© 2013 Pearson Education, Inc. Skeletal System Composed of bones, cartilages, joints, ligaments 20%...
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Transcript of © 2013 Pearson Education, Inc. Skeletal System Composed of bones, cartilages, joints, ligaments 20%...
© 2013 Pearson Education, Inc.
Skeletal System
• Composed of bones, cartilages, joints, ligaments
• 20% of body mass
• Two major parts– Axial– Appendicular
© 2013 Pearson Education, Inc.
The Axial Skeleton
• Consists of 80 bones
• Three major regions– Skull– Vertebral column– Thoracic cage
© 2013 Pearson Education, Inc.
Figure 7.1a The human skeleton.
Anterior view
Radius
Rib
Skull
Thoracic cage(ribs andsternum)
Vertebralcolumn
Sacrum
TarsalsMetatarsalsPhalanges
Ulna
Vertebra
Humerus
Sternum
Scapula
Clavicle
Facial bones
Cranium
Fibula
Tibia
PatellaFemurMetacarpalsPhalanges
Carpals
© 2013 Pearson Education, Inc.
Metacarpals
Radius
Rib
Posterior view
Fibula
Tibia
Femur
Phalanges
Carpals
Ulna
Vertebra
Humerus
Sternum
Scapula
Clavicle
Cranium
Bones ofpectoralgirdle
Upperlimb
Bones ofpelvicgirdle
Lowerlimb
Figure 7.1b The human skeleton.
© 2013 Pearson Education, Inc.
The Skull
• Formed by two sets of bones1. Cranial bones (cranium)
• Enclose the brain in the cranial cavity• Provide sites of attachment for head and neck
muscles
© 2013 Pearson Education, Inc.
The Skull
2. Facial bones– Framework of face– Cavities for special sense organs for sight,
taste, and smell– Openings for air and food passage– Sites of attachment for teeth and muscles of
facial expression
© 2013 Pearson Education, Inc.
Figure 7.2a The skull: Cranial and facial divisions and fossae.
Bones of cranium
Coronal suture
Squamous suture
Lambdoidsuture
Facialbones
Cranial and facial divisions of the skull
© 2013 Pearson Education, Inc.
Figure 7.2b The skull: Cranial and facial divisions and fossae.
Anterior cranialfossa
Middle cranialfossa
Posterior cranialfossa
Superior view of the cranial fossae
© 2013 Pearson Education, Inc.
Skull Geography
• Cranial cavity
• Middle and internal ear cavities
• Nasal cavity
• Orbits
• 85 named openings– Foramina, canals, fissures
© 2013 Pearson Education, Inc.
Frontalbone
Zygomaticbone
Ethmoidbone
Inferiornasalconcha
Maxilla
Vomer
Mandible
Cranial cavity
Orbit Orbit
Oral cavity
Frontalsinus
Ethmoidalair cells
Maxillarysinus
Nasalcavity
Figure 7.3 Major cavities of the skull, frontal section.
© 2013 Pearson Education, Inc.
Eight Cranial Bones
• Frontal bone
• Parietal bones (2)
• Occipital bone
• Temporal bones (2)
• Sphenoid bone
• Ethmoid bone
© 2013 Pearson Education, Inc.
Frontal Bone
• Anterior portion of cranium
• Superior wall of orbits
• Contains air-filled frontal sinus
© 2013 Pearson Education, Inc.
Parietal bone
Squamous part of frontal boneNasal boneSphenoid bone(greater wing)
Temporal boneEthmoid boneLacrimal bone
Zygomatic bone
Infraorbital foramen
Maxilla
Mandible
Mentalforamen
Frontal bone
GlabellaFrontonasal sutureSupraorbital foramen(notch)Supraorbital marginSuperior orbitalfissureOptic canalInferior orbitalfissure
Middle nasal conchaPerpendicular plate
Ethmoidbone
Inferior nasal concha
Vomer
Suturalbone
Sagittal suture
Parietal bone Mandibularsymphysis
Lambdoidsuture
Occipital bone
Superior nuchal line
Externaloccipital protuberance
Occipitomastoidsuture External
occipitalcrest
Occipitalcondyle
Mastoidprocess oftemporal bone
Inferiornuchal line
Anterior view
Posterior view
Figure 7.4 Anatomy of the anterior and posterior aspects of the skull.
