Download Palatine Bones

Chapter 8
Lecture Outline
8-1
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The Skeletal System
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Parietal bone
Frontal bone
• overview of the skeleton
Skull
• the vertebral column and
thoracic cage
Mandible
Mandible
Pectoral
girdle
• the skull
Maxilla
Clavicle
Scapula
Sternum
Thoracic
cage
Humerus
Ribs
Costal cartilages
Vertebral column
Pelvis
Hip bone
Sacrum
Ulna
Radius
Coccyx
Carpus
Metacarpal
bones
Phalanges
• the pectoral girdle and
upper limb
Femur
Patella
Fibula
• the pelvic girdle and
lower limb
Tibia
Metatarsal bones
Tarsus
Phalanges
(a) Anterior view
Figure 8.1a
8-2
Overview of the Skeleton
• two regions of the skeleton
– axial skeleton – forms the central supporting axis of the body
• skull, auditory ossicles, hyoid bone, vertebral column, and thoracic
cage (ribs and sternum)
– appendicular skeleton – includes the bones of the upper limb
and pectoral girdle, and the bones of the lower limb and pelvic
girdle
• number of bones
– 206 in typical adult skeleton
• varies with development of sesamoid bones (patella)
– bones that form within some tendons in response to stress
• varies with presence of sutural (wormian) bones in skull
– extra bones that develop in skull suture lines
– 270 bones at birth, decreases with fusion
• surface markings defined in Table 8.2
– ridges, spines, bumps, depressions, canals, pores, slits, cavities,
8-3
and articular surfaces
Axial and Appendicular Skeleton
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Parietal bone
Frontal bone
Skull
Pectoral
girdle
Occipital bone
Maxilla
Mandible
Mandible
Clavicle
Clavicle
Scapula
Scapula
• axial skeleton is
colored tan
– skull, vertebrae,
sternum, ribs, sacrum
and hyoid
Sternum
Humerus
Thoracic Ribs
cage
Costal cartilages
Vertebral column
Pelvis
Hip bone
Sacrum
• appendicular
skeleton is colored
green
Ulna
Radius
Coccyx
Carpus
Metacarpal
bones
Phalanges
–
–
–
–
Femur
Patella
Fibula
Tibia
pectoral girdle
upper extremity
pelvic girdle
lower extremity
Metatarsal bones
Tarsus
Phalanges
(a) Anterior view
Figure 8.1
(b) Posterior view
8-4
Anatomical Features of Bones
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Lines
Crest
Sinuses
Foramen
Fovea
Head
Meatus
Crest
Trochanters
Process
Condyle
Spine
Head
Tubercle
Alveolus
Foramen
Tuberosity
(a) Skull (lateral view)
Line
Process
Fossae
Spine
Epicondyles
Fossae
Condyles
(b) Scapula (posterior view)
Figure 8.2
(c) Femur
(posterior view)
(d) Humerus
(anterior view)
8-5
The Skull
• skull – the most complex part of the skeleton
• 22 bones joined together by sutures (immovable joints)
• 8 cranial bones surround cranial cavity which encloses the brain
• other cavities – orbits, nasal cavity, oral (buccal) cavity, middle-,
and inner ear cavities, and paranasal sinuses
• paranasal sinuses – frontal, sphenoid, ethmoid, and maxillary
– lined by mucous membrane and air-filled
– lighten the anterior portion of the skull
– act as chambers that add resonance to the voice
• foramina – holes that allow passage for nerves and blood vessels
• 14 facial bones support teeth, facial and jaw muscles
8-6
Major Skull Cavities
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Cranial cavity
Ethmoid
air cells
Frontal bone
Ethmoid bone
Orbit
Superior
Nasal
conchae
Middle
Zygomatic
bone
Inferior
Maxilla
Maxillary
sinus
Vomer
Nasal cavity
Oral
cavity
Mandible
Figure 8.7
8-7
Cranial Fossa
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Figure 8.9
Frontal lobe
Anterior cranial
fossa
Temporal lobe
Middle cranial
fossa
Cerebellum
Posterior cranial
fossa
Posterior cranial fossa
Middle cranial fossa
Anterior cranial fossa
•
•
(a) Superior view
(b) Lateral view
cranium (braincase) – protects the brain and associated sense organs
– swelling of the brain inside the rigid cranium may force tissue through
foramen magnum resulting in death
– consists of two parts: the calvaria (skullcap) and the cranial base
base is divided into three basins that comprise the cranial floor
8-8
Frontal Bone
• forms forehead and part of
the roof of the cranium
• coronal suture – posterior
boundary of frontal bone
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Frontal bone
Glabella
Coronal suture
Supraorbital
foramen
Parietal bone
Supraorbital
margin
• supraorbital foramen
provides passage for nerve,
artery, and vein
Squamous suture
Lacrimal bone
Ethmoid bone
Nasal bone
Middle nasal
concha
Zygomatic bone
Infraorbital foramen
Vomer
• contains frontal sinus
Temporal bone
Sphenoid bone
Inferior nasal
concha
Maxilla
Mandible
Mental protuberance
Mental foramen
Figure 8.3
8-9
Parietal Bone
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Coronal suture
Frontal bone
Parietal bone
Temporal lines
Lambdoid suture
Ethmoid bone
Sphenoid bone
Nasal bone
Occipital bone
Lacrimal bone
Squamous suture
• form most of cranial roof
and part of its lateral
walls
Zygomaticofacial foramen
Temporal bone
Infraorbital foramen
Zygomatic process
External acoustic meatus
Zygomatic bone
Maxilla
Mastoid process
Temporal process
Styloid process
Mandible
Mandibular condyle
Mental foramen
(a) Right lateral view
Figure 8.4a
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Anterior
Frontal bone
Coronal suture
Parietal bone
Sagittal suture
