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Contributors
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Matteo A. Angelini, MD
Plastic Surgeon
Private Practice
Rome, Italy
Marcelo Cunha Araujo, MD
Plastic Surgeon
Private Practice
Sao Paulo, Brazil
Esther Barrios, MD
Aesthetic and Reconstructive Plastic Surgeon
Private practice
Rio de Janeiro, Brazil
Justin Bellamy, MD
Plastic Surgeon
Private Practice
Palm Beach Gardens, Florida, USA
Ashley N. Boustany, MD
Instructor in Plastic Surgery
Division of Plastic Surger y
Beth Israel Deaconess Medical Center
Harvard Medical School
Boston, Massachusetts, USA
Christopher T. Chia, MD
Plastic Surgeon
Private Practice
New York, New York, USA
Enzo R. Citarella, MD
Plastic Surgeon
Department of Plastic Surgery
Pontifical Catholic University and Carlos
Chagas Institute
Rio de Janeiro, Brazil
Alexandra Condé-Green, MD, FICS
Plastic Surgeon
ACG Plastic Surgery
Boca Raton–Delray Beach, Florida, USA
Erez Dayan, MD
Plastic and Reconstructive Surgeon;
Medical Director
Avance Plastic Surgery Institute
Reno, Nevada, USA
Jeffrey S. Dover, MD, FRCPC
Dermatologist
Private Practice
SkinCare Physicians
Chestnut Hill, Massachusetts, USA;
Department of Dermatology
Yale University School of Medicine
New Haven, Connecticut, USA
Trina G. Ebersole, MD
Assistant Professor of Surgery
Plastic & Reconstructive Surgery
Washington University in St. Louis School of Medicine
St. Louis, Missouri, USA
Jose A. Foppiani, MD
Chairman LF1 Surgical Society
Plastic & Reconstructive Surgery Research Fellow
Beth Israel Deaconess Medical Center / Harvard
Medical School
Boston, Massachusetts, USA
Daniel J. Gould, MD, PhD
Plastic Surgeon
Gould Plastic Surgery, Marina Plastic Surgery, USC
Marina Del Rey, California, USA
Ritwik Grover, MD
Plastic Surgeon
The Plastic Surgery Center
Whitehall, Pennsylvania, USA
Jacob N. Grow, MD
Aesthetic Surgery Fellow
Department of Plastic Surgery
Cleveland Clinic
Cleveland, Ohio, USA
Rafael A. Couto, MD
Plastic and Reconstructive Surgeon
Couto Plastic Surgery – Private Practice
San Juan, Puerto Rico, USA
Samir Janne Hasbun, MD
Private Practice
Plastic and Reconstructive Surgeon
Puerto Colombia, Barranquilla, Colombia
xix
Contributors
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Sara R. Hogan, MD, FAAD
Health Sciences Clinical Instructor
Division of Dermatology
University of California Los Angeles
Los Angeles, California, USA
Dennis J. Hurwitz, MD
Plastic Surgeon
Clinical Professor of Plastic Surgery
University of Pittsburgh
Pittsburgh, Pennsylvania, USA
Michael S. Kaminer, MD
Private Practice
SkinCare Physicians
Chestnut Hill, Massachusetts, USA;
Department of Dermatology
Yale University School of Medicine
New Haven, Connecticut, USA
Andrew L. Kochuba, MD
Aesthetic Plastic Surgeon
Private Practice
Reston, Virginia, USA
Samuel J. Lin, MD, MBA, FACS
Program Director
BIDMC/HMS Plastic Surgery Residency
Training Programs;
Co-Director
Harvard Aesthetic and Reconstructive
Fellowship at BIDMC
Associate Professor of Surgery
Divisions of Plastic Surgery and Otolaryngology
Beth Israel Deaconess Medical Center
Harvard Medical School
Boston, Massachusetts, USA
Amer H. Nassar, MD PGY-9
Plastic and Reconstructive Surgery–BIDMC
Harvard Medical School
Boston, Massachusetts, USA
Mathew N. Nicholas, MD
Dermatology PGY-4
Division of Dermatology
University of Toronto
Toronto, Ontario, Canada
Jeremie O. Piña, MS
PhD Candidate
Department of Biomedical Engineering and
School of Dentistry
University of Utah
Sal Lake City, Utah, USA
Mario Pelle-Ceravolo, MD
Professor and Head of Plastic Surgery
University of Padua
Rome, Italy
Nelson A. Rodriguez-Unda, MD
Chief Resident in Plastic Surgery
Baylor Scott-White, Texas A&M College of Medicine
