Download The Skeletal System

The Skeletal System
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Parietal bone
Frontal bone
• overview of the skeleton
Skull
• the vertebral column and
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
thoracic cage
Metacarpal
bones
Phalanges
Femur
• the pectoral girdle and
upper limb
• the pelvic girdle and
lower limb
Patella
Fibula
Tibia
Metatarsal bones
Tarsus
Phalanges
(a) Anterior view
Figure 8.1a
8-1
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
8-2
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)
8-4
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
8-5
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
Mandible
Oral
cavity
Figure 8.7
8-6
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
•
base is divided into three basins that comprise the cranial floor
– anterior cranial fossa holds the frontal lobe of the brain
– middle cranial fossa holds the temporal lobes of the brain
– posterior cranial fossa contains the cerebellum
8-7
Frontal Bone
• forms forehead and part of
the roof of the cranium
• coronal suture – posterior
boundary of frontal bone
• contains frontal sinus
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Frontal bone
Glabella
Coronal suture
Squamous suture
Supraorbital
foramen
Parietal bone
Supraorbital
margin
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
8-8
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
8-9
Temporal
Bone
• lateral wall and part of floor
of cranial cavity
– squamous part
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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
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
• encircled by squamous
suture
• zygomatic process
• mandibular fossa
– tympanic part
• external auditory meatus
• styloid process
– mastoid part
• mastoid process
8-10
Temporal Bone
– part of cranial floor
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Diploe (spongy bone)
Frontal bone
Crista galli
• separates middle from
posterior cranial fossa
Cribriform plate
of ethmoid bone
Cribriform foramina
Sphenoid bone
Optic foramen
Sella turcica
Foramen rotundum
• houses middle and inner ear
cavities
Foramen ovale
Temporal bone
Foramen spinosum
Internal acoustic
meatus
Petrous part of
temporal bone
Jugular foramen
Parietal bone
Groove for
venous sinus
Foramen magnum
• internal auditory meatus
Occipital bone
Hypoglossal canal
(b) Superior view of cranial floor
Figure 8.5b
8-11
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
Palatine bone
Zygomatic arch
• skull rests on atlas at occipital
condyles
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
8-12
Sphenoid Bone
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Lesser wing
Dorsum sellae
Greater wing
Superior orbital
fissure
Foramen
rotundum
Body
Foramen ovale
• optic foramen
Lateral pterygoid plate
Medial pterygoid plate
Pterygoid processes
(b) Posterior view
Figure 8.11b
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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
8-13
Sphenoid Bone
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Optic foramen
Hypophyseal fossa
Lesser wing
Greater wing
Foramen rotundum
Sella turcica
Anterior clinoid
process
Foramen ovale
Foramen spinosum
Dorsum sellae
(a) Superior view
Figure 8.11a
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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
Figure 8.5b
(b) Superior view of cranial floor
8-14
Sphenoid Bone
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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
Sphenoid bone
Foramen ovale
Mandibular fossa
Palatine process
of maxilla
Styloid process
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Maxilla
(b) Median section
Lateral pterygoid plate
Vomer
Nasal bone
Styloid process
Mandibular foramen
Greater palatine foramen
Medial pterygoid plate
External acoustic meatus
Occipital condyle
Palatine bone
Mandible
Mastoid process
Mastoid notch
Mental spines
Temporal bone
Stylomastoid foramen
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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Supraorbital foramen