• bordered by 4 sutures
– sagittal – between parietal
bones
– coronal – at anterior
margin
– lambdoid – at posterior
margin
– squamous – at lateral
border
Sutural bone
Parietal foramen
Lambdoid suture
Occipital bone
Posterior
Figure 8.6
8-10
Temporal
Bone
• lateral wall and part of floor
of cranial cavity
– squamous part
• zygomatic process
• mandibular fossa
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Coronal suture
Frontal bone
Parietal bone
Temporal lines
Lambdoid suture
Ethmoid bone
Sphenoid bone
Nasal bone
Occipital bone
– tympanic part
• external auditory meatus
• styloid process
Lacrimal bone
Squamous suture
Zygomaticofacial foramen
Temporal bone
Infraorbital foramen
Zygomatic process
External acoustic meatus
Zygomatic bone
Maxilla
Mastoid process
Temporal process
Styloid process
Mandible
Mandibular condyle
Mental foramen
(a) Right lateral view
Figure 8.4a
– mastoid part
• mastoid process
– mastoiditis from ear
infection
• stylomastoid foramen
• mastoid foramen
8-11
Petrous Portion of Temporal Bone
– petrous part
• part of cranial floor
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Diploe (spongy bone)
Frontal bone
Crista galli
Cribriform plate
of ethmoid bone
Cribriform foramina
• houses middle and inner ear
cavities
Sphenoid bone
Optic foramen
Sella turcica
Foramen rotundum
Foramen ovale
Temporal bone
Foramen spinosum
Internal acoustic
meatus
• receptors for hearing and
sense of balance
Petrous part of
temporal bone
Jugular foramen
Parietal bone
Groove for
venous sinus
Foramen magnum
Occipital bone
Hypoglossal canal
(b) Superior view of cranial floor
Figure 8.5b
• internal auditory meatus
- opening for CN VII
(vestibulocochlear nerve)
• carotid canal
• jugular foramen
8-12
Occipital Bone
• rear and base of skull
• foramen magnum holds spinal
cord
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Incisive foramen
Palatine process
of maxilla
Intermaxillary suture
Zygomatic bone
• skull rests on atlas at occipital
condyles
• hypoglossal canal transmits
hypoglossal nerve (CN XII)
supplying tongue muscles
Palatine bone
Zygomatic arch
Greater palatine foramen
Posterior nasal
aperture
Medial pterygoid plate
Lateral pterygoid plate
Vomer
Sphenoid bone
Foramen ovale
Mandibular fossa
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Styloid process
External acoustic meatus
Occipital condyle
Stylomastoid foramen
Mastoid process
Mastoid notch
Temporal bone
Jugular foramen
Foramen magnum
Condylar canal
Mastoid foramen
Parietal bone
Lambdoid suture
Inferior nuchal line
External occipital
protuberance
Superior nuchal line
Occipital bone
(a) Inferior view
Figure 8.5a
8-13
Sphenoid Bone
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Lesser wing
Dorsum sellae
Greater wing
Superior orbital
fissure
Foramen
rotundum
Body
Foramen ovale
Lateral pterygoid plate
Medial pterygoid plate
Pterygoid processes
(b) Posterior view
Figure 8.11b
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• body
• greater wing
• lesser wing
• optic foramen
Diploe (spongy bone)
Frontal bone
Cribriform plate
of ethmoid bone
Crista galli
Cribriform foramina
Sphenoid bone
Optic foramen
Foramen rotundum
Foramen ovale
Foramen spinosum
Internal acoustic
meatus
Jugular foramen
Sella turcica
Temporal bone
Petrous part of
temporal bone
Parietal bone
Foramen magnum
Groove for
venous sinus
Hypoglossal canal
Occipital bone
(b) Superior view of cranial floor
Figure 8.5b
8-14
Sphenoid Bone
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Coronal suture
Frontal bone
Incisive foramen
Parietal bone
Palatine process
of maxilla
Sphenoid sinus
Squamous suture
Frontal sinus
Intermaxillary suture
Zygomatic bone
Crista galli
Palatine bone
Zygomatic arch
Cribriform plate of
ethmoid bone
Posterior nasal
aperture
Perpendicular plate
of ethmoid bone
Vomer
Occipital bone
Temporal bone
Sella turcica
Lambdoid suture
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
Styloid process
Mandibular foramen
Greater palatine foramen
Medial pterygoid plate
Lateral pterygoid plate
Nasal bone
Sphenoid bone
Foramen ovale
Vomer
Mandibular fossa
Palatine process
of maxilla
Styloid process
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Maxilla
External acoustic meatus
Occipital condyle
(b) Median section
Stylomastoid foramen
Palatine bone
Mandible
Mastoid process
Mastoid notch
Mental spines
Temporal bone
Jugular foramen
Foramen magnum
Condylar canal
Mastoid foramen
Parietal bone
Lambdoid suture
Inferior nuchal line
Figure 8.4b
External occipital
protuberance
Superior nuchal line
Occipital bone
(a) Inferior view
Figure 8.5a
sphenoid sinus
8-15
Ethmoid Bone
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• between the eyes
Supraorbital foramen
Roof of
orbit
Orbital plate of frontal bone
Lesser wing of sphenoid bone
Greater wing of
sphenoid bone
Optic foramen
Orbital plate of ethmoid bone
Medial
wall
Lacrimal bone
Lateral wall
of orbit
Orbital surface of
zygomatic bone
• contributes to medial wall
of orbit
Superior orbital fissure
Frontal process of maxilla
Orbital process of
palatine bone
Floor of
orbit
Zygomatic process
of frontal bone
Inferior orbital
fissure
Infraorbital
foramen
Orbital surface of
maxilla
Figure 8.14
• lateral walls and roof of
nasal cavity, and nasal
septum
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Cribriform
