedicle should be identified early, on the undersurface of the muscle. The proximal muscle is divided with electrocautery superior to the skin island, and the muscle portion of the flap is “narrowed” overlying the pedicle. This detaches the flap from both the humerus laterally and the sternum medially. Also, by narrowing the flap, the internal mammary artery perforators are spared, preserving the blood supply to the deltopectoral/internal mammary artery perforator flap and avoiding potential bleeding by accidentally injuring these blood vessels. Proximally, minimal muscle needs to be left over the pedicle, and in fact, the pedicle can be completely dissected from the muscle with appropriately delicate technique to minimize bulk and also prevent contracture that can limit neck movement or pull the flap away from where it is inset into the defect being reconstructed. The lateral thoracic artery lies lateral to the thoracoacromial artery and does not need to be included with the flap if the maximum arc of rotation is required to reach the defect. The medial and lateral pectoral nerves are also divided to maximize reach and decrease contracture due to muscle contraction.

In obese patients and in women due to the presence of the breast, a skin paddle may be excessively bulky, and harvest of a PMMC flap may also significantly distort the breast shape. In such cases, consideration should be given to performing a pectoralis major muscle flap and covering it with a split- or full-thickness skin graft. An alternative would be to center the skin paddle superomedially, over the internal mammary perforators in the third intercostal space, where there is usually less soft tissue bulk. ⁴⁶ These skin perforators are also connected to the thoracoacromial artery pedicle via chock vessels. However, designing the skin paddle in a more proximal location shortens the reach of the flap. While a reliable skin paddle could also be designed directly over the thoracoacromial artery, such a flap would have even less reach.

Temporoparietal Fascial Flap

The versatility of the TPFF has been seen in its use in a variety of ablative defects. ⁴⁷ In 1898, Brown ⁴⁸ first described the use of TPFF for reconstruction of the external ear after a horse bite, while Monks ⁴⁹ similarly described its use for lower eyelid reconstruction. However, it was not until the mid-20th century when surgeons began understanding the anatomy and expanding its utilization. In 1985, Brent et al ⁵⁰ reported the successful use of the flap as an axial-pattern fascial flap, a random-pattern fascial flap, and a free fascial flap for secondary ear reconstruction. In 1993, Cheney et al ⁵¹ described 21 cases using the flap for a variety of reconstructions in the head and neck.

The TPFF provides a thin and pliable reconstructive tissue ideal for a variety of head and neck defects.^52,53 The TPFF is supplied by the superficial temporal artery (STA), which arises from the external carotid artery and runs a tortuous course in the preauricular area. Approximately 3 cm above the zygomatic arch, the STA divides into terminal frontal and parietal branches. The outflow of the TPFF is provided by the superficial temporal vein, which generally runs superficial to and with the STA; however, this can be variable. ⁵³

The frontal (temporal) branch of the facial nerve is at risk during the harvest of the TPFF. It lies within the temporoparietal fascia (TPF) and traverses obliquely over the zygomatic arch, which can be estimated by a line connecting a point 0.5 cm inferior to the tragus to a point 1.5 cm lateral to the superior brow. The frontal branch generally parallels the frontal division of the STA, although nerve fibers can interweave and pass superior to the artery. ⁵³

The surgical technique for harvest has been well described in the past.^50-54 The course of the STA is identified using a Doppler probe in the preauricular area, and the approximate course of the frontal branch of the facial nerve can be marked out as described above ( Figure 5 ). The anterior and posterior scalp flaps are elevated in the subcutaneous plane immediately deep to the hair follicles. The TPF adheres to this subcutaneous tissue, and sharp dissection is necessary to avoid injuring either the vascular supply of the flap or the hair follicles. After elevation of the skin flaps, the superior, posterior, and anterior limits of the flap are made. A nerve stimulator is useful in identifying the course of the frontal nerve. Superiorly, the TPFF can be extended beyond the temporalis muscle to incorporate the pericranium, thus extending the length of the flap. The vascular pedicle is identified and the flap base is narrowed to 2.0 to 2.5 cm. The maximal size of the flap is 17 × 14 cm with an average width being 2 to 3 cm. ⁵⁵

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Figure 5.

(A) Temporoparietal fascia flap design. Line denotes course of frontal branch facial nerve. (B) Flap elevated off temporalis bed. (C) Flap flipped inferiorly to confirm arc of rotation. (D) Flap tunneled subcutaneously to palate defect.

Use of the TPFF for oral cavity defects has been described by Nayak and Deschler, ⁵⁴ Upton et al, ⁵⁶ and Pinto et al. ⁵⁷ Upton et al ⁵⁶ described the successful use of a pedicled TPFF in 2 patients who had oronasal fistulas and 1 patient with lye ingestion. In their series, they used a 2-stage approach where a skin graft was placed over the TPFF approximately 3 to 4 weeks after. Nayak and Deschler ⁵⁴ presented 3 patients after oncologic ablative surgery undergoing a single-stage TPFF reconstruction of the oral cavity. Two patients had a buccal defect and 1 had a superior alveolar ridge defect. Pinto et al ⁵⁷ described the use of a single-stage TPFF in 6 patients with oral defects. They reported no flap losses, with the reconstructive goal achieved in all cases. In all 3 series, a tunnel is created at the level of the zygomatic arch wide enough to avoid compression of the vascular pedicle and posteriorly enough to avoid injury to the frontal branch of the facial nerve.

The complications related to TPFF reconstruction of the head and neck are rare. Risks include alopecia, frontal branch paresis or paralysis, flap necrosis, and hematoma. It should also be noted that since this flap does not carry an epithelial surface, granulation and remucosalization are a necessary step in the process. Accordingly, there can be some degree of scarring or contracture as is sometimes seen with buccal reconstruction using this flap. Previously described meticulous technique and understanding of the anatomy can often prevent these complications. ⁵⁶

Implications for Practice

A wide range of options exist for oral cavity reconstruction, ranging from primary closure to free tissue transfer. Regional reconstructive options often offer ideal raw materials for good functional and aesthetic reconstruction while avoiding various demands placed on the patient and the health care system that are required for free tissue transfer. The authors believe the above techniques augment the range of action of the head and neck reconstructive surgeon when dealing with oral cavity defects. Choice of reconstructive technique must be specific to a particular patient and accompanying defect. With the above techniques, surgeon can offer a wider range of options that may afford a more tailored plan for each patient. With increasing emphasis on high-quality, cost-effective medical care, these advances in regional reconstruction should play a greater role in the overall landscape of oral cavity reconstruction.

Author Contributions

Urjeet A. Patel, design, drafting content, final approval, accountable for all aspects; Gregory K. Hartig, design, drafting content, final approval, accountable for all aspects and any questions investigated/resolved; Matthew M. Hanasono, design, drafting content, final approval, accountable for all aspects and any questions investigated/resolved; Derrick T. Lin, design, drafting content, final approval, accountable for all aspects and any questions investigated/resolved; Jeremy D. Richmon, design, drafting content, final approval, accountable for all aspects and any questions investigated/resolved.

Disclosures

Competing interests: Derrick Lin received research grants from AstraZeneca, AbbVie, and Tesaro.

Sponsorships: None.

Funding source: None.