Download presentation
Presentation is loading. Please wait.
1
7 The Axial Skeleton
2
An Introduction to the Axial Skeleton
Learning Outcomes 7-1 Identify the bones of the axial skeleton, and specify their functions. 7-2 Identify the bones of the cranium and face, and explain the significance of the markings on the individual bones. 7-3 Identify the foramina and fissures of the skull, and cite the major structures using the passageways. 7-4 Describe the structure and functions of the orbital complex, nasal complex, and paranasal sinuses.
3
An Introduction to the Axial Skeleton
Learning Outcomes 7-5 Describe the key structural differences among the skulls of infants, children, and adults. 7-6 Identify and describe the curvatures of the spinal column, and indicate the function of each. 7-7 Identify the vertebral regions, and describe the distinctive structural and functional characteristics of vertebrae in each region. 7-8 Explain the significance of the articulations between the thoracic vertebrae and the ribs, and between the ribs and sternum.
4
An Introduction to the Axial Skeleton
Structures of Bones Articulations Contacts with other bones Landmarks (bone markings; marks) Areas of muscle and ligament attachment Foramina Openings for nerves and blood vessels
5
7-1 The Axial Skeleton The Axial Skeleton
Forms the longitudinal axis of the body Has 80 bones The skull 8 cranial bones 14 facial bones Bones associated with the skull 6 auditory ossicles The hyoid bone
6
7-1 The Axial Skeleton The Axial Skeleton The vertebral column
24 vertebrae (singular = vertebra) The sacrum The coccyx The thoracic cage 24 ribs The sternum
7
Figure 7-1a The Axial Skeleton
SKELETAL SYSTEM 206 APPENDICULAR SKELETON AXIAL SKELETON 80 (see Figure 8–1) 8 Cranium Skull 14 Face Skull and associated bones Auditory ossicles 29 6 Associated bones 1 Hyoid 1 Sternum Thoracic cage 25 24 Ribs 24 Vertebrae 1 Sacrum 26 Vertebral column 1 Coccyx An anterior view of the entire skeleton, with the axial components highlighted. The numbers in the boxes indicate the number of bones in the adult skeleton. 7
8
Figure 7-1b The Axial Skeleton
Skull Cervical vertebrae Sternum Thoracic vertebrae Ribs Costal cartilages Lumbar vertebrae Sacrum Coccyx Anterior (left) and posterior (right) views of the axial skeleton. The individual bones associated with the skull are not visible. 8
9
7-1 The Axial Skeleton Functions of the Axial Skeleton
Supports and protects organs in body cavities Attaches to muscles of head, neck, and trunk Performs respiratory movements Stabilizes parts of appendicular skeleton
10
7-2 The Skull The Skull Protects: The brain
Entrances to respiratory system Entrance to digestive system Contains: 22 bones 8 cranial bones Form the braincase or cranium 14 facial bones Protect and support entrances to digestive and respiratory tracts
11
Figure 7-2 Cranial and Facial Subdivisions of the Skull
FACE 14 CRANIUM 8 ASSOCIATED BONES 7 Maxillary bones 2 Occipital bone 1 Palatine bones 2 Parietal bones 2 Hyoid bone 1 Auditory ossicles enclosed in temporal bones (detailed in Chapter 17) Nasal bones 2 Frontal bone 1 6 Inferior nasal conchae 2 Temporal bones 2 Sphenoid 1 Zygomatic bones 2 Ethmoid 1 Lacrimal bones 2 Vomer 1 Mandible 1 11
12
Figure 7-2 Cranial and Facial Subdivisions of the Skull
FRONTAL BONE PARIETAL BONE SPHENOID TEMPORAL BONE ETHMOID OCCIPITAL BONE LACRIMAL BONE NASAL BONE Cranial bones VOMER ZYGOMATIC BONE MAXILLA MANDIBLE Facial bones 12
13
7-2 The Skull Cranial Bones Enclose the cranial cavity
Which contains the brain And its fluids, blood vessels, nerves, and membranes
14
7-2 The Skull Facial Bones Superficial facial bones
For muscle attachment Deep facial bones Separate the oral and nasal cavities Form the nasal septum
15