Temple, Texas, USA
Rod J. Rohrich, MD
Clinical Professor of Plastic Surgery
Baylor College of Medicine;
Past Chair/Distinguished Teaching Professor of
Plastic Surgery
UTSW;
Founding Partner
Dallas Plastic Surgery Institute
Dallas, Texas, USA
Munique Maia, MD
Plastic Surgeon
Private Practice
Tysons Corner, Virginia, USA
Alan Matarasso, MD, FACS
Plastic Surgeon
New York, New York, USA;
Clinical Professor of Surgery
Hofstra University, Northwell School of Medicine
New York, New York, USA
xx
Ramil Sinder, MD
Department of Plastic Surgery
Pontifical Catholic University of Rio de Janeiro
Rio de Janeiro, Brazil
Sumner A. Slavin, MD
Associate Clinical Professor of Surgery
Beth Israel Deaconess Medical Center
Harvard Medical School
Boston, Massachusetts, USA
Contributors
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Aris Sterodimas, MD, MSc, PhD, ARCS
Head
Plastic & Reconstructive Department
Department of Plastic Surgery
Metropolitan General Hospital
Athens, Greece
Benjamin Talei, MD
Facial Plastic Surgeon
Beverly Hills Center for Plastic Surgery
Beverly Hills, California, USA
Vickram J. Tandon, MD
Plastic Surgeon
Boston Center for Plastic Surgery
Boston, Massachusetts, USA
Hedyeh Ziai, MD
Facial Cosmetic and Reconstructive Surgery Fellow
Beverly Hills Center
Los Angeles, California, USA
James E. Zins, MD
Chairman
Plastic Surgery
Cleveland Clinic
Cleveland, Ohio, USA
xxi
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1 Neck Anatomy
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Jeremie O. Piña and Sumner A. Slavin
Abstract
Critically integrated with the facial aging process,
the neck and its supporting structures require targeted evaluation and treatment for successful neck
rejuvenation. A good understanding of the anatomy of the surgical site enables the operating surgeon to approach each individual patient with
confidence and caution. Herein, we present a brief
summary of the major surgically relevant anatomical structures pertinent to rejuvenation of the neck
and its supporting tissues.
Keywords: anatomy, fascia, platysma, SMAS, facial
nerve, retaining ligaments, lower lip
Key Points
●
Knowledge of neck anatomy empowers the
clinician to optimize patient-specific outcomes
in surgical and nonsurgical neck rejuvenation.
●
Maintaining the integrity of the key supporting
structures within the neck (e.g., superficial fascial
layer) helps curtail bleeding from cut muscle and
preserves the strength of the musculofascial layer
during neck dissection.
●
It is critical to know where to find the neurovascular structures most at risk during neck rejuvenation procedures, and to understand how to
effectively treat any related complications.
1.1 Cervical Triangles
Although clinicians typically approach the neck in
terms of aesthetic units, anatomists still refer to
the muscular triangles when describing both the
surfaces and contents of the neck. The sternocleidomastoid muscle divides the sides of the neck
into the anterior and posterior triangles.
The anterior triangle is bordered by the midline
and the mandible, further subdividing into the submandibular, carotid, and muscular triangles. The
carotid and muscular triangles are separated by the
posterior belly of the digastric muscle (accompanied by the stylohyoid muscle), and the region
splitting the anterior bellies of the digastric muscles
from the hyoid bone is referred to as the submental
1
triangle.
The posterior triangle is bounded by the trapezius, sternocleidomastoid, and middle third of the
clavicle. This triangle can be further subdivided as
well, into the supraclavicular (omoclavicular) and
posterior cervical (occipital) triangles, split by the
inferior belly of the omohyoid muscle.
