Face and scalp
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4
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Fig. 30.1 The distribution of relaxed skin
A B
tension lines (Kraissl’s lines). A, Lateral view.
B, Anterior view.
In the upper lip, a narrow band of smooth tissue related to the occipital artery can support hairbearing flaps from the scalp, which are
subnasal maxillae marks the point at which labial mucosa becomes useful for reconstructing defects involving the scalp. The nasolabial flap
continuous with gingival mucosa. The corresponding reflexion in the utilizes the lax skin just lateral to the nasolabial groove. It is not sup
lower lip coincides approximately with the mentolabial sulcus, and here plied by a named axial artery but rather its blood supply is provided by
the lip is continuous with mental tissues. The upper and lower lips many small branches from the underlying facial artery. These branches
differ in crosssectional profile in that neither is a simple fold of uniform run perpendicular to the skin surface. Nasolabial flaps can be either
thickness. The upper lip has a bulbous asymmetrical profile: the skin superiorly or inferiorly based.
and redlip have a slight external convexity, and the adjoining redlip
and mucosa a pronounced internal convexity, creating a mucosal ridge
or shelf that can be wrapped around the incisal edges of the parted SOFT TISSUE
teeth. The lower lip is on a more posterior plane than the upper lip. In
the position of neutral lip contact, the external surface of the lower lip FASCIAL LAYERS
is concave and there is little or no elevation of the internal mucosal
surface. The profile of the lips can be modified by muscular activity. Fascia of scalp
RELAXED SKIN TENSION LINES AND SKIN FLAPS The superficial fascia of the scalp is firm, dense and fibroadipose, and
adheres closely to both skin and the underlying epicranius and its
ON THE FACE
aponeurosis. Posteriorly, it is continuous with the superficial fascia of
the back of the neck; laterally, it is prolonged into the temporal region,
The direction in which facial skin tension is greatest varies regionally.
where it is looser in texture.
Skin tension lines, which follow the furrows formed when the skin is


relaxed, are known as ‘relaxed skin tension lines’ (Borges and Alexander
Fascial layers and tissue planes in the face
1962). In the living face, these lines frequently (but not always) coin
cide with wrinkle lines (Fig. 30.1) and can therefore act as a guide in
planning elective incisions. On the basis of gross dissection and complementary histological
When lesions on the face, such as scars, pigmented lesions and skin studies, four distinct tissue planes are recognized on the face superficial
cancers, are excised, the dimensions of these lesions often require exci to the plane of the facial nerve and its branches. From superficial to
sion as an ellipse, so that the resulting defect can be closed as a straight deep, these layers are the skin; a subcutaneous layer of fibroadipose
line. If the resulting scar is to be aesthetically acceptable, it is important tissue; the superficial musculoaponeurotic system (SMAS); and the
to make the long axis of the ellipse parallel to the natural relaxed skin parotid–masseteric fascia.
tension lines, so that the scar will look like a natural skin crease. If the
Subcutaneous fibroadipose tissue
excision line runs contrary to the skin tension lines, the scar may be
more conspicuous and will tend to stretch transversely as a result of This homogeneous layer is present throughout the face, although the
natural expressive facial movements. degree of adiposity varies in different parts of the face and with age.
When larger lesions are excised, it may be necessary to advance or Anteriorly, it crosses the nasolabial fold on to the lip; superiorly, it
rotate adjacent soft tissue to fill the defect. The ability to raise these skin crosses the zygomatic arch. In both locations, the layer is more fascial
flaps is entirely dependent on the regional blood supply, and both than fatty. The fat content of the subcutaneous tissue in the cheek
random pattern and axial pattern skin flaps are used surgically. Because accounts for the cheek mass; part of the subcutaneous adipose tissue is
of the richness of the subdermal plexus in the face, random pattern flaps the malar fat pad, a more or less discrete aggregation of fatty tissue


can be raised with a greater length:breadth ratio than in any other area inferolateral to the orbital margin.
of the body.
Superficial musculo-aponeurotic
The following are examples of axial pattern flaps that can be used to
system (SMAS)
reconstruct defects on the face and scalp. Supratrochlear/supraorbital
arteries support forehead flaps that are useful for nasal reconstruction; This is described as a single tissue plane in the face. In some areas, it is
there is usually enough skin laxity to allow the majority of the donor composed of muscle fibres, and elsewhere it is composed of fibrous or
site to be closed directly. The frontal branch of the superficial temporal fibroaponeurotic tissue; it is not directly attached to bone. When traced
artery anastomoses in the midline with its opposite number, and con below the level of the lower border of the mandible, it becomes con
sequently the entire forehead skin can be raised on a narrow pedicle tinuous with platysma in the neck. Microdissection has revealed that
based on just one of the superficial temporal arteries. These flaps can the superficial musculoaponeurotic system becomes indistinct on the
be used to repair many facial defects and also intraoral defects, but the lateral aspect of the face approximately 1 cm below the level of the
donor site defect cannot be closed directly and must be covered by a zygomatic arch. Anteromedially, the superficial musculoaponeurotic
skin graft. The parietal branch of the superficial temporal artery and the system layer becomes continuous with some of the mimetic muscles,


Bones of the facial skeleton and cranial vault
477
03
ReTpaHc
including zygomaticus major, frontalis and the periorbital fibres of temporal fascia is a dense aponeurotic layer that lies deep to the tem
orbicularis oculi (Yousif and Mendelson 1995). poroparietal fat pad and covers temporalis; the deep surface of the
In most areas of the face, a distinct subsuperficial musculo fascia affords attachment to the superficial fibres of temporalis. Above,
aponeurotic system plane can be defined deep to the superficial it is a single layer attached along the length of the superior temporal
musculoaponeurotic system. It is continuous with the plane between line, blending with the periosteum. Below, at approximately the level
platysma and the underlying investing layer of deep cervical fascia in of the superior orbital rim, it splits into superficial and deep laminae
the neck. However, where it overlies the parotid gland, the superficial that run downwards to attach to the lateral and medial margins of the
musculoaponeurotic system is firmly blended with the superficial layer upper surface of the zygomatic arch, respectively. These fascial attach
of the parotid fascia, which means that a clear subsuperficial musculo ments have a clinical application in the reduction of fractures of the
aponeurotic system plane is difficult, if not impossible, to define in the zygomatic complex via a Gillies approach: an instrument is inserted
region of the parotid. deep to the deep lamina of temporalis fascia through a scalp incision
and used to elevate depressed zygomatic complex fractures. The fat
Parotid–masseteric fascia enclosed between these two layers is termed the superficial temporal fat
This is a thin, translucent and tough fascial layer that covers the parotid pad; it contains the zygomaticoorbital branch of the superficial tem
duct and the buccal branch of the facial nerve and interconnecting poral artery and a cutaneous nerve, the zygomaticotemporal branch of
branches from the mandibular nerve as these structures all lie on the the maxillary nerve. The temporal fascia is overlapped by auriculares


surface of masseter. Further anteriorly, the parotid–masseteric fascia anterior and superior, the epicranial aponeurosis and part of orbicularis
overlies the buccal fat pad lying superficial to buccinator. Having oculi, and the superficial temporal vessels and auriculotemporal nerve
crossed the surface of the buccal fat pad, the fascia blends with the ascend over it.
epimysium on the surface of buccinator. It is continuous with the
Buccopharyngeal fascia
investing layer of deep cervical fascia below the lower border of
the mandible. Buccinator is covered by a thin layer of fascia, the buccopharyngeal
fascia, which also covers the superior constrictor of the pharynx
Parotid fascia (capsule) (Ch. 34).
The parotid gland is surrounded by a fibrous capsule called the parotid
Retaining ligaments of the face
fascia or capsule. Traditionally, this has been described as an upward
continuation of the investing layer of deep cervical fascia in the neck, These ligaments are fascial bands at specific sites, which serve to anchor
which splits to enclose the gland within a superficial and a deep layer. the skin to the underlying bone. The general cutaneous laxity that
The superficial layer is attached above to the zygomatic process of the attends the ageing process (Commentary 4.3) renders facial skin subject
temporal bone, the cartilaginous part of the external acoustic meatus, to gravitational pull. However, at sites where retaining ligaments are
and the mastoid process. The deep layer is attached to the mandible, present, the effect of gravitational pull is resisted. When performing
and to the tympanic plate, styloid and mastoid processes of the tempo facelift procedures, these ligaments must be surgically divided in order
ral bone. The prevailing view is that the deep layer of the parotid capsule to facilitate redraping of facial skin. Examples of retaining ligaments in
is derived from the deep cervical fascia. However, the superficial layer the face are the zygomatic ligament (also known as McGregor’s patch)
of the parotid capsule appears to be continuous with the fascia associ and the mandibular ligament.
ated with platysma, and is now regarded as a component of the super
Fascial spaces


ficial musculoaponeurotic system (Mitz and Peyronie 1976, Wassef
1987, Gosain et al 1993). It varies in thickness from a thick fibrous layer Two tissue spaces on the face may be involved in the spread of odon
anteriorly to a thin translucent membrane posteriorly. It may be traced togenic infection. They are the buccal tissue space, lying between the
forwards as a separate layer which passes over the masseteric fascia skin and the surface of buccinator, and the infraorbital tissue space,
(itself derived from the deep cervical fascia), separated from it by a cel lying between the bony attachments of levator labii superioris and
lular layer that contains branches of the facial nerve and the parotid levator anguli oris.
duct. Histologically, the parotid fascia is atypical in that it contains
muscle fibres that parallel those of platysma, especially in the lower part BONES OF THE FACIAL SKELETON AND
of the parotid capsule. Although thin fibrous septa may be seen in the
CRANIAL VAULT
subcutaneous layer at the histological level, macroscopically there is
little evidence of a distinct layer of superficial fascia.
The deep fascia covering the muscles forming the parotid bed (digas The facial skeleton is the anterior part of the skull and includes
tric and styloid group of muscles) contains the stylomandibular and the mandible. The bones of the nasoethmoidal and zygomaticomaxil
mandibulostylohyoid ligaments. The stylomandibular ligament passes lary complexes are described here. The mandible is described in
from the styloid process to the angle of the mandible. The more exten Chapter 32.
sive mandibulostylohyoid ligament (angular tract) passes between the
angle of the mandible and the stylohyoid ligament for varying dis
PARIETAL BONE
tances, generally reaching the hyoid bone. It is thick posteriorly but
thins anteriorly in the region of the angle of the mandible. There is
some dispute as to whether the mandibulostylohyoid ligament is part The two parietal bones form most of the cranial roof and sides of the