© 2013 Pearson Education, Inc.
Parietal Bones and Major Associated Sutures
• Superior and lateral aspects of cranial vault• Four sutures mark articulations of parietal bones
with frontal, occipital, and temporal bones:1. Coronal suture—between parietal bones and frontal
bone
2. Sagittal suture—between right and left parietal bones
3. Lambdoid suture—between parietal bones and occipital bone
4. Squamous (squamosal) sutures—between parietal and temporal bones on each side of skull
© 2013 Pearson Education, Inc.
Figure 7.5a Bones of the lateral aspect of the skull, external and internal views.
Coronal suture
Parietal bone
Temporal bone
Lambdoidsuture
Squamoussuture
Zygomaticprocess
Occipitalbone
OccipitomastoidsutureExternal acousticmeatusMastoid processStyloid process
Condylar processMandibular notch
Mandibular ramus
Frontal boneSphenoid bone(greater wing)
Ethmoid bone
Lacrimal bone
Lacrimal fossa
Nasal bone
Zygomatic boneMaxilla
Alveolarprocesses
MandibleMental foramen
Coronoid processMandibular angleExternal anatomy of theright side of the skull
© 2013 Pearson Education, Inc.
Figure 7.5b Bones of the lateral aspect of the skull, external and internal views.
Coronal suture
Parietal bone
SquamoussutureTemporal bone
ZygomaticprocessLambdoidsutureOccipitalbone
OccipitomastoidsutureExternal acousticmeatusMastoid process
Styloid process
CondylarprocessMandibular angle
Frontal boneSphenoid bone(greater wing)
Ethmoid bone
Lacrimal bone
Nasal bone
Lacrimal fossa
Zygomatic bone
Coronoid process
Maxilla
Alveolarprocesses
MandibleMental foramen
Mandibular notchMandibular ramus
Photograph of right side of skull
© 2013 Pearson Education, Inc.
Figure 7.5c Bones of the lateral aspect of the skull, external and internal views.
Nasal boneCrista galli
Sella turcicaof sphenoidbone
Internal acousticmeatus
External occipitalprotuberance
Occipitomastoidsuture
Occipitalbone
Lambdoidsuture
Temporalbone
Squamoussuture
Parietal bone
Coronal sutureFrontal bone
Sphenoid bone
Frontal sinus
Sphenoidal sinusEthmoid bone(perpendicular plate)
GreaterwingLesserwing
Palatine bone
Vomer
Maxilla
Palatine process of maxilla
Mandibularforamen
Pterygoidprocess ofsphenoid bone
Incisive fossa
Alveolar processes
Mandible
Midsagittal section showing the internal anatomy of the left half of skull
© 2013 Pearson Education, Inc.
Figure 7.5d Bones of the lateral aspect of the skull, external and internal views.
Petrous partof temporalbone
External occipitalprotuberance
Internal acousticmeatus
Sella turcica andsphenoidal sinus
Greater wing ofsphenoid bone
Lesser wing ofsphenoid bone
Frontal sinusCrista galli
Ethmoid bone(perpendicular plate)
Palatine bone
Photo of skull cut through the midline, same view as in (c)
© 2013 Pearson Education, Inc.
Occipital Bone
• Most of skull's posterior wall and posterior cranial fossa
• Articulates with 1st vertebra
• Sites of attachment for many neck and back muscles
© 2013 Pearson Education, Inc.
Figure 7.4b Anatomy of the anterior and posterior aspects of the skull.
Suturalbone
Sagittal suture
Parietal bone
Mastoidprocess oftemporal bone
Inferiornuchal line
Occipitalcondyle
Externaloccipitalcrest
Occipitomastoidsuture
Externaloccipital protuberance
Superior nuchal line
Occipital bone
Lambdoidsuture
Posterior view
© 2013 Pearson Education, Inc.
Figure 7.6a Inferior aspect of the skull, mandible removed.