2
1.2 Fasciae of the Neck
1.2.1 Superficial
As a discrete sheet of subcutaneous connective tissue, the superficial fascia encases the platysma
muscle (the only muscle in the head and neck without a direct bony origin or insertion) and fuses into
a single layer along the neck midline, forming a
midline bridge of superficial fascia so thin that in
most patients it is essentially invisible.
cutaneous lipectomy in the neck, maintaining the
integrity of this thin superficial fascial layer helps
curtail bleeding from cut muscle and preserves the
strength of the musculofascial layer.
The superficial fascia arises inferiorly from the
deep thoracic fascia, covering the pectoralis major
and deltoid muscles. At the lateral aspects of the
neck, the superficial fascia fuses with the investing
deep fascia covering the sternomastoid and trapezius muscles. Above the mandibular border, the
superficial fascia (then referred to as the superficial musculoaponeurotic system, or SMAS) and its
platysma component become increasingly fibrous.
While there is always a distinction between the
SMAS and deep fascia (also called the parotideomasseteric fascia or parotid capsule) at the lateral
aspect of the cheek, the pretragal region represents a region of closely attached fibers.
the parotid, however, the SMAS becomes thinner
and increasingly difficult to visualize (gross and
microscopically). It eventually becomes an invisible epimysium, enveloping the superficial layer of
the perioral and periorbital muscles (e.g., risorius,
zygomaticus major and minor, orbicularis oculi).
Further toward the facial midline, the SMAS may
continue across the nasolabial crease as the superficial portion of the orbicularis oris muscle.
Superior to the parotid gland, the SMAS and deep
fascia of the cheek coalesce approximately 1 cm caudal to its insertion into the zygomatic arch, signifying
3
During sub-
4
Lateral to
5
1
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that the SMAS is likely not contiguous with the
superficial fascia of the lateral orbital and temporal
regions of the scalp (this ma y be referred to as the
superficial temporalis fascia, the temporoparietal fascia, the galea aponeurotica, or th e fronto-occipitalis
6
layer).
Howev er, there remains some scrutiny in the
field regarding this anatomical convergenc e.
7
1.2.2 Deep
The deep fasciae of the neck are arranged somewhat
concentrically, running contiguous on the inferior
aspect with the deep thoracic fascia and on the
superior aspect with the cranial fasciae. The most
superficial layer of the deep fascia (and the most important in regard to neck lift surgery) is the in v esting
deep fascia (often confused with the real superficial
fascia of the neck, aka the platysma and SMAS).
7
This
superficial layer of the deep cervical fascia envelops
the deep neck tissues from anterior to posterior in a
continuous sleeve of connective tissue, similar to the
fasciae seen encompassed in the limb s.
Further division of the deep investing fascia encloses the sternomastoid and trapezius muscles
before reconverging into a single sheet covering the
anterior and posterior triangles of the neck. The
deep investing fascia maintains attachments to all
exposed bony parts and ligaments in its path, from
the occipital protuberance, ligamentum nuchae,
and spine of C7 posteriorly to the superior nuchal
line, mastoid process, and mandible cephalically.
8
splits above the mandible to encapsulate the parotid gland, and splits below the mandible to envelop
the submandibular salivary gland. A thickening of
this fascia extends from the tip of the styloid process
to the angle of the mandible (aka the stylomandibular ligament or interglandular septum), creating a
common wall between the capsules surrounding
the parotid and submandibular glands.
9
1.2.3 Infrahyoid Muscle Fascia
Classically referred to as the “middle fascia,” the fas-
cia of the infrahyoid muscles actually consists of two
distinct layers: the superficial layer (enclosing the
sternohyoid and omohy oid muscles) and the deep
layer (investing the sternothyroid and thyrohyoid
muscles).
10
1.2.4 Visceral Fascia
The visceral fascia is split into two components: the
pretracheal fascia (covering the larynx, trachea, and
thyroid gland) and the buccopharyngeal fascia (covering the buccinator muscle and dorsal esophagus).