Figure 7-3a The Adult Skull
Sagittal suture PARIETAL BONE (left) PARIETAL BONE (right) Lambdoid suture OCCIPITAL BONE Squamous suture TEMPORAL BONE Mastoid process Styloid process Occipital condyle External occipital protuberance MANDIBLE Posterior view 15
16
Figure 7-3b The Adult Skull
OCCIPITAL BONE Lambdoid suture PARIETAL BONE (right) PARIETAL BONE (left) Sagittal suture Coronal suture FRONTAL BONE ZYGOMATIC BONE NASAL BONES Superior view 16
17
Figure 7-3c The Adult Skull
Coronal suture PARIETAL BONE FRONTAL BONE SPHENOID Squamous suture Supra-orbital foramen TEMPORAL BONE NASAL BONE LACRIMAL BONE Squamous part of temporal bone ETHMOID Lambdoid suture Infra-orbital foramen OCCIPITAL BONE MAXILLA External acoustic meatus ZYGOMATIC BONE Mastoid process Styloid process MANDIBLE Zygomatic process of temporal bone Mental foramen Zygomatic arch Temporal process of zygomatic bone Mental protuberance Lateral view 17
18
Figure 7-3d The Adult Skull
PARIETAL BONE Coronal suture FRONTAL BONE SPHENOID TEMPORAL BONE Supra-orbital foramen ETHMOID Optic canal PALATINE BONE Superior orbital fissure LACRIMAL BONE Inferior orbital fissure Temporal process of zygomatic bone ZYGOMATIC BONE Mastoid process of temporal bone Infra-orbital foramen NASAL BONE Middle nasal concha (part of ethmoid) MAXILLA Perpendicular plate of ethmoid INFERIOR NASAL CONCHA Bony nasal septum VOMER MANDIBLE Mental protuberance Mental foramen Anterior view 18
19
Figure 7-3e The Adult Skull
FRONTAL BONE ZYGOMATIC BONE MAXILLA VOMER SPHENOID PALATINE BONE Foreman ovale Zygomatic arch Medial and lateral pterygoid processes Styloid process Mandibular fossa Foramen lacerum Carotid canal External acoustic meatus TEMPORAL BONE Mastoid process Jugular foramen Stylomastoid foramen Lambdoid suture Occipital condyle OCCIPITAL BONE External occipital protuberance Foramen magnum Inferior view 19
20
Figure 7-4a The Sectional Anatomy of the Skull
Coronal suture PARIETAL BONE FRONTAL BONE SPHENOID Squamous suture Sphenoidal sinus (right) Frontal sinus TEMPORAL BONE Crista galli Lambdoid suture NASAL BONE ETHMOID Hypophyseal fossa of sella turcica VOMER Internal acoustic meatus PALATINE BONE OCCIPITAL BONE MAXILLA Hypoglossal canal Styloid process MANDIBLE Medial view of a sagittal section through the skull. 20
21
Figure 7-4b The Sectional Anatomy of the Skull
FRONTAL BONE Crista galli ETHMOID Cribriform plate Sella turcica Foramen rotundum SPHENOID Foramen lacerum Foramen ovale Foramen spinosum TEMPORAL BONE Carotid canal Internal acoustic meatus Foramen magnum PARIETAL BONE Jugular foramen Internal occipital crest Hypoglossal canal OCCIPITAL BONE Superior view of a horizontal section through the skull, showing the floor of the cranial cavity. Compare with part (a) and with Figure 7–3e. 21
22
7-2 The Skull Superficial Facial Bones Maxillae = maxillary bones
Lacrimal Nasal Zygomatic Mandible Deep Facial Bones Palatine Inferior nasal conchae Vomer
23
7-2 The Skull Sinuses Cavities that decrease the weight of the skull
Lined with mucous membranes Protect the entrances of the respiratory system
24
7-2 The Skull Sutures The immovable joints of the skull
The four major sutures Lambdoid suture Coronal suture Sagittal suture Squamous suture
25
7-2 The Skull Lambdoid Suture Coronal Suture
Separates occipital from parietal bones May contain sutural (Wormian) bones Coronal Suture Attaches frontal bone to parietal bones The calvaria (skullcap) Consists of occipital, parietal, and frontal bones
26
7-2 The Skull Sagittal Suture Squamous Sutures
Between the parietal bones From lambdoid suture to coronal suture Squamous Sutures Form boundaries between temporal bones and parietal bones
27
7-3 The Cranial Bones of the Skull
Occipital bone Parietal bones Frontal bone Temporal bones Sphenoid Ethmoid