plate
Cribriform
foramina
Orbital plate
Ethmoidal
cells
Perpendicular
plate
Crista galli
• cribriform plate – forms
roof of nasal cavity
Superior
nasal concha
Middle
nasal concha
– ethmoid cells in the
make up ethmoid
sinuses
Figure 8.12
8-16
Ethmoid Bone
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Coronal suture
Frontal bone
Crista galli
Parietal bone
Frontal bone
Cribriform plate
Sphenoid sinus
Frontal sinus
Cribriform foramina
Squamous suture
Frontal sinus
Nasal bone
Sella turcica
Crista galli
Nasal conchae:
Occipital bone
Temporal bone
Sella turcica
Lambdoid suture
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
Cribriform plate of
ethmoid bone
Superior
Perpendicular plate Sphenoid sinus
of ethmoid bone
Inferior
Nasal bone
Middle
Nasal cartilages
Occipital bone
Vomer
Palatine process
of maxilla
Styloid process
Mandibular foramen
Maxilla
Palatine bone
Mandible
Mental spines
(b) Median section
Sphenoid bone
Anterior nasal spine
Palatine bone
Incisive foramen
Lacrimal bone
Lip
Maxilla
Incisor
Figure 8.4b
Figure 8.13
superior and middle concha
perpendicular plate of nasal septum
8-17
Facial Bones
• facial bones (14)– those that have no direct contact with
the brain or meninges
–
–
–
–
support the teeth
give shape and individuality to the face
form part of the orbital and nasal cavities
provide attachments for muscles of facial expression and
mastication
2 maxillae
2 palatine bones
2 zygomatic bones
2 lacrimal bones
2 nasal bones
2 inferior nasal conchae
1 vomer
1 mandible
8-18
Maxillary Bones
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Frontal bone
• largest facial bones
• forms upper jaw and meet each
other at a median intermaxillary
suture
• forms inferomedial wall of orbit
– infraorbital foramen
– inferior orbital fissure
• forms most of the hard palate
– palatine process
– palate – forms the roof of the
mouth and floor of nasal cavity
– incisive foramen
– palate allows us to chew while
breathing
– cleft palate and cleft lip
Supraorbital
foramen
Glabella
Parietal bone
Coronal suture
Supraorbital
margin
Squamous suture
Temporal bone
Sphenoid bone
Lacrimal bone
Ethmoid bone
Nasal bone
Middle nasal
concha
Zygomatic bone
Inferior nasal
concha
Infraorbital foramen
Maxilla
Vomer
Figure 8.3
Mandible
Mental foramen
Mental protuberance
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Incisive foramen
Palatine process
of maxilla
Zygomatic bone
Intermaxillary suture
Zygomatic arch
Palatine bone
Greater palatine foramen
Medial pterygoid plate
Lateral pterygoid plate
Posterior nasal
aperture
Vomer
Sphenoid bone
Mandibular fossa
Foramen ovale
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Stylomastoid foramen
Jugular foramen
Foramen magnum
Mastoid foramen
Styloid process
External acoustic meatus
Occipital condyle
Mastoid process
Mastoid notch
Temporal bone
Condylar canal
Parietal bone
Lambdoid suture
Inferior nuchal line
External occipital
protuberance
Superior nuchal line
Occipital bone
Figure 8.5a
(a) Inferior view
8-19
Location of Maxillary Sinus
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Sphenoid
sinus
Frontal
sinus
Ethmoid
sinus
Maxillary
sinus
FigureFigure
8.8 8.8
• maxillary sinus fills maxillae bone
• larger in volume than frontal, sphenoid
and ethmoid sinuses
8-20
Palatine Bones
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• L-shaped bone
Crista galli
Frontal bone
Cribriform plate
• form the posterior portion
of the hard palate
Frontal sinus
Cribriform foramina
Nasal bone
Sella turcica
Nasal conchae:
Superior
Middle
Sphenoid sinus
Inferior
Nasal cartilages
Occipital bone
• part of lateral nasal cavity
wall
Sphenoid bone
Anterior nasal spine
Palatine bone
Incisive foramen
Lacrimal bone
Lip
Maxilla
Incisor
Figure 8.13
• part of the orbital floor
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Supraorbital foramen
• greater palatine
foramina
Roof of
orbit
Orbital plate of frontal bone
Lesser wing of sphenoid bone
Zygomatic process
of frontal bone
Greater wing of
sphenoid bone
Optic foramen
Orbital surface of
zygomatic bone
Orbital plate of ethmoid bone
Medial
wall
Lacrimal bone
Superior orbital fissure
Frontal process of maxilla
Inferior orbital
fissure
Orbital process of
palatine bone
Floor of
orbit
Lateral wall
of orbit
Infraorbital
foramen
Orbital surface of
maxilla
Figure 8.14
8-21
Zygomatic Bones
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Coronal suture
Frontal bone
Parietal bone
Temporal lines
Lambdoid suture
Ethmoid bone
Sphenoid bone
Nasal bone
Occipital bone
Lacrimal bone
Squamous suture
Zygomaticofacial foramen
Temporal bone
• forms angles of the
cheekbones and part of
lateral orbital wall
• zygomaticofacial
foramen
Infraorbital foramen
Zygomatic process
External acoustic meatus
Zygomatic bone
Maxilla
Mastoid process
Temporal process
Styloid process
Mandible
Mandibular condyle
Mental foramen
(a) Right lateral view
Figure 8.4a
• zygomatic arch is
formed from temporal
process of zygomatic
bone and zygomatic
process of temporal
bone
8-22
Lacrimal Bones
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Coronal suture
Frontal bone
Parietal bone
Temporal lines
Lambdoid suture
Ethmoid bone
Sphenoid bone
• form part of medial wall of
each orbit
• smallest bone of skull
Nasal bone