Hardpalate
Maxilla(palatine process)
Palatine bone(horizontal plate)
Zygomatic bone
Temporal bone(zygomatic process)
Vomer
MandibularfossaStyloid process
Mastoid process
Temporal bone(petrous part)Basilar part of theoccipital boneParietal bone
External occipital crestExternal occipitalprotuberance
Inferior view of the skull (mandible removed)
Incisive fossaIntermaxillary sutureMedian palatine sutureInfraorbital foramenMaxilla
Sphenoid bone(greater wing)
Foramen ovale
Foramen spinosumForamen lacerumCarotid canalExternal acoustic meatusStylomastoidforamenJugular foramen
Occipital condyle
Inferior nuchal line
Superior nuchal lineOccipital bone
Foramen magnum
© 2013 Pearson Education, Inc.
Figure 7.6b Inferior aspect of the skull, mandible removed.
Zygomaticarch
Foramen ovale
Foramen lacerum
Foramen spinosum
Carotid canal
Styloid process
Jugular foramen
Occipital condyle
Foramen magnum
Superior nuchalline
Hard palate
Mandibularfossa
Mastoidprocess
Photo of inferior view of the skull
© 2013 Pearson Education, Inc.
Temporal Bones
• Inferolateral aspects of skull and parts of cranial floor
• Four major regions– Squamous– Tympanic– Mastoid– Petrous
© 2013 Pearson Education, Inc.
Figure 7.8 The temporal bone.
External acousticmeatus
Squamouspart
Petrouspart Mastoid process
Styloid process
Zygomaticprocess
Mandibularfossa
Tympanicpart
© 2013 Pearson Education, Inc.
Figure 7.6a Inferior aspect of the skull, mandible removed.
Hardpalate
Maxilla(palatine process)
Palatine bone(horizontal plate)
Zygomatic bone
Temporal bone(zygomatic process)
Vomer
MandibularfossaStyloid process
Mastoid process
Temporal bone(petrous part)Basilar part of theoccipital boneParietal bone
External occipital crestExternal occipitalprotuberance
Inferior view of the skull (mandible removed)
Incisive fossaIntermaxillary sutureMedian palatine sutureInfraorbital foramenMaxilla
Sphenoid bone(greater wing)
Foramen ovale
Foramen spinosumForamen lacerumCarotid canalExternal acoustic meatusStylomastoidforamenJugular foramen
Occipital condyle
Inferior nuchal line
Superior nuchal lineOccipital bone
Foramen magnum
© 2013 Pearson Education, Inc.
Figure 7.7a The base of the cranial cavity.
Foramen ovale
Cribriform plateCrista galli
Lesser wingGreater wing
ViewEthmoidbone
Anterior cranial fossa
Sphenoid
Hypophyseal fossaof sella turcicaMiddle cranialfossaTemporal bone(petrous part)
Posteriorcranial fossa
Parietal bone
Occipital bone
Foramen magnum
Superior view of the skull, calvaria removed
Frontal bone
Cribriform foramina
Optic canal
Foramen rotundum
Foramen spinosum
Foramen lacerum
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
© 2013 Pearson Education, Inc.
Figure 7.7b The base of the cranial cavity.
Crista galli Cribriform plateEthmoid
boneAnterior cranial fossa
Sphenoid Lesser wingGreater wing
Hypophyseal fossaof sella turcica
Middle cranialfossa
Temporal bone(petrous part)
Posteriorcranial fossa
Parietal bone
Occipital bone
Foramen magnum
Frontal bone
Cribriform foramina
Optic canal
Foramen rotundumForamen ovaleForamen spinosumForamen lacerum
Jugular foramen
Superior view of the skull, calvaria removed
© 2013 Pearson Education, Inc.
Sphenoid Bone
• Complex, bat-shaped bone
• Keystone bone– Articulates with all other cranial bones
• Three pairs of processes– Greater wings– Lesser wings– Pterygoid processes
© 2013 Pearson Education, Inc.
Figure 7.9a The sphenoid bone.
Opticcanal
Lesser wing
Superiororbitalfissure
ForamenrotundumForamenovaleForamenspinosumBody of sphenoid
Greaterwing
Hypophyseal fossa ofsella turcica
Superior view
© 2013 Pearson Education, Inc.
Figure 7.9b The sphenoid bone.
Lesser wing
Superior orbitalfissure
Pterygoidprocess
Body of sphenoid
Greaterwing
Posterior view
© 2013 Pearson Education, Inc.
Ethmoid Bone
• Deepest skull bone
• Superior part of nasal septum, roof of nasal cavities
• Contributes to medial wall of orbits
• Crista galli for dural attachment
© 2013 Pearson Education, Inc.