28
7-3 The Cranial Bones of the Skull
The Occipital Bone Functions of the occipital bone Forms the posterior and inferior surfaces of the cranium Articulations of the occipital bone Parietal bones Temporal bones Sphenoid First cervical vertebra (atlas)
29
7-3 The Cranial Bones of the Skull
The Occipital Bone Marks of the occipital bone External occipital protuberance External occipital crest Occipital condyles articulate with neck Inferior and superior nuchal lines: attachment site of muscles and ligaments
30
7-3 The Cranial Bones of the Skull
The Occipital Bone Foramina of the occipital bone Foramen magnum connects cranial and spinal cavities Jugular foramen for jugular vein Hypoglossal canals for hypoglossal nerves
31
Figure 7-5a The Occipital and Parietal Bones
Hypoglossal canal Occipital condyle Foramen magnum External occipital crest Inferior nuchal line Superior nuchal line External occipital protuberance Occipital bone, inferior view 31
32
7-3 The Cranial Bones of the Skull
The Parietal Bones Functions of the parietal bones Form part of the superior and lateral surfaces of the cranium Articulations of the parietal bones Other parietal bone Occipital bone Temporal bone Frontal bone Sphenoid
33
7-3 The Cranial Bones of the Skull
The Parietal Bones Marks of the parietal bones Superior and inferior temporal lines To attach temporalis muscle Grooves for cranial blood vessels
34
Figure 7-5b The Occipital and Parietal Bones
Superior temporal line Inferior temporal line Right parietal bone, lateral view 34
35
7-3 The Cranial Bones of the Skull
The Frontal Bone Functions of the frontal bone Forms the anterior cranium and upper eye sockets Contains frontal sinuses Articulations of the frontal bone Parietal bone Maxillary Metopic suture Ethmoid Lacrimal bone Zygomatic bone Sphenoid Nasal bone
36
7-3 The Cranial Bones of the Skull
The Frontal Bone Marks of the frontal bone Frontal squama (forehead) Supra-orbital margin (protects eye) Lacrimal fossa (for tear ducts) Frontal sinuses
37
7-3 The Cranial Bones of the Skull
The Frontal Bone Foramina of the frontal bone Supra-orbital foramen For blood vessels of eyebrows, eyelids, and frontal sinuses Supra-orbital notch An incomplete supra-orbital foramen
38
Figure 7-6a The Frontal Bone
(metopic) suture Frontal squama Superior temporal line Supra-orbital margin Supra-orbital notch Anterior surface 38
39
Figure 7-6b The Frontal Bone
Supra-orbital foramen Frontal sinus Supra-orbital margin Lacrimal fossa Inferior (orbital) surface 39
40
7-3 The Cranial Bones of the Skull
The Temporal Bones Functions of the temporal bones Part of lateral walls of cranium and zygomatic arches Articulate with mandible Surround and protect inner ear Attach muscles of jaws and head
41
7-3 The Cranial Bones of the Skull
The Temporal Bones Articulations of the temporal bones Zygomatic bone Sphenoid Parietal bone Occipital bone Mandible
42
7-3 The Cranial Bones of the Skull
The Temporal Bones Marks of the temporal bones Squamous part Zygomatic process Mandibular fossa Mastoid process Styloid process Petrous part Auditory ossicles
43
7-3 The Cranial Bones of the Skull
Squamous Part Borders the squamous suture Zygomatic Process Inferior to the squamous portion Articulates with temporal process of zygomatic bone Forms zygomatic arch (cheekbone) Mandibular Fossa Articulates with the mandible
44
7-3 The Cranial Bones of the Skull
Mastoid Process For muscle attachment Contains mastoid air cells connected to middle ear Styloid Process To attach tendons and ligaments of the hyoid, tongue, and pharynx Petrous Part Encloses structures of the inner ear
45
7-3 The Cranial Bones of the Skull
Auditory Ossicles Three tiny bones in tympanic cavity (middle ear) Transfer sound from tympanic membrane (eardrum) to inner ear