Roof of
orbit
Lesser wing of sphenoid bone
Zygomatic process
of frontal bone
Greater wing of
sphenoid bone
Orbital plate of ethmoid bone
Floor of
orbit
between the eyes
•
contributes to medial wall of orbit
•
lateral walls and roof of nasal
cavity, and nasal septum
Orbital plate of frontal bone
Optic foramen
Medial
wall
•
Lacrimal bone
Lateral wall
of orbit
Orbital surface of
zygomatic bone
Superior orbital fissure
Frontal process of maxilla
Orbital process of
palatine bone
Inferior orbital
fissure
Infraorbital
foramen
Orbital surface of
maxilla
Figure 8.14
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Cribriform
plate
Cribriform
foramina
Orbital plate
Ethmoidal
cells
Perpendicular
plate
Figure 8.12
Crista galli
Superior
nasal concha
Middle
nasal concha
8-16
Ethmoid Bone
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Coronal suture
Frontal bone
Parietal bone
Crista galli
Cribriform plate
Sphenoid sinus
Cribriform foramina
Squamous suture
Frontal sinus
Frontal bone
Frontal sinus
Nasal bone
Sella turcica
Crista galli
Nasal conchae:
Occipital bone
Superior
Cribriform plate of
ethmoid bone
Temporal bone
Sella turcica
Lambdoid suture
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
Middle
Perpendicular plate Sphenoid sinus
of ethmoid bone
Nasal bone
Inferior
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 nasal bones
2 palatine bones
2 inferior nasal conchae
2 zygomatic bones
1 vomer
2 lacrimal bones
1 mandible
8-18
Maxillary Bones
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Frontal bone
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
Styloid process
External acoustic meatus
Occipital condyle
Mastoid process
Mastoid notch
Temporal bone
Condylar canal
Foramen ovale
Foramen spinosum
Foramen lacerum
Basilar part of
occipital bone
Carotid canal
Stylomastoid foramen
Jugular foramen
Foramen magnum
Mastoid foramen
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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• form the posterior portion
of the hard palate
Crista galli
Frontal bone
Cribriform plate
Frontal sinus
Cribriform foramina
Nasal bone
Sella turcica
Nasal conchae:
Superior
Middle
Sphenoid sinus
Inferior
Nasal cartilages
Occipital bone
Sphenoid bone
Anterior nasal spine
Palatine bone
Incisive foramen
Lacrimal bone
Lip
Maxilla
Incisor
Figure 8.13
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Supraorbital foramen
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
Floor of
orbit
Lateral wall
of orbit
Lacrimal bone
Superior orbital fissure
Frontal process of maxilla
Inferior orbital
fissure
Orbital process of
palatine bone
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
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
• forms angles of the
cheekbones and part of
lateral orbital wall
• 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
Nasal bone
Occipital bone
• form part of medial wall of
each orbit
• smallest bone of skull
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
Squamous suture
Supraorbital
foramen
Parietal bone
Supraorbital
margin
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
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
• 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
Mental protuberance
Angle
Body
Figure 8.15
8-27
Bones Associated With Skull
• auditory ossicles
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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
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
– filled with fibrous membrane
– allow shifting of bones during
birth and growth of brain
Sphenoid
fontanel
Lambdoid
suture
Nasal
bone
Squamous
suture
Maxilla
Occipital bone
Zygomatic
bone
Mastoid
fontanel
Temporal bone
• fontanels - spaces between
unfused bones
Mandible
Sphenoid
bone
(a) Lateral view
Frontal bone
• two frontal bones fuse by age
6
• skull reaches adult size by 8
or 9 years of age
Anterior fontanel
Sagittal suture
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
33 vertebrae with intervertebral discs
of fibrocartilage between most of them
Anterior view
