Module 7b: The neck Flashcards
Pharynx
Fibromuscular tube that extends from the base of the skull to upper esophageal sphincter
What three constrictor muscles form the fibromuscular walls of the pharynx?
- Superior pharyngeal constrictor
- Middle pharyngeal constrictor
- Inferior pharyngeal constrictor
Upper esophageal sphincter
Formed by lower part of inferior constrictor muscle; prevents reflux of food into airway and prevents air from entering digestive tract
Divisions of pharynx
- Nasopharynx
- Oropharynx
- Laryngopharynx
Chonae of nasopharynx
How nasopharynx communicates with nasal cavity anteriorly
Lateral walls of nasopharynx
Openings to eustachian tubes
Roof of nasopharynx
Collection of lymphatic tissue (pharyngeal tonsil)
Pharyngeal isthmus
Allows for communication of nasopharynx w oropharynx
Oropharynx
Communicates anteriorly with oral cavity through the oropharyngeal isthmus
Fold of mucous membranes in oropharynx
- Palatoglossal arch
- Palatopharyngeal arch
Palatine tonsil
Located bwtn folds of oropharynx
Laryngopharynx
Extends from oropharynx to esophagus
Laryngeal inlet
Opens into anterior wall of laryngopharynx
Piriform recesses
Formed by cavity of laryngopharynx; extends anteriorly on each side of laryngeal inlet
Function of piriform recesses
Direct food from oral cavity to either side of laryngeal inlet, towards the esophagus
Choking
Blockage of upper airway by an object usually above the vocal folds
Symptoms of choking
Irregular breathing/coughing
High pitched wheezing/no breathing
Blue lips
Vestibular and vocal ligaments
Enclosed by respective folds (vestibular fold and vocal fold)
True vocal fold
Vocal fold
False vocal fold
Vestibular fold
Cricothyroid ligament
Originates from upper border of cricoid cartilage and extends superiorly where its upper margin forms vocal ligament
Arytenoid cartilage
Back of larynx, close vocal folds during swallowing and change tension of vocal cords for sound production
Action of vocal folds during respiration
Abduct vocal folds
Action of vocal folds during swallowing
Adduct vocal folds
Action of vocal folds during phonation
Partially adduct and alter tension of vocal folds
Phonation
Production of speech sounds
Intrinsic muscles of larynx function
Control shape of rima glottidis, and length and tension of vocal ligaments during breathing, swallowing and phonation
What are the intrinsic muscles of larynx?
- Thryoarytenoid
- Cricothyroid
Thyroarytenoid origin
Inferoposterior aspect of angle of thyroid cartilage
Thyroarytenoid insertion
Anterolateral part of arytenoid cartilage
Thyroarytenoid action
Relax vocal ligaments, produce softer voice
Thyroarytenoid innervation
Recurrent laryngeal nerve (branch of vagus)
Cricothyroid origin
Anterolateral aspect of cricoid cartilage
Cricothyroid insertion
Inferior margin of thyroid cartilage
Cricothyroid action
Stretches and tenses vocal ligaments for production of loud speech and diff tones of voice
Cricothyroid innervation
External laryngeal nerve (branch of superior laryngeal nerve)
Laryngospasm
Occurs when vocal folds suddenly sieze up due to disruption in nervous input from the laryngeal nerves, leads to airway obstruction
What are the triggers of a laryngospasm?
Asthma, allergies, exercises, irritants, stress and anxiety, GERD
Laryngospasms caused by GERD
Malfunctioning lower esophageal sphincter resulting in regurgitation of corrosive stomach contents into esophagus; nerves stimulated
Symptoms of laryngospasm
Choking sensation
Inability to breathe or speak
High pitched breathing noises (stridor)
Arterial supply of thyroid gland
Superior thyroid artery (branch of external carotid)
Inferior thyroid artery (branch of thyrocervical trunk of subclavian artery)
Venous supply of thyroid gland
Drained by superior, middle and inferior thyroid veins which form a venous plexus on anterior surface of thyroid gland and descends anterior to trachea
Where do the superior and middle thyroid veins drain into?
Internal jugular vein
Where does inferior thyroid vein drain into?