46
7-3 The Cranial Bones of the Skull
The Temporal Bones Foramina of the temporal bones Carotid canal for internal carotid artery Foramen lacerum For carotid and small arteries Hyaline cartilage Auditory tube
47
7-3 The Cranial Bones of the Skull
The Temporal Bones Foramina of the temporal bones External acoustic meatus (canal) ends at tympanic membrane Stylomastoid foramen for facial nerve Internal acoustic meatus (canal) For blood vessels and nerves of the inner ear Facial nerve
48
Figure 7-7a The Temporal Bones
Petrous part Squamous part Internal acoustic meatus Mastoid process Zygomatic process Styloid process Medial view of the right temporal bone 48
49
Figure 7-7b The Temporal Bones
Squamous part Mandibular fossa External acoustic meatus Zygomatic process Styloid process Mastoid process Lateral view of the right temporal bone 49
50
Figure 7-7c The Temporal Bones
External acoustic meatus Mastoid process, cut to show mastoid air cells A cutaway view of the mastoid air cells 50
51
7-3 The Cranial Bones of the Skull
The Sphenoid Functions of the sphenoid Part of the floor of the cranium Unites cranial and facial bones Strengthens sides of the skull Contains sphenoidal sinuses
52
7-3 The Cranial Bones of the Skull
The Sphenoid Articulations of the sphenoid Ethmoid Frontal bone Occipital bone Parietal bone Temporal bone Palatine bones Zygomatic bones Maxillae Vomer
53
7-3 The Cranial Bones of the Skull
The Sphenoid Marks of the sphenoid Sphenoid body Sella turcica Hypophyseal fossa Sphenoidal sinuses Lesser wings Greater wings Pterygoid processes
54
7-3 The Cranial Bones of the Skull
Sphenoid Body At the central axis of the sphenoid Sella Turcica Saddle-shaped enclosure On the superior surface of the body Hypophyseal Fossa A depression within the sella turcica Holds the pituitary gland
55
7-3 The Cranial Bones of the Skull
Sphenoidal Sinuses On either side of the body Inferior to the sella turcica Lesser Wings Anterior to the sella turcica
56
7-3 The Cranial Bones of the Skull
Greater Wings Form part of the cranial floor Sphenoidal spine Posterior wall of the orbit Pterygoid Processes Form pterygoid plates To attach muscles of the lower jaw and soft palate
57
7-3 The Cranial Bones of the Skull
The Sphenoid Foramina of the sphenoid Optic canals for optic nerves Superior orbital fissure for blood vessels and nerves of the orbit Foramen rotundum for blood vessels and nerves of the face Foramen ovale for blood vessels and nerves of the face Foramen spinosum for blood vessels and nerves of the jaws
58
Superior surface Foramen rotundum Optic groove Optic canal Lesser wing
Figure 7-8a The Sphenoid Foramen rotundum Optic groove Optic canal Lesser wing Foramen ovale Greater wing Foramen spinosum Sphenoidal spine Sella turcica Superior surface 58
59
Anterior surface Superior orbital fissure Sphenoidal sinus Lesser wing
Figure 7-8b The Sphenoid Superior orbital fissure Sphenoidal sinus Lesser wing Greater wing Orbital surface Body Foramen rotundum Pterygoid process Pterygoid plates Anterior surface 59
60
7-3 The Cranial Bones of the Skull
The Ethmoid Functions of the ethmoid Forms anteromedial floor of the cranium Roof of the nasal cavity Part of the nasal septum and medial orbital wall Contains ethmoidal air cells (network of sinuses)
61
7-3 The Cranial Bones of the Skull
The Ethmoid Articulations of the ethmoid Frontal bone Sphenoid Nasal bone Lacrimal bone Palatine bone Maxillary bones Inferior nasal conchae Vomer
62
7-3 The Cranial Bones of the Skull
The Ethmoid Three parts of the ethmoid The cribriform plate The two lateral masses The perpendicular plate
63
7-3 The Cranial Bones of the Skull