Occipital bone
Lacrimal bone
Squamous suture
Zygomaticofacial foramen
Temporal bone
Infraorbital foramen
Zygomatic process
External acoustic meatus
Zygomatic bone
Maxilla
Mastoid process
Temporal process
Styloid process
Mandible
Mandibular condyle
Mental foramen
(a) Right lateral view
• lacrimal fossa houses
lacrimal sac in life
– tears collect in lacrimal sac
and drain into nasal cavity
Figure 8.4a
8-23
Nasal Bones
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• forms bridge of nose
Frontal bone
Glabella
Coronal suture
• supports cartilages
that shape lower
portion of the nose
• often fractured by
blow to the nose
Supraorbital
foramen
Parietal bone
Supraorbital
margin
Squamous suture
Temporal bone
Sphenoid bone
Lacrimal bone
Ethmoid bone
Nasal bone
Middle nasal
concha
Zygomatic bone
Infraorbital foramen
Vomer
Inferior nasal
concha
Maxilla
Mandible
Mental protuberance
Mental foramen
Figure 8.3
8-24
Vomer
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Coronal suture
Frontal bone
Parietal bone
Sphenoid sinus
Squamous suture
Frontal sinus
Crista galli
Occipital bone
Cribriform plate of
ethmoid bone
Temporal bone
Sella turcica
Lambdoid suture
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
Perpendicular plate
of ethmoid bone
Nasal bone
Vomer
Palatine process
of maxilla
Styloid process
Mandibular foramen
• inferior half of the
nasal septum
– superior half formed
by perpendicular plate
of ethmoid
Maxilla
Palatine bone
Mandible
Mental spines
(b) Median section
Figure 8.4b
• supports cartilage that
forms the anterior part
of the nasal septum
8-25
Mandible
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•
•
•
•
•
•
•
•
strongest bone of the skull
only bone of skull that moves noticeably
supports lower teeth
provides attachments for muscles of
facial expression and mastication
mental symphysis – median
cartilaginous joint in fetus
– develops as two separate bones in
fetus
– ossifies in early childhood
mental protuberance – point of chin
two major parts on each side
– body – supports teeth
– ramus – articulates with cranium
mental foramen
Figure 8.5a
Incisive foramen
Palatine process
of maxilla
Intermaxillary suture
Zygomatic bone
Palatine bone
Zygomatic arch
Greater palatine foramen
Posterior nasal
aperture
Medial pterygoid plate
Lateral pterygoid plate
Vomer
Sphenoid bone
Foramen ovale
Mandibular fossa
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Styloid process
External acoustic meatus
Occipital condyle
Stylomastoid foramen
Mastoid process
Mastoid notch
Temporal bone
Jugular foramen
Foramen magnum
Condylar canal
Mastoid foramen
Parietal bone
Lambdoid suture
Inferior nuchal line
External occipital
protuberance
Superior nuchal line
Occipital bone
(a) Inferior view
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Mandibular condyles
Condylar process
Coronoid process
Mandibular notch
Mandibular foramen
Ramus
Alveolar process
Mental foramen
Mental protuberance
Figure 8.15
Angle
Body
8-26
Ramus, Angle and Body of
Mandible
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Mandibular condyles
Condylar process
Coronoid process
Mandibular notch
Mandibular foramen
Ramus
Alveolar process
Mental foramen
Mental protuberance
Angle
Body
• condylar process bears the
mandibular condyle – oval knob
that articulates with the mandibular
fossa of the temporal bone forming
the hinge temporomandibular
joint (TMJ)
• coronoid process – point of
insertion of temporalis muscle
• mandibular notch
Figure 8.15 • mandibular foramen
8-27
Bones Associated With Skull
• auditory ossicles
– three in each middle-ear cavity
– malleus, incus, and stapes
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• hyoid bone
– slender u-shaped bone
between the chin and larynx
– does not articulate with any
other bone
– suspended from styloid
process of skull by muscle and
ligament
– body and greater and lesser
horns (cornua)
– fractured hyoid bone is
evidence of strangulation
Styloid process
Stylohyoid muscle
Hyoid
Larynx
Lesser horn
Greater horn
Body
Figure 8.16
8-28
Skull in Infancy and Childhood
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Coronal
suture
Frontal
bone
Parietal bone
• fontanels - spaces between
unfused bones
– filled with fibrous membrane
– allow shifting of bones during
birth and growth of brain
– anterior, posterior, sphenoid
(anterolateral), and mastoid
(posterolateral fontanels
Sphenoid
fontanel
Lambdoid
suture
Nasal
bone
Squamous
suture
Maxilla
Occipital bone
Zygomatic
bone
Mastoid
fontanel
Temporal bone
Mandible
Sphenoid
bone
(a) Lateral view
• two frontal bones fuse by age
6 (metopic suture)
Frontal bone
Anterior fontanel
Sagittal suture
• skull reaches adult size by 8
or 9 years of age
Parietal
bone
Posterior fontanel
(b) Superior view
Figure 8.17
8-29
The Vertebral Column (Spine)
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•
•
functions
– supports the skull and trunk
– allows for their movement
– protects the spinal cord
– absorbs stress of walking, running,
and lifting
– provides attachments for limbs
thoracic cage, and postural muscles
Anterior view
Posterior view
Atlas (C1)
Axis (C2)
Cervical vertebrae
C7
T1
Thoracic vertebrae
33 vertebrae with intervertebral discs
of fibrocartilage between most of them
T12
•
adult vertebral column averages 71 cm.