Figure 7.10 The ethmoid bone.
Crista galli
Cribriform platewith cribriformforamina
Leftlateralmass
Orbitalplate
Ethmoidal air cells
Perpendicularplate
Middlenasal concha
© 2013 Pearson Education, Inc.
Figure 7.4a Anatomy of the anterior and posterior aspects of the skull.
Parietal bone
Squamous part of frontal boneNasal boneSphenoid bone(greater wing)
Temporal boneEthmoid boneLacrimal bone
Zygomatic boneInfraorbital foramen
Maxilla
Mandible
Mentalforamen
Frontal bone
GlabellaFrontonasal sutureSupraorbital foramen(notch)Supraorbital marginSuperior orbitalfissureOptic canal
Inferior orbitalfissure
Middle nasal conchaPerpendicular plate
Inferior nasal concha
Vomer
Ethmoidbone
MandibularsymphysisAnterior view
© 2013 Pearson Education, Inc.
Figure 7.7a The base of the cranial cavity.
Foramen ovale
Cribriform plateCrista galli
Lesser wingGreater wing
ViewEthmoidbone
Anterior cranial fossa
Sphenoid
Hypophyseal fossaof sella turcicaMiddle cranialfossaTemporal bone(petrous part)
Posteriorcranial fossa
Parietal bone
Occipital bone
Foramen magnum
Superior view of the skull, calvaria removed
Frontal bone
Cribriform foramina
Optic canal
Foramen rotundum
Foramen spinosum
Foramen lacerum
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
© 2013 Pearson Education, Inc.
Sutural Bones
• Tiny irregularly shaped bones that appear within sutures
© 2013 Pearson Education, Inc.
Figure 7.4b Anatomy of the anterior and posterior aspects of the skull.
Suturalbone
Sagittal suture
Parietal bone
Mastoidprocess oftemporal bone
Inferiornuchal line
Occipitalcondyle
Externaloccipitalcrest
Occipitomastoidsuture
Externaloccipital protuberance
Superior nuchal line
Occipital bone
Lambdoidsuture
Posterior view
© 2013 Pearson Education, Inc.
• Lacrimal bones (2)• Palatine bones (2)• Vomer• Inferior nasal
conchae (2)
Fourteen Facial Bones
• Mandible• Maxillary bones
(maxillae) (2)• Zygomatic bones (2)• Nasal bones (2)
© 2013 Pearson Education, Inc.
Mandible
• Lower jaw
• Largest, strongest bone of face
• Temporomandibular joint– Only freely movable joint in skull
© 2013 Pearson Education, Inc.
Figure 7.11a Detailed anatomy of the mandible and the maxilla.
Temporomandibularjoint
Mandibular fossaof temporal bone
Coronoidprocess
Condylarprocess
Mandibular notch
Mandibular foramen
AlveolarprocessMentalforamen
Ramusof mandible
Mandibularangle Body of mandible
Mandible, right lateral view
© 2013 Pearson Education, Inc.
Maxillary Bones
• Medially fused to form upper jaw and central portion of facial skeleton
• Keystone bones– Articulate with all other facial bones except
mandible
• Contain maxillary sinuses– Largest of paranasal sinuses
© 2013 Pearson Education, Inc.
Figure 7.11b Detailed anatomy of the mandible and the maxilla.
ArticulateswithfrontalboneFrontalprocess
InfraorbitalforamenAnteriornasal spineAlveolarprocess
Orbital surface
Zygomaticprocess(cut)
Maxilla, right lateral view
© 2013 Pearson Education, Inc.
Figure 7.4a Anatomy of the anterior and posterior aspects of the skull.
Parietal bone
Squamous part of frontal boneNasal boneSphenoid bone(greater wing)
Temporal boneEthmoid boneLacrimal bone
Zygomatic boneInfraorbital foramen
Maxilla
Mandible
Mentalforamen
Frontal bone
GlabellaFrontonasal sutureSupraorbital foramen(notch)Supraorbital marginSuperior orbitalfissureOptic canal
Inferior orbitalfissure
Middle nasal conchaPerpendicular plate
Inferior nasal concha
Vomer
Ethmoidbone
Anterior view
Mandibularsymphysis
© 2013 Pearson Education, Inc.
