This chapter presents a basic overview of the approach to reconstruction of cutaneous facial defects with local skin flaps. Emphasis is placed on the understanding of the anatomy, evaluation of a defect, and design of an appropriate local skin flap.
ESSENTIALS OF DIAGNOSIS
For successful local flap reconstruction of facial defects, the surgeon must have a thorough understanding of the following:
Biomechanics of soft tissues.
Vascular supply to the face and given skin flap.
Aesthetic subunits and the relaxed skin tension lines of the face.
Dimensions and depth of the defect.
Inherent structural characteristics of the native skin in the area of the defect (ie, thickness and sebaceous character).
Successful reconstruction of facial defects requires a thorough understanding of skin anatomy and physiology, careful analysis of the defect, and meticulous soft-tissue techniques. Options for reconstruction should generally proceed from least invasive to most invasive in terms of morbidity. This approach is termed the reconstructive ladder. Most facial defects that are too large for primary closure are amenable to local flaps. When planned and executed properly, local flaps allow for rapid reconstruction with a reliable blood supply, minimal morbidity, and excellent cosmesis. This chapter reviews the classification of commonly used local skin flaps and outlines the use of local flaps for facial reconstruction. In considering the appropriate surgical approach for a given defect, the surgeon should remember that secondary-intention healing is a viable option for concave areas of the face.
PRINCIPLES IN FLAP DESIGN
When possible, local flaps should be designed in the same aesthetic unit as the initial defect. Lines of excision should usually be made parallel to relaxed skin tension lines (RSTLs) or along aesthetic borders to optimize scar camouflage. If the defect involves multiple aesthetic subunits, it may be necessary to use a separate flap for each subunit. If more than 50% of a subunit is involved, the defect may be enlarged to reconstruct the entire unit with a flap. Placing incisions parallel to RSTLs reduces tension on wound closure by placing maximal tension into lines of maximal extensibility (LME). Skin tension and its distribution are important to avoid distortion of key facial landmarks such as the eyelid, lip, and the nasal ala.
FJ. The subunit principle in nasal reconstruction. Plast Reconstr Surg. 1985;76:329–347. (Classic article describing the subunits of the nose.)
JA. Secondary intention healing: an alternative to surgical repair. Clin Dermatol
. 1984;2:92–106. (This paper describes secondary-intention healing and the areas of the face that are most amenable to this technique.)
Local skin flaps can be classified either by their blood supply or by the method of transfer (Table 80–1).
Table 80–1Classification of local flaps by tissue movement.