(28 in.) long
– intervertebral discs account for about
one-quarter of its length
– person is 1% shorter when they go to
bed
– compression squeezes water out
during the day and absorbs water
when compression removed during
sleep
L1
Lumbar vertebrae
L5
S1
Sacrum
S5
Coccyx
Figure 8.18
Coccyx
8-30
The Vertebral Column (Spine)
• five vertebral groups
– 7 cervical in the neck
– 12 thoracic in the
chest
– 5 lumbar in lower back
– 5 fused sacral at base
of spine
– 4 fused coccygeal
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Anterior view
Posterior view
Atlas (C1)
Axis (C2)
Cervical vertebrae
C7
T1
Thoracic vertebrae
T12
L1
• variations in number of
lumbar and sacral
vertebrae occur in 1 in
20 people
Lumbar vertebrae
L5
S1
Sacrum
S5
Coccyx
Figure 8.18
Coccyx
8-31
Adult Spinal Curvatures
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C1
Cervical curvature
C7
T1
Thoracic curvature
• s-shaped vertebral column with
four normal curvatures
–
–
–
–
cervical
thoracic
lumbar
pelvic
• primary curvatures – present at
birth
– thoracic and pelvic
T12
L1
Lumbar curvature
L5
S1
Pelvic curvature
Figure 8.19
• secondary curvatures – develop
later
– cervical and lumbar
– lifting head as it begins to crawl
develops cervical curvature
– walking upright develops lumbar
curvature
8-32
Abnormal Spinal Curvatures
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•
from disease, paralysis of trunk
muscles, poor posture, pregnancy, or
congenital defect
•
scoliosis – abnormal lateral curvature
–
–
–
–
•
(a) Scoliosis
Key
Normal
Pathological
(b) Kyphosis
(“hunchback”)
(c) Lordosis
(“hunchback”)
most common
usually in thoracic region
particularly of adolescent girls
developmental abnormality in which
the body and arch fail to develop on
one side of the vertebrae
kyphosis (hunchback) – exaggerated
thoracic curvature
– usually from osteoporosis, also
osteomalacia or spinal tuberculosis, or
wrestling or weightlifting in young boys
Figure 8.21
•
lordosis (swayback) – exaggerated
lumbar curvature
–
is from pregnancy or obesity
8-33
General Structure of Vertebra
• body (centrum)
– mass of spongy bone that
contains red bone marrow
– covered with thin shell of
compact bone
– weight bearing portion
• vertebral foramina
– collectively form vertebral
canal for spinal cord
• spinous process
– projection extending from the
apex of arch
– extends posteriorly and
downward
• transverse process
– extends laterally from point
where pedicel and lamina
meet
• processes from the vertebra
above
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Posterior
Spinous process
Lamina
Superior articular
facet
Vertebral
arch
Transverse
process
Pedicle
Vertebral foramen
Body
Anterior
(a) 2nd lumbar vertebra (L2)
Nucleus pulposus
Anulus fibrosus
(b) Intervertebral disc
Figure 8.22
8-34
Intervertebral Foramen and Discs
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Superior articular
process of L1
Inferior vertebral
notch of L1
L1
Intervertebral
foramen
Superior vertebral
notch of L2
L2
Spinous process
Intervertebral disc
L3
Inferior articular
process of L3
(b) Left lateral view
Figure 8.23b
• intervertebral foramen
– passageway for spinal nerves
• intervertebral discs (23)
– first one between C2 and C3
– last one between L5 and
sacrum
– pad bind vertebrae together
– support weight of the body
– absorb shock
– herniated disc (‘ruptured’ or
‘slipped’ disc) puts painful
pressure on spinal nerve or
spinal cord
8-35
Cervical Vertebra C1 - Atlas
• atlas (C1)
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Transverse
process
Body (centrum)
– supports the head
– has no body
• allows nodding motion of
skull gesturing ‘yes’
L2
Intervertebral disc
Inferior articular
process of L2
Superior articular
process of L3
Lamina
Figure 8.23a
L3
(a) Posterior (dorsal) view
8-36
Cervical Vertebra C2 - Axis
• axis (C2)
– allows rotation of the
head gesturing ‘no’
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Dens (odontoid process)
Body
Superior articular facet
Transverse foramen
Transverse process
Pedicle
Inferior articular process
Lamina
Spinous process
(b) Axis
Figure 8.24b
8-37
Sacrum (Anterior View)
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Superior articular
process
Sacral
promontory
Ala
S1
S2
Transverse lines
S3
Anterior sacral
foramina
S4
S5
Coccyx
Co2 Co1
Co3
Co4
(a) Anterior view
• sacrum – bony plate that forms
the posterior wall of the pelvic
cavity
• once considered the seat of the
soul
• in children, five separate sacral
vertebrae (S1 – S5)
• begin fusion around age 16 and
complete fusion by age 26
• anterior surface
– 4 pair of large anterior sacral
(pelvic) foramina
• allow for passage of
nerves and arteries into
the pelvic organs
Figure 8.26a
8-38
Coccyx
• coccyx – usually consists of
four small vertebrae (Co1 –
Co4)
Sacral canal
– sometimes five
• fuse into a single, triangular
Median
sacral crest
bone by age 20 – 30
Auricular
• fractured during difficult
surface
Lateral sacral
childbirth or by hard fall on
crest
buttocks
Posterior sacral
foramina
• provide attachment for
Sacral hiatus
muscles of the pelvic floor
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Superior articular
process
Horn
Transverse
process
Coccyx
Figure 8.26b
(b) Posterior view
8-39
Thoracic Cage
•
consists of thoracic vertebrae,
sternum and ribs
•
forms conical enclosure for
lungs and heart
•
provides attachment for pectoral
girdle and upper limbs
•
broad base and narrower apex
•
rhythmically expanded by
respiratory muscles to draw air
into the lungs
•
costal margin – inferior border
of thoracic cage formed by the
downward arc of ribs
•
protect thoracic organs, but
also the spleen, most of the
liver, and to some extent the
kidneys
8-40
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Sternoclavicular joint
Sternum:
Acromioclavicular joint
T1
1
Pectoral girdle:
Clavicle
Scapula
Suprasternal notch