Figure 7.6a Inferior aspect of the skull, mandible removed.
Hardpalate
Maxilla(palatine process)
Palatine bone(horizontal plate)
Zygomatic bone
Temporal bone(zygomatic process)
Vomer
MandibularfossaStyloid process
Mastoid process
Temporal bone(petrous part)Basilar part of theoccipital boneParietal bone
External occipital crestExternal occipitalprotuberance
Inferior view of the skull (mandible removed)
Incisive fossaIntermaxillary sutureMedian palatine sutureInfraorbital foramenMaxilla
Sphenoid bone(greater wing)
Foramen ovale
Foramen spinosumForamen lacerumCarotid canalExternal acoustic meatusStylomastoidforamenJugular foramen
Occipital condyle
Inferior nuchal line
Superior nuchal lineOccipital bone
Foramen magnum
© 2013 Pearson Education, Inc.
Zygomatic Bones
• Cheekbones
• Inferolateral margins of orbits
© 2013 Pearson Education, Inc.
Figure 7.4a Anatomy of the anterior and posterior aspects of the skull.
Parietal bone
Squamous part of frontal boneNasal boneSphenoid bone(greater wing)
Temporal boneEthmoid boneLacrimal bone
Zygomatic boneInfraorbital foramen
Maxilla
Mandible
Mentalforamen
Frontal bone
GlabellaFrontonasal sutureSupraorbital foramen(notch)Supraorbital marginSuperior orbitalfissureOptic canal
Inferior orbitalfissure
Middle nasal conchaPerpendicular plate
Inferior nasal concha
Vomer
Ethmoidbone
Anterior view
Mandibularsymphysis
© 2013 Pearson Education, Inc.
Nasal Bones and Lacrimal Bones
• Nasal bones– Form bridge of nose
• Lacrimal bones– In medial walls of orbits– Lacrimal fossa houses lacrimal sac
© 2013 Pearson Education, Inc.
Figure 7.5a Bones of the lateral aspect of the skull, external and internal views.
Coronal suture
Parietal bone
Temporal bone
Lambdoidsuture
Squamoussuture
Zygomaticprocess
Occipitalbone
OccipitomastoidsutureExternal acousticmeatusMastoid processStyloid process
Condylar processMandibular notch
Mandibular ramus
Frontal boneSphenoid bone(greater wing)
Ethmoid bone
Lacrimal bone
Lacrimal fossa
Nasal bone
Zygomatic boneMaxilla
Alveolarprocesses
MandibleMental foramen
Coronoid processMandibular angleExternal anatomy of theright side of the skull
© 2013 Pearson Education, Inc.
• Vomer– Plow shaped – Inferior part of
nasal septum
Palatine Bones and Vomer
• Palatine bones– Posterior one-third
of hard palate– Posterolateral walls
of the nasal cavity– Small part of the
orbits
© 2013 Pearson Education, Inc.
Figure 7.6a Inferior aspect of the skull, mandible removed.
Hardpalate
Maxilla(palatine process)
Palatine bone(horizontal plate)
Zygomatic bone
Temporal bone(zygomatic process)
Vomer
MandibularfossaStyloid process
Mastoid process
Temporal bone(petrous part)Basilar part of theoccipital boneParietal bone
External occipital crestExternal occipitalprotuberance
Inferior view of the skull (mandible removed)
Incisive fossaIntermaxillary sutureMedian palatine sutureInfraorbital foramenMaxilla
Sphenoid bone(greater wing)
Foramen ovale
Foramen spinosumForamen lacerumCarotid canalExternal acoustic meatusStylomastoidforamenJugular foramen
Occipital condyle
Inferior nuchal line
Superior nuchal lineOccipital bone
Foramen magnum
© 2013 Pearson Education, Inc.
Figure 7.13b Bones of the nasal cavity.
Ethmoidbone
Crista galliCribriformplate
Sella turcica
Sphenoidalsinus
Hardpalate
Palatine bone
Palatine processof maxilla
Frontal sinus
Nasal bone
Perpendicular plateof ethmoid bone
Septal cartilage
Vomer
Alveolar processof maxilla
Nasal cavity with septum in place showing the contributions of theethmoid bone, the vomer, and septal cartilage
© 2013 Pearson Education, Inc.
