Download Temporal Bone

THE SKELETAL SYSTEM
Focus on the Skull
Review Anatomical Terms
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Anterior/Posterior
Dorsal/Ventral
Medial/Lateral
Superior/Inferior
Bone Markings - Review
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Projections for attachment of muscles, ligaments and tendons
(Process, trochanter, tuberosity, tubercle, crest, line, spine)
Processes for articulation with other bones
(Head, neck, condyle, trochlea, facet)
Openings = holes or spaces in bone for nerves and vessels
to pass (Foramen, canal, meatus, fissure, sinus)
Depressions = indentations (Fossa, sulcus)
Axial Skeleton
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Includes bones of the skull, vertebral column and
thoracic cage
Creates a framework of support and protection for
internal organs
Provides sites of attachment of muscles
The Skull
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Protects the brain and supports delicate sense organs
Bones that form the skull include
8
cranial bones
 14 facial bones
 6 auditory ossicles (tiny bones in the ears)
 Hyoid bone (the only freely moveable bone)
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Bones are joined by sutures
Bones of the Cranium
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Frontal bone (1)- forms the forehead and roof of the
ocular orbits
Parietal Bone (2) – posterior to the frontal bone; forms the
sides and roof of skull
Occiptal Bone (1) – most posterior part of the cranium
 foramen
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magnum = large opening for spine
Temporal Bone (2) – form the sides and base of the skull;
a number of distinct anatomical landmarks
Sutures of the Cranium
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Sagittal Suture – midline suture; between parietal bones
Coronal Suture – between frontal bone and parietal
bones
Lambdoid Suture – between occipital and parietal bones
Squamous Suture– between the temporal bones and the
parietal bones
Bones and Sutures of the Cranium
Lateral View
Coronal Suture
Parietal Bone
Temporal Bone
Lambdoid Suture
Squamous Suture
Occipital Bone
Frontal Bone
Bones and Sutures of the Cranium
Frontal View
Coronal Suture
Parietal Bone
Frontal Bone
Temporal Bone
Bones and Sutures of the Cranium
Inferior View
Temporal Bone
Parietal Bone
Occipital Bone
Bones and Sutures of the Cranium
Horizontal View
Frontal Bone
Temporal Bone
Parietal Bone
Occipital Bone
REVIEW
The skull at birth
The skull at birth
Bones of the Cranium continued
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Sphenoid Bone– irregular bat-shaped bone forms part of
the cranial floor
Ethmoid Bone –stabilizes the brain; forms the roof and
sides of the nasal cavity
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Vomer – nasal septum
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Palatine Bone – posterior hard palate (“roof of mouth”)
Bones of the Cranium – Lateral View
Coronal Suture
Frontal Bone
Parietal Bone
Sphenoid Bone
Temporal Bone
Ethmoid Bone
Lambdoid
Suture
Squamous Suture
Occipital Bone
Bones of the Cranium - Frontal
Coronal Suture
Parietal Bone
Frontal Bone
Sphenoid Bone
Ethmoid Bone
Temporal Bone
Vomer
Bones of the Cranium – Inferior View
Palatine Bone
Sphenoid Bone
Vomer
Temporal Bone
Parietal Bone
Occipital Bone
Bones of the Cranium–Horizontal View
Frontal Bone
Sphenoid Bone
Temporal Bone
Parietal Bone
Occipital Bone
Ethmoid Bone
Facial Bones
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Maxilla (2) – anterior part of hard palate; upper jaw;
articulates with all other facial bones except the mandible
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Zygomatic Bones (2) – “cheek bones”
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Nasal Bones– bridge of nose
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Lacrimal Bones– tiny bones bearing tear ducts
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Mandible – lower jaw
Bones of the Face – Lateral View
Coronal Suture
Frontal Bone
Parietal Bone
Sphenoid Bone
Temporal Bone
Ethmoid Bone
Lambdoid
Suture
Squamous Suture
Occipital Bone
Lacrimal Bone
Nasal Bone
Zygomatic Bone
Maxilla
Mandible
Bones of the Face - Frontal
Coronal Suture
Parietal Bone