The Cribriform Plate Floor of the cranium Roof of the nasal cavity Contains the crista galli The Two Lateral Masses Ethmoidal labyrinth (ethmoidal air cells) Superior nasal conchae Middle nasal conchae The Perpendicular Plate Part of the nasal septum
64
7-3 The Cranial Bones of the Skull
The Ethmoid Foramina of the ethmoid Olfactory foramina In the cribriform plate For olfactory nerves
65
Superior surface Lateral mass containing ethmoidal Olfactory labyrinth
Figure 7-9a The Ethmoid Lateral mass containing ethmoidal labyrinth Olfactory foramina Cribriform plate Crista galli Perpendicular plate Superior surface 65
66
Posterior surface Crista galli Superior nasal concha Perpendicular
Figure 7-9b The Ethmoid Crista galli Superior nasal concha Perpendicular plate Middle nasal concha Posterior surface 66
67
7-3 The Facial Bones of the Skull
Maxillae (maxillary bones) Palatine bones Nasal bones Vomer Inferior nasal conchae Zygomatic bones Lacrimal bones Mandible
68
7-3 The Facial Bones of the Skull
The Maxillae Functions of the maxillae Support upper teeth Form inferior orbital rim Form lateral margins of external nares Form upper jaw and hard palate Contain maxillary sinuses (largest sinuses)
69
7-3 The Facial Bones of the Skull
The Maxillae Articulations of the maxillae Frontal bones Ethmoid With one another All other facial bones except the mandible
70
7-3 The Facial Bones of the Skull
The Maxillae Marks of the maxillae Orbital rim protects eye and orbit Anterior nasal spine attaches cartilaginous anterior nasal septum Alveolar processes border the mouth and support upper teeth Palatine processes form the hard palate (roof of mouth) Maxillary sinuses lighten bone Nasolacrimal canal protects lacrimal sac and nasolacrimal duct
71
7-3 The Facial Bones of the Skull
The Maxillae Foramina of the maxillae Infra-orbital foramen For sensory nerve to brain (via foramen rotundum of sphenoid) Inferior orbital fissure For cranial nerves and blood vessels
72
Figure 7-10a The Maxillae and Palatine Bones
Orbital rim Infra-orbital foramen Anterior nasal spine Alveolar process Zygomatic process An anterolateral view of the right maxilla. 72
73
7-3 The Facial Bones of the Skull
The Palatine Bones Functions of the palatine bones Form the posterior portion of the hard palate Contribute to the floors of the orbits
74
7-3 The Facial Bones of the Skull
The Palatine Bones Articulations of the palatine bones With other palatine bone Maxillae Sphenoid Ethmoid Inferior nasal conchae Vomer
75
7-3 The Facial Bones of the Skull
The Palatine Bones Divisions of the palatine bones Horizontal plate: posterior part of hard palate Perpendicular plate from horizontal plate to orbital process of orbit floor Foramina of the palatine bones Many in the lateral portion of the horizontal plate For small blood vessels and nerves of the roof of the mouth
76
Figure 7-10b The Maxillae and Palatine Bones
(horizontal plate) Palatine process Alveolar process Maxillary sinus Superior view of a horizontal section through right maxilla and palatine bone; note the size and orientation of the maxillary sinus. 76
77
Figure 7-10c The Maxillae and Palatine Bones
Orbital process Perpendicular plate Horizontal plate An anterior view of the two palatine bones. 77
78
7-3 The Facial Bones of the Skull
The Nasal Bones Functions of the nasal bones Support the bridge of the nose Connect to cartilages of the distal part of the nose (external nares)
79
7-3 The Facial Bones of the Skull
The Nasal Bones Articulations of the nasal bones With other nasal bones Ethmoid Frontal bones Maxillae
80
7-3 The Facial Bones of the Skull
The Vomer Functions of the vomer Forms the inferior portion of the bony nasal septum Articulations of the vomer Sphenoid Ethmoid Palatine bones Maxillae Cartilaginous part of the nasal septum
81
7-3 The Facial Bones of the Skull
