T2 L2 Neck & oral cavity Flashcards
Where is the oral cavity located?
Inferior to the nasal cavities
Continuous with both the nasal cavities superior & pharynx inferiorly
What does the outer oral vestibule include?
The lips & cheeks
What does the roof include?
The hard & soft palate
What forms the floor of the oral cavity?
Muscles (mylohyoid & geniohyoid) & the tongue
Contains submandibular & sublingual glands
What is the tongue divided into?
An anterior 2/3 (oral)
Posterior 1/3 (pharyngeal)
Demarked by a V-shaped sulcus
What does the undersurface of the tongue contain?
Medial fold which internally separates the right & left sides of the tongue
What are the intrinsic muscles of the tongue?
Longitudinal
Transverse
Vertical
What do the intrinsic muscles of the tongue do?
Movement for speech, eating & swallowing
What are the extrinsic muscles of the tongue?
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
What is the function of the genioglossus?
Depresses & protrudes tongue
What is the function of the hyoglossus?
Depresses tongue
What is the function of the styloglossus?
Retracts tongue
What is the function of the palatoglossus?
Elevates back of tongue
Depresses sift palate
What are the arteries & veins of the tongue?
Lingual arteries
Drains into lingual veins
Describe the innervation for the anterior 2/3rds of the tongue
Taste - special afferent (taste), facial nerve VII via chorda tympani via lingual nerve (V3)
Sensation - general sensation by lingual nerve (V3)
Describe the innervation for the posterior 1/3 of the tongue
Taste - special afferent (taste) by glossopharyngeal
Sensation - general sensation glossopharyngeal
Describe the motor innervation to the whole tongue
Hypoglossal nerve
Exception is palatoglossus which is supplied by CN X
What is the type &; exit of cranial nerve IX (glossopharyngeal)?
Type: sensory (somatic), special sensory (taste), motor & visceral
Exit: jugular foramen
Describe cranial nerve IX innervation
Sensory - posterior 1/3 of tongue, oropharynx
Taste - posterior 1/3 of tongue
Motor - stylopharyngeus muscle
Visceral to parotid gland to stimulate secretion to aid digestion
What are the submandibular & sublingual glands innervated by?
Facial nerve
What is the type & exit of cranial nerve XII (hypoglossal)
Type - motor to intrinsic & extrinsic muscles of the tongue
Exit - hypoglossal canal
What is the function of the larynx?
Protective sphincter for air passages & produces phonation
What cartilages make up the larynx?
Thyroid Cricoid Arytenoid Cuneiform Corniculate Epiglottis
What are the 2 most important ligaments in the larynx?
Vestibular
Vocal
What is the nerve supply to the larynx?
Sensory &motor from the vagus via the superior laryngeal branch & recurrent laryngeal branch
What is the blood supply to the larynx?
Upper 1/2 by superior thyroid artery
Lower 1/2 by inferior thyroid artery
Where is the pharynx located?
Most posterior part of the next
Behind nasal cavity & larynx
What are the 3 sections of the pharynx?
Nasopharynx
Laryngopharynx
Oropharynx
What are the muscles of the pharynx?
3 constrictors
Super, middle, inferior
What is the nerve supply to the pharynx?
Motor via vagus
Exception is stylopharyngeus which is supplied by CN IX.
Sensory via V2, CN IX, CN X
What is the type & exit of cranial nerve X?
Type: sensory, taste, visceral sensory, motor & visceral motor
Exit: jugular foramen
What is the path of cranial nerve X?
Rootlets from medulla through jugular foramen.
Continues in carotid sheath
Branches into head & thorax
What is the innervation of CN X?
Sensory: from larynx, dura mater
Taste: epiglottis & pharynx
Visceral sensory: aortic bodies, aortic arch chemoreceptors, bronchi, heart, lungs, midgut & foregut
Motor: palatoglossus, muscles of pharynx & larynx
Visceral motor: as part of parasympathetic to smooth muscle in glands in pharynx, larynx, thoracic viscera, foregut & midgut
What supports the neck?
Posteriorly by 7 cervical vertebrae
Where are the mobile hyoid bones located?
In the neck
What are the 3 layers of deep fascia in the neck?
Pretracheal fossa
Prevertebral fascia
Investing fascia
Why is the fascia in the neck important?
Reduce spread of infection
Enables structures to move past each other in movement & swallowing
What does the carotid sheath contain?
Common & internal carotid arteries Internal jugular vein Vagus nerve X Deep cervical lymph nodes Carotid sinus nerve
What are the 4 triangles in the anterior compartment?
Unpaired submental triangle
Paired submandibular
Paired carotid
Paired muscular triangle
What divides the posterior triangle of the neck?
The presence of the posterior belly of omoyhyoid
What is the posterior compartment of the neck divided into?
Large occipital triangle
Smaller ornoclavicular triangle
What are the boundaries & contents of the submandibular triangle?
Boundaries: anterior & posterior bellies of digastric
Contains: submandibular gland, facial artery & vein
What are the boundaries & contents of the submental triangle?
Bounded by digastric
Contains lymph nodes
What are the boundaries & contents of the muscular triangle?
Boundaries: omohyoid, SCM
Contains: supra & infra hyoid muscles
What are the boundaries & contents of the carotid triangle?
Boundaries: omohyoid, stylohyoid, digrastic, SCM
Contains: common carotid artery, IJV, hypoglossal nerve, vagus nerve, accessory nerve
What is the muscular triangle divided into?
Suprahyoid muscle
Infrahyoid muscle
What are the suprahyoid muscles?
Stylohyoid
Digastric
Mylohyoid
Geniohyoid
What is the innervation of the suprahyoid muscles?
Facial nerve for stylohyoid & posterior belly of digastric
Mylohyoid by CN V
Geniohyoid by CN XII
What are the infrahyoid muscles?
Omohyoid
Sternohyoid
Thyrohyoid
Sternothyroid
What is the innervation of the infrahyoid muscles?
C1-C3 of ansa cervicalis
What does the posterior triangle contain?
Subclavian artery
External jugular vein
CN XI
Cervical plexus
What is the occipital triangle bound by?
SCM
Trapezius
Omohyoid
What is the supraclavicular triangle bound by?
Clavicular head of SCM
Clavicle
Omohyoid
What does the brachiocephalic artery divide into?
Common carotid which divide into internal & external carotids
What does the external carotid divide into?
Superior thyroid Ascending pharyngeal Lingual Facial Maxillary Superficial temporal
What does the subclavian artery divide into?
Inferior thyroid
What is the venous drainage of the head & neck?
Internal jugular vein drains brain, face, cervical viscera & neck muscles
External jugular vein
Anterior jugular vein
What is the type & exit of cranial nerve XI (accessory)?
Type: motor to sternocleidomastoid & trapezius
Exit: jugular foramen
What is the type & exit of cranial nerve VIII (vestibulocochlear nerve)?
Type: sensory, special somatic, afferent for hearing, equilibrium & motion
Exit: internal acoustic meatus
What is the path of cranial nerve VIII?
Divides into vestibular & cochlear nerves