Frontal Bone
Nasal Bone
Sphenoid Bone
Ethmoid Bone
Lacrimal Bone
Zygomatic Bone
Temporal Bone
Maxilla
Mandible
Vomer
Bones of the Face – Inferior View
Maxilla
Palatine Bone
Zygomatic Bone
Vomer
Temporal Bone
Parietal Bone
Occipital Bone
Maxilla
Sphenoid Bone
Teeth (32)
Incisors
Canines
Pre-molars
Molars
Pre-molars
Canines
Incisors
Processes
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Any elevation or projection
Can be part of a joint or a site of attachment for
muscles, ligaments and tendons
Processes of the cranium
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PROCESS
Protrusion for
attachment of
tendons and
ligaments
Styloid process (temporal bone)
Mastoid process (temporal bone)
Zygomatic process (temporal bone)
Occipital condyle (occipital bone)
External occipital protuberance (occipital bone)
Coronoid process (mandible)
Condylar process (mandible)
Mandibular process (mandible)
Pterygoid process (sphenoid)
Hamulus of the pterygoid process (sphenoid)
Styloid Process
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Pointed piece of bone that extends down from the
temporal bone just below the ear
Attaches to
 ligaments
that support the hyoid bone
 muscles that control the tongue and pharynx
Mastoid Process
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Built up area of the lower temporal bone where important
neck muscles attach
Muscle that rotate and elevate the head and clavicle
attach here
Zygomatic Process of the Temporal Bone
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Connects temporal bone to facial bones (zygomatic
bone)
Occipital Condyle
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The site on the occipital bone where skull meets vertebrae
 Atlas
= the first vertebrae in the spinal column
External Occipital Protuberance
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Medial protrusion of the occipital bone
Muscles that keep the head upright and allow the head to
tilt backward attach here
Coronoid Process (coronation day)
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“like a crown”
Attachment point for muscle that closes the jaw
Condylar Process
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Forms a hinge with the temporal bone
Mandibular Process
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Smooth surface of the condylar process
The Sphenoid Bone
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Pterygoid Process and the hamulus of
the pterygoid process
Process of the Skull – Lateral View
Coronal Suture
Parietal Bone
Frontal Bone
Sphenoid Bone
Temporal Bone
Ethmoid Bone
Lambdoid Suture
Lacrimal Bone
Squamous Suture
Occipital Bone
Nasal Bone
Zygomatic Process
Zygomatic Bone
Maxilla
Mastoid Process
Styloid Process
Mandible
Process of the Skull - Frontal
Coronal Suture
Parietal Bone
Frontal Bone
Nasal Bone
Sphenoid Bone
Ethmoid Bone
Lacrimal Bone
Zygomatic Bone
Temporal Bone
Ethmoid Bone
Maxilla
Mandible
Vomer
Process of the Skull– Inferior View
Maxilla
Palatine Bone
Zygomatic Bone
Zygomatic Process
Maxilla
Sphenoid Bone
Vomer
Styloid Process
Mastoid Process
Temporal Bone
Parietal Bone
Occipital Bone
Occipital Condyle
Processes of the Skull – Horizontal View
Frontal Bone
Sphenoid Bone
Temporal Bone
Parietal Bone
Occipital Bone
Ethmoid Bone
Name the Process
Name the Process
Foramina and Other Structures
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General terms to describe openings include
 Foramen,
canal, meatus, fissure sinus
Foramina and Other Structures
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Supraorbital foramen (frontal)
Infraorbital foramen (maxilla)
Mental foramen (mandible)
Foramen magnum (occipital)
Jugular foramen (temporal)
Carotid canal (temporal)
External acoustic meatus (temporal)
Mandibular foramen (mandible)
Palatine foramen (palatine)
Foramen lacerum (temporal)
Foramen ovale (sphenoid)
Foramen spinosum (sphenoid)
Foramen rotundum (sphenoid)
Stylomastoid foramen (temporal)
FORAMEN,
MEATUS, FISSURE,
CANAL:
Terms to describe
openings for
passage of nerves
and blood vessels
Supraorbital foramen**
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“above” the orbit
blood vessels and nerves that innervate the
eyebrows and eyelids
Infraorbital foramen**