The Inferior Nasal Conchae Functions of the inferior nasal conchae To create air turbulence in the nasal cavity To increase the epithelial surface area To warm and humidify inhaled air
82
7-3 The Facial Bones of the Skull
The Inferior Nasal Conchae Articulations of the inferior nasal conchae Ethmoid Maxillae Palatine bones Lacrimal bones
83
7-3 The Facial Bones of the Skull
The Zygomatic Bones Functions of the zygomatic bones Contribute to the rim and lateral wall of the orbit Form part of the zygomatic arch Articulations of the zygomatic bones Sphenoid Frontal bone Temporal bones Maxillae
84
7-3 The Facial Bones of the Skull
The Zygomatic Bones Marks of the zygomatic bones Temporal process Meets the zygomatic process of the temporal bone Foramina of the zygomatic bones Zygomaticofacial foramen For sensory nerves of cheeks
85
7-3 The Facial Bones of the Skull
The Lacrimal Bones Functions of the lacrimal bones The smallest facial bones Form part of the medial wall of the orbit Articulations of the lacrimal bones Frontal bone Maxillae Ethmoid
86
7-3 The Facial Bones of the Skull
The Lacrimal Bones Marks of the lacrimal bones Lacrimal sulcus Location of the lacrimal sac Leads to the nasolacrimal canal (between orbit and nasal cavity)
87
Figure 7-11 The Smaller Bones of the Face
Supra-orbital foramen NASAL BONE SPHENOID TEMPORAL BONE Zygomaticofacial foramen ZYGOMATIC BONE Infra-orbital foramen MAXILLA Perpendicular plate of ethmoid VOMER Bony nasal septum 87
88
Figure 7-11 The Smaller Bones of the Face
Lacrimal sulcus Optic canal Superior orbital fissure LACRIMAL BONE Middle nasal concha INFERIOR NASAL CONCHA Temporal process of zygomatic bone Mastoid process Perpendicular plate of ethmoid VOMER Bony nasal septum 88
89
7-3 The Facial Bones of the Skull
The Mandible Functions of the mandible Forms the lower jaw Articulations of the mandible Mandibular fossae of the temporal bones
90
7-3 The Facial Bones of the Skull
The Mandible Marks of the mandible Body of the mandible horizontal portion Alveolar processes support the lower teeth Mental protuberance attaches facial muscles A depression on the medial surface for submandibular salivary gland Mylohyoid line for insertion of the mylohyoid muscle (floor of mouth)
91
7-3 The Facial Bones of the Skull
The Mandible Marks of the mandible Ramus ascending from the mandibular angle on either side Condylar process articulates with temporal bone at temporomandibular joint Coronoid process: insertion point for temporalis muscle (closes the jaws) Mandibular notch separates condylar and coronoid processes
92
7-3 The Facial Bones of the Skull
The Mandible Foramina of the mandible Mental foramina For sensory nerves of lips and chin Mandibular foramen Entrance to the mandibular canal For blood vessels and nerves of lower teeth
93
7-3 The Facial Bones of the Skull
The Hyoid Bone Functions of the hyoid bone Supports the larynx Attaches muscles of the larynx, pharynx, and tongue Articulations of the hyoid bone Connects lesser horns to styloid processes of temporal bones
94
7-3 The Facial Bones of the Skull
The Hyoid Bone Marks of the hyoid bone Body of the hyoid Attaches muscles of larynx, tongue, and pharynx
95
7-3 The Facial Bones of the Skull
The Hyoid Bone Marks of the hyoid bone Greater horns (greater cornua) Support larynx Attach muscles of the tongue Lesser horns (lesser cornua) Attach stylohyoid ligaments Support hyoid and larynx
96
Figure 7-12a The Mandible and Hyoid Bone
Articular surface for temporomandibular joint Coronoid process Teeth Mandibular notch Alveolar process Head Ramus Body Mental protuberance Condylar process Mental foramen Angle A lateral and slightly superior view of the mandible 96
97
Figure 7-12b The Mandible and Hyoid Bone