Posterior view
Atlas (C1)
Axis (C2)
Cervical vertebrae
C7
T1
Thoracic vertebrae
T12
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
Lumbar vertebrae
L5
S1
Sacrum
S5
Coccyx
Figure 8.18
Coccyx
8-31
General Structure of Vertebra
•
body (centrum)
–
–
•
vertebral foramina
–
•
Posterior
Spinous process
Lamina
Superior articular
facet
Vertebral
arch
Transverse
process
Pedicle
Vertebral foramen
Body
extends laterally
superior articular processes
–
•
projection extending from the apex of arch
extends posteriorly and downward
transverse process
–
•
collectively form vertebral canal for spinal
cord
spinous process
–
–
•
weight bearing portion
rough superior and inferior surfaces provide
firm attachment for intervertebral discs
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project upward from one vertebra and
meets inferior articular processes from
the vertebra above
Anterior
(a) 2nd lumbar vertebra (L2)
facets
–
flat articular surfaces covered with hyaline
cartilage
Nucleus pulposus
Anulus fibrosus
(b) Intervertebral disc
Figure 8.22
8-32
Intervertebral Foramen and Discs
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intervertebral foramen
–
Superior articular
process of L1
•
Inferior vertebral
notch of L1
L1
•
Intervertebral
foramen
Superior vertebral
notch of L2
L2
Spinous process
passageway for spinal nerves
intervertebral discs (23)
–
–
–
–
–
–
first one between C2 and C3
last one between L5 and sacrum
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
Intervertebral disc
L3
Inferior articular
process of L3
(b) Left lateral view
Figure 8.23b
8-33
Cervical Vertebra C1 + C2
atlas (C1)



articulates with occipital condyles
allows nodding motion of skull gesturing ‘yes’
axis (C2)


allows rotation of the head gesturing ‘no’
8-34
Cervical Vertebra C2 - Axis
• axis (C2)
– allows rotation of the head gesturing ‘no’
8-35
Atlas and Axis Articulation
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Axis of rotation
Dens
Atlas
Transverse
ligament
Figure 8.24c
Axis
(c) Atlantoaxial joint
8-36
Sacrum and Coccyx
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Superior articular
process
Sacral
promontory
Ala
S1
S2
sacrum – bony plate that forms the
posterior wall of the pelvic cavity
in children, five separate sacral
vertebrae
coccyx – usually consists of four
sometimes five, fuse into a single,
triangular bone by age 20 – 30
Transverse lines
S3
Anterior sacral
foramina
S4
S5
Coccyx
Co2 Co1
Co3
Co4
(a) Anterior view
Figure 8.26a
8-37
Thoracic Cage
•
consists of thoracic vertebrae,
sternum and ribs
•
provides attachment for pectoral
girdle and upper limbs
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)
9
10
12
T12
L1
Costal margin
Figure 8.27
8-38
Sternum
• sternum (breastbone) – bony plate anterior to the heart
• divided into three regions:
– Manubrium
– body
– xiphoid
8-39
Articulation of Rib 6 with
Vertebrae T5 and T6
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Inferior costal
facet of T5
Vertebral
body T5
Superior articular
facet of rib 6
Vertebral
body T6
Inferior articular
facet of rib 6
Superior costal
facet of T6
Rib 6
(a) Anterior view
Superior
articular
facet
Transverse
costal facet
for rib 6
Tubercle
Figure 8.29
Superior
costal
facet
for rib 6
T6
Neck
Head
Rib 6
8-40
(b) Superior view
True and False Ribs
• true ribs (ribs 1 to 7)
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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
– 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)
11
8
False ribs (8–12)
Floating ribs
(11–12)
9
10
12
T12
L1
Costal margin
Figure 8.27
8-41
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
• scapula articulates with the humerus
– glenohumeral joint - shoulder joint
8-42
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
inferior – grooves and ridges for muscle attachment
sternal end - rounded head
acromial end – flattened
• braces the shoulder keeping upper limb away from the midline of the body
8-43
Scapula
• scapula
• lateral angle of scapula has three main features:
– acromion
• forms apex of the shoulder
• articulates with the clavicle