1.2.5 Prevertebral Fascia
The prevertebral fascia envelops the vertebral column and its surrounding muscles as well as covering the prevertebral musculature, forming the
floor of the posterior triangle of the neck (aka the
“fascial carpet”).
1.2.6 Carotid Sheath
The carotid sheath envelops the internal and common carotid arteries, as well as the jugular vein
and the vagus nerve. The pretracheal (thyroid) fascia is adherent to it along with the investing deep
fascia under the sternomastoid muscle.
the lateral aspect of the sternomastoid muscle, the
nerves providing sensory input to the neck (e.g.,
great auricular nerve, lesser occipital nerve, transverse cervical nerve, and supraclavicular nerves)
pierce the investing deep fascia and thereafter become enclosed by the thin layer of superficial neck
12
fascia.
sternomastoid muscle, the spinal accessory nerve
emerges within the posterior triangle of the neck,
continuing downward and backward toward the
trapezius muscle under a thin two-layer veil of fascia (investing deep and superficial neck fasciae).
It
vesting deep fascia crosses the midline of the neck,
enveloping and attaching to the entire body and the
greater horn of the hyoid bone, finally inserting
above into the symphysis menti. The fascia of the anterior bellies of the digastric muscles and the fascia
of the mylohyoid muscles are also contained within
this investing deep fascia. Of particular importance
in neck lift surgery, the investing deep fascia often
needs to be vertically lengthened by partial transverse incisions or excisions to im pro v e the depth
and definition of the hy oid an gle.
paramedian areas, the investing deep fascia acts as a
visual and mechanical safe ty barrier, given that there
are no vital midline structures superficial to the investing deep fascia.
the midline of the neck between the infrahyoid strap
muscles, exis t thre e layers of fascia: the investing
deep fasci a, the fused strap muscle fascia, and the
pretracheal fascia. Clinically, all three of these fascial
layers appear as one blended matrix.
Further posterior along the edge of the
Anterior to the sternomastoid muscles, the in-
10
When operating on the subplatysmal midline and
4
Inferior to the h y oid bon e, along
13
11
Along
2
1.3 Platysma and Lower Lip
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1.3 Platysma and Lower Lip
Situated between the subcutaneous fat and the
subplatysmal fat (superficial and deep adipofascial
layers, respectively), the platysma muscle is a
broad elastic dual-sided band whose thickness and
width vary widely. Of important clinical significance, the platysma shares a physical and functional connectivity to the corners of the mouth
(aka the modiolus, a dense, flexible fibromuscular
mass palpable just lateral to the oral commissure),
which can lead to lower lip depressor weakness
following neck lift or face lift surgery.
the depressor anguli oris is a muscle that inserts
into the modiolus just outside the corner of the
mouth, with just a few f ibers extended directly into the lateral lower lip. Immediately adjacent sits
the labial part of the platysma (aka the pars labialis
platysma) running beneath the depressor anguli
oris and inserting into the lateral lower lip. Alongside in the same plane to the labial part of the platysma (and even intermingling fibers along the
way) runs the depressor labii inferioris muscle.
The orbicularis oris serves as the lower lip tight-
ener, blending with a network of perioral muscles
with its embryologically distinct parts: pars mar-
ginalis (superficial, beneath the vermillion, blends
with the SMAS) and the pars peripheralis (deep,
caudal nonvermillion portion of the lip, derived
from the buccinator muscle).
2
The orbicularis oris
receives its innervation from the lower buccal
branches and mandibular branches of the facial
nerve.
An accessory part of the orbicularis oris muscle
is the incisivus labii inferioris, having bony attachment to the floor of the incisive fossa of the
mandible lateral to the mentalis muscle.
muscle’s action is to pull the corner of the mouth
toward the midline, as is done when pursing the
lips for whistling.
Interlacing its fibers with this network of lower
lip muscles, the platysma can be envisioned as
being composed of three parts. The predominant
pars modiolaris platysma sits posterolateral to
the depressor anguli oris, pulling the corner of the
mouth outward and downward. The intermediate
pars labialis platysma runs deep to the depressor
anguli oris, occupying the space between the depressor anguli oris and the depressor labii inferioris. The anterior pars mandibularis platysma finds
its attachment at the center of the mandible and
14
Namely,
15
15
This
crosses the mental protuberance, extending vertically to the lower lip.