Articular surface Alveolar process Condylar process Coronoid process Mandibular foramen Mylohyoid line Depression for submandibular salivary gland A medial view of the right mandible 97
98
Figure 7-12c The Mandible and Hyoid Bone
Greater horn Lesser horn Body An anterior view of the hyoid bone 98
99
7-4 The Orbital and Nasal Complexes
The Eye Sockets (Orbits) Frontal bone (roof) Maxilla (floor) Maxillary, lacrimal, and ethmoid bones (orbital rim and medial wall) Sphenoid and palatine bones
100
Figure 7-13 The Orbital Complex
FRONTAL BONE Supra-orbital notch SPHENOID Optic canal ETHMOID Superior orbital fissure LACRIMAL BONE Lacrimal sulcus Inferior orbital fissure Nasolacrimal canal ZYGOMATIC BONE PALATINE BONE Infra-orbital groove Infra-orbital foramen MAXILLA 100
101
Figure 7-13 The Orbital Complex
Supra-orbital notch FRONTAL BONE SPHENOID Optic canal Superior orbital fissure ETHMOID Nasolacrimal canal Inferior orbital fissure Infra-orbital groove ZYGOMATIC BONE MAXILLA Infra-orbital foramen 101
102
7-4 The Orbital and Nasal Complexes
Bones of the Nasal Cavities and Paranasal Sinuses Make Up the Nasal Complex Frontal bone, sphenoid, and ethmoid Superior wall of nasal cavities Maxillae, lacrimal bones, ethmoid, and inferior nasal conchae Lateral walls of nasal cavities Maxillae and nasal bones Bridge of nose
103
Figure 7-14a The Nasal Complex
FRONTAL BONE Frontal sinuses Sphenoidal sinuses ETHMOID NASAL BONE SPHENOID PALATINE BONE (bony palate) Superior Nasal conchae of ethmoid MAXILLA (bony palate) Middle INFERIOR NASAL CONCHA A sagittal section through the skull, with the nasal septum removed to show major features of the wall of the right nasal cavity. The sphenoidal sinuses are visible. 103
104
Figure 7-14b The Nasal Complex
FRONTAL BONE Cranial cavity Frontal sinus Right orbit Ethmoidal air cell Superior nasal concha Perpendicular plate of ethmoid Middle nasal concha Maxillary sinus ZYGOMATIC BONE INFERIOR NASAL CONCHA VOMER MAXILLA (bony palate) Tongue MANDIBLE A frontal section through the ethmoidal air cells and maxillary sinuses, part of the paranasal sinuses. 104
105
7-4 The Orbital and Nasal Complexes
Paranasal Sinuses Air-filled chambers connected to the nasal cavities Lighten skull bones Provide mucous epithelium (flushes nasal cavities)
106
7-5 Fontanelles The Infant Skull Grows rapidly
Is large compared to the body Has many ossification centers
107
7-5 Fontanelles The Infant Skull Fusion is not complete at birth
Two frontal bones Four occipital bones Several sphenoidal and temporal elements
108
7-5 Fontanelles Fontanelles
Are areas of fibrous connective tissue (soft spots) Cover unfused sutures in the infant skull Allow the skull to flex during birth
109
7-5 Fontanelles Anterior Fontanelle Occipital Fontanelle
Frontal, sagittal, and coronal sutures Occipital Fontanelle Lambdoid and sagittal sutures Sphenoidal Fontanelles Squamous and coronal sutures Mastoid Fontanelles Squamous and lambdoid sutures
110
Figure 7-15a The Skull of an Infant
Coronal suture FRONTAL BONE PARIETAL BONE Sphenoidal fontanelle NASAL BONE Squamous suture Lambdoid suture MAXILLA OCCIPITAL BONE SPHENOID MANDIBLE TEMPORAL BONE Mastoid fontanelle Lateral view 110
111
Figure 7-15b The Skull of an Infant
PARIETAL BONE FRONTAL BONE Lambdoid suture Coronal suture Sagittal suture Frontal suture Anterior fontanelle OCCIPITAL BONE FRONTAL BONE PARIETAL BONE Occipital fontanelle Superior view 111
112
7-6 The Vertebral Column The Vertebral Column (Spine)
Protects the spinal cord Supports the head and body 26 bones 24 vertebrae, the sacrum, and the coccyx
113
Figure 7-16 The Vertebral Column