– coracoid process
• provides attachment for tendons of the biceps brachii and other arm muscles
– glenoid cavity – shallow socket that articulates with the head of the humerus
• forming glenohumeral joint
8-44
Scapula
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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
8-45
Upper Limb
• Humerus
• Radius and ulna
• Carpal bones (wrist)
• 5 metacarpals in palm
• 14 phalanges in fingers
8-46
Humerus
• proximal end
– hemispherical head that
articulates with the glenoid
cavity of scapula
– greater and lesser tubercles
and deltoid tuberosity
– intertubercular sulcus holds
biceps tendon
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Greater
tubercle
Greater
tubercle
Head
Lesser
tubercle
Anatomical
neck
Surgical
neck
Intertubercular
sulcus
Nutrient
foramen
Deltoid
tuberosity
Deltoid
tuberosity
• distal end
Figure 8.32
Coronoid
fossa
Radial
fossa
Lateral
epicondyle
Capitulum
Medial
supracondylar
ridge
Medial
epicondyle
Trochlea
(a) Anterior view
– rounded capitulum
articulates with head of radius
– trochlea articulates with ulna
– lateral and medial
epicondyles
– olecranon fossa holds
olecranon process of ulna
Lateral
supracondylar
ridge
Lateral
epicondyle
Olecranon
fossa
(b) Posterior view
8-47
Radius
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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
– radial tuberosity for biceps
muscle
– styloid process can be palpated
near thumb
– ulnar notch
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
(b) Posterior view
Figure 8.33
8-48
Ulna and Interosseous Membrane
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Olecranon
Olecranon
Trochlear notch
Radial notch
of ulna
Head of
radius
Neck of
radius
Interosseous
borders
– 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
Head of
radius
Coronoid process
Neck of
radius
Ulnar tuberosity
Radial
tuberosity
Ulna
Radius
Ulnar notch
of radius
Head of ulna
Styloid process
Styloid
process
Styloid
process
Articular facets
(a) Anterior view
• ulna
(b) Posterior view
Figure 8.33
– ligament attaches radius to
ulna along interosseous
margin of each bone
– enables the two elbow joints
to share the load
8-49
Carpal Bones
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Distal phalanx II
Middle phalanx II
Key to carpal bones
Distal row
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
Trapezoid
Trapezium
Carpal
Capitate
bones
Scaphoid
Figure 8.34a
8-50
Metacarpals and Phalanges
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Distal phalanx II
Middle phalanx II
Key to carpal bones
Distal row
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
Trapezoid
Trapezium
Carpal
Capitate
bones
Scaphoid
Figure 8.34a
8-51
•
•
pelvic girdle – consists of a complete ring
composed of three bones
– two hip (coxal) bones
• also called ossa coxae or
innominate bones
– sacrum that is also part of the vertebral
column
pelvis – bowl-shaped structure composed of
the two coxal bones and sacrum as well as
their ligaments and muscles that line the pelvic
cavity and form its floor
– supports trunk on the lower limbs
and protects viscera, lower colon, urinary
bladder, and internal reproductive organs
Pelvic Girdle
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Iliac
crest
Iliac
fossa
Base of
sacrum
Ilium
Sacroiliac joint
Anterior
superior
iliac spine
Pelvic surface
of sacrum
Anterior inferior
iliac spine
Pelvic inlet
Spine
•
sacroiliac joint - joins hipbone to
the vertebral column
– auricular surface of ileum to auricular
surface of sacrum
Ischium
Coccyx
Acetabulum
Body
Interpubic
disc
Ramus
Pubis
Obturator
foramen
Superior ramus
Inferior ramus
Body
Pubic symphysis
(a) Anterosuperior view
•
•
anteriorly, interpubic disc – pad of
fibrocartilage joins pubic bones
pubic symphysis – the interpubic disc and
adjacent regions of the pubic bone on each
side
Figure 8.35a
8-52
Pelvic Inlet and Outlet
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Iliac
crest
Iliac
fossa
Ilium
Anterior
superior
iliac spine
Anterior inferior
iliac spine
Spine
Ischium
Sacroiliac joint
Pelvic surface
of sacrum
Pelvic brim
