Neck and oral cavity Flashcards
Boundaries and functions of the oral cavity
Boundaries:
Superiorly- Nasal cavity
Inferiorly- Pharynx
Functions:
- Digestion
- Speaking [manipulation of sound from the larynx]
Divisions of the tongue
Oral division
- Anterior 2/3
Pharyngeal
- Posterior 1/3
Terminal sulcus divided anterior from posterior.
Papillae
- Contains taste buds
- Except filiform
Frenulum
Under medial fold that separates the right side from the left side of the tongue.
Divisions of the oral cavity
Oral vestibule
- Space between the lips and cheek
Oral cavity proper
- Space enclosed by the teeth
Boundaries of the oral cavity proper
Roof
- Hard and soft palate
Floor
- Mylohyoid muscle
- Geniohyoid muscle
- Tongue
- Submandibular and sublingual glands
Intrinsic muscles of the tongue
- Function
Longitudinal
Transverse
Vertical
Function:
- Fine movement of the tongue
- Used for speech, eating and swallowing.
Extrinsic muscles of the tongue [4]
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
Genioglossus
- Shape
- Function
Extrinsic muscle of the tongue
- Fan shaped
- Arising from the mandible
Action
- Depression
- Protrusion
Hyoglossus
- Shape
- Function
Extrinsic muscle of the tongue
- From hyoid bone
- Vertical fibres
Action:
Depression
Styloglossus
- Shape
- Function
Extrinsic muscle of the tongue arising from the styloid process
- Downwards, forward fibres
Function:
Retraction
Palatoglossus
- Shape
- Function
Extrinsic muscle arising from the soft palate
- downward fibres
Function:
- Elevates back of the tongue
- Depresses soft palate
Innervation of the oral tongue
Special afferent [TASTE]
- Chorda tympani [from CN7]
- Lingual nerve [from mandibular nerve]
General sensation
- Lingual nerve
Innervation of the pharyngeal division of the tongue
Special afferent [TASTE]
- Glossopharyngeal [CN9]
Sensation
- CN9
Motor
- Hypoglossal [CN12]
- CNX [palatoglossus]
Innervation of the muscles of the tongue
CN12
- Hypoglossus
CN10
- Vagus
- Palatoglossus ONLY
Venous and arterial supply to the tongue
- Source
Lingual arteries and veins
- Branch from the ECA
Muscles of the soft palate
Palatoglossal and Palatopharyngeal
- Form the arches
Uvula
All depress the palate
Hypoglossal nerve
- Type
- Exit
- Innervation
CN 12
- Exits hypoglossal canal
Gives all motor supply to the tongue
- Except palatoglossus muscle
Clinical test for CN12 function
Patient is asked to protrude their tongue
- A deviation to one side may indicate impairment of CN12
CN 9
- Name
- Exit
- Type [4}
- Innervation [5]
Glossopharyngeal
- Exits jugular foramen
Type
- Somatic sensory [oropharynx and posterior 1/3 of the tongue]
- Special afferent, taste [post. third of the tongue]
- Visceral—> parotid gland
- Motor—> Stylopharyngeus
Larynx
- Function
- Border
Phonation
- Sits above the trachea
- Hyoid bone superior
Sphincter for the airway, blocks objects from entering trachea
Larynx cartilages + their functions [6]
- I see see see Three A Es
Thyroid
- Forms Adam’s apple
- Connects to hyoid bone via ligament
Cricoid
- Forms inferior wall
- Connects to thyroid cartilage
Corniculate [paired]
- Apex of arytenoid
Arytenoid [paired]
- Alters vocal chords
Cuneiform [paired]
- anterior to corniculate
Epiglottis
- Elastic
- Blocks airway from food
Ligaments of the larynx
Vestibular
Vocal
Innervation of the larynx
Vagus nerve
- Recurrent laryngeal branch [motor]
- Superior laryngeal branch [sensory]
Arterial supply to the larynx
