Pharynx

• Mandibular

• Craniofacial

• Scalp and cranium

Defect

Depth

The depth of the defect is an important factor determining which category of the reconstructive ladder (skin graft vs. flap) can be used. If there is adequate subcutaneous tissue or a perfused wound, skin grafts either split thickness or full thickness are possible. They can be used for oral or nasal mucosal defects to provide inner lining. However, even if a skin graft is technically possible for external defects such as in the face, flaps achieve a better cosmetic outcome and are therefore preferred.

Size

The size of a defect is an important factor determining within one category of the reconstructive ladder which skin transplant (split thickness vs. full thickness) or which flap (local vs. single free flap vs. combined free flap) can be used.

Full-thickness skin grafts can only be used in smaller defects, as the availability is limited as outlined above. There is no size limitation for the use of split-thickness skin grafts.

Small defects in the face, on the skull, or neck as well as mucosal defects can be reconstructed by local or regional flaps. Larger defects require a free flap. Again the size of the defects determines whether a required cutaneous free flap can be a radial flap or needs to be bigger such as an anterolateral thigh flap or even a combined scapular/parascapular flap. For muscular requirements, a small defect might be closed by a gracilis flap, a larger defect may require a rectus abdominis or even a latissimus dorsi muscular or mus-culocutaneous free flap.

Location/functional Impairment

The site of reconstruction in the head and neck largely influences the associated functional impairment and thus reconstructive requirements.

Oral Cavity

Defects of the oral cavity affect eating, chewing, food movement, maintaining oral continence, and the initiation of swallowing and speech formation. It requires reconstruction of an inner (mucosa) and outer lining (skin).

Reconstruction of the oral cavity is a matter of flap reconstruction,10 the role of skin grafts is only supplementary, for example, to reconstruct an inner lining on a transplanted free flap.

The Radial Forearm Flap

In 1981, Yang described the radial forearm flap and it is therefore referred to as the Chinese flap.11,12 It is the most commonly used free flap to the head and neck. The flap is harvested on the radial artery and its venae comi-tantes. The cephalic vein can be additionally taken to augment venous drainage. The radial forearm flap provides a large, thin, pliable, and predominantly hairless flap for intraoral and oropharyngeal lining (Figs. 17-4 and 17-5). The skin has the capacity to become sensate with microanastomosis of the ante-brachial cutaneous nerve. Bone or tendons can be included to provide oral support such as in lower lip reconstruction. Furthermore, its pliable skin allows for the folding and contouring that are necessary to recreate the nasopha-ryngeal sphincter and the conduit to the hypopharynx. Before harvesting the radial artery, adequate collateral ulnar artery circulation has to be confirmed either preoperatively by an Allen test (manual occlusion and sequential release of radial and ulnar vessels at the wrist) or intraoperatively by clamping the radial artery before dissection. However, donor site problems are well recognized particularly an unsightly donor site defect which is usually skin transplanted.

Figure 17-4 A 43-year-old male patient with an intraoral SCC. (A) Preoperative; (B) after tumor extirpation; (C) donor site at the forearm showing a radial forearm flap; (D) intraoperative view after inset of the flap; (E) postoperative intraoral view after 1 year.

Figure 17-4 (Continued)

Figure 17-5 (A) A 73-year-old patient with a recurrent malignant melanoma and a history of split-thickness skin graft and radiation; (B) midfacial defect after tumor resection; (C) outline of the radial forearm flap; (D) flap in place; (E) result after 1 year without any revision surgery of the flap.

Figure 17-5 (A) A 73-year-old patient with a recurrent malignant melanoma and a history of split-thickness skin graft and radiation; (B) midfacial defect after tumor resection; (C) outline of the radial forearm flap; (D) flap in place; (E) result after 1 year without any revision surgery of the flap.

Figure 17-5 (Continued)

The Scapular Flap/parascapular

An alternative adipocutaneous flap is the scapula flap which is located over or at the lateral border of the scapula. It is supplied by the arterial system of the subscapular artery, which branches in the circumflex scapular (supplying scapula/parascapular flap) and the thoracodorsal artery (supplying the latis-simus dorsi flap). The flap can be larger than the radial artery flap. The donor site can be hidden. A disadvantage is that the patient may need to be turned intraoperatively.

The lateral arm flap13 is a further alternative providing a thin adipocuta-neous flap from the lateral aspect of the upper arm. It is smaller than the radial artery flap but the donor site is usually more acceptable.

The anterolateral thigh flap14 provides a large and thin cutaneous flap based on the descending branch of the lateral circumflex femoral artery. The dissection is more difficult than with the radial forearm flap, but it is increasingly becoming popular.

Second-line options are pedicled flaps, such as the pectoralis major, pedi-cled latissimus, or deltopectoral flap. The deltopectoral flap is located on the upper chest ranging from the sternal border up to the deltoid muscle. The first four perforating branches of the internal mammary artery supply the flap. It is an adipocutaneous flap that can reach up the oral cavity for reconstruction.

Glossal Defect

It has been shown that speech is a primary factor determining quality of life. Quality and intelligibility of speech largely depends on tongue mobility. Furthermore, the tongue serves swallowing and airway protection. To restore these functions it requires a bulky, voluntary mobile and possibly sensate flap. The goals are almost impossible to achieve.

Regional flaps such as the pectoralis major musculocutaneous flap have been described for tongue reconstruction. However, free flaps have become the method of choice. Various flaps have been described such as the radial forearm flap, the free groin flap, or anterolateral thigh flap. As outlined above, a bulky flap is favorable for tongue reconstruction, so with all of these flaps, muscle has been incorporated such as the brachioradialis muscle in the forearm flap, the sartorius in the groin flap, or the vastus lateralis in the anterolateral thigh flap to give the bulkiness for restoring the tongue.

Alternatives are predominant muscular flaps with a cutaneous component such as musculocutaneous rectus abdominis or the latissimus dorsi flap.

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