68.1 Introduction

Static procedures, once the mainstay of rehabilitation of the paralyzed face, have been relegated to the back seat in the era of dynamic gracilis free flaps and nerve transfer. Despite the measurable benefit of dynamic procedures, static procedures represent a critical and often central element in the rehabilitation of the paralyzed face. Static procedures can be used in patients who are not candidates for dynamic reconstruction, whether they are unfit for more involved surgical procedures, the lack of adequate patient resources for dynamic reconstruction, or the experience of the surgeon. They can also be used as adjuncts to dynamic procedures, particularly dynamic temporalis procedures or gracilis free flaps, which provide a unidirectional vector of excursion, and do not address the complex features of facial expression. Finally, they can provide resting symmetry and immediate functional benefit during the lengthy process of recovery and regeneration from procedures requiring neural regeneration and retraining.

The primary goals of facial reanimation are three-fold: (1) to restore facial symmetry, (2) to replace deficient facial volume due to atrophy and loss of static suspension of facial structures, and (3) most importantly to restore facial function necessary for vision, globe protection, nasal breathing, and oral function for competence and articulation. Management of the eye after facial paralysis is discussed in Chapter 63, gracilis free muscle transfer in Chapter 67, and nerve substitution techniques in Chapters 65 and 66. The focus of this chapter will be procedures designed to restore form and function to the mid and lower face.

68.2 Anatomy

The nasalis muscle is the most developed of the nasal muscles (Fig. 68‑1 ). It consists of the compressor naris (transverse) and dilator naris (alar). The compressor naris runs vertically from the canine eminence to pair with the same muscle of the contralateral side and extends to an aponeurosis of the procerus muscle. The paired contraction results in the depression of the cartilaginous portion of the nose and contraction of the ala toward the septum. The dilator naris muscle originates in the subnasal fossa and inserts in the cartilaginous ala of the nose. The nasal slip of the levator labii superioris alaeque nasi serves as a dilator of the nares, originating on the frontal process of the maxilla. In flaccid facial paralysis, nasal asymmetry and functional collapse also occur secondary to the absence of tone and the effects of gravity resulting in medial and inferior displacement of the alar base. Notably no muscles insert directly into the alar base with an oblique lateral trajectory, and maneuvers to correct this portion of facial deformity should be tailored with this in mind.s. Literatur

Progressing clockwise around the mouth are the five upper lip elevators (levator labii superioris alaeque nasi, levator labii superioris, zygomaticus minor, levator anguli oris, and zygomaticus major); the risorius, which laterally retracts the commissure; three depressors (platysma, depressor anguli oris, and depressor labii inferioris); and the mentalis muscle, which elevates the lower lip (Fig. 68‑2 ). The orbicularis oris muscle forms a circumferential sphincter around the mouth. The two levator labii muscles act primarily to elevate and evert the upper lip. The levator anguli oris originates on the canine fossa of the maxilla just below the infraorbital foramen, deepening the nasolabial fold. The zygomaticus major originates on the medial zygoma and inserts into the skin and mucosa of the corner of the mouth as part of the modiolus, drawing it upward and laterally, and with the levator anguli oris, raises the angle of the mouth to form the nasolabial fold. The zygomaticus minor muscle originates just medial to the major muscle, and is not part of the modiolus, and elevates and everts the lip.s. Literatur

The depressor anguli oris and depressor labii inferioris depress the angle of the mouth and lower lip, respectively, along with the platysma muscle. The mentalis muscle has the paradoxical function of raising and everting the lower lip, as well as elevating the skin of the chin.s. Literatur

68.3 Materials

A wide variety of tissues and materials have been described for static facial slings, including autologous fascia lata or palmaris longus tendon, cadaveric fascia lata, suture suspension, acellular dermis products, expanded polytetrafluoroethylene (Gore-Tex), crystalline polypropylene and high-density polyethylene (Marlex), and silicone rods. Each option has its advantages and disadvantages. The issue of relaxation or stretching is frequently cited as an advantage of one material over another over time, though it would appear that this issue exists for all materials, and no side-by-side comparisons have clearly demonstrated one to be superior over another with regard to this aspect.s. Literatur ^,​ s. Literatur

The palmaris longus tendon is a small tendon arising from the medial epicondyle of the humerus and inserts on the flexor retinaculum, and is variably absent in approximately 14% of the population.s. Literatur

Autologous tendon has the distinct advantage of lower risk of infection, rejection, or reaction. Tensor fascia lata (TFL) can be easily harvested in sufficient quantity from one side to provide for several reconstructive needs. The incisions can be minimized to limit deformity at the donor site.s. Literatur It has the disadvantage of the time for harvest and the donor site is frequently complicated by seroma formation. In a radiated field, TFL or palmaris longus tendon should be used. The TFL originates from the lateral surface of the lateral iliac crest and inserts on the condyle of the tibia. It serves as a minor hip flexor and abductor.s. Literatur

Acellular dermis has the advantage of being readily available with no donor-site morbidity. It is less likely to result in infection, but still carries the risk of local reaction or infection.s. Literatur A weakness but potential utility of acellular dermis is that it will frequently reabsorb, and can therefore be used for temporary suspension when neural recover is anticipated.s. Literatur

Gore-Tex and Marlex also share the advantage of being off-the-shelf products with no associated donor-site morbidity. Gore-Tex has been noted to relax significantly over time, and carries a risk of infection, granulation formation, and extrusion, and should be avoided in patients with poor wound healing potential or in radiated tissue.s. Literatur

68.4 Goals of Static Reconstruction

The goals for static mid and lower face reconstruction are to: (1) restore nasal external valve dimensions, alar height, and lateral position; (2) restore the nasolabial fold, philtral position, and oral commissure symmetry and oral competence; (3) provide lower lip bulk and symmetric position; (4) and improve symmetric facial tone with rhytidectomy.