of the deep cervical fascia (Ziarah and Atkinson 1981) or lies deep to skull. Each is irregularly quadrilateral and has two surfaces, four borders
it (Shimada and Gasser 1988). The stylomandibular and mandibulo and four angles (Fig. 30.2).
stylohyoid ligaments separate the parotid gland region from the super The external surface is convex and smooth, with a central parietal
ficial part of the submandibular gland, and so are landmarks of surgical tuber (tuberosity). Curved superior and inferior temporal lines cross it
interest. and form posterosuperior arches. The temporal fascia is attached to the
superior line or arch, and temporalis is attached to the inferior line or
Temporoparietal and temporal fasciae
arch. The epicranial aponeurosis lies above these lines, and part of the
Above the level of the zygomatic arch, on the lateral side of the head, temporal fossa lies below. Posteriorly, close to the sagittal (superior)
the temporoparietal fascia (superficial temporal fascia) constitutes a border, an inconstant parietal foramen transmits a vein from the su
fascial layer that lies in the same plane as, but is not continuous with, perior sagittal sinus and sometimes a branch of the occipital artery.
the superficial musculoaponeurotic system. It is quite separate from, The internal surface is concave and marked by impressions of cere
and superficial to, the temporal fascia (deep temporal fascia). More bral gyri and by grooves for the middle meningeal vessels. The latter
superiorly, it blends with the galea aponeurotica. The plane between ascend, inclining backwards, from the sphenoidal (anteroinferior)
the temporoparietal fascia and the underlying deep temporal fascia angle and posterior half (or more) of its inferior border. A groove for
contains loose areolar tissue and a small amount of fat. This tissue the superior sagittal sinus lies along the sagittal border and is completed
plane, the temporoparietal fat pad, is continuous superiorly with the by the groove on the opposite parietal bone. The falx cerebri is attached


subgaleal plane of loose areolar tissue in the scalp. Running superiorly to the edges of the groove. Granular foveolae for arachnoid granulations
in the temporoparietal fascia or just deep to it are the superficial tem flank the sagittal sulcus and are most pronounced in old age.
poral vessels, the auriculotemporal nerve and its branches, and the The dentated sagittal border, longest and thickest, articulates with
temporal branches of the facial nerve. When raising a bicoronal flap, the opposite parietal bone at the sagittal suture. The anterior part of the
identification of the temporoparietal fat pad helps to separate these two squamosal (inferior) border is short, thin and truncated, bevelled exter
fascial layers; subsequent dissection in a plane deep to the temporo nally and overlapped by the greater wing of the sphenoid. The middle
parietal fascia protects the temporal branch of the facial nerve. The part of the inferior border is arched, bevelled externally and overlapped


Face and scalp
478
4
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A
Parietal foramen on sagittal margin
(for sagittal suture)
Frontal (anterosuperior) angle
Occipital (posterosuperior) angle
Parietal tuberosity
Superior temporal line
Occipital margin (for lambdoid suture)
Inferior temporal line
Frontal margin (for coronal suture)
Mastoid (posteroinferior) angle
Sphenoidal (anteroinferior) angle
Squamous margin (for squamosal suture)
B
Parietal foramen
Groove for superior sagittal sinus
Groove for middle meningeal vessels
Groove for sigmoid sinus
Fig. 30.2 The left parietal bone. A, External view. B, Internal view.
by the squamous part of the temporal bone. The posterior part of the subsequently radiates from them towards the margins. The angles are
inferior border is short, thick and serrated for articulation with the therefore the last parts to be ossified, and fontanelles occur at these
mastoid part. sites. At birth, the temporal lines are low down; they only reach their
The frontal border is deeply serrated, bevelled externally above and final position after the eruption of the molar teeth. Occasionally, the
internally below, and articulates with the frontal bone to form one half parietal bone is divided by an anteroposterior suture.
of the coronal suture. The occipital border, deeply dentated, articulates
with the occipital bone, forming one half of the lambdoid suture.
The frontal (anterosuperior) angle, which is approximately 90°, is FRONTAL BONE
at the bregma, where sagittal and coronal sutures meet, and marks the
site of the anterior fontanelle in the neonatal skull. The sphenoidal The frontal bone is like half of a shallow, irregular cap forming the
(anteroinferior) angle lies between the frontal bone and greater wing forehead or frons (Fig. 30.3). It has three parts and contains two cavi
of the sphenoid. Its internal surface is marked by a deep groove or canal ties, the frontal sinuses.
that carries the frontal branches of the middle meningeal vessels. The


frontal, parietal, sphenoid and temporal bones usually meet at the Squamous part
pterion, which marks the site of the sphenoidal fontanelle in the embry
onic skull. The frontal bone sometimes meets the squamous part of the
The squamous part forms the major portion of the frontal bone. Its
temporal bone, in which case the parietal bone fails to reach the greater
external surface has a rounded frontal tuber (tuberosity) approximately
wing of the sphenoid bone. The rounded occipital (posterosuperior)
3 cm above the midpoint of each supraorbital margin. These tubera
angle is at the lambda, the meeting of the sagittal and lambdoid sutures,
vary, but are especially prominent in young skulls and more so in adult
which marks the site of the posterior fontanelle in the neonatal skull.
females than males. Below them, and separated by a shallow groove,
The blunt mastoid (posteroinferior) angle articulates with the occipital
are two curved superciliary arches, medially prominent and joined by
bone and the mastoid portion of the temporal bones at the asterion.
a smooth median elevated glabella. The arches are more prominent in
Internally, it bears a broad, shallow groove for the junction of the
males; prominence depends partly on the size of the frontal sinuses,
transverse and sigmoid sinuses.
but is occasionally associated with small sinuses. The curved supra
orbital margins of the orbital openings lie inferior to the superciliary
Ossification
arches. The lateral twothirds of each margin are sharp, the medial third
rounded; a supraorbital notch or foramen, which transmits the supra
Each parietal bone is ossified from two centres that appear in dense orbital vessels and nerve, lies at the junction between them. A small
mesenchyme near the tuberosity, one above the other, at about the frontal notch or foramen lies medial to the supraorbital notch in half
seventh week in utero. These two centres unite early and ossification of skulls. Both features show sexual dimorphism. The supraorbital


Bones of the facial skeleton and cranial vault
479
03
ReTpaHc
A
Frontal eminence
Squamous part, external surface
Parietal margin
Superciliary arch
Supraorbital notch Temporal surface
Supraorbital margin
Zygomatic process
Orbital part, orbital surface
Frontal notch
Nasal part Nasal spine Glabella
B
Nasal spine Glabella Opening of frontal sinus
Supraorbital notch
Superciliary arch Trochlear fovea
Orbital part, orbital surface
Supraorbital margin Lacrimal fossa
Zygomatic process
Anterior ethmoidal foramen Ethmoidal arch
Fig. 30.3 The frontal bone. A, Anterior view. B, Inferior view, including the articulations between the frontal, ethmoid and nasal bones. (With permission
from Waschke J, Paulsen F (eds), Sobotta Atlas of Human Anatomy, 15th ed, Elsevier, Urban & Fischer. Copyright 2013.)
margin ends laterally in a strong, prominent zygomatic process that laterally. From the centre of the notch posteriorly, the bone projects
articulates with the zygomatic bone. A line curves posterosuperiorly anteroinferiorly behind the nasal bones and the frontal processes of the
from the process and divides into superior and inferior temporal lines, maxillae, and supports the nasal bridge. The region ends in a sharp
which are continued on the squamous part of the temporal bone. The nasal spine, on each side of which a small grooved surface partly roofs
area of the frontal bone below and behind the temporal lines is known the ipsilateral nasal cavity. The nasal spine makes a very small contribu
as the temporal surface and forms the anterior part of the temporal tion to the nasal septum; it articulates anteriorly with the crest of the
fossa. The parietal (posterior) margin is thick, deeply serrated, and nasal bones and posteriorly with the perpendicular plate of the ethmoid
bevelled internally above and externally below. Inferiorly, it becomes a bone.
rough, triangular surface that articulates with the greater wing of the
sphenoid. Orbital parts
The internal surface of the frontal bone is concave. Its upper, median,
part displays a vertical sulcus whose edges unite below as the frontal


Most of the frontal bone is thick and consists of trabecular tissue lying
crest. The sulcus contains the anterior part of the superior sagittal sinus.
between two compact laminae. In contrast, the orbital plates consist
The crest ends in a small notch that is completed by the ethmoid bone
entirely of compact bone and are thin and often translucent posteriorly;
to form a foramen caecum. The anterior portion of the falx cerebri is
indeed, they may be partly absorbed in old age.
attached to the margins of the sulcus and to the frontal crest. The in
The orbital plates form the largest part of the orbital roofs and are
ternal surface shows impressions of cerebral gyri, small furrows for
two thin, curved, triangular laminae separated by a wide ethmoidal
meningeal vessels, and granular foveolae for arachnoid granulations
notch. The orbital surface of each plate is smooth and concave, and
near the sagittal sulcus.
bears a shallow anterolateral fossa for the lacrimal gland. The troch
lear fovea (or spine) for attachment of a fibrocartilaginous trochlea,
Nasal part
through which the tendon of superior oblique plays, lies below and
behind the medial end of the supraorbital margin, midway between
The nasal part of the frontal bone lies between the supraorbital margins. the supraorbital notch and frontolacrimal suture. The convex cerebral
A serrated nasal notch articulates with the nasal bones inferiorly and surface is marked by frontal gyri and faint grooves for meningeal
with the frontal processes of the maxillae and the lacrimal bones vessels.


Face and scalp
480
4
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The quadrilateral ethmoidal notch is occupied by the cribriform walls of the orbit, the nasal septum, and the roof and lateral walls of
plate of the ethmoid bone. Inferior to its lateral margins, the bone the nasal cavity. It has a horizontal perforated cribriform plate, a median
articulates with the labyrinths of the ethmoid bone, and impressions perpendicular plate, and two lateral labyrinths that contain the ethmoi
of the ethmoidal air cells can be seen on this surface. Two transverse dal air cells.
grooves across each margin are converted into anterior and posterior
ethmoidal canals by articulation with the ethmoid bone; these canals Cribriform plate and crista galli
open on the medial orbital wall and transmit the anterior and posterior
ethmoidal nerves and vessels. The posterior borders of the orbital plates
The cribriform plate fills the ethmoidal notch of the frontal bone and
are thin and serrated, and articulate with the lesser wings of the sphe
forms a large part of the nasal roof. It derives its name from the fact
noid; their lateral parts usually appear in the middle cranial fossa
that it is penetrated by numerous foramina that transmit branches of
between the greater and lesser wings of the sphenoid.
the olfactory nerves and their associated meninges. A thick, smooth,
The frontal sinuses are two irregular cavities that ascend posterolat
triangular, median process, the crista galli, projects upwards from the
erally for a variable distance between the frontal laminae. They are
centre of the cribriform plate. The falx cerebri is attached to its thin and
separated by a thin septum and usually deflected from the median
curved posterior border, while its shorter, thick, anterior border articu
plane, which means that they are rarely symmetrical. The sinuses are
lates with the frontal bone by two small alae, so completing the foramen
variable in size and usually larger in males. Their openings lie anterior
caecum. Its sides are generally smooth, but may show slight bulges that
to the ethmoidal notch and lateral to the nasal spine, and each com
are related to underlying ethmoidal air cells. On both sides of the crista
municates with the middle meatus in the ipsilateral nasal cavity by a


