cranium, the skull i

CRANIUM
THE SKULL
R. Druga
Institute of Anatomy, 2nd and 1st Medical
Faculty
NEUROCRANIUM
SPLANCHNOCRANIUM
CRANIUM, THE SKULL I

Most highly modified region in the axial
skeleton
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The neurocranium – developed from a
series of cartilages ventral to the brain (base)
From mesenchyme over the dome of the
head (calvaria or calva)
Cranial cavity
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Splanchnocranium – branchial apparatus
(cartilaginous elements) have been replaced
by overlying dermal bones
Branchial apparatus
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The mandibular region and the neck are
formed by six paired branchial arches
(cart. bars supporting the gill apparatus).
In the tetrapods branchial arches were
modified and persist in the facial (maxilla,
mandibula) and neck skeleton (laryngeal
cartilages)
Derivatives of
cartilagines of
the branchial
arches
1st arch =
Meckel
cart., mandibula,
malleus
2nd arch = Reichert
cart., stapes, styloid
proc.,stylohyoid lig.
3rd arch = hyoid
bone
4th and 6th arch =
laryngeal cartil.
CRANIUM II
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Complex of skeletal elements, adapted to
support and contain the brain, brain vessels,
cranial nerves and envelops
Special senses (eye ball, nasal cavity, inner ear)
Intracranial spaces (epidural, subdural,
subarachnoideal)
Circulating cerebrospinal fluid
x
CRANIUM
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Komplex kostí axiálního skeletu
Obsahuje mozek, mozkové cévy a obaly
Obsahuje oční kouli a sluchový aparát
Člení se na bazi lební, kalvu
(calvaria) a na obličejový skelet.
Pro klinickou medicinu má největší
význam baze lební a obličejový
skelet !!
CRANIUM III
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General cranial features
Base
Calvaria
Facial skeleton
Spaces, cavities
The skull, considered as a whole, is of greater
practical importance than the individual bones of
which it is made up !!!!!! Most important part of
the skull is the
base.
Norma lateralis
Norma
facialis
or
Norma
frontalis
The orbit
The
anterior
nasal
aperture
The interior of the
cranium
Basis cranii
interna
Norma
basalis
Basis cranii
externa
The anterior,
middle and
posterior
cranial fossa
Basis cranii
interna
Fossae cranii
!
OS
OCCIPITALE
Squamous, basilar and
lateral part
Internal aspect
Cruciate eminence, 4 fossae
Occipital bone of a newborn child
Posterior aspect
Inferior aspect
OS
SPHENOIDALE
In the base of
the skull
Resembles a
bird with wings
outstretched
Body
The
greater
wings
The
lesser
wings
The
pterygoid
processes
Posterior
aspect
Chiasmatic sulcus
– optic cana
Superior
aspect
Hypophyseal
fossa
Dorsum sellae
Sella turcica
Sulcus caroticus
Sphenoid bone – body
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Cubical, contains two air sinuses /
septum
Anteriorly – ethmoid bone
Posteriorly – occipital bone
Sulcus chiasmatis (optic canal)
Hypophyseal fossa + Dorsum sellae=
sella turcica (Turkish saddle)
Fissura orbitalis
superior :
III., IV., VI.,
V/1,
V. orbitalis sup.
For. rotundum :
V/2
For. ovale : V/3
For. spinosum:
a. meningea
media
ANTERIOR ASPECT
Greater wing – 5 surfaces (facies)
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Cerebral surface – part of the midle cranial fossa
Orbital surface – part of the lateral wall of the orbit
Temporal surface – temporal fossa
Infratemporal surface- infratemporal fossa
Sphenomaxillar surface- pterygopalatine fossa
OS
TEMPORALE
Parts:
Squamous
Petromastoid
Tympanic
(styloid process)
Petrous part of the temporal bone
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Is wedged between the sphenoid and occipital
bones
Has a base, an apex, four surfaces, three margins
The anterior (superior) surface (trigeminal impression,
arcuate eminence)
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The posterior surface (the internal acoustic meatus)
The inferior surface (the carotid canal, the jugular fossa)
The ventrobasal surface (medial wall of the tympanic
cavity)
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x
OS TEMPORALE – PARS PETROSA,
PYRAMIS
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Klínovitá konfigurace- mezi os sphenoidale a
occipitale
Base, apex, 4 stěny (facies)
Facies posterior (porus acusticus internus)
Facies inferior (canalis caroticus, fossa jugularis)
Facies anterior (eminentia arcuata, impressio
trigeminalis)
Facies ventrobasalis (= mediální stěna cavum
tympani)
Temporal bone + pyramis – external aspect
PYRAMIS-internal
aspect (facies ant. et
post.)
Internal acoustic meatus - n. VII., n.VIII.)
Porus and meatus acusticus internus
Meatus acusticus
internus l. dx.
PYRAMIS,
FACIES
INFERIOR
Carotid canal
Stylomastoid
foramen (n. VII.)
Jugular foramen
(internal jugular
vein, N. IX., X.,
XI.)
Canaliculus for
the tympanic
nerve
Jugular
foramen
Facies inferior
Canalis caroticus
Foramen jugulare
Processus styloideus
Foramen
Stylomastoideum
Processus
mastoideus
Fossa mandibularis
Canaliculus
tympanicus
PYRAMIS : FACIES VENTROBASALIS
Medial wall of the tympanic cavity
Mastoid
air cells