Clavicular notch
Manubrium
2
Angle
3
Body
4
True ribs (1–7)
5
Xiphoid process
6
7
Costal cartilages
11
8
False ribs (8–12)
Floating ribs
(11–12)
12
9
10
T12
L1
Costal margin
Figure 8.27
Sternum
• sternum (breastbone) – bony plate anterior to the heart
• divided into three regions:
– Manubrium
– body (gladiolus)
• longest part of sternum
• sternal angle – point where body joins manubrium
• ribs attach along scalloped lateral margins
– xiphoid
• inferior end of sternum
• attachment for some of abdominal muscles
• in cardiopulmonary resuscitation, improperly performed chest
compressions can drive xiphoid process into the liver and cause
a fatal hemorrhage
8-41
Ribs
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Tubercle
Neck
Head
Superior Inferior
Angle
Articular facet
for transverse
process
Articular facets
for vertebral bodies
Costal groove
Shaft
Figure 8.28b
(b) Ribs 2–10
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Superior
articular
facet
Transverse
costal facet
for rib 6
• 12 pairs of ribs
– no difference between
sexes
– posterior (proximal)
end attached to vertebral
column
– anterior (distal) ends
mostly attached to the
sternum
– costal cartilages
composed of hyaline
cartilage attach anterior
ends to sternum
Tubercle
Superior
costal
facet
for rib 6
Neck
T6
(b) Superior view
Rib 6
Head
Figure 8.29b
8-42
True and False Ribs
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Sternoclavicular joint
Sternum:
Acromioclavicular joint
T1
1
Pectoral girdle:
Clavicle
Scapula
Suprasternal notch
Clavicular notch
Manubrium
2
Angle
3
Body
4
True ribs (1–7)
5
Xiphoid process
6
7
Costal cartilages
11
8
False ribs (8–12)
Floating ribs
(11–12)
12
9
10
T12
L1
Costal margin
Figure 8.27
• true ribs (ribs 1 to 7)
– each has its own costal
cartilage connecting it to
the sternum
• false ribs (ribs 8-12)
– lack independent
cartilaginous connection to
the sternum
– floating ribs (ribs 11 – 12)
• articulate with bodies of
vertebrae T11 and T12
• no cartilaginous
connection to the
sternum or any of the
higher costal
cartilages
8-43
Pectoral Girdle
• pectoral girdle (shoulder girdle) – supports the
arm
• consists of two bones on each side of the body
– clavicle (collarbone) and scapula (shoulder blade)
• clavicle articulates medially to the sternum and
laterally to the scapula
– sternoclavicular joint
– acromioclavicular joint
• scapula articulates with the humerus
– glenohumeral joint - shoulder joint
– easily dislocated due to loose attachment
8-44
Clavicle
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Sternal
end
Acromial
end
Conoid tubercle
(a) Superior view
Figure 8.30
Conoid tubercle
Sternal
end
Acromial
end
(b) Inferior view
•
•
•
•
•
clavicle - S-shaped, somewhat flattened bone
sternal end - rounded head
acromial end – flattened
braces the shoulder keeping upper limb away from the midline of the body
most frequently fractured bone in the body
8-45
Scapula
• scapula – named for its resemblance to a spade or shovel
• suprascapular notch – conspicuous notch on superior border
– provides passage for a nerve
• spine – transverse ridge on posterior surface
• complex lateral angle of scapula has three main features:
– acromion – platelike extension of the spine
– coracoid process – shaped like a bent finger
– glenoid cavity – shallow socket that articulates with the head of the
humerus
8-46
Scapula
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Superior
border
Suprascapular
notch
Superior angle
Acromion
Acromion
Supraspinous
fossa
Coracoid
process
Glenoid
cavity
Lateral
angle
Spine
Subscapular
fossa
Infraspinous
fossa
Lateral
border
Medial
border
Inferior angle
(a) Anterior view
(b) Posterior view
Figure 8.31
8-47
Upper Limb
• upper limb is divided into four regions containing a
total of 30 bones per limb
– brachium (arm proper) – extends from shoulder to elbow
• contains only one bone - humerus
– antebrachium (forearm) – extends from elbow to wrist
• contains two bones - radius and ulna
– carpus (wrist)
• contains 8 small bones arranged in 2 rows
– manus (hand)
• 19 bones in 2 groups
– 5 metacarpals in palm
– 14 phalanges in fingers
8-48
Humerus
• proximal end
– hemispherical head that
articulates with the glenoid
cavity of scapula
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Greater
tubercle
Head
Lesser
tubercle
Greater
tubercle
Anatomical
neck
Surgical
neck
Intertubercular
sulcus
• distal end
Nutrient
foramen
Deltoid
tuberosity
Deltoid
tuberosity
Figure 8.32
– rounded capitulum
articulates with head of radius
– trochlea articulates with ulna
– lateral and medial
epicondyles
– olecranon fossa holds
olecranon process of ulna
– coronoid fossa
– radial fossa
Coronoid
fossa
Radial
fossa
Lateral
epicondyle
Capitulum
Medial
supracondylar
ridge
Medial
epicondyle
Trochlea
(a) Anterior view
Lateral
supracondylar
ridge
Lateral
epicondyle
Olecranon
fossa
(b) Posterior view
8-49
Radius
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Olecranon
Olecranon
Trochlear notch
Radial notch
of ulna
Head of
radius
Neck of
radius
Head of
radius
Coronoid process
• radius
Neck of
radius
Ulnar tuberosity
Radial
tuberosity
Ulna
• superior surface articulates with
capitulum on humerus
• side of disc spins on radial
notch on ulna
Radius
Interosseous
borders
Interosseous
membrane
Ulnar notch
of radius
Head of ulna
Styloid process
Styloid
process
Styloid
process
Articular facets
(a) Anterior view
– head – disc-shape, allows for
rotation around the longitudinal
axis of the bone during pronation
and supination of hand
– neck
– radial tuberosity for biceps
muscle
– styloid process can be palpated
near thumb
– ulnar notch
(b) Posterior view
Figure 8.33
8-50
Ulna and Interosseous Membrane
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Olecranon
Olecranon
Trochlear notch
Radial notch
of ulna
Head of
radius
Neck of
radius
Head of
radius
Coronoid process
Neck of
radius
Ulnar tuberosity