galli, the cribriform plate is narrow and depressed, and is related to the
frontonasal canal.
gyrus rectus and the olfactory bulb, which lie above it. On each side of
The frontal sinuses are rudimentary at birth and can barely be dis
the crista anteriorly, there is a small slit occupied by dura mater. Just
tinguished. They show a primary expansion with eruption of the first
anterolateral to the slit, a foramen transmits the anterior ethmoidal
deciduous molars at about 18 months, and again when the permanent
nerve and vessels to the nasal cavity. A groove runs forwards to the
molars begin to appear in the sixth year. Growth is slow in the early
foramen caecum from the anterior ethmoidal canal.
years but it can be detected radiographically by 6 years. They reach full
size after puberty, although, with advancing age, osseous absorption
Perpendicular plate
may lead to further enlargement. Their degree of development appears
to be linked to the prominence of the superciliary arches, which is
thought to be a response to masticatory stresses. The frontal sinuses are The perpendicular plate is thin, flat, quadrilateral and median. It
described on page 566. descends from the cribriform plate to form the upper part of the nasal
septum, usually deviating slightly from the midline. Its anterior border
Ossification articulates with the nasal spine of the frontal bone and the crests of the
nasal bones, and its posterior border articulates with the crest of the
body of the sphenoid bone above and the vomer below. The thick
The frontal bone is ossified in fibrous mesenchyme from two primary
inferior border is attached to the nasal septal cartilage. Its surfaces are
centres that appear in the eighth week in utero, one near each frontal
smooth, except for above, where numerous grooves and canals that
tuber. Ossification extends superiorly, to form half of the main part of
transmit filaments of the olfactory nerves lead to medial foramina in
the bone; posteriorly, to form the orbital part; and inferiorly, to form
the cribriform plate.
nasal parts. Two secondary centres for the nasal spine appear about the


tenth year. At birth, the bone consists of two halves. The median suture
Ethmoidal labyrinths
usually closes in the first postnatal year, but may persist as the metopic
suture in a small percentage of individuals in various ethnic groups
(see Fig. 27.6A). The ethmoidal labyrinths consist of thinwalled ethmoidal air cells
between two vertical plates. The lateral surface (orbital plate) of the
labyrinth is part of the medial orbital wall. The air cells are arranged in
ETHMOID BONE anterior, middle and posterior groups. On average, there are 11 anterior
ethmoidal air cells, three middle and six posterior. In the disarticulated
The ethmoid bone is cuboidal and fragile (see Fig. 30.3B; Figs 30.4– bone, many air cells are open, but in life, and in the articulated skull,
30.6). It lies anteriorly in the cranial base and contributes to the medial they are closed by proximity to adjoining bones, except where they
Cribriform plate and foramina Fig. 30.4 A sagittal view of the facial
skeleton, viewed from the right side of
Frontal bone, squamous part, internal surface the nasal septum, looking towards the
left. (With permission from Waschke J,
Sphenoidal crest
Paulsen F (eds), Sobotta Atlas of
Crista galli
Sphenoidal sinus Human Anatomy, 15th ed, Elsevier,
Urban & Fischer. Copyright 2013.)
Hypophysial fossa Frontal sinus
Dorsum sellae
Frontonasal suture
Sphenoid, body
Ala of vomer
Ethmoid, perpendicular lamina
Bony nasal septum
Pterygoid process, medial plate Maxilla, frontal process
Pterygoid process, lateral plate
Posterior nasal spine
Vomer
Pterygoid hamulus
Palatine bone, horizontal plate Incisive canal
Maxilla, palatine process
Maxilla Palatine bone
Frontal bone Ethmoid
Nasal bone Vomer
Sphenoid Lacrimal bone


Bones of the facial skeleton and cranial vault
481
03
ReTpaHc
A
Cribriform plate and foramina
Superior concha
Sphenoidal sinus
Crista galli
Sphenopalatine foramen
Superior meatus
Sphenoid, body
Middle concha
Middle meatus
Maxillary hiatus
Clivus Inferior concha
Palatine bone, perpendicular plate
Inferior meatus
Pterygoid process, medial plate
Anterior nasal spine
Pterygoid hamulus
Palatine bone, horizontal plate Incisive canal
Maxilla, palatine process
B
Cribriform plate and foramina
Frontal sinus
Ethmoidal labyrinth
Opening of frontal sinus*
Opening of sphenoidal sinus
Sphenoidal sinus Superior concha
Sphenopalatine foramen
Palatine bone, ethmoidal crest
Inferior concha, ethmoidal process
Uncinate process
Parietal bone Sphenoid
Anterior nasal spine
Maxilla Occipital bone
Frontal bone Palatine bone
Maxillary hiatus
Nasal bone Ethmoid
Inferior concha Lacrimal bone
Incisive canal
* Probe located in the passage from the frontal sinus to the middle meatus
Fig. 30.5 A, B, Sagittal views of the facial skeleton, showing the floor of the anterior cranial fossa, the lateral wall of the nasal cavity, the hard palate and
the sphenoidal air sinus. In B, the middle concha in the lateral wall of the nasal cavity has been removed to reveal the uncinate process. (With
permission from Waschke J, Paulsen F (eds), Sobotta Atlas of Human Anatomy, 15th ed, Elsevier, Urban & Fischer. Copyright 2013.)
open into the nasal cavity. The superior surface is crossed by two grooves air cells lying anterior to the orbital plate are completed by the lacrimal
that are converted into the anterior and posterior ethmoidal canals by bone and frontal process of the maxilla.
the frontal bone; it shows open air cells that are covered by the edges A thin, curved uncinate process, variable in size, projects postero
of the ethmoidal notch of the frontal bone. On the posterior surface, inferiorly from the labyrinth. The upper edge of this process is a medial


open air cells are covered by the sphenoidal conchae and the orbital boundary of the hiatus semilunaris in the middle meatus. The uncinate
process of the palatine bone. The middle and posterior ethmoidal air process appears in the medial wall of the maxillary sinus as it crosses
cells are covered by a thin, smooth, oblong orbital plate that articulates the ostium of the maxillary sinus to join the ethmoidal process of the
superiorly with the orbital plate of the frontal bone, inferiorly with inferior nasal concha.
the maxilla and orbital process of the palatine bone, anteriorly with the The medial surface of the labyrinth forms part of the lateral nasal
lacrimal bone, and posteriorly with the sphenoid bone. The walls of the wall. It appears as a thin lamella that descends from the inferior surface


Face and scalp
482
4
nOITces
A Fig. 30.6 A, A sagittal view of the
facial skeleton, showing the bones
forming the lateral wall of the left
Frontal bone, squamous part, internal surface orbit and the maxillary air sinus.
B, The bones forming the medial
Sphenofrontal suture
wall and the floor of the left orbit.
(With permission from Waschke J,
Temporal bone, squamous part Sphenoid, greater wing, orbital surface Paulsen F (eds), Sobotta Atlas of
Human Anatomy, 15th ed, Elsevier,
Urban & Fischer. Copyright 2013.)
Sphenoid, greater wing
Zygomatico-orbital foramina
Sphenoid, body
Infraorbital canal
Sphenoidal sinus
Maxillary sinus
Pterygoid canal
Foramen rotundum
Pterygopalatine fossa
Pterygoid hamulus Greater palatine canal
B
Anterior ethmoidal foramen
Ethmoidolacrimal suture
Posterior ethmoidal foramen
Optic canal
Lacrimal bone, posterior lacrimal crest
Ethmoid, orbital plate
Infraorbital groove
Sphenoid, body
Palatine bone, orbital process
Maxilla, zygomatic process
Sphenopalatine foramen
Pterygopalatine fossa
Pterygoid hamulus
Parietal bone Sphenoid
Maxilla Palatine bone
Frontal bone Ethmoid
Nasal bone Lacrimal bone
Temporal bone Zygomatic bone
of the cribriform plate and ends as the convoluted middle nasal concha. drainage point for the frontal sinus. (The ethmoidal air cells are
Superiorly, the surface contains numerous vertical grooves that transmit described further on page 568.)
bundles of olfactory nerves. Posteriorly, it is divided by the narrow,
Ossification
oblique superior meatus, bounded above by the thin, curved superior
nasal concha. Posterior ethmoidal air cells open into the superior
meatus. The convex surface of the middle nasal concha extends along The ethmoid bone ossifies in the cartilaginous nasal capsule from three
the entire medial surface of the labyrinth, anteroinferior to the superior centres: one in the perpendicular plate, and one in each labyrinth. The


meatus. Its lower edge is thick, and its lateral surface is concave and latter two appear in the orbital plates between the fourth and fifth
forms part of the middle meatus. Middle ethmoidal air cells produce a months in utero, and extend into the ethmoidal conchae. At birth, the
swelling, the bulla ethmoidalis, on the lateral wall of the middle labyrinths, although illdeveloped, are partially ossified, and the
meatus, and open into the meatus, either on the bulla or above it. A remainder are cartilaginous. The perpendicular plate begins to ossify
curved infundibulum extends up and forwards from the middle meatus from the median centre during the first year, and fuses with the laby
and communicates with the anterior ethmoidal sinuses. In more than rinths early in the second year. The cribriform plate is ossified partly
half of crania it continues up as the frontonasal duct to include the from the perpendicular plate and partly from the labyrinths. The crista


Bones of the facial skeleton and cranial vault
483
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galli ossifies during the second year. The parts of the ethmoid bone lateral and mesial). The external surface has a descending concavo
unite to form a single bone at around 3 years of age. Ethmoidal air cells convex profile and is transversely convex. It is covered by procerus and
begin to develop at about 3 months in utero, and are therefore present nasalis, and perforated centrally by a small foramen that transmits a
at birth; however, they are difficult to visualize radiographically until vein. The internal surface, transversely concave, bears a longitudinal
the end of the first year. They grow slowly and have almost reached groove that houses the anterior ethmoidal nerve. The superior border,
adult size by the age of 12 years. thick and serrated, articulates with the nasal part of the frontal bone.
The inferior border, thin and notched, is continuous with the lateral
nasal cartilage. The lateral border articulates with the frontal process of
INFERIOR NASAL CONCHA the maxilla. The medial border, thicker above, articulates with its fellow
and projects behind as a vertical crest, thereby forming a small part of
The inferior nasal conchae are curved horizontal laminae in the lateral the nasal septum. It articulates from above with the nasal spine of the
nasal walls (see Fig. 30.5). Each has two surfaces (medial and lateral), frontal bone, the perpendicular plate of the ethmoid bone, and the
two borders (superior and inferior) and two ends (anterior and poste nasal septal cartilage.
rior). The medial surface is convex, much perforated, and longitudinally
grooved by vessels. The lateral surface is concave and part of the inferior Ossification
meatus. The superior border, thin and irregular, may be divided into
three regions: an anterior region articulating with the conchal crest of
Ossification is from a centre that appears early in the third month in
the maxilla; a posterior region articulating with the conchal crest of the
utero in the mesenchyme overlying the cartilaginous anterior part of the
palatine bone; and a middle region with three processes, which are
nasal capsule.


