Download The Head and Neck

The Head and Neck
• Bones of the face
– See ADAM
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Cranial nerves – review
Trigeminal and facial nerves
Muscles of the face
Muscles of the neck
– Anterior and posterior triangles
– Cervical plexus
Bones of the skull and face
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Frontal
Parietal
Occipital
Temporal
Sphenoid
Maxilla
Mandible
Frontal bone
• Zygomatic
process
Parietal bone
• Sutures
– Bregma
– Lambda
Occipital bone
• Ext. Occipital
protuberance
• Nuchal lines
• Foramen magnum
• Occipital condyles
Temporal bone
• Zygomatic process
of temporal bone
– Zygomatic arch
• Styloid process
• Mastoid process
• Styloid-mastoid
foramen – CN VII
• External auditory
meatus
• Mandibular fossa
• Jugular foramen
Sphenoid bone
• Articulates with 8
bones
– Frontal, parietal,
temporal, occipital,
vomer, zygomatic,
palatine and
ethmoid
• Foramen ovale
– CN-V3
• Foramen lacerum
– ICA
• Foramen rotundum
– CN-V2
• Superior orbital
fissure
– CN-V1
– CN III, IV, VI
Zygomatic bone
• Prominence of cheeks
• Temporal process of zygomatic bone
– Zygomatic arch
Maxilla
Mandible
• Body
• Rami
– Condylar process
– Coronoid process
– Mandibular notch
• Angle of the mandible
• Mental foramen – inf. to 2nd premolar
• Mandibular foramen – inferior alveolar n.
Cranial nerves
• Know number, name, whether they are
sensory/motor/both, and basic function for
all
• CN I
• CN II
• CN III
• CN IV
• CN V – we will go into more detail
• CN VI
• CN VII – also in detail
• CN VIII
• CN IX
• CN X
• CN XI
• CN XII
Trigeminal Nerve
• Three divisions
– CN-V1 – Opthalmic Nerve
– CN-V2 – Maxillary Nerve
– CN-V3 – Mandibular Nerve
• How do they leave the skull?
– CN-V1 – Superior Orbital Fissure
– CN-V2 – Foramen rotundum
– CN-V3 – Foramen ovale
• The Trigeminal nerve is both sensory and
motor
• Sensory
– All three divisions
• Motor
– Muscles of mastication
– Just mandibular nerve
Major sensory nerves to the face
from the different divisions of CN-V
• Opthalmic nerve
– Supraorbital nerve
– External nasal nerve
– Infratrochlear nerve
– Supratrochlear nerve
– Lacrimal nerve
• Maxillary nerve
– Zygomaticotemporal nerve
– Zygomaticofacial nerve
– Infraorbital nerve
• Mandibular nerve
– Auriculotemporal nerve
– Buccal nerve
– Mental nerve
• Continuation of inferior alveolar nerve
– Lingual nerve
• Anterior 2/3rd of tongue, floor of the mouth, and
gums of the lower teeth
• Inferior alveolar nerve
– Branch of mandibular nerve
– Enters the mandible through the mandibular
foramen
– Supplies teeth in lower jaw
– Exits mandible through mental foramen to
form the mental nerve
Other sensory of CN-V
• Cornea of the eye
• Teeth
• Dura mater of the brain
Facial Nerve
• Primary nerve that supplies the muscles of
the face
– Muscles of facial expression
• Sensory to taste buds of the anterior 2/3rd
of tongue
• The facial nerve exits the skull through
the: Stylomastoid foramen
– The nerve enters the parotid gland and
branches into 5 divisions
Divisions of facial nerve
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Temporal branch of facial nerve
Zygomatic branch of facial nerve
Buccal branch of facial nerve
Mandibular branch of facial nerve
Cervical branch of facial nerve
• To Zanzibar By Motor Car
Muscles of facial expression
1. Origin is from either bone or fascia
2. Insertion is onto skin
3. Muscle actions
1. Primary function – sphincter or dilators
2. Secondary function – modify facial
expression
4. Innervated by branches of the facial
nerve
Zygomaticus minor muscle
(156)
• Nerve: B
• Muscle action: 1
Zygomaticus major muscle
(157)
• N: B
• A: 1,2
Levator anguli oris muscle (158)
• N: B
• A: 1
Buccinator muscle (163)
• N: Deep buccal branches of facial nerve
• A: 1
Risorius muscle (159)
• N: B
• A: 1
Orbicularis oris muscle (164)
• N: B and M
• A: 1, 2
Depressor anguli oris muscle
(160)
• N: M
• A: 1, 2
Depressor labia inferioris muscle
(161)
• N: M
• A: 1, 2
Mentalis muscle (162)
• N: M
• A: 1, 2
Platysma muscle (165)
• N: C
• A: 1, 2
Muscles of mastication
• Innervated by mandibular nerve (branch of
trigeminal nerve)
– Temporalis muscle
– Masseter muscle
– Pterygoid muscles (medial and lateral)
– Digastricus muscle (anterior belly)
Temporalis muscle (129)
• A:
Masseter muscle (130)
• A:
Medial pterygoid muscle (132)
• A:
Lateral pterygoid muscle (131)
• A:
Digastricus muscle (134)
• Anterior belly
– N: CN V
– A:
• Posterior belly
– N: CN VI
– A:
Muscles attached to the hyoid bone
• Suprahyoid muscles
– 4 muscles
– Location
– Digastricus is one
– Open jaw
• Infrahyoid muscles
– Location:
– Provide stabilization for hyoid bone and
suprahyoid muscles
Lateral Neck Muscles
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Sternocleidomastoid muscle
Scalenus anterior muscle
Scalenus medius muscle
Scalenus posterior muscle
Sternocleidomastoid muscle
(90)
• O:
– Sternal head - bold
– Clavicular head - all
• I: all
• N:
– APR of C2 and C3 – Pain, proprioception
– CN-XI
Sternocleidomastoid muscle
actions
• Chest stable
– Unilateral –
– Bilateral –
• Isometric contraction – helps stabilize
head on neck
• Head stable -
Scalenus anterior muscle (92)
• O: All
• I: All
• N:
Anterior scalene actions
• Chest stable
– Bilateral – Unilateral –
• Isometric actions – stabilizes head
• Stable head -
Scalenus medius muscle (93)
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Longest and largest scalene muscle
O:
I:
N:
A:
Scalenus posterior muscle (94)
• O:
• I:
• N:
• A:
• Brachial plexus travels between the scalenus
medius and scalenus anterior
Post skull
Lat skull
Anterior skull
Triangle neck - ant
Mandibular Nerve – CN-V
Lat skull