Inferior Nasal Conchae
• Form part of lateral walls of nasal cavity
• Largest of three pairs of conchae
© 2013 Pearson Education, Inc.
Frontal sinus
Superior, middle, andinferior meatus
Sphenoidbone
SphenoidalsinusPterygoidprocess
Palatine bone(perpendicularplate)
Palatine bone (horizontal plate)
Superiornasal conchaMiddlenasal concha
Inferior nasal conchaNasal bone
Anterior nasal spine
Ethmoidbone
Bones forming the left lateral wall of the nasal cavity(nasal septum removed)
Maxillary bone(palatine process)
Figure 7.13a Bones of the nasal cavity.
© 2013 Pearson Education, Inc.
Orbits
• Cavities that encase eyes and lacrimal glands
• Sites of attachment for eye muscles
• Formed by parts of seven bones– Frontal, sphenoid, zygomatic, maxilla,
palatine, lacrimal, and ethmoid
© 2013 Pearson Education, Inc.
Figure 7.12a Bones that form the orbits.
Photograph, right orbit
© 2013 Pearson Education, Inc.
Figure 7.12b Bones that form the orbits.
Roof of orbit Supraorbital notch
Superiororbital fissure
Optic canal • Lesser wing of sphenoid bone• Orbital plate of frontal bone Medial wall
Lateral wall of orbit • Zygomatic process of frontal bone• Greater wing of sphenoid bone• Orbital surface of zygomatic bone
Inferior orbital fissure
Zygomatic bone
• Sphenoid body• Orbital plate of ethmoid bone• Frontal process of maxilla• Lacrimal bone
Nasal bone
Floor of orbit• Orbital process of palatine bone• Orbital surface of maxillary bone• Zygomatic bone
Contribution of each of the seven bones forming the right orbit
Infraorbital groove
Infraorbitalforamen
© 2013 Pearson Education, Inc.
Nasal Cavity
• Roof, lateral walls, and floor formed by parts of four bones– Ethmoid– Palatine bones– Maxillary bones– Inferior nasal conchae
• Nasal septum of bone and hyaline cartilage– Perpendicular plate of ethmoid – Vomer – Anterior septal cartilage
© 2013 Pearson Education, Inc.
Frontal sinus
Superior, middle, andinferior meatus
Sphenoidbone
SphenoidalsinusPterygoidprocess
Palatine bone(perpendicularplate)
Palatine bone (horizontal plate)
Superiornasal conchaMiddlenasal concha
Inferior nasal conchaNasal bone
Anterior nasal spine
Ethmoidbone
Bones forming the left lateral wall of the nasal cavity(nasal septum removed)
Maxillary bone(palatine process)
Figure 7.13a Bones of the nasal cavity.
© 2013 Pearson Education, Inc.
Figure 7.13b Bones of the nasal cavity.
Ethmoidbone
Crista galliCribriformplate
Sella turcica
Sphenoidalsinus
Hardpalate
Palatine bone
Palatine processof maxilla
Frontal sinus
Nasal bone
Perpendicular plateof ethmoid bone
Septal cartilage
Vomer
Alveolar processof maxilla
Nasal cavity with septum in place showing the contributions of theethmoid bone, the vomer, and septal cartilage
© 2013 Pearson Education, Inc.
Paranasal Sinuses
• Mucosa-lined, air-filled spaces
• Lighten skull
• Enhance resonance of voice
• Warm and humidify air
• Found in frontal, sphenoid, ethmoid, and maxillary bones
© 2013 Pearson Education, Inc.
Figure 7.14a Paranasal sinuses.
Frontal sinus
Ethmoidal air cells(sinus)
Sphenoidal sinus
Maxillary sinus
Anterior aspect
© 2013 Pearson Education, Inc.
Frontal sinus
Ethmoidal air cells
Sphenoidal sinus
Maxillary sinus
Medial aspect
Figure 7.14b Paranasal sinuses.
© 2013 Pearson Education, Inc.
Hyoid Bone
• Not bone of skull
• Does not articulate directly with another bone
• Movable base for tongue
• Site of attachment for muscles of swallowing and speech
© 2013 Pearson Education, Inc.
Greater horn
Lesser horn
Body
Figure 7.15 The hyoid bone, anterior view.