variable in size and form. The lacrimal process is small and pointed,
and lies towards the front. It articulates apically with a descending
process from the lacrimal bone, and at its margins with the edges of VOMER
the nasolacrimal groove on the medial surface of the maxilla, thereby
helping to complete the nasolacrimal canal. Most posteriorly, a thin The vomer is thin, flat and almost trapezoid (see Fig. 30.4). It forms
ethmoidal process ascends to meet the uncinate process of the ethmoid
the posteroinferior part of the nasal septum and presents two surfaces
bone. An intermediate thin maxillary process curves inferolaterally to
and four borders. Both surfaces are marked by grooves for nerves and
articulate with the medial surface of the maxilla at the opening of the
vessels. A prominent groove for the nasopalatine nerve and vessels lies
maxillary sinus. The inferior border is thick and spongiose, especially
obliquely in an anteroinferior plane. The superior border is thickest,
in its mid part. Both the anterior and posterior ends of the inferior nasal
and possesses a deep furrow between projecting alae, which fits the
concha are more or less tapered, the posterior more so than the
rostrum of the body of the sphenoid bone. The alae articulate with the
anterior.
sphenoidal conchae, the vaginal processes of the medial pterygoid
plates of the sphenoid bone, and the sphenoidal processes of the pala
Ossification
tine bones. Where each ala lies between the body of the sphenoid and
the vaginal process, its inferior surface helps to form the vomerovaginal
Ossification is from one centre that appears at about the fifth month in canal. The inferior border articulates with the median nasal crests of the
utero in the incurved lower border of the cartilaginous lateral wall of maxilla and palatine bones. The anterior border is the longest, and
the nasal capsule. The inferior concha loses continuity with the nasal articulates in its upper half with the perpendicular plate of the ethmoid
capsule during ossification. bone. Its lower half is cleft to receive the inferior margin of the nasal


septal cartilage. The concave posterior border is thick and bifid above
and thin below; it separates the posterior nasal apertures. The anterior
LACRIMAL BONE extremity of the vomer articulates with the posterior margin of the
maxillary incisor crest and descends between the incisive canals.
The lacrimal bones are the smallest and most fragile of the cranial bones Inability to identify the vomer during antenatal ultrasound scanning
and lie anteriorly in the medial walls of the orbits (see Figs 30.5B, in the first and early second trimesters of pregnancy has been suggested
30.6B). Each has two surfaces (medial and lateral) and four borders as a marker for trisomy 13 or 21, with a diagnostic accuracy of 0.985
(anterior, posterior, superior and inferior). The lateral (orbital) surface (Mihailovic et al 2012).
is divided by a vertical posterior lacrimal crest. Anterior to the crest is
a vertical groove whose anterior edge meets the posterior border of the Ossification
frontal process of the maxilla to complete the fossa that houses the
lacrimal sac. The medial wall of the groove is prolonged by a descending
The nasal septum is at first a plate of cartilage, part of which is ossified
process that contributes to the formation of the nasolacrimal canal by
above to form the perpendicular plate of the ethmoid. Its anteroinferior
joining the lips of the nasolacrimal groove of the maxilla and the lac
region persists as septal cartilage. The vomer is ossified in a layer of
rimal process of the inferior nasal concha. A smooth part of the medial
connective tissue, which covers the cartilage posteroinferiorly on each
orbital wall lies behind the posterior lacrimal crest; the lacrimal part of
aspect. At about the eighth week in utero, two centres appear flanking
orbicularis oculi is attached to this surface and crest. The surface ends
the midline, and in the twelfth week these unite below the cartilage, to
below in the lacrimal hamulus, which, together with the maxilla, com
form a deep groove for the nasal septal cartilage. Union of the bony
pletes the upper opening of the nasolacrimal canal. The hamulus may


lamellae progresses anterosuperiorly while the intervening cartilage is
appear as a separate lesser lacrimal bone. The anteroinferior region of
absorbed. By puberty, the lamellae are almost united, but evidence of
the medial (nasal) surface is part of the middle meatus. Its posterosu
their bilaminar origin remains in the everted alae and anterior marginal
perior part meets the ethmoid to complete some of the anterior eth
groove.
moidal air cells. The anterior border of the lacrimal bone articulates
with the frontal process of the maxilla, the posterior border with the
orbital plate of the ethmoid bone, the superior border with the frontal ZYGOMATIC BONE
bone, and the inferior border with the orbital surface of the maxilla.
Each zygomatic bone forms the prominence of a cheek, contributes to
Ossification
the floor and lateral wall of the orbit, and the walls of the temporal and
infratemporal fossae, and completes the zygomatic arch. Each is roughly
Ossification is from a centre that appears at about the twelfth week in quadrangular and is described as having three surfaces, five borders and
utero in mesenchyme around the nasal capsule. In later life, the lacrimal two processes (Fig. 30.7).
bone is subject to patchy erosion. The lateral (facial) surface is convex and is pierced near its orbital
border by the zygomaticofacial foramen, which is often double and
occasionally absent, and transmits the zygomaticofacial nerve and
NASAL BONE vessels. This surface gives attachment to zygomaticus major posteriorly
and zygomaticus minor anteriorly. The posteromedial (temporal)
The nasal bones are small, oblong, variable in size and form, and placed surface has a rough anterior area for articulation with the zygomatic
side by side between the frontal processes of the maxillae (see Figs 30.4, process of the maxilla, and a smooth, concave posterior area that
30.5, 30.6B). They jointly form the nasal bridge. Each nasal bone has extends up posteriorly on its frontal process as the anterior aspect of


two surfaces (external and internal) and four borders (superior, inferior, the temporal fossa. It also extends back on the medial aspect of the


Face and scalp
484
4
nOITces
A B Zygomatico-orbital foramen
Articulation with frontal bone Orbital surface Maxillary margin
Frontal process
Orbital margin Frontal process
Sphenoidal margin
Levator labii superioris
Temporal margin Zygomaticotemporal foramen
Maxillary margin
Temporal surface
Zygomaticofacial foramen Zygomaticus major
Articulation with temporal bone
Zygomaticus minor
Temporal process Temporal process
Body
Masseter
Articulation with maxilla
Fig. 30.7 The zygomatic bone. A, Anterolateral aspect, showing muscle attachments. B, Posterolateral aspect.
temporal process as an incomplete lateral wall for the infratemporal Anterior surface
fossa. The zygomaticotemporal foramen pierces this surface near the
This surface faces anterolaterally and displays inferior elevations over
base of the frontal process. The smooth and concave orbital surface
lying the roots of teeth. There is a shallow incisive fossa above the
forms the anterolateral part of the floor and adjoining lateral wall of
incisors to which depressor septi is attached. A slip of orbicularis oris
the orbit, and extends up on the medial aspect of its frontal process. It
is attached to the alveolar border below this fossa, and nasalis is
usually bears zygomaticoorbital foramina that represent the openings
attached superolateral to it. Lateral to the incisive fossa is a larger,
of canals leading to the zygomaticofacial and zygomaticotemporal
deeper canine fossa; levator anguli oris is attached to the bone of this
foramina.
fossa. The incisive and canine fossae are separated by the canine emi
The smoothly concave anterosuperior (orbital) border forms the
nence, which overlies the socket of the canine tooth. The infraorbital
inferolateral circumference of the orbital opening, and separates the
foramen lies above the fossa and transmits the infraorbital vessels and
orbital and lateral surfaces of the bone. The anteroinferior (maxillary)
nerve. Above the foramen, a sharp border separates the anterior and
border articulates with the maxilla. Its medial end tapers to a point


orbital surfaces of the bone and contributes to the infraorbital margin.
above the infraorbital foramen. A part of levator labii superioris is
Levator labii superioris is attached here above the infraorbital foramen
attached at this surface. The posterosuperior (temporal) border is
and levator anguli oris below it. Medially, the anterior surface ends at
sinuous, convex above and concave below, and is continuous with the
a deeply concave nasal notch, terminating in a pointed process that,
posterior border of the frontal process and upper border of the zygo
with its contralateral fellow, forms the anterior nasal spine. Nasalis and
matic arch. The temporal fascia is attached to this border. There is often
depressor septi are attached to the anterior surface near the notch.
a small, easily palpable, marginal tubercle below the frontozygomatic
suture. The posteroinferior border is roughened for the attachment of Infratemporal surface
masseter. The serrated posteromedial border articulates with the greater This surface is concave and faces posterolaterally, forming the anterior
wing of the sphenoid bone above, and the orbital surface of the maxilla wall of the infratemporal fossa. It is separated from the anterior surface
below. Between these serrated regions a short, concave, nonarticular by the zygomatic process and a ridge (jugal crest) that ascends to it from
part usually forms the lateral edge of the inferior orbital fissure. Occa the first molar socket. Near its centre are the openings of two or three
sionally absent, the fissure is then completed by the articulation of the alveolar canals, which transmit posterior superior alveolar vessels and
maxilla and sphenoid (or with a small sutural bone between them). nerves. Posteroinferior is the maxillary tuberosity, roughened supero
The frontal process, thick and serrated, articulates above with the medially where it articulates with the pyramidal process of the palatine
zygomatic process of the frontal bone and behind with the greater wing bone. A few fibres of medial pterygoid are attached here. Above the


of the sphenoid bone. A tubercle of varying size and form, Whitnall’s tuberosity, the smooth anterior boundary of the pterygopalatine fossa
tubercle, is usually present on its orbital aspect, within the orbital is grooved by the maxillary nerve as it passes laterally and slightly
opening and about 1 cm below the frontozygomatic suture. This tuber upwards into the infraorbital groove on the orbital surface.
cle provides attachment for the lateral palpebral ligament, the suspen
Orbital surface
sory ligament of the eye, and part of the aponeurosis of levator palpebrae
superioris. The temporal process, directed backwards, has an oblique, This surface is smooth and triangular, and forms most of the floor of
serrated end that articulates with the zygomatic process of the temporal the orbit. Anteriorly, its medial border bears a lacrimal notch, behind
bone to complete the zygomatic arch. which it articulates with the lacrimal bone, the orbital plate of the
ethmoid and, posteriorly, with the orbital process of the palatine bone.
Ossification Its posterior border is smoothly rounded and forms most of the anterior
edge of the inferior orbital fissure. The infraorbital groove lies centrally.
The anterior border is part of the orbital margin, and is continuous
Ossification is from one centre that appears in fibrous tissue about the
medially with the lacrimal crest of the frontal process of the maxilla.
eighth week in utero. The bone is sometimes divided by a horizontal
The infraorbital groove transmits the infraorbital vessels and nerve, and
suture into a larger upper and smaller lower part.
begins midway on the posterior border, where it is continuous with a
groove on the posterior surface. It passes forwards into the infraorbital
MAXILLA canal, which opens on the anterior surface below the infraorbital
margin. Near its midpoint, the infraorbital canal gives off a small lateral
branch, the canalis sinuosus, which transmits the anterior superior
The maxillae are the largest of the facial bones, other than the mandible,
alveolar nerve and vessels. The canalis sinuosus descends in the orbital
and jointly form the whole of the upper jaw. Each bone forms the