Spinal Curves Vertebral Regions Primary curves develop before birth, and secondary curves after birth. Regions are defined by anatomical characteristics of individual vertebrae. The cervical curve, a secondary curve, develops as the infant learns to balance the weight of the head on the vertebrae of the neck. Cervical (7 vertebrae) The thoracic curve, a primary curve, accommodates the thoracic organs. Thoracic (12 vertebrae) The lumbar curve, a secondary curve, balances the weight of the trunk over the lower limbs; it develops with the ability to stand. Lumbar (5 vertebrae) The sacral curve, a primary curve, accommodates the abdominopelvic organs. Sacral Coccygeal 113
114
7-6 The Vertebral Column Vertebrae The neck The upper back
Seven cervical vertebrae The upper back 12 thoracic vertebrae Each articulates with one or more pair of ribs The lower back Five lumbar vertebrae
115
7-6 The Vertebral Column The Sacrum and Coccyx
The fifth lumbar vertebra articulates with the sacrum The sacrum articulates with the coccyx
116
7-6 The Vertebral Column Four Spinal Curves Cervical curve
Thoracic curve Lumbar curve Sacral curve
117
7-6 The Vertebral Column Thoracic and Sacral Curves
Are called primary curves (present during fetal development) Or accommodation curves (accommodate internal organs) Lumbar and Cervical Curves Are called secondary curves (appear after birth) Or compensation curves (shift body weight for upright posture)
118
Figure 7-17a Abnormal Curvatures of the Spine
Kyphosis 118
119
Figure 7-17b Abnormal Curvatures of the Spine
Lordosis 119
120
Figure 7-17c Abnormal Curvatures of the Spine
Scoliosis 120
121
7-6 The Vertebral Column Vertebral Anatomy
The vertebral body (centrum) Transfers weight along the spine The vertebral arch Posterior margin of vertebral foramen The articular processes Lateral projections between laminae and pedicles
122
Figure 7-18a Vertebral Anatomy
Articular processes Vertebral arch Vertebral body The major components of a typical vertebra 122
123
7-6 The Vertebral Column Vertebral Anatomy The vertebral arch Pedicles
Walls of the vertebral arch Laminae Roof of the vertebral arch
124
7-6 The Vertebral Column Vertebral Anatomy The vertebral arch
Spinous process Projection where vertebral laminae fuse Transverse process Projection where laminae join pedicles
125
7-6 The Vertebral Column Vertebral Anatomy The articular processes
Superior articular process Inferior articular process Have articular facets on articular faces
126
Figure 7-18b Vertebral Anatomy
Superior articular process Pedicle Transverse process Vertebral body Spinous process Inferior articular facet Arrow passing through vertebral foramen Inferior articular process A lateral and slightly inferior view of a vertebra 126
127
Figure 7-18c Vertebral Anatomy
Spinous process Superior articular process Inferior articular process Transverse process Pedicle Inferior articular facet Vertebral foramen Vertebral body An inferior view of a vertebra 127
128
7-6 The Vertebral Column Vertebral Foramina Intervertebral foramina
Gaps between pedicles of adjacent vertebrae For nerve connections to spinal cord Vertebral canal Formed by vertebral foramina Encloses the spinal cord
129
7-6 The Vertebral Column Intervertebral Discs
Are pads of fibrocartilage Separate the vertebral bodies Absorb shocks
130
Figure 7-18d Vertebral Anatomy
Superior articular facets Superior articular process Lamina of vertebral arch Spinous process Intervertebral disc Transverse process Vertebral body Inferior articular process An posterior view of three articulated vertebrae 130
131
Figure 7-18e Vertebral Anatomy
Superior articular facets Lamina of vertebral arch Intervertebral foramen Intervertebral disc Spinous process Transverse process Vertebral body Inferior articular facet Arrow passing through vertebral canal A lateral and sectional view of three articulated vertebrae 131
Similar presentations