The risorius, considered the corner of the
mouth stretcher, pulls the corner laterally via its
transverse orientation toward the cheek, arising
from the parotideomasseteric fascia and inserting
into the modiolus. Innervated by the buccal branch
of the facial nerve, the risorius may share fibers
and functionality with the upper oblique fibers of
the pars modiolaris of the platysma.
16
In some pa-
tients, the risorius is absent.
The depressor anguli or is is a prominent and
superficial muscle taking origin from the oblique
line of the mandible. Its fibers pass upward to converge on the modiolus, with some fibers of the
pars modiolaris platysma blending with those of
the depressor anguli oris. This muscle is not a true
depressor of the lower lip; instead, it is a depressor
of the corner of the mouth (modiolus), often working in concert with the mentalis muscle.
17
Buccal
and mandibular branches of the facial nerve provide its innervation.
The depressor labii inferioris arises from the
mandible above the oblique line medial to the
mental foramen, with fibers directed upward and
medially before inserting into the skin of the lower
lip. Inferolaterally it is continuous with the pars
labialis of the platysma. The depressor labii inferioris
pulls the lower lip downward and in a slightly lateral
direction, potentially e xposin g the lower teeth down
to the gingiva.
18
Its action may also cause the chin to
wrinkle slightly. Its motor nerve is a marginal mandibular branch, and it functions primarily during
phonation.
The mentalis is a dual-sided (one on each side
of the midline), small conical muscle arising from
the mandible below the incisors.
19
The mentalis
fans out into the skin of the chin just inferior to
the pars marginalis of the orbicularis oris muscle.
Its action pulls the skin of the lower chin upward,
puckering it, and thus assists in protruding the
lower lip.
20
It is innervated by one of the marginal
mandibular branches of the facial nerve.
The depressor labii inferioris, likely in tandem
with the pars labialis platysma, contributes to pulling the lower lip downward so the lower teeth are
bared sometimes almost to the gingiva while simultaneously pulling the lip slightly outward away
from the teeth, creating a shadowed overhang.
However, both muscles likely pull the lower lip
downward in the so-called full-denture smile, in
21
3
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which the lower teeth are unveiled, creating a
square-shaped mouth.
The depressor anguli oris muscle fibers sit uate
around the chin like a chin strap, but they do not
directly insert into the lower lip.
each muscle is to pull the corner of mouth downward, producing a signature row of curved transverse bulges, similar to waves approaching a
shoreline. This muscle also creates a frown that
looks like an upside-down smile. The depressor
anguli oris muscles often act in tandem with the
mentalis muscles to create an expression sometimes called the “facial shrug.”
22
The action of
1.4 Critical Structures
Surrounding Neck Muscles
The region of the neck between the posterior border of the platysma and the anterior border of the
trapezius muscle is an anatomically congested
neighborhood. Within these boundaries are identified the main sensory nerves of the upper neck
and periauricular region, the external jugular vein,
and just enough of the spinal accessory nerve to
cause that nerve to be occasionally vulnerable during surgery. According to Feldman, during neck lift
surgery, this is an area that very often needs skin
flap undermining to obtain an adequate redistribution of the lateral neck skin, but it is also the area
that is the most difficult to undermine, given the
network of tight connective tissue binding the skin
to the investing deep fascia covering the sternomastoid and trapezius muscles.
to know where to find the neurovascular structures most at risk during neck rejuvenation procedures (▶ Fig. 1.1).
10
Thus, it is critical
1.4.1 External Jugular Vein
Formed just beneath the superficial fascia, posterior
and inferior to the angle of the mandible, the exter-
nal jugular vein arises from a union of the retromandibular vein and the posterior auricular vein.