floor lateral to the infraorbital canal, curves medially in the anterior
greater part of the floor and lateral wall of the nasal cavity, and of the
wall of the maxillary sinus, and then passes below the infraorbital
floor of the orbit; contributes to the infratemporal and pterygopalatine
foramen to the margin of the anterior nasal aperture in front of the
fossae; and bounds the inferior orbital and pterygomaxillary fissures.
anterior end of the inferior concha. It follows the lower margin of the
Each maxilla has a body and four processes, namely: the zygomatic,
aperture and opens near the nasal septum in front of the incisive canal.
frontal, alveolar and palatine processes (see Fig. 30.6; Fig. 30.8).
The site of the attachment of inferior oblique may be indicated by a
small depression in the bone at the anteromedial corner of the orbital
Body
surface, lateral to the lacrimal groove.
Nasal surface
The body of the maxilla is roughly pyramidal, and has anterior,
infratemporal (posterior), orbital and nasal surfaces that enclose the This surface displays posterosuperiorly a large, irregular maxillary hiatus
maxillary sinus. that leads into the maxillary sinus. Parts of air sinuses that are


Bones of the facial skeleton and cranial vault
485
03
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Fig. 30.8 A, The maxilla, lateral view.
B, The maxilla and palatine bone,
A Lacrimal margin
medial view. (With permission from
Waschke J, Paulsen F (eds), Sobotta
Frontal process, anterior lacrimal crest Lacrimal notch Atlas of Human Anatomy, 15th ed,
Elsevier, Urban & Fischer. Copyright
Infraorbital margin 2013.)
Infraorbital foramen
Infraorbital groove
Canine fossa Orbital surface
Infratemporal surface
Nasal notch
Alveolar foramina
Anterior nasal spine Zygomatic process
Maxillary tuberosity
Anterior surface
Alveolar process
B
Maxillary hiatus
Lacrimal margin
Ethmoidal crest
Frontal process
Sphenopalatine notch
Lacrimal groove
Maxillary sinus
Conchal crest
Palatine bone, perpendicular plate
Nasal surface
Conchal crest
Anterior nasal spine
Posterior nasal spine
Palatine process
Maxilla
Palatine bone
completed by articulation with the ethmoid and lacrimal bones lie at lacrimal crest, which gives attachment to the medial palpebral ligament
the upper border of the hiatus. The smooth concave surface below the and is continuous below with the infraorbital margin. A small, palpable
hiatus is part of the inferior meatus. Posteriorly, the surface is rough tubercle at the junction of the crest and orbital surface is a guide to the
ened where it articulates with the perpendicular plate of the palatine lacrimal sac. The smooth area anterior to the lacrimal crest merges
bone. This surface is traversed by a groove that descends forwards from below with the anterior surface of the body of the maxilla. Parts of
the midposterior border, and is converted into a greater palatine canal orbicularis oculi and levator labii superioris alaeque nasi are attached
by the perpendicular plate. Anterior to the hiatus, a deep nasolacrimal here. Behind the crest, a vertical groove combines with a groove on the
groove, continuous above with the lacrimal groove, makes up about lacrimal bone to complete the lacrimal fossa. The medial surface is part


twothirds of the circumference of the nasolacrimal canal. The rest is of the lateral nasal wall. A rough subapical area articulates with the
contributed by the descending part of the lacrimal bone and the lac ethmoid, and closes anterior ethmoidal air cells. Below this, an oblique
rimal process of the inferior nasal concha. This canal conveys the naso ethmoidal crest articulates posteriorly with the middle nasal concha,
lacrimal duct to the inferior meatus. More anteriorly, an oblique conchal and anteriorly underlies the agger nasi, a ridge anterior to the concha
crest articulates with the inferior nasal concha. The concavity below it on the lateral nasal wall. The ethmoidal crest forms the upper limit of
is part of the inferior meatus, while the surface above it is part of the the atrium of the middle meatus. The frontal process articulates above
atrium of the middle meatus. with the nasal part of the frontal bone. Its anterior border articulates
with the nasal bone and its posterior border articulates with the lac
Zygomatic process rimal bone.
Anterior, infratemporal and orbital surfaces of the maxilla converge at Alveolar process
a pyramidal projection, the zygomatic process. Anteriorly, the process
merges into the facial surface of the body of the maxilla. Posteriorly, it
The alveolar process is thick and arched, wide behind, and socketed
is concave and continuous with the infratemporal surface. Superiorly,
for the roots of the upper teeth. The eight sockets on each side vary
it is roughly serrated for articulation with the zygomatic bone. Inferi
according to the tooth type. The socket for the canine is deepest, the
orly, a bony arched ridge, the zygomaticoalveolar ridge or jugal crest,
sockets for the molars are widest and subdivided into three by
separates the facial (anterior) and infratemporal surfaces.
septa, those for the incisors and second premolar are single, and that
for the first premolar is usually double. Buccinator is attached to the
Frontal process
external alveolar aspect as far forwards as the first molar. In articu
lated maxillae, the processes form the alveolar arch. Occasionally, a


The frontal process projects posterosuperiorly between the nasal and variably prominent maxillary torus is present in the midline of the
lacrimal bones. Its lateral surface is divided by a vertical anterior palate.


Face and scalp
486
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nOITces
Palatine process Orbital surface Air sinus on
sphenoidal aspect
The palatine process, thick and horizontal, projects medially from the Orbital process
lowest part of the medial aspect of the maxilla. It forms a large part of
Articular surface
the nasal floor and hard palate, and is much thicker in front. Its infer Lateral suface
ior surface is concave and uneven, and with its contralateral fellow it
Sphenoidal process
forms the anterior threequarters of the osseous (hard) palate. The
Sphenopalatine notch
palatine process displays numerous vascular foramina and depressions
for palatine glands and, posterolaterally, two grooves that transmit the Perpendicular plate
greater palatine vessels and nerves. The infundibular incisive fossa is Greater palatine groove
placed between the two maxillae, behind the incisor teeth. The median Conchal crest
intermaxillary palatal suture runs posterior to the fossa, and although
a little uneven, is usually relatively flat on its oral aspect. Its bony Horizontal plate
margins are sometimes raised into a prominent longitudinal palatine Articulates with lateral
pterygoid plate
torus. Two lateral incisive canals, each ascending into its half of the
nasal cavity, open in the incisive fossa; they transmit the terminations Musculus uvulae
on posterior
of the greater palatine artery and nasopalatine nerve. Two additional nasal spine
median openings, anterior and posterior incisive foramina, are occa
sionally present; they transmit the nasopalatine nerves, the left usually Pyramidal process A mr eti dc iu al la pte tes r w ygit oh id
passing through the anterior, and the right through the posterior plate
foramen. On the inferior palatine surface, a fine groove, sometimes
Medial pterygoid
termed the incisive suture, and prominent in young skulls, may be
Fig. 30.9 The palatine bone, posterior view.
observed in adults. It extends anterolaterally from the incisive fossa to
the interval between the lateral incisor and canine teeth. The superior
surface of the palatine process is smooth, is concave transversely, and Horizontal plate


forms most of the nasal floor. The incisive canal lies anteriorly, near its
median margin. The lateral border is continuous with the body of the The horizontal plate is quadrilateral, with two surfaces (nasal and pala
maxilla. The medial border, thicker in front, is raised into a nasal crest tine) and four borders (anterior, posterior, lateral and medial). The
that, with its contralateral fellow, forms a groove for the vomer. The nasal surface, transversely concave, forms the posterior nasal floor. The
front of this ridge rises higher as an incisor crest, prolonged forwards palatine surface forms the posterior quarter of the bony palate with its
into a sharp process that, with its fellow, forms an anterior nasal spine. contralateral fellow. There is often a curved palatine crest near its pos
The posterior border is serrated for articulation with the horizontal terior margin. The posterior border is thin and concave; the expanded
plate of the palatine bone. tendon of tensor veli palatini is attached to it and to its adjacent surface
behind the palatine crest. Medially, with its contralateral fellow, the
Maxillary sinus posterior border forms a median posterior nasal spine to which the
uvular muscle is attached. The anterior border is serrated and articulates
with the palatine process of the maxilla. The lateral border is continu
The maxillary sinus is the largest of the paranasal sinuses and is situated
ous with the perpendicular plate of the palatine bone and is marked by
in the body of the maxilla. It is described in detail on page 568.
a greater palatine groove. The medial border is thick and serrated, and
articulates with its contralateral fellow in the midline, forming the
Ossification
posterior part of the nasal crest which articulates with the posterior part
of the lower edge of the vomer.
The maxilla ossifies from a single centre in a sheet of mesenchyme that
appears above the canine fossa at about the sixth week in utero and Perpendicular plate
spreads into the rest of the maxilla and its processes. The pattern of
spread of ossification may initially leave an unmineralized zone roughly
The perpendicular plate is thin and oblong, and has two surfaces (nasal
corresponding to a site where a premaxillary suture may occur. However,


and maxillary) and four borders (anterior, posterior, superior and in
this deficiency is soon ossified; there is no evidence of a separate centre
ferior) (see Figs 30.8B, 30.9). The nasal surface bears two crests (conchal
of ossification for the incisorbearing portion of the maxilla (i.e.
and ethmoidal) and shows areas that contribute to the inferior, middle
premaxilla).
and superior meatuses. Inferiorly, the nasal surface is concave where it
The maxillary sinus appears as a shallow groove on the nasal aspect
contributes to part of the inferior meatus. Above this is a horizontal
at about the fourth month in utero. Though small at birth, the sinus is
conchal crest that articulates with the inferior concha. Above the
identifiable radiologically. After birth, it enlarges with the growing
conchal crest, the surface presents a shallow depression that forms part
maxilla, though it is only fully developed following the eruption of the
of the middle meatus; it is limited above by an ethmoidal crest for the
permanent dentition. The infraorbital vessels and nerve are, for a time,
middle nasal concha, above which a narrow, horizontal groove forms
in an open groove in the orbital floor; the anterior part of the groove
part of the superior meatus.
is subsequently converted into a canal by a lamina that grows in from
The maxillary surface is largely rough and irregular, and articulates
the lateral side.
with the nasal surface of the maxilla. Posterosuperiorly, it forms a
At birth, the transverse and sagittal maxillary dimensions are greater
smooth medial wall to the pterygopalatine fossa. Its anterior area, also
than the vertical. The frontal process is prominent, but the body is little
smooth, overlaps the maxillary hiatus from behind to form a posterior
more than an alveolar process because the alveoli reach almost to the
part of the medial wall of the maxillary sinus. A deep, obliquely
orbital floor. In adults, the vertical dimension is the greatest, reflecting
descending greater palatine groove (converted into a canal by the
the development of the alveolar process and enlargement of the sinus.
maxilla) lies posteriorly on this maxillary surface; it transmits the