Radial
tuberosity
Ulna
Radius
Interosseous
borders
Ulnar notch
of radius
Head of ulna
Styloid process
Styloid
process
Articular facets
(a) Anterior view
– trochlear notch articulates
with trochlea of humerus
– olecranon – bony point at
back of elbow
– coronoid process
– radial notch holds head of
radius
– styloid process
• interosseous membrane
Interosseous
membrane
Styloid
process
• ulna
– ligament attaches radius to
ulna along interosseous
margin of each bone
– enables the two elbow joints
to share the load
(b) Posterior view
Figure 8.33
8-51
Carpal Bones
• 8 bones form wrist
– allow movements of
flexion, extension,
abduction and adduction
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Distal phalanx II
Middle phalanx II
Key to carpal bones
Distal row
• 2 rows (4 bones each)
Proximal row
Proximal phalanx II
IV
Head
Phalanges
Body
III
Distal
phalanx I
II
V
Base
I
Proximal
phalanx I
Head
Metacarpal Body
bones
Base
Carpal
bones
First
metacarpal
Hamulus of hamate
Hamate
Pisiform
Triquetrum
Lunate
(a) Anterior view
Figure 8.34a
Trapezoid
Trapezium
Carpal
Capitate
bones
Scaphoid
– proximal row –
– scaphoid, lunate,
triquetrum, and
pisiform
• pisiform is a sesamoid
developed by age 9
to12 in tendon of flexor
carpi ulnaris muscle
– distal row trapezium, trapezoid,
capitate, and hamate
8-52
Metacarpals and Phalanges
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Distal phalanx II
Middle phalanx II
Proximal phalanx II
IV
Head
Phalanges
Body
III
• metacarpals - bones of the
palm
– metacarpal I proximal to
Key to carpal bones
Distal row
base of thumb
Proximal row
– metacarpal V proximal to
base of little finger
Distal
phalanx I
II
V
Base
I
Proximal
phalanx I
Head
Metacarpal Body
bones
Base
Carpal
bones
First
metacarpal
Hamulus of hamate
Hamate
Pisiform
Triquetrum
Lunate
(a) Anterior view
Trapezoid
Trapezium
Carpal
Capitate
bones
Scaphoid
• phalanges - bones of the
fingers
– thumb or pollex has two
phalanges
fingers have three
phalanges
Figure 8.34a
8-53
•
pelvic girdle – consists of a
complete ring composed of three
bones
– two hip (coxal) bones
– sacrum that is also part of the
vertebral column
Pelvic Girdle
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pelvis – bowl-shaped structure
composed of the two coxal bones
and sacrum
supports trunk on the lower limbs
and protects viscera, lower colon,
urinary bladder, and internal
reproductive organs
Iliac
crest
•
Iliac
fossa
•
sacroiliac joint - joins hipbone to
the vertebral column
pubic symphysis – the interpubic
disc and adjacent regions of the
pubic bone on each side
Sacroiliac joint
Anterior
superior
iliac spine
Pelvic surface
of sacrum
Anterior inferior
iliac spine
Pelvic inlet
Spine
Coccyx
Acetabulum
Ischium
Body
Interpubic
disc
Ramus
Pubis
•
Base of
sacrum
Ilium
Obturator
foramen
Superior ramus
Inferior ramus
Body
Pubic symphysis
(a) Anterosuperior view
Figure 8.35a
8-54
Hip Bone
•
•
three distinct features of hip bone
– iliac crest – superior crest of hip
– acetabulum – the hip socket
– obturator foramen – large hole
below acetabulum
each adult hip bone is formed by the
fusion of three childhood bones
– ileum
• the largest
• extends from the iliac crest to
the center of the acetabulum
– ischium
• inferioposterior portion of hip
• heavy body with prominent
spine
– pubis (pubic bone)
• most anterior portion of the hip
bone
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Ilium
Ischium
Pubis
Iliac crest
Anterior gluteal
line
Inferior gluteal
line
Anterior superior
iliac spine
Posterior gluteal
line
Posterior superior
Iliac spine
Posterior inferior
Iliac spine
Anterior
r
inferior
iliac spine
Greater sciatic notch
Body of ilium
Acetabulum
Superior ramus
of pubis
Ischial spine
Body of pubis
Lesser sciatic notch
Body of ischium
Inferior ramus
of pubis
Ischial tuberosity
Obturator foramen
Ramus of ischium
(a) Lateral view
Figure 8.36a
8-55
Comparison of Male and Female
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Male
Female
Pelvic brim
Pelvic inlet
Obturator foramen
Pubic arch
90
120
Figure 8.37
• male - heavier and thicker due to forces exerted by
stronger muscles
• female - wider and shallower, and adapted to the needs of
pregnancy and childbirth, larger pelvic inlet and outlet for
passage of infant’s head
8-56
Lower Limb
• lower limb divided into four regions containing
30 bones per limb
– femoral region (thigh) – extends from hip to knee
region
• contains the femur and patella
– crural region (leg proper) – extends from knee to
ankle
• contains medial tibia and lateral fibula
– tarsal region (tarsus) – ankle – the union of the crural
region with the foot
• tarsal bones are considered part of the foot
– pedal region (pes) - foot
• composed of 7 tarsal bones, 5 metatarsals, and 14
phalanges in the toes
8-57
Femur
• longest and strongest bone of the
body
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Fovea capitis
Greater trochanter
Greater trochanter
Head
Neck
Intertrochanteric crest
Intertrochanteric line
Lesser trochanter
Spiral line
Gluteal tuberosity
Linea aspera
Shaft
Medial supracondylar line
Lateral supracondylar
line
Popliteal surface
Lateral epicondyle
Medial epicondyle
• hemispherical head that
articulates with the acetabulum of
the pelvis
– forms ball-and-socket joint
– fovea capitis – pit in head of
femur for attachment of a
ligament
• greater and lesser trochanters
for muscle attachment
Lateral epicondyle
Patellar surface
Lateral condyle
Intercondylar fossa
Medial condyle
Base of patella
Articular facets
• medial and lateral condyles and
epicondyles found distally
Apex of patella
(a) Anterior view
Figure 8.38
(b) Posterior view
• patellar and popliteal surface
8-58
Patella (Kneecap)
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Fovea capitis
Greater trochanter
Greater trochanter
Head
Neck
Intertrochanteric crest
Intertrochanteric line
Lesser trochanter