This union can sometimes occur at the caudal edge
of the parotid gland.
the superficial fascia of the neck, the external jugular vein obliquely crosses over the sternomastoid
muscle near the junction of the lower and middle
thirds of the muscle belly, with a trajectory toward
the midclavicle. Just above the clavicle (~2 cm), it
pierces the investing deep fascia, coalescing as
the subclavian vein. As the posterior border of the
23
Descending vertically beneath
platysma muscle often runs parallel and anterior
to the external jugular vein, the vein may not be
underneath the muscle along a good portion of its
course; rather, it may instead just be covered by a
thin veil of superficial cervical fascia.
1.4.2 Other Superficial Veins
Right and left anterior jugular veins, unequal in
size and placement, emerge in the submental region, running just off the midline within the subplatysmal fat overlying the investing deep fascia
and sternohyoid muscles to eventually pierce the
deep fascia approximately 1 inch above the manubrium to enter the substernal space and unite.
They also course laterally along the upper border
of the clavicles between the sternomastoid and
infrahyoid strap muscles, ending in the external
jugular vein. Sometimes, a communicating vein,
lying along the anterior border of the sternomastoid muscle, connects the common facial vein and
the anterior jugular veins.
25
1.5 Sensory Distribution in the
Neck
1.5.1 Great Auricular Nerve
With very little (if any) dispute, the statement
made by Rees and Aston in 1978 remains the consensus: The nerve most frequently injured during
face and neck lift surgery is a sensory nerve, the
great auricular nerve, the largest branch of the
cervical sensory plexus.
innervation to the lower half to two-th irds of the
ear as well as the inferior preauricular area and a
variable postauricular area covering the mastoid.
The great auricular nerve emerges approximately
midway along the posterior border of the sternomastoid muscle, looping onto the surface of the
muscle where it heads straight upward approaching the angle of t he mandible. The main ner ve
2
body runs vertically upward and c an variably be
identified just beneath or just superf icial to the
sternomastoid fascia as it courses up to the base
of the ear lobule. Thus, when elevating a skin flap
in the lateral neck, m aintaining the integrity of
the sternomastoid fascia will greatly increase the
likelihood of preserving the great auricular nerve.
However, given the variability in the nerve’s
course along the sternomastoid fascia, this is not
always the case.
27
26,49
It supplies sensory
Within 1 to 2 cm of the ear
24
4
1.5 Sensory Distribution in the Neck
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Fig. 1.1 (a., artery; v., vein; n., nerve; m., muscle) Critical anatomical structures in the neck and lower face. Courtesy
Wasila Madhoun, MD.
lobule, the great auricular nerve arborizes within
the deep fibrofatty subcutaneous tissues, spreading anterior f ibers into the parotid gland. Spanning from an injury to one of the small distal
branches of the nerve near the e ar lobule to an injury of the m ain nerve body overlying the sternomastoid muscle, a spectrum of dysesthesias can
range from mild, temporary, small areas of hypesthesia to a longer- lasting, dense, numbness of the
entire lower ear, or even to a painful neuroma at a
site of more proximal partial or complete nerve
transection.
of transient numbness around the ear following
face and neck lift surgery, many surgeons consider
this to be a normal consequence of the operation,
not a complication.
28
Given the relatively high incidence
10
1.5.2 Lesser Occipital Nerve
Providing sensory innervation for most of the postauricular mastoid region, as well as sensation to the
upper ear, the lesser occipital nerve emerges
behind the posterior edge of the sternomastoid
muscle cephalad to the great auricular nerve at a
point approximately 5.3 cm below a transverse line
connecting the lowest points of the external auditory canals and 6.5 cm from the vertical posterior
29
midline.
sternomastoid fascia and the platysma–SMAS layer,
it provides terminal branches to the ear and mastoid
areas. Similar to the great auricular nerve, the lesser
occipital nerve begins deep to the superficial fascia
(platysma–SMAS layer), but often becomes more
Traveling obliquely upward between the
5
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superficial (i.e., more proximal and caudal) earlier
than does the great auricular nerve. In order to
maintain adequate blood supply to the postauricular
skin flap during neck lift or face lift surgery, it is
common for surgeons to elevate the mastoid area
skin flap just superficial to the sternomastoid fascia;
however, dissection on the muscle fascia may lead
to injuring of some of the major terminal branches
of the lesser occipital nerve, which run more superficial in the subcutaneous tissue in this region.