When teeth are lost, the bone reverts towards its infantile shape; its
greater palatine vessels and nerve.
height diminishes, the alveolar process is absorbed, and the lower parts
The anterior border is thin and irregular. Level with the conchal crest,
of the bone contract and become reduced in thickness at the expense
a pointed lamina projects below and behind the maxillary process of
of the labial wall.
the inferior concha; it articulates with it and so appears in the medial
wall of the maxillary sinus. The posterior border articulates via a ser
rated suture with the medial pterygoid plate. It is continuous above with
PALATINE BONE the sphenoidal process of the palatine bone and expands below into
its pyramidal process. Orbital and sphenoidal processes project from
The palatine bones are posteriorly placed in the nasal cavity, between the superior border and are separated by the sphenopalatine notch,
the maxillae and the pterygoid processes of the sphenoid bones. They which is converted into a foramen by articulation with the body of the
contribute to the floor and lateral walls of the nose, to the floor of the sphenoid. This foramen connects the pterygopalatine fossa to the pos
orbit and the hard palate, to the pterygopalatine and pterygoid fossae, terior part of the superior meatus, and transmits sphenopalatine vessels
and to the inferior orbital fissures. Each has two plates (horizontal and and the posterior superior nasal nerves. The inferior border is continu
perpendicular), arranged as an Lshape, and three processes (pyramidal, ous with the lateral border of the horizontal plate and bears the lower
orbital and sphenoidal) (Fig. 30.9). end of the greater palatine groove in front of the pyramidal process.


Bones of the facial skeleton and cranial vault
487
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Pyramidal process foramina, damage branches of the trigeminal nerve and result in sensory
deficits. Fracture configurations vary according to the amount of energy
absorbed and local anatomical factors that constitute sites of
The pyramidal process slopes down posterolaterally from the junction
weakness.
of the horizontal and perpendicular palatine plates into the angle
The direction and magnitude of the applied forces determine the
between the pterygoid plates of the sphenoid bone. On its posterior
displacement of these fractures, which are modified according to muscle
surface, a smooth, grooved triangular area, limited on each side by
attachments and the state of the dentition. For example, an unerupted
rough articular furrows that articulate with the pterygoid plates, com
mandibular third molar may produce a weak point at the mandibular
pletes the lower part of the pterygoid fossa. Anteriorly, the lateral surface
angle.
articulates with the maxillary tuberosity. This area gives attachment to
The lateral pterygoid muscles frequently displace a fractured man
fibres of the superficial head of medial pterygoid. Posteriorly, a smooth
dibular condyle medially. Masseter, temporalis and medial pterygoid
triangular area appears low in the infratemporal fossa between the
may stabilize fractures of the mandible when vertically or horizontally
tuberosity and the lateral pterygoid plate. The inferior surface, near its
favourable, but displace those that are vertically and horizontally unfa
union with the horizontal plate, bears the lesser palatine foramina,
vourable. Severe injuries to the middle third of the face may result in
which transmit the lesser palatine nerves and vessels.
craniofacial dysjunction, the middle third sliding inferiorly down the
angulated and strong anterior skull base. This causes an apparent
Orbital process
lengthening of the face and a dishfaced appearance. Airway obstruction
may result from this downward and backward displacement. Fractures
The orbital process is directed superolaterally from in front of the per of the anterior mandible may cause loss of support of the muscles


pendicular plate and has a constricted ‘neck’. It encloses an air sinus controlling the anterior tongue position and may also contribute to loss
and presents three articular and two nonarticular surfaces. Of the artic of the airway.
ular surfaces, the oblong anterior (maxillary) surface faces down and Although the fractures caused by severe injuries are often complex,
anterolaterally, and articulates with the maxilla. The posterior (sphenoi it is convenient to describe them as arising in the upper, middle and
dal) surface is directed up and posteromedially, and bears the opening lower thirds of the face, even though fractures may involve one or more
of an air sinus. It usually communicates with the sphenoidal sinus and of these areas. Upper third fractures involve the frontal bones. Middle
is completed by a sphenoidal concha. The medial (ethmoidal) surface third fractures involve the nasoethmoidal complex, orbit, zygomatic
faces anteromedially and articulates with the labyrinth of the ethmoid complex and maxilla. Lower third fractures correspond to fractures of
bone. The sinus of the orbital process sometimes opens on the surface, the mandible (Video 30.1).
and communicates with the posterior ethmoidal air cells. More rarely,
it opens on both the ethmoidal and sphenoidal surfaces, and commu Upper third of face
nicates with both posterior ethmoidal air cells and the sphenoidal
sinus.
Fractures in the upper third of the face are almost invariably commin
Of the nonarticular surfaces, the triangular superior (orbital) surface
uted and are often associated with fractures of the middle third of the
is directed superolaterally to the posterior part of the orbital floor. The
face. Fractures of the frontal bone may involve the frontal sinuses and/
lateral surface is oblong, faces the pterygopalatine fossa, and is separ
or orbital roof. If the frontonasal duct is traumatized, its drainage may
ated from the orbital surface by a rounded border that forms a medial
be impaired, which predisposes to ascending intracranial infection and
part of the lower margin of the inferior orbital fissure. This surface may
mucocele development within the frontal sinuses (Eljamel and Foy
present a groove, directed superolaterally, for the maxillary nerve, and


1990; Fig. 30.10). This risk may be minimized with frontonasal stents
is continuous with the groove on the upper posterior surface of the
or frontonasal duct and frontal sinus obliteration with autogenous
maxilla. The border between the lateral and posterior surfaces descends
bone graft. Fractures that involve both the anterior and the posterior
anterior to the sphenopalatine notch.
walls of the frontal sinus also carry a risk of early and delayed intracra
nial infection, and often it is necessary to obliterate the frontal sinuses
Sphenoidal process
or cranialize the frontal sinuses in order to prevent this complication.
Cranialization of the frontal sinuses involves the removal of the poste
The sphenoidal process is a thin plate that is smaller and lower than rior wall and all frontal sinus mucosa, typically through a frontal crani
the orbital process, and is directed superomedially. Its superior surface otomy approach. Fractures of the posterior wall of the frontal sinus may
articulates with the sphenoidal concha and, above it, with the root of be associated with dural tears (and cerebrospinal rhinorrhoea), which
the medial pterygoid plate. It carries a groove that contributes to the must be repaired at the same time. Fractures involving the orbital roof
formation of the palatovaginal canal. The concave inferomedial surface may be associated with displacement of the globe of the eye, diplopia
forms part of the roof and lateral wall of the nose. Posteriorly, the lateral and supraorbital nerve injury.
surface articulates with the medial pterygoid plate, while its smooth
anterior region forms part of the medial wall of the pterygopalatine Middle third of face
fossa. The posterior border articulates with the vaginal process of the
medial pterygoid plate. The anterior border is the posterior edge of
The middle third of the face is defined as that area bounded above by
the sphenopalatine notch. The medial border articulates with the ala of
a transverse line connecting the two zygomaticofrontal sutures, passing
the vomer. The sphenopalatine notch, between the two processes, is
through the frontomaxillary and frontonasal sutures, and limited below


converted into a foramen by articulation with the body of the sphenoid
by the occlusal plane of the maxillary teeth. Posteriorly, the region is
bone.
limited by the sphenoethmoidal junction, but it includes the free
margins of the pterygoid plates inferiorly. Fractures of the middle third
Ossification
of the facial skeleton (Le Fort 1901) may involve the maxillae, palatine
bones, zygomatic bones, zygomatic processes of the temporal bones,
Ossification is in mesenchyme from one centre in the perpendicular nasal bones, vomer, ethmoid bone together with its nasal conchae, and
plate that appears during the eighth week in utero. From this centre, the body and greater and lesser wings of the sphenoid bone. A classifica
ossification spreads into all parts. At birth, the height of the perpendicu tion system that subdivides the fractures into central block fractures and
lar plate equals the width of the horizontal plate, but in adults it is those that involve the lateral middle third is now largely of historical
almost twice as great, a change in proportions that accords with those value, but finds use as an initial description that is later elaborated by
that occur in the maxilla. defining extensions of the fracture pattern into the upper third and the
cranium.
FRACTURES OF THE FACIAL SKELETON Central middle third of face
The majority of the skeleton of the central middle third is composed
Trauma to the face is common; outcomes are related to the mechanism of waferthin sheets of cortical bone with stronger reinforcements, i.e.
of the injury in terms of its severity and to delays in treatment. Both the palate and alveolar process; the lateral rim of the piriform aperture
soft and hard tissues are affected. Moderate to severe injuries produce extending upwards (via the canine fossa) to the medial orbital rim, and
facial skeletal disruption that compromises masticatory and orbital finally to the glabella; the zygomatic buttress and its connections to the
function. Inadequate skeletal support of soft tissues contributes to facial inferior and lateral orbital margins and the zygomatic arch; and the
asymmetry, and the additional loss of soft tissues and subsequent orbital rims and the pterygoid plates. Whatever the fracture configur


scarring merely compound this. Some fractures pass through neural ation, pterygoid plate disruption is seen in all examples of maxillary


Face and scalp
487.e1
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ReTpaHc
Fig. 30.10 A compound craniofacial fracture with disruption of the
anterior and posterior walls of the frontal sinus, torn dura, and intracranial
bone. Treatment is directed at establishing a safe sinus, i.e. sealing off
the frontonasal duct and removing all traces of sinus epithelium. It is also
important to establish an intact fronto-orbital bar, to enable an accurate
scaffold on which to attach the root of the nose and midface, if implicated
in the fracture pattern, and to assure good cosmesis.