Spiral line
Gluteal tuberosity
Linea aspera
Shaft
• patella - triangular
sesamoid bone embedded
in tendon of the knee
• cartilaginous at birth
– ossifies at 3 to 6 year
• quadriceps femoris tendon
extends from the anterior
muscle of the thigh to the
patella
– continues as the patellar
ligament from the patella to the
tibia
Medial supracondylar line
Lateral supracondylar
line
Popliteal surface
Lateral epicondyle
Medial epicondyle
Lateral epicondyle
Patellar surface
Lateral condyle
Intercondylar fossa
Medial condyle
Base of patella
Articular facets
Apex of patella
(a) Anterior view
Figure 8.38
(b) Posterior view
8-59
Tibia
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Intercondylar eminence
Medial
condyle
Lateral condyle
Apex
Head of fibula
Tibial
tuberosity
Proximal tibiofibular
joint
Interosseous
membrane
Lateral surface
Anterior crest
Tibia
Fibula
• tibia - thick, medial, weightbearing bone
– only weight bearing bone of
the crural region
– broad superior head
– medial and lateral
condyles
• fairly flat articular
surfaces
• articulate with condyle
of femur
– medial malleolus – bony
knob on inside of ankle
Distal tibiofibular joint
Medial
malleolus
Lateral malleolus
(a) Anterior view
Figure 8.39
Lateral malleolus
(b) Posterior view
8-60
Fibula
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Intercondylar eminence
Medial
condyle
Lateral condyle
Apex
Head of fibula
Tibial
tuberosity
Proximal tibiofibular
joint
• fibula – slender, lateral
strut that helps stabilizes
ankle
• does not bear any body
weight
Interosseous
membrane
Lateral surface
– spare bone tissue for grafts
Anterior crest
• head - proximal end
Tibia
• apex – point of the head
Fibula
• lateral malleolus - distal
expansion, bony knob on
lateral side of ankle
Distal tibiofibular joint
Medial
malleolus
Lateral malleolus
(a) Anterior view
Figure 8.39
Lateral malleolus
(b) Posterior view
• joined to tibia by
interosseous membrane
8-61
The Ankle and Foot
• tarsal bones – arranged in
proximal and distal groups
• tarsal bones are shaped and
arranged differently from carpal
bones due to load-bearing role of
the ankle
• calcaneus – largest tarsal bone
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Distal phalanx I
Distal
phalanx V
Proximal phalanx I
Middle
phalanx V
I
II
– forms heel
– distal portion is point of attachment
for calcaneal (Achilles) tendon
Proximal
phalanx V
Metatarsal
III
IV
V
• talus is most superior tarsal bone
Medial cuneiform
Intermediate cuneiform
Lateral cuneiform
Navicular
Cuboid
Talus
Calcaneus
Trochlear surface
of talus
Key to tarsal bones
Distal
group
Tuberosity of calcaneus
(a) Superior (dorsal) view
Proximal group
– forms ankle joint with tibia and
fibula
– sits upon calcaneus and articulates
with navicular
• proximal row of tarsal bones
– talus, calcaneus, and navicular
• distal row of tarsal bones
Figure 8.40a
– medial, intermediate and lateral
cuneiforms and cuboid
8-62
The Foot
• remaining bones of foot are
similar in name and
arrangement to the hand
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• metatarsals
Distal phalanx I
– metatarsal I is proximal to the
great toe (hallux)
– metatarsal V is proximal to the
little toe
– proximal base, intermediate
shaft, and distal head
Distal
phalanx V
Proximal phalanx I
Middle
phalanx V
Proximal
phalanx V
Metatarsal
I
II
III
IV
V
Medial cuneiform
Intermediate cuneiform
Lateral cuneiform
Navicular
Cuboid
Talus
• phalanges
Calcaneus
Trochlear surface
of talus
Key to tarsal bones
Distal
group
Tuberosity of calcaneus
(a) Superior (dorsal) view
Proximal group
– 2 in great toe
• proximal and distal phalanx
– 3 in all other toes
• proximal, middle and distal
phalanx
Figure 8.40a
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Embryonic Limb Rotation
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Thumb
Future
thumb
Elbow
Knee
Future
great toe
(a) Seven weeks
Great toe
(b) Eight weeks
Figure 8.41
• rotation of upper and lower limbs in opposite directions
–
–
–
–
starts seventh week of embryonic development
largest digit medial in foot and lateral in hand
each limb rotates about 90° in opposite directions
rotation also explains why elbow flexes posteriorly and knee flexes
8-64
anteriorly
Foot Arches
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Medial
longitudinal arch
Transverse
arch
Lateral
longitudinal
arch
(a) Inferior (plantar) view
– sole of foot is not flat on ground
– 3 springy arches absorb stress
• medial longitudinal arch
– from heel to hallux
– formed from the calcaneus,
talus,
• lateral longitudinal arch
– from heel to little toe
• transverse arch
– across middle of foot
– arches held together by short, strong
ligaments
• pes planus (flat feet) –
excessive weight, repetitious
stress, or congenital weakness
Figure 8.42a
8-65
Skeletal Adaptations for Bipedalism
• humans are only animals habitually bipedal
– 3.6 million year old human footprints indicate upright
walking
• adaptations
– strong, springy foot arches
– great toe not opposable
– femurs angle inward so knees are closer together –
erect posture requires less muscular effort
– viscera supported in bowl-shaped pelvis
– insertions of gluteal muscles differ from other
primates
8-66
Bipedalism and Limb Adaptations
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
(a) Foot
(b) Knee
Chimpanzee
Human
Figure 8.43(1)a,b
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Chimpanzee
Human
Bipedalism and Upright Stance
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
(c) Gluteal muscles
Chimpanzee
(d) Pelvis
(e) Vertebral column
Chimpanzee
Chimpanzee
Human
Figure 8.43(1)c
Human
Figure 8.43(2)d,e
Human
8-68
Bipedalism and Head Position
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
(f) Skull
Supraorbital
ridge
Pivot
Foramen
magnum
Chimpanzee
Pivot
Figure 8.43(2)f
Foramen
magnum
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Human