Thus, it is suggested to leave behind a little fatty tissue on the muscle fascia.
1.5.3 Spinal Accessory Nerve
Fortunately, it is uncommon for the spinal accessory nerve to be found in the field of dissection
during the majority of neck lift surgeries. However,
some patients will require a far-lateral neck skin
undermining, which places this nerve close at
10
hand.
Similar to the great auricular nerve, the
spinal accessory nerve is often found sandwiched
tightly between the skin and muscle fascia; as
such, when attempting to free up the skin in the
lower lateral neck, it is possible that the spinal
accessory nerve emerges and could be injured. In
such a case, a spectrum of symptoms can arise depending on the extent and severity of nerve injury;
neurapraxia can cause temporary pain in the
shoulder and trapezius muscle dysfunction even
when the nerve is entirely intact, whereas in a severe injury (e.g., partial or complete transection) a
progressive and debilitating dysfunction of the entire girdle could result. Very close attention must be
paid intraoperatively to determine the extent of
possible nerve injury, and if any postoperative clinical signs or symptoms of trapezius dysfunction are
identified, operative repair of the transected nerve
should be performed within 3 months of the original surgery for optimal recovery of function.
1.6 Retaining Ligaments of the
Face and Neck
Retaining ligaments are strong, discrete aggregations of fibrous connective tissue holding hard and
soft tissues to one another at specific attachment
31
sites.
There are five general categories of retaining ligaments, namely, aptly according to their
deep to superficial attachments: periosteum to
skin (osteocutaneous), periosteum to deep fascia
and or superficial fascia (osteofascial), deep fascia
to superficial fascia (fascio-fascial), and deep fascia
and/or superficial fascia to skin (fasciocutaneous).
Furthermore, retaining filaments are rows of specialized fasciocutaneous fibers within the subcutaneous fat, serving as more densely packed, tighter
anchors to bond the skin and the superficial fascia
at specified areas in the neck.
32
Specifically anchoring the neck skin in position,
30
there are nine identifiable retaining ligaments and
filaments: the mandibular ligaments, the submental ligaments, the mastoid-cutaneous ligaments, the
platysma-auricular ligaments (including earlobe
ligaments), the lateral sternomastoid-cutaneous ligaments, the clavicular-cutaneous ligaments, the
medial platysma-cutaneous filaments, the medial
sternomastoid-cutaneous filaments, and the skin
crease-platysma filaments.
10
In addition, there are
three identifiable retaining ligaments anchoring the
platysma muscle to deeper underlying tissues: the
hyoid ligament, the paramedian platysma retaining
ligaments, and the submandibular platysma retaining ligaments.
33
Found on either side of the chin, the mandibular
ligaments emerge from their osseous origin between fibers of the pars labialis of the platysma and
the lateral border of the depressor anguli oris
muscle, approximate ly 1cm superior to the mandibular border, running outward to a solid insertion in
the overlying dermis.
34
These ligaments outline the
anterior border of the jowl, primarily responsible for
the indentation that is often seen in this region
called the prejowl notch. Surgical division of the
mandibular ligaments just under the skin (superficial to the SMAS–platysmalayer),inadditiontoa
repositioning or trimming of the ptotic jowl fat, typically elimina te s the prejowl notch.
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A true lift of the soft tissues in the face and/or
neck involves lateral skin excision coupled with severing the mandibular ligaments and releasing
the tissues along the medial jawline so that they
can be stretched back into a smoother contour.
As the mandibular ligaments are short and strong,
they cannot be divided simply by passing through
open scissor tips; it is necessary to cut sharply by
snipping just beneath the skin. Of importance, the
marginal branches of the facial nerve are deep to
the SMAS–platysma layer, so scissoring superficial
to both the depressor anguli oris and platysma
muscles can be done without risking nerve injury.
The labiomandibular crease, or marionette
crease, runs from the modiolus to the mandible.
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