Face and scalp
488
4
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fracture. The strength lies in the facial surface of the skeleton, which, downwards and backwards across the pterygopalatine fossa to involve
although thin in most areas, is crossbraced. The design is ideally suited the root of the pterygoid plates. The zygomatic arch is usually fractured
to transmit occlusal forces vertically to the skull base. at the zygomaticotemporal suture (Le Fort 1901).
Central middle third fractures may involve the nasoethmoidal Open reduction and internal fixation are conducted through aes
complex in isolation or as part of a more complex Le Fort pattern of thetically favourable incisions in the hairline, upper eyelid, oral cavity
injury. Le Fort I, II or III fractures inevitably involve the infratemporal and lower eyelid (subciliary and transconjunctival) (Fig. 30.13).
fossa. The bones of the midface transmit the forces of impact directly
Lateral middle third of face
to the cranium. The most important strut related to the infratemporal
and pterygopalatine fossae is the pterygomaxillary strut. Fractures Fractures of the lateral middle third involve the zygomaticomaxillary
involving this strut may extend elsewhere to involve the cranial base complex (Fig. 30.14). The zygomatic bone forms the prominence of
and orbit. The associated soft tissue damage that accompanies these the cheek. Since the most common cause of a zygomatic fracture is a
fractures may damage nerves, blood vessels and muscles. Injuries to the blow from a fist, depressed fractures of the zygomaticomaxillary
second or third divisions of the trigeminal nerve or the chorda tympani complex are a common injury. These injuries may be sustained in isola
nerve result in altered sensation to the oral cavity, face and jaws, includ tion or in association with orbital blowout fractures. Isolated zygomatic
ing impaired taste; fractures extending into the orbit may result in arch fractures from a welldirected lateral blow are also common.
decreased visual acuity and ophthalmoplegia, and neural damage to Classic zygomatic complex fractures involve the zygomaticomaxil


motor nerves or direct damage to muscles may result in problems with lary, zygomaticotemporal, zygomaticofrontal and sphenozygomatic
chewing, swallowing, speech, middle ear function and eye movements; sutures. The fracture line extends from the lateral wall of the orbit lat
injuries involving the pterygopalatine or otic ganglia interfere with erally into the infratemporal fossa at the zygomaticofrontal suture.
lacrimation, nasal secretions and salivation. Facial deformity with lack From this point, the fracture line extends inferiorly to join the most
of nasal projection asymmetry and occlusal disturbance and vertical lateral aspect of the inferior orbital fissure, continues inferiorly along
and anteroposterior malposition of the globe are often seen. the posterior surface of the zygomatic buttress – where it communicates
with the lateral bulge of the maxillary antrum – and runs around the
Nasoethmoidal complex Fractures may involve the osteocartilagi zygomatic buttress, high in the buccal sulcus in the upper molar region,
nous framework of the nose in isolation or as part of complex injuries and then extends upwards towards the infraorbital foramen. It finally
that also involve the paranasal sinuses and/or the orbits (Fig. 30.11). runs laterally along the floor of the orbit to reach the lateral extension
Simple fractures involve the nasal bones and/or frontal process of of the inferior orbital fissure. Clinical signs may include facial asym
the maxilla. Only if there is displacement of the bones is a closed reduc metry, infraorbital nerve paraesthesia/anaesthesia, limitation of mouth
tion of the fracture required. The terminal branch of the anterior eth opening (if there is impingement of the coronoid process by a depressed
moidal nerve and its accompanying vessels are at risk when injuries arch fracture) and signs of orbital blowout fracture (see below; Videos
involve the dorsum of the nose. 30.3 and 30.4).
Complex nasal injuries may include nasofrontal suture disjunction, As zygomatic fractures involve the maxillary sinus (the lateral wall
nasolacrimal and frontonasal duct injury, and fracture of the ethmoidal of which is frequently comminuted) and the infratemporal fossa, there


complex (Markowitz et al 1991). The skeletal foundation of the is potential for spread of infection between these structures and then
nasoethmoidal complex consists of a strong triangularshaped frame. via foraminae in the skull base to the middle cranial fossa. Patients with
However, all these structures are fragile and any force sufficient to frac zygomatic complex fractures must be advised to refrain from sneezing
ture the frame results in severe comminution and displacement. The or noseblowing, which may force air from the antrum into the sur
ethmoidal air cells act as a crumple zone protecting the skull base from rounding tissues (surgical emphysema) or into the orbit, resulting in
mechanical forces. A severe impact delivered to the midface, particularly proptosis of the eye. While the zygoma may be reduced transorally (the
over the bridge of the nose, may result in these structures being driven Keen approach) or via the brow (Dingman approach) or a cheekhook
backwards between the orbits. This may result in traumatic hyper technique (Poswillo approach), it is perhaps the Gillies temporal
telorism, producing an increase in distance between the pupils. Associ approach that is worthy of mention here because it exploits the anatomy
ated displacement of the medial canthal ligaments results in traumatic of the region (Gillies et al 1927). The incision is hidden in the hairline
telecanthus. Increased intercanthal distance (normal range 24–39 mm and the approach depends on the fact that the superior temporal fascia
in Caucasians) may be corrected using microplates, stainless steel wire is attached to the superior temporal line of the skull superiorly and the
and acrylic canthal splints. Damage to the lacrimal system requires zygomatic arch inferiorly, and that temporalis runs under the arch. An
approximation of the severed canalicular ends or dacryocystorhinos incision through the temporalis fascia, but not through the muscle,
tomy. Comminution of the cribriform plates of the ethmoid may result therefore allows a metal elevator to be passed from the hairline to the
in dural tears and cerebrospinal rhinorrhoea. Often, nasoethmoidal zygomatic arch and body. Outward traction, coupled with rotation,


fractures are combined with more extensive fractures of the frontal allows precise localization of the bone.
bone. The complexity of the injury has implications for subsequent
Orbital fractures The orbit is invariably involved in fractures of the
facial reconstruction (Video 30.2, Fig. 30.12).
zygomatic bone and in Le Fort II and III fractures. The orbit may also
Le Fort I fractures (Guerin’s fracture) Le Fort I fractures consist be involved in fractures of the frontal bone and extensive nasal complex
injuries. Direct blunt trauma to the globe may result in displacement
of a horizontal fracture line above the level of the floor of the nose
of the globe and fracture of the thin orbital floor (or medial wall)
involving the lower third of the nasal septum. The mobile segment
without associated rim involvement and is known as a ‘blowout’ frac
consists of the palate, the alveolar process and the lower thirds of the
ture (Ahmas et al 2006). This protective mechanism of injury helps to
pterygoid plates.
maintain the integrity of the globe itself in preference to the orbital
Le Fort II fractures (pyramidal fracture) Le Fort II fractures are walls. There may be associated herniation of periorbital fat (Fig. 30.15)
and/or inferior rectus, resulting in restriction of eye movement, diplo
pyramidal fractures involving the maxillary bones. From the nasal
pia, ipsilateral lowering of pupillary height, and enophthalmos (due to
bridge, the fracture enters the medial wall of the orbit to involve the
increased orbital volume) (Manson et al 1986). Fortunately, the optic
lacrimal bone and then crosses the inferior orbital rim, usually at the
foramen, which is situated within the lesser wing of the sphenoid bone,
junction of the medial third and lateral twothirds, and often involves
is surrounded by dense bone and is only rarely involved in fractures.
the infraorbital foramen. The fracture line then runs beneath the zygo
Direct injury to the optic nerve is therefore unusual. The orbital floor
maticomaxillary suture, traversing the lateral wall of the maxillary sinus
is normally repaired by the insertion of an alloplastic or autogenous
to extend posteriorly and horizontally across the pterygoid plates. The


graft (Fig. 30.16) (Ellis and Tan 2003).
zygomatic bones and arches remain attached to the skull base.
Le Fort III fractures Le Fort III fractures run parallel with the base Lower third of face (mandible)
of the skull, separating the entire midfacial skeleton from the cranial
base. The fracture extends through the nasal base and continues pos The mandible is essentially a tubular bone bent into a blunt V shape
teriorly across the ethmoid bone. The fracture then crosses the lesser (Ch. 32). This basic configuration is modified by sites of muscle attach
wing of the sphenoid and, on occasion, involves the optic foramen. ment, principally masseter and medial pterygoid at the angle, and
Usually, however, it slopes down medially, passing below the optic temporalis at the coronoid process. The presence of teeth, particularly
foramen to reach the pterygomaxillary fissure and pterygopalatine those with long roots such as the canines, or of unerupted teeth pro
fossa. From the base of the inferior orbital fissure, the fracture runs later duces lines of weakness in the mandible. When the teeth are lost or fail
ally and upwards, separating the greater wing of the sphenoid from the to develop, the subsequent progressive resorption of the alveolar bone
zygomatic bone, to reach the frontozygomatic suture. It also extends means that the mandible reverts to its underlying tubular structure. Like


Face and scalp
488.e1
03
ReTpaHc Fig. 30.11 An extended naso-orbito-ethmoid (NOE) fracture. The frontal
sinus and frontal bone fracture (red arrows) need to be reconstructed to
provide a stable platform for the NOE. The NOE fracture (blue arrows) Fig. 30.12 A typical high-energy pan-facial injury. This injury
extends into the anterior maxilla and blends with the extended demonstrates several complicated levels of Le Fort type maxillary
comminuted zygomatic fracture (green arrows). fracture. The red arrows demonstrate the Le Fort III pattern (although the
major fragment is further comminuted). The green arrows demonstrate the
Le Fort II pattern, and the dark blue arrows demonstrate the Le Fort I
pattern, although the maxilla is itself fractured sagittally (purple arrows).
There are also bilateral condylar neck fractures and a mandibular
symphysial fracture (light blue arrows). Note the avulsed lower left
premolar and dental fracture of the right incisor (yellow arrows). Exclusion
of inhaled dental teeth and fragments is important.
Fig. 30.13 Various examples of plating
configurations and titanium alloplastic
reconstructions. The aim of surgery is to
reconstruct anatomy in order to provide a scaffold
on which to overlay the soft tissues.


Face and scalp
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Fig. 30.14 A typical left zygomatic fracture. In this
case, navigation planning takes the normal green
right side and mirrors to the left. The red and
orange outlines indicate where the bone should
be.
Fig. 30.15 Image fusion of computed tomography and magnetic
resonance imaging, showing an extensive left medial wall fracture
(arrows). There is obvious herniation of orbital contents and disruption of
the soft tissue contents of the orbit.