Celullae
mastoideae
Pneumatic
type
Stylomastoid foramen.
Canalis n. facialis
Tympanic cavity
Promontory
Tympanic nerve –
Tympanic plexus
Tympanic
cavity,
posterior wall
N. VII.
Mastoid antrum
(3,5)
External auditory
meatus (1)
Pyramidal
eminence
Chorda tympani
Tympanic sulcus
Pyramid - canals and spaces
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Canalis nervi facialis – meatus ac. internus – for.
Stylomastoideum (3 parts :ventrolateral, dorsolateral, caudal)
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Canalis caroticus – facies inferior – apex pyramidis
Canaliculus tympanicus – fossula petrosa – cavum tympani –
sulcus promontorii
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Canaliculus chordae tympani – canalis n. facialis –
cavum tympani – fissura petrotympanica
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Canalis musculotubarius – m. tensor tympani, Eustachian tube
Labyrinthus osseus – vestibulum, canales semicirculares, cochlea
OS FRONTALE, SQUAMA FRONTALIS, PARTES ORBITALES
Desmogenní osifikace
ze dvou základů
Inferior aspect
Roof of
the orbit
OS FRONTALE, PARTES ORBITALES, PARS
NASALIS (Apertura sinus frontalis)
Internal aspect
SQUAMA FRONTALIS
OS ETHMOIDALE
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Lamina cribrosa (nerve I.)
Lamina perpendicularis (crista galli)
Labyrithi ethmoidales (cellulae
ethmoidales)
Lamina orbitalis (papyracea)
Concha nasalis media et superior
Cock´ s comb
Parietal
bone
Sulci of the middle meningeal
artery
Epidural space
Epidural hematoma
OBLIČEJOVÝ
SKELET
FACIAL
SKELETON
Maxilla
4 plochy
4 surfaces
Tělo + 4
výběžky:
Body + 4
processes
(proc.
frontalis,
palatinus,
zygomaticus
(/apex),
alveolaris)
Maxillary
sinus (25 cm3)
Facies :
anterior,
posterior,
orbitalis
nasalis (the base
of the hollow
pyramidal body)
Maxillary hiatus is
ovelaid by ethmoid
conchae
Maxilla - ossification
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The maxilla ossifies in membrane.
The premaxilla (incisive bone, carrying incisor
teeth) is in most mammals an independent
bone.
OSSA PALATINA
OSSA
PALATINA
Orbital process (3)
Sphenoidal process
(5)
Sphenopalatine
incisure
MANDIBULA
CORPUS +
Corpus –
Alveolar process
RAMUS –
Condylar
process
(articular
surface)
Coronoid
process
(temporalis m.)
Each half
ossifies from a
single centre in
membrane
ovelying the
Meckel
cartilage
Sublingual fossa
Submandibular fossa
Mandibular canal
Ramus in line with the body
Age changes in the mandible
Following the loss of
teeth the alveolar part is
absorbed
THE
NASAL
CAVITY
THE
ORBITAL
CAVITY
CAVITAS
NASI
OSSEA
ORBITA
Piriform
aperture –
Choanae
Facies lateralis
CAVUM
NASI
THE NASAL
CAVITY,
FRONTAL
SECTION
CAVUM
NASI
MEATUS
NASI :
inferior
medius
superior
SINUS
PARANASALES
Frontal
Maxillary
Ethmoidal
Sphenoidal
THE ORBIT
ORBITA
THE ORBIT, MEDIAL WALL
ORBITA, FACIES MEDIALIS
Temporal fossa
FOSSA
TEMPORALIS,
Infratemporal
fossa
INFRATEMPO
RALIS
Pterygomandibular
fissure
Infratemporal
fossa :
Lamina lateralis
proc. Pterygoidei and
maxilla – mandibular
ramus
FOSSA
PTERYGOPALATINA
Pterygomandibular
fissura
Rotundum
Upper wall :
maxillary surface of
the greater wings
Pterygoid canal
Sphenopalatine for.
Inferior orbital
fissure
Medial wall:
palatine bone
Greater palatine canal
Anterior wall :
maxilla
Posterior wall :
pterygoid process
FOSSAE
CRANII
Anterior
Middle
Posterior
Lebka novorozence
Lebka
Skull in a new-born
Facial part small
(rudimentary condition
of the mandible and
maxillae)
Ossification is
incomplete
Paranasal
sinuses - absent
6 fontanellae
Anterior fontanelle
BREGMA
Posterior fontanelle
The skull during the birth
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The skull is altered in shape
The skull is compressed and elongated
Bones of cranial vault (calva) overlap to a
small extent (fontanellae !!)
These changes disappear within a week
x
Konfigurace lebky při porodu
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Lebka je komprimována (mediolaterálně)
Elongace lebky
Kosti kalvy se podsouvají (fontanely)
V průběhu několika dnů se konfigurace
lebky vrací k nornálu
CRANIOMETRY
Frankfurt plane
Frankfurtská
horizontála
gnathion
CRANIOMETRY I

Cranial height = bregma – basion = Výška lebky

Cranial breadth = euryon – euryon = Šířka lebky

Cranial length = glabella - occipital point = Délka lebky
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Facial height = nasion – gnathion = Výška obličeje
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Facial breadth = zygion - zygion = Šířka obličeje
CRANIOMETRY
CRANIAL INDEX
Š x 100/ d
do 75 dolicho75 – 80 meso-
Breadth x 100/
length
Up to 75
dolichocephalic
75 – 80
mesocephalic
80 – 85
brachycephalic
80 a více brachy -
Sexual differences
Female : wall thinner, superciliary arches, tuberosities and mastoid
processes less prominent, air sinuses smaller, tubera frontalia at
parietalia +
References :
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R. Čihák : Anatomie 1, Avicenum
M. Grim, R. Druga et al.: Základy anatomie. Galen 2001
Gray ´s Anatomy, Longman 1973
P. Kopf – Maier : Atlas of Human Anatomy, Karger, 1990
KONEC LEBKY