Pelvic inlet
Coccyx
Pelvic inlet
Acetabulum
Body
Ramus
Pubis
Greater pelvis
Base of
sacrum
Superior ramus
Inferior ramus
Body
Lesser
pelvis
Interpubic
disc
Obturator
foramen
Pubic symphysis
(a) Anterosuperior view
Figure 8.35a
•
•
•
•
Pelvic outlet
(b) Median section
Figure 8.35b
greater (false) pelvis – between flare of the hips
lesser (true) pelvis – narrower and below
pelvic brim – round margin that separates the two
pelvic inlet – opening circumscribed by brim that infant’s
head must pass during birth
• pelvic outlet – lower margin of the lesser pelvis
8-53
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
– ischium
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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
– pubis (pubic bone)
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
8-54
Comparison of Male and Female
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Male
Female
Pelvic brim
Pelvic inlet
Obturator foramen
Pubic arch
90
Figure 8.37
120
• 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
8-55
Lower Limb
•
•
•
•
Femur (upper leg)
Patella (knee cap)
medial tibia and lateral fibula (lower leg)
7 tarsal bones, 5 metatarsals, and 14 phalanges in the toes (foot)
8-56
Femur
•
head that articulates with the acetabulum
of the pelvis
–
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forms ball-and-socket joint
Fovea capitis
Greater trochanter
Greater trochanter
Head
•
greater and lesser trochanters for muscle
attachment
•
medial and lateral condyles and
epicondyles found distally
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
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
8-57
Tibia
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Intercondylar eminence
Medial
condyle
Lateral condyle
Apex
Head of fibula
Tibial
tuberosity
Proximal tibiofibular
joint
• tibia - thick, medial, weightbearing bone
– medial and lateral condyles
• fairly flat articular surfaces
• articulate with condyle of
femur
Interosseous
membrane
Lateral surface
– tibial tuberosity – attachment
of quadricep muscles
Anterior crest
Tibia
– medial malleolus – bony knob
on inside of ankle
Fibula
Distal tibiofibular joint
Medial
malleolus
Lateral malleolus
(a) Anterior view
Figure 8.39
Lateral malleolus
(b) Posterior view
8-58
Fibula
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Intercondylar eminence
Medial
condyle
Lateral condyle
Apex
Head of fibula
Tibial
tuberosity
Proximal tibiofibular
joint
• does not bear any body
weight
Interosseous
membrane
Lateral surface
• fibula – slender, lateral
strut that helps stabilizes
ankle
Anterior crest
• lateral malleolus - distal
expansion, bony knob on
lateral side of ankle
Tibia
Fibula
• joined to tibia by
interosseous membrane
Distal tibiofibular joint
Medial
malleolus
Lateral malleolus
(a) Anterior view
Figure 8.39
Lateral malleolus
(b) Posterior view
8-59
The Ankle and Foot
• tarsal bones – arranged in
proximal and distal groups
• calcaneus – largest tarsal bone
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
– forms heel
– distal portion is point of attachment
for calcaneal (Achilles) tendon
Distal phalanx I
Distal
phalanx V
Proximal phalanx I
Middle
phalanx V
Metatarsal
I
II
• talus is most superior tarsal bone
Proximal
phalanx V
III
– forms ankle joint with tibia and
fibula
– sits upon calcaneus and articulates
with navicular
IV
V
Medial cuneiform
Intermediate cuneiform
Lateral cuneiform
Navicular
Cuboid
Talus
Calcaneus
Trochlear surface
of talus
Key to tarsal bones
Distal
group
Tuberosity of calcaneus
Proximal group
(a) Superior (dorsal) view
Figure 8.40a
8-60
The Foot
• remaining bones of foot are
similar in name and
arrangement to the hand
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• metatarsals
Distal phalanx I
Distal
phalanx V
Proximal phalanx I
Middle
phalanx V
Metatarsal
I
II
• phalanges
Proximal
phalanx V
III
IV
V
Medial cuneiform
Intermediate cuneiform
Lateral cuneiform
Navicular
Cuboid
Talus
Calcaneus
Trochlear surface
of talus
Key to tarsal bones
Distal
group
Tuberosity of calcaneus
Proximal group
(a) Superior (dorsal) view
Figure 8.40a
8-61