Muscles of the face
489
03
ReTpaHc
all tubular bones, the strength of the mandible resides in a dense corti cerebrospinal fluid from the nose (rhinorrhoea) or ruptured tympanic
cal plate, thickened anteriorly and at its lower border; it follows that membrane (otorrhoea). Alternatively, if this membrane remains intact,
the mandible is strongest anteriorly in the midline and is progressively it may be seen as blue and bulging (haemotympanum).
weaker posteriorly towards the condylar processes. Again, like all
tubular bones, the mandible has great resistance to compressive forces,
but fractures at sites of tensile strain. It is liable to particular patterns SKELETAL ACCESS SURGERY
of distribution of tensile strain when forces are applied to it. Anterior
forces applied to the mental symphysis, or over the body of the man The craniofacial skeleton has an excellent blood supply and so can be
dible, lead to strain at the condylar necks and also along the lingual dismantled as a series of osteoplastic flaps. The surgical disarticulation
cortical plates on the contralateral side in the molar region. The man of the craniofacial skeleton has been used to gain access to otherwise
dible therefore often fractures at two sites and isolated fractures are inaccessible sites in order to allow the surgeon to attend to pathology
relatively unusual. In order of frequency, fractures occur most com in the skull base, cervical spine and anterior and posterior cranial fossae.
monly at the neck of the condyle, the angle, the parasymphysial region The aim is to provide increased and more direct exposure of both the
and the body of the mandible. pathology and the adjacent vital structures without the need to resect
uninvolved structures. The craniofacial skeleton can be divided into a
Condylar process
series of modular osteotomies, which permit both independent and
The condyle is protected from direct injury by the zygomatic arches. conjoined mobilization.
Fractures occur usually by the transmission of force following a blow The zygomatic and nasal bones and the maxilla may be exposed and


to the front of the mandible or to the contralateral body. Fractures are mobilized, and pedicled on the overlying soft tissues either unilaterally
seen at all levels of the condyle (Loukota et al 2005). Except in children, or bilaterally. These approaches improve access to the nasal cavity,
most condylar fractures are not intracapsular, and occur in the neck. maxillary, ethmoidal and sphenoidal sinuses, the soft palate and
They usually run obliquely downwards and backwards from the man nasopharynx, and the infratemporal fossa and pharyngeal space. The
dibular notch. The condyle is usually displaced anteromedially (because exposures may be extended to gain access to the anterior and middle
of the attachment of lateral pterygoid to the temporomandibular joint cranial fossae, cavernous sinus, clivus, craniocervical junction and upper
disc, capsule and anterior border of the neck of the condyle). Nowadays, cervical vertebrae.
most condylar fractures are managed by open reduction and early A variety of different access osteotomies have been described and
mobilization. found to be useful in specific clinical situations. Most of the osteot
Angle of mandible omies described follow the conventional patterns of facial fractures
described above. The entire hemimaxilla and zygoma can be mobilized,
The majority of fractures of the mandible run posteriorly and inferiorly
and pedicled on the soft tissues of the face by making bone cuts that
from the alveolar bone to the angle. The presence of a third molar tooth
follow the lines of a Le Fort II fracture on one side. The osteotomy is
produces a line of weakness, and a fracture line will pass through its
completed by dividing the upper alveolus and palate just to the side of
socket. The unopposed pull of the powerful elevator muscles (masseter,
the nasal septum and perpendicular plate of the vomer. The maxilla
medial pterygoid and temporalis) will typically displace the posterior
may be mobilized at the Le Fort I level and downfractured, pedicled
fragment superiorly, anteriorly and medially.
on the palatoglossal muscles and soft tissue attachments. This gives


Ramus and coronoid process good access to the nasopharynx, clivus and upper cervical spine, par
Fractures at the ramus exhibit very little displacement as a consequence ticularly if the palate is divided in the midline.
of the splinting activity of medial pterygoid medially and masseter lat Lateral zygomatic osteotomies may be performed to gain access to
erally, the pterygomasseteric sling; their wide attachments to the ramus the orbital apex and infratemporal fossa. The surgical approach is from
extend across the fracture lines. Similarly, the coronoid process is rarely behind using a hemi or bicoronal flap. The zygomatic complex is
displaced significantly because it is splinted by the tendinous insertion mobilized inferiorly, pedicled on masseter. When combined with a
of temporalis. mandibular ramus osteotomy, access is gained to the retromaxillary area
and pterygoid space as well as to the infratemporal fossa. In combin
Body of mandible
ation with a frontotemporal craniotomy, the zygomatic osteotomy has
Most fractures of the body of the mandible occur as the result of direct been used for access to the middle cranial fossa, cavernous sinus, apex
trauma and tend to be concentrated in the first molar or canine region. of the petrous temporal bone and the interpeduncular cistern.
The more anterior the site of the fracture, the more the upward displace Dividing the lower lip in the midline, and dividing the mandible
ment of the elevators is counteracted by the downward pull of genio either in the midline or just in front of the mental foramen, allows the
hyoid and the anterior belly of digastric. When teeth are present, hemimandible to be swung laterally. The technique is used to give
displacement is limited by the dental occlusion (i.e. further displace improved access to the floor of the mouth, the base of the tongue,
ment is resisted by the lower and upper teeth), whereas displacement tonsillar fossa, soft palate, oropharynx, posterior pharyngeal wall,
may be considerable in an edentulous patient. supraglottic larynx and pterygomandibular region. By extending the


dissection laterally, access is gained to the pterygoid space, infratempo
Campbell’s lines
ral fossa and parapharyngeal space. By dissecting more medially, access
is gained to the nasopharynx, lower part of the clivus and all seven of
Campbell’s lines are five lines that are systematically traced when assess the cervical vertebrae. A modification of the mandibular swing proce
ing maxillofacial radiographs. Line 1 joins the two zygomaticofrontal dure increases access up to the skull base, by combining the classic
sutures; it runs along the superior orbital margins and crosses the mandibular swing with a horizontal osteotomy of the mandibular
midline in the region of the glabella. Line 2 runs along the zygomatic ramus above the level of the lingula.
bone and the inferior orbital margin, crosses the frontal process of the
maxilla and lateral wall of the nose, and then passes through the nasal
MUSCLES OF THE FACE
septum to follow a similar course to the contralateral zygomatic bone.
Line 3 begins at the condyle of the mandible, passes across the man
dibular notch and coronoid process of the mandible, then crosses the Craniofacial muscles are associated with the orbital margins and eyelids,
maxillary sinus from its lateral to medial walls and continues through external nose and nostrils, lips, cheeks and mouth, pinna, scalp and
the lateral wall of the nose at the level of the nasal floor; it follows a cervical skin, and collectively are often called, not very accurately,
similar course on the contralateral side. Line 4 follows the occlusal ‘muscles of facial expression’ (Fig. 30.17). Their organization differs
plane of the upper and lower teeth, and line 5 follows the lower border from that of muscles in most other regions of the body because there
of the mandible. is no deep membranous fascia beneath the skin of the face, and many
small slips of muscle that are attached to the facial skeleton insert
Cranial base
directly into the skin.
Although these muscles produce movements of the facial skin that
The cranial base – clinically regarded as, the frontal, ethmoid, sphenoid reflect emotions, it is usually argued that their primary function is to


and occipital bones – is a relatively solid platform inclined at an angle act as sphincters and dilators of the facial orifices and that the function
of 45° to the maxillary occlusal plane. Fractures of the cranial base are of facial expression has developed secondarily. Embryologically, they
not readily visible on normal radiographs and are best detected on CT are derived from the mesenchyme of the second branchial arch and so
scans. They result in bleeding in the floor of the middle cranial fossa, are innervated by the facial nerve. Topographically and functionally, the
which often presents as bruising over the mastoid process (Battle’s muscles of facial expression may be subdivided into epicranial, circum
sign). These fractures may be associated with dural tears and escape of orbital and palpebral, nasal, and buccolabial groups (Fig. 30.18).


Face and scalp
489.e1
03
ReTpaHc
A B
Fig. 30.16 A, A typical large medial wall and floor fracture. The bone here,
the lamina papyracea, is the thinnest in the orbit. The intact medial wall
on the right side is outlined in green. B, In this case, the intact right
medial wall (green line) was mirrored; the red line outlines the defect
on the left orbit. C, A titanium plate was then placed through a
C transconjunctival incision, with lateral cantholysis; the position was
checked with intraoperative navigation.


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REFERENCES
Ahmas F, Kirkpatrick NA, Lyne J et al 2006 Buckling and hydraulic mecha Le Fort R 1901 Etude expérimental sur les fractures de la mâchoire supérieure.
nisms in orbital blowout fractures: fact or fiction. J Craniofac Surg Rec Chir Paris 23:208–27.
17:438–41. A paper that represents the standard way of describing maxillary fractures.
A paper that does for orbital injuries what Le Fort did for maxillary injuries. Le Fort’s classification has endured and still resonates in clinical practice.
The contribution of anatomy to the pathogenesis of floor and medial orbital
Lineaweaver W, Rhoton A, Habal MB 1997 Microsurgical anatomy of the
fractures is elegantly shown.
facial nerve. Craniofac Surg 8:6–10.
Borges AF, Alexander JE 1962 Relaxed skin tension lines, Zplasties on scars, Loukota RA, Eckelt U, De Bont L et al 2005 Subclassification of fractures of
and fusiform excision of lesions. Br J Plast Surg 15:242–54. the condylar process of the mandible. Br J Oral Maxillofac Surg 43:
A paper that provides the anatomical basis for every incision made on the 72–3.
face. A very brief paper that is superb in its simplicity, presenting a logical and
Davis RA, Anson BJ, Budinger JM et al 1956 Surgical anatomy of the facial pragmatic approach to classifying these injuries, and signposting both
nerve and parotid gland based upon a study of 350 cervicofacial halves. surgical difficulty and approach.
Surg Gynecol Obstet 102:385–412. Manson PN, Grivas A, Rosenbaum A et al 1986 Studies on enophthalmos:
Eljamel M, Foy P 1990 Posttraumatic CSF fistulae: the case for surgical II. The measurement of orbital injuries and their treatment by quantita
repair. Br J Neurosurg 4:479–83. tive computed tomography. Plast Reconstr Surg 77:203–14.
A paper that provides the clinical evidence for management of fractures of Markowitz B, Manson PN, Sargent L et al 1991 Management of the medial


the anterior skull base. canthal tendon in nasoethmoid fractures: the importance of the central
Ellis E 3rd, Tan Y 2003 Assessment of internal orbital reconstructions for fragment in classification and treatment. Plast Reconstr Surg 87:
pure blowout fractures: cranial bone versus titanium mesh. J Oral Maxil 843–5.
lofac Surg 61:442–53. Mihailovic T, Stimec BV, Terzic M et al 2012 The absence of the vomer in
Farkas LG, Posnick JC, Hreczko TM et al 1992 Growth patterns of the the first and early second trimester of pregnancy – a new marker of
nasolabial region: a morphometric study. Cleft Palate Craniofac J 29: trisomy 21 and trisomy 13. Ultraschall Med 33:E68–74.
318–24. Mitz V, Peyronie M 1976 The superficial musculoaponeurotic system
Ferrario VF, Sforza C, Schmitz JH et al 2000 Normal growth and develop (SMAS) in the parotid and cheek area. Plast Reconstruct Surg 58:
ment of the lips: a 3dimensional study from 6 years to adulthood using 80–8.
a geometric model. J Anat 196:415–23. A paper that provides the anatomical basis for all invasive aesthetic and
reconstructive facelift surgery.
Fromer J 1977 The human accessory parotid gland: its incidence, nature and
significance. Oral Surg Oral Med Oral Pathol 43:671–6. Shimada K, Gasser RF 1988 Morphology of the mandibulostylohyoid liga
Gillies HD, Kilner TP, Stone D 1927 Fractures of the malar–zygomatic com ment in human adults. Anat Rec 222:207–10.
pound: with a description of a new Xray position. Br J Surg 14:651–6. Wassef M 1987 Superficial fascial and muscular layers in the face and neck:
An old paper but the technique described is a very practical application of a histological study. Aesth Plast Surg 11:171–6.