Anatomy: Neck (Temporal Region, Infratemporal Fossa, Pharynx)

Front 1

Temporal Region (Boundaries)

Back 1

Superior: Flat bones of the skull; frontal, parietal, sphenoid (greater wing), temporal (squamous part).

Inferior: Zygomatic arch.
Bony floor is origin for temporalis m.

Front 2

Muscles of Mastication

Back 2

-Temporalis m.
-Masseter m.
-Lateral pterygoid m.
-Medial pterygoid m.

Front 3

Infratemporal Fossa

Back 3

- Located below the zygomatic arch deep to the mandible.
- Contains lateral and medial pterygoid mm., maxillary a., and numerous branches of trigeminal nerve (V3)

Front 4

Infratemporal Fossa (Boundaries)

Back 4

Superior: Zygomatic Arch

Lateral: Mandible

Medial: Lateral pterygoid plate of sphenoid bone.

Anterior: Posterior aspect of maxilla

Front 5

Infratemporal Fossa (Communications)

Back 5

- Temporal Fossa: beneath zygomatic arch.
- Orbit: via inferior orbital fissure.
-Middle cranial fossa: via foramen ovale and foramen spinosum.
-Mandibular canal: via mandibular foramen.

Front 6

Infratemporal Fossa (Nerves)

Back 6

-Most nerves are branches of the mandibular division (V3) of the trigeminal n.

- Exception is the chorda tympani n. from facial n. (CN VII).
- It fuses with lingual n. of V3 to add parasympathetic fibers to submandibular and sublingual salivary glands, and taste fibers to anterior 2/3 of tongue.

Front 7

Infratemporal Fossa (Arteries)

Back 7

Branches of the maxillary a. supply contents of temporal region and infratemporal fossa.

Front 8

Temporalis m.

Back 8

Action: elevation and retraction of mandible

Innervation: Deep temporal n. (V3)

Front 9

Masseter m.

Back 9

Action: elevation and protraction of mandible.

Innervation: Masseteric n. (V3)

Front 10

Medial pterygoid m.

Back 10

Action: elevation and protraction of mandible.

Innervation: V3

Front 11

Lateral pterygoid m.

Back 11

Action: Pulls articular disc forward, (protraction) of mandible when depressed.

Innervation: V3

Front 12

Depressors of Mandible

Back 12

- digastric m.
- infrahyoid mm.
- latreral pterygoid m.

Front 13

Jaw jerk reflex

Back 13

- used to test status of trigeminal n. (CN V).
- mandible is tapped at downward angle and mandible will jerk the mandible upwards.
- Normally absent or slight response, but if there is a lesion then response can be pronounced.

Front 14

V3 lesion

Back 14

- atrophy of masseter m.
- opened jaw deviates towards side of lesion.

Front 15

Nerves of Infratemporal Fossa

Back 15

Branches of Mandibular division (V3) of Trigeminal n. (CN V):
-Deep temporal n.
-Auriculotemporal n.
-Masseteric n.
-Inferior alveolar n.(supplies nn. to mandibular teeth via dental plexus)
- Lingual n.
-Buccal n.

Front 16

Contributions to lingual n.

Back 16

Lingual nerve contains parasympathetic fibers from V3 division and fibers from chorda tympani n. (CN VII).

Front 17

Organization of Sublingual and Submandibular gland innervation

Back 17

Parasympathetic Input:
- Comes from CN VII branch called chorda tympani, and are preganglionic fibers.
-Synapse of preganglionic fiber onto postganglion cell occurs in submandibular ganglion.
- supply innervates the two glands myoepithelial cells.

Sympathetic Input:
- Comes from postganglionic fibers.
-Fibers innervate smooth muscle of blood vessels within the salivary glands.

Front 18

Results of Epidural hematoma causing Uncal herniation

Back 18

Epidural hematoma can result in an uncal herniation, which can cause impingement of the posterior cerebral a. and CN III.

Effects can be--- ptosis of upper eyelid and mydriasis (dilated pupil) on affected ipsilateral side.

Front 19

Temporomandibular Joint: Articulating surfaces and Features

Back 19

Articulating Surfaces:
-Mandibular fossa
-Articular eminence of temporal bone
-Articular Disc
-Head of condyle of mandible

Features:
-Joint Capsule
-Synovial membrane
-Synovial Cavities

Front 20

Movements of TMJ

Back 20

-Hinge motion: between head of condyle and articulating disc
-Gliding Motion: between articulating disc and articular eminece
-both movements lead to depression and elevation of mandible.

- (Grinding Motions)Retraction and protraction: functions of contraction of lateral pterygoid m. on one side and contraction of temporalis m. on opposite side.

Front 21

Dislocation of TMJ

Back 21

-Mouth remains wide open and person may not be able to close it.
- Close relationship of facial n. and auriculotemporal nn. to TMJ must be considered for treatment.

-Damage to articular branches of auriculotemporal n. can result in laxity and instability of TMJ

Front 22

Craniovertebral Region

Back 22

Area of C1 and C2 cervical vertebrae that form special joint called median atlantoaxial joint.

Front 23

Median atlantoaxial joint (Bony components)

Back 23

C1 Vertebra (atlas):
-No spinous process or body
-Ring shaped w/ anterior and posterior arches connected to 2 lateral masses
-Inner aspect of anterior arch articulates with dens of axis

C2 vertebra (axis): Body has upward extension called the dens or odontoid process.

Front 24

Median atlantoaxial joint: Alar ligaments

Back 24

Alar ligaments:
- two in number
-form wing-like configuration
-extend upward from sides of dens to medial aspects of occipital condyles (dens to occipital bones attach axis to skull)
-prevent excessive rotation at joint
-rumored to be strongest ligaments in the body

Front 25

Median atlantoaxial joint: Cruciform ligaments

Back 25

-cross like
- transverse ligament of atlas extends horizontally posterior to dens and attaches on either side to lateral masses of atlas.

Front 26

Other Joints

Back 26

Atlanto-occipital joints (atlas to occipital bone):
-occipital condyles articulate with superior articular facets of atlas.

Lateral atlantoaxial joint:
-superior articular facets of axis articulate with inferior articular facets of atlas.

Front 27

Movements at joints

Back 27

Medianatlantoaxial joint (pivot or trochoidal joint):
-rotation of head and atlas around dens of axis as in shaking the head NO.

Atlanto-occiptal joints:
-slight movement of head forward and back as in nodding head YES.

Lateral atlantoaxial joints:
-movements similar to that of lower cervical vertebral joints C2-C7.

Front 28

Prevertebral Muscles

Back 28

-From the cervical transverse processes to ribs 1 and 2
-anterior and middle scalene mm. to ribs 1 form an interscalene cleft between the two mm. that encloses the brachial plexus and subclavian artery.

Front 29

Prevertebral Fascia

Back 29

Covers cervical sympathetic trunk/ganglia and Longus Colli m.

Front 30

Scalene mm.

Back 30

Innervation: Ventral rami of cervical spinal nerves

Action: Flex and lateral flex neck.

Front 31

Longus Colli m.

Back 31

-located on anterior aspect of cervical column
-guide to locating sympathetic trunk and ganglia

Front 32

Longus capitis m.

Back 32

Similar to longus colli m. except it attaches to the skull.