Upper half
- Superior thyroid [ from external carotid}
Lower half
- Inferior thyroid [ from thyrocervical trunk]
Pharynx divisions
- Surrounding anatomy
Pharynx [most posterior of neck]
- Behind oral cavity and nasal cavity
- Above oesophagus and larynx
Visions
- Nasopharynx
- Oropharynx
- Laryngopharynx
Muscles of pharynx
Superior, middle and inferior pharyngeal constrictor muscles
Innervation of pharynx
Motor
- CN X, Vagus
- Stylopharyngeus —->
CN 9, Glossopharyngeal
Sensory
- CN V2 [maxillary]
- CN 9
- CN X
General motor supply of the vagus nerve
Palatoglossus muscle
Larynx and Pharynx muscles
Path of vagus nerve
Medulla---> Jugular foramen [exit]--> Carotid sheath ---> Head + thorax----> Foregut and midgut
CN 8
- Name
- Exit
- Type
- Innervation
Vestibulocochlear
- Exits internal acoustic meatus
Sensory divisions:
- Vestibular [balance]
- Cochlear [hearing]
Special somatic afferent
- Carries information about hearing, equilibrium and motion
CN 11
- Name
- Exit
- Type
- Innervation
Accessory nerve
- Exits jugular foramen
Motor supply to:
- Sternocleidomastoid
- Trapezius
Fascias of the neck
- Clinical importance
Pretracheal
Prevertebral
Investing
Fascia reduce infection spread
Also allows structures to move past each other when the neck moves or during swallowing.
Carotid sheath
- Contents [6]
Fascia in the neck
Contains:
- Internal jugular vein
- Vagus nerve
- Deep cervical lymph nodes
- Carotid sinus nerve
- Common carotid
- Internal carotid
Bones of the neck
7 cervical vertebrae posteriorly
Hyoid bone anteriorly
Contents of the carotid triangle [5]
Common carotid artery
Internal jugular vein
CN 10-12
Boundaries of the carotid triangle [4]
Omohyoid
Stylohoid
Digastric muscle
Sternocleidomastoid muscle
Contents of the submandibular triangle [3]
Submandibular gland
Facial artery
Facial vein
Boundaries of the submandibular triangle
Anterior and posterior bellies of the digastric muscle
- Bound it at the front and back
Submental triangle contents and boundaries
Contents
- Lymph nodes
Bounded by anterior belly of the digastric muscle.
Muscular triangle
- Contents
- Boundaries
Contains:
Supra hyoid muscle
Infra hyoid muscle.
Boundaries:
- Omohyoid
- Sternocleidomastoid
Anterior trinangle
Region of the neck
- Separated from the lateral triangle by the sternocleidomastoid
Contains 3 paired triangles
- Submandibular
- Submental [unpaired]
- Muscular
- Carotid
Suprahyoid muscles of the muscular triangle
Stylohyoid
Digastric
Mylohyoid
Geniohyoid
Infrahyoid muscles of the muscular triangle
+ innervation
Innervation: C1-3 of ansa cervicalis
Omohyoid
Sternohyoid
Thyrohoid
Sternothyroid
Innervation of stylohoid and posterior digastric
Facial nerve [CN 7]
Mylohyoid innervation
CN 5
Geniohyoid innervation
CN 12
Posterior/ Lateral triangle
- Boundaries of traingles
Occipital triangle
- Sternocleidomastoid
- Trapezius
- Omohyoid
Supraclavicular triangle
- Clavicular SCM
- clavicle
- omohyoid
Posterior/ Lateral triangle contents [5]
Subclavian artery
External jugular vein
Brachial plexus
CN 11 [accessory]
Cervical plexus
Arterial supply of the neck
External carotid branches:
- Superficial temporal
- Maxillary
- Facial
- Ascending pharyngeal
- Superior thyroid
- Lingual
Subclavian branch
- Inferior thyroid
Venous drainage of neck
Internal jugular vein
- Neck viscera
- Neck muscles
External jugular
Anterior jugular
- connects to external jugular
Uvula innervation
CN X