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“below the orbit”
Facial nerves
Mental foramen**
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Distal/lateral opening for the mental nerve and
vessels that innervate the lip
Mandibular foramen
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Proximal/medial opening for the mental nerve and
vessels that innervate the lip and teeth
Palatine foramen
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Nerves that innervate the palate
External Auditory meatus**
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Opening that leads to the eardrum (tympanum)
Foramen magnum**
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Spinal cord
Jugular foramen**
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Jugular vein
Carotid Canal**
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Carotid artery
Foramen ovale**
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Trigeminal nerve – mandibular branch
Foramen spinosum
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Nerves that innervate the meninges enter the brain
Foramen lacerum
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Fills with cartilage after birth
Foramen rotundum
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Trigeminal nerve: maxillary branch
Stylomastoid foramen
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Facial nerves exit skull
Foramina of the Skull – Lateral View
Coronal Suture
Frontal Bone
Parietal Bone
Sphenoid Bone
Temporal Bone
Ethmoid Bone
Lambdoid Suture
Lacrimal Bone
Squamous Suture
Occipital Bone
Nasal Bone
Zygomatic Bone
Maxilla
Zygomatic Process
External Auditory Meatus
Mastoid Process
Styloid Process
Mandible
Mandible
Mental Foramen
Foramina of the Skull - Frontal
Coronal Suture
Parietal Bone
Frontal Bone
Supraorbital Foramen
Nasal Bone
Sphenoid Bone
Ethmoid Bone
Lacrimal Bone
Zygomatic Bone
Superior Orbital Fissure
Optic Canal
Temporal Bone
Infraaorbital Foramen
Ethmoid Bone
Maxilla
Mandible
Vomer
Foramina of the Skull– Inferior View
Maxilla
Palatine Bone
Zygomatic Bone
Zygomatic Process
Vomer
Styloid Process
Mastoid Process
Temporal Bone
Parietal Bone
Occipital Bone
Maxilla
Sphenoid Bone
Foramen Ovale
Carotid Canal
Jugular Foramen
Occipital Condyle
Foramen Magnum
Foramina of the Skull – Horizontal View
Frontal Bone
Sphenoid Bone
Ethmoid Bone
Optic Canal
Foramen Ovale
Temporal Bone
Jugular Foramen
Carotid Canal
Parietal Bone
Occipital Bone
Foramen Magnum
Other Features
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Superior Nuchal Line
Inferior Nuchal Line
Mandibular foss
THE SKELETAL SYSTEM
Continue with the vertebrae
Vertebral Column
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Consists of 26 bones
 24
vertebrae
 Sacrum
 Coccyx
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Vertebrae separated by
cartilage (intervertebral
discs)
Subdivided based on
vertebral structure
Vertebrae Anatomy - general
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Vertebral body – massive weight bearing portion
Vertebral foramen – the opening through which the
spinal cord passes
Articular processes – extensions of the vertebrae that
articulate with other bones or provide attachment for
muscles
 Transverse
processes
 Superior articular processes
 Inferior articular processes
Vertebrae Anatomy - General
Vertebrae Anatomy by region
Cervical Region
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Seven cervical vertebrae (C1 to C7)
The first cervical vertebrae (C1; atlas) articulates
with the occipital condyle
Cervical region
Anatomical Features
 oval concave body
 large vertebral foramen
 Stumpy spinous process with a notched tip
 Transverse foramina within the transverse processes
 Protect
blood vessels supplying the brain
Cervical Vertebrae Anatomy
Cervical region
Spinous Process
Vertebral Arch
Lamina
Vertebral Foramen
Superior Articular Processes
Superior Articular Facet
Pedicle
Transverse Foramen
Transverse Process
Body
Cervical region
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The first two cervical vertebrae have unique
characteristics
C1 = ATLAS (‘yes)
 Articulation
of atlas with skull
allows you to nod your head
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C2 = AXIS (“no”)
 Articulation
of atlas and axis allows you to rotate your head
The Atlas and Axis
Dens (odontoid process)
Ligament
Articulates with
occipital condyles
Atlas
(C1)
Articulates with
atlas
Axis
(C2)
Thoracic Region
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Twelve cervical vertebrae (T1 to T12)
Each thoracic vertebrae articulates with one
or more pairs of ribs
Thoracic region
Vertebrae Anatomy
 Heart shaped body
 More massive than cervical vertebrae
 Large, slender spinous processes that point inferiorly
 Costal facets – for articulating with one or more pairs of
ribs
Vertebral Anatomy – thoracic region
Spinous Process
Transverse Process
Lamina
Articular facets
Vertebral Arch
Pedicle
Articular facets
Pedicle
Vertebral Foramen
Body
Lumbar Region
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Five lumbar vertebrae (L1 to L5)
The fifth lumbar vertebrae articulates
with the sacrum
Lumbar region
Vertebrae Anatomy
 Vertebral body is thick and more oval than thoracic
 Massive, stumpy spinous process that projects posteriorly
 Bladelike transverse processes; no articulation for ribs
 Most massive, least mobile
Vertebral Anatomy – lumbar region
Spinous Process
Vertebral Foramen
Lamina
Articular facets
Transverse Process
Pedicle
Body
Sacrum Region
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sacrum
Single bone formed by the fusion of 5 embryonic
vertebrae
Sacrum
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Protects reproductive, digestive and excretory organs
Attaches the axial skeleton to the appendicular skeleton
Broad surface – attachment of leg muscles
Bones fuse shortly after puberty
Prominent bulge (sacral promontory) is an important
landmark in females during labor and delivery
Coccyx
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Coccyx
Series of small fused vertebrae
Coccyx
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Attachment site for muscle that closes that anal opening
Fusion of the bone is not complete until late in adulthood
May eventually fuse with the sacrum
Normal Spinal Curvature
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Four spinal curves (seen in lateral view)
Primary curves
 Thoracic
and sacral curves
 Appear late in fetal development
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Secondary curves
 Cervical
curve as baby holds head up
 Lumbar curve as baby learns to stand
Normal Spinal Curvature
Spinal curvature development
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Cervical curvature develops as a baby learns to
hold its head
Spinal curvature development
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Lumbar curvature develops as a baby learns to
stand
Abnormal spinal curvature
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Several abnormal conditions can arise during
childhood and adolescence
Kyphosis – exaggerated thoracic curvature
Lordosis – exaggerated lumbar curvature
Scoliosis – abnormal lateral curvature
Kyphosis
Lordosis
Scoliosis
THE SKELETAL SYSTEM
Continue with the Thoracic Cage
Thoracic Cage
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Consists of the thoracic vertebrae, the ribs and the
sternum
 Ribs
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+ sternum = rib cage
Provides bony support for the walls of the thoracic cavity
Protects heart and lungs
Serves as base for muscles involved in respiration
Ribs
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AKA costal bones
Elongated flattened bones
12 pairs
 Ribs
1-7 = true ribs attach to the sternum by separate
cartilage extensions
 Ribs 8-10 = false ribs; do not attach directly to the sternum;
cartilages fuse before attachment
 Ribs 11-12 = floating ribs; do not connect to sternum at all
Sternum
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AKA breastbone
3 parts
Manubrium = Broad triangular part
articulates with clavicle
Elongated body articulates with ribs
Ziphoid process
1.
2.
3.
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Damage to this process can puncture the liver
CPR training places special emphasis on location of this part of the
sternum to reduce damage during compressions
Thoracic
vertebrae
Manubrium
True Ribs
Body
Sternum
Ziphoid
Process
Ribs
False Ribs
Costal Cartilage
Floating
Ribs