Brachiocephalic vein
Innervation of thyroid gland
Vagus nerve
Sympathetic trunk
Vagus nerve supply of thyroid gland
Superior laryngeal nerve and recurrent laryngeal nerve
Sympathetic trunk nerve supply of thyroid gland
Superior, middle and inferior cervical ganglia
Goiter
Abnormal enlargement of thyroid gland
Symptoms of goiter
Compression of cricothyroid altering speech
Compressed vagus nerve- difficulty breathing and swallowing
Compressed trachea- tightness in throat and unusual coughing
Compressed phrenic nerve- difficulty breathing
Superficial muscles of neck
- Sternocleidomastoid
- Platysma
Sternocleidomastoid origin
Manubrium and medial end of clavicle
Sternocleidomastoid insertion
Mastoid process
Sternocleidomastoid action
Flex head and neck, tilt and rotate head
Sternocleidomastoid innervation
Accessory nerve
Platysma origin
Upper 2 ribs
Platysma insertion
Lower margin of mandible
Platysma action
Tenses skin of neck, facial expression
Deep muscles of neck
- Scalenes
- Levator Scapulae
Scalenes
Three muscles in deep lateral neck, spanning btwn transverse processes of cervical vertebrae and ribs 1 and 2
Scalenes action
Flex and rotate neck, elevate ribs during forced expiration
Levator scapulae origin
Transverse processes of C1-C4
Levator scapulae insertion
Scapula
Levator scapulae action
Lift scapula and support vertebral column
Sternocleidomastoid syndrome causes
Stress, overuse, poor posture, inactivity
Symptoms of sternocleidomastoid syndrome
Pain in lateral neck, posterior head, jaw and throat
headaches
Neck stiffness
Tingling in face or neck
The hyoid bone
U-shaped bone superior to larynx, attached by thyrohyoid membrane
What bone doesn’t articulate with any other bones?
Hyoid bone
The supra-hyoid muscles
- Diagastric
- Stylohyoid
- Mylohyoid
- Geniohyoid
Diagastric posterior belly
Attaches to mastoid process
Nerve supply- facial nerve
Diagastric anterior belly
Attaches to mandible
Nerve supply- mandibular nerve
Stylohyoid origin
Styloid process of temporal bone
Stylohyoid insertion
Hyoid bone
Stylohyoid innervation
Facial nerve
Mylohyoid origin
Mandible
Mylohyoid insertion
Hyoid bone
(join together at midline raphe to form floor of mouth)
Geniohyoid origin
Mandible
Geniohyoid insertion
Hyoid bone
Posterior belly of digastric muscle strain cause
Overuse of misalignment
Symptoms of posterior belly of digastric muscle strain
Pain in neck and under chin
Referred pain to sternocleidomastoid
Trigger point of posterior belly of digastric muscle
Under angle of mandible
Trigger point of anterior belly of digastric muscle
Referred pain to lower front teeth
Infrahyoid muscles action
Depress hyoid bone and larynx during swallowing and phonation
Infrahyoid muscles
- Sternohyoid
- Omohyoid
- Thyrohoid
- Sternothyroid
Sternohyoid origin
Manubrium
Sternohyoid insertion
Hyoid bone
Omohyoid inferior belly origin
Scapula
Omohyoid inferior belly insertion
Intermediate tendon
Omohyoid superior belly origin
Intermediate tendon
Omohyoid superior belly insertion
Hyoid bone
Thyrohyoid origin
Thyroid cartilage
Thyrohyoid insertion
Hyoid bone
Sternothyroid origin
Manubrium
Sternothyroid insertion
Thyroid cartilage
Omohyoid muscle syndrome
Presents as a mass in the neck located superior to the clavicle that is only visible when the patient swallows
Symptoms of omohyoid muscle syndrome
Stiff neck
Tenderness when palpating near the mass
Causes of omohyoid muscle syndrome
Irritation or damage to muscle from excessive vomiting or neck trauma
Arterial supply of head
Internal and external carotid arteries (branches of common carotid)
Subclavian arteries
What do internal carotid arteries supply?
Brain and eyes
What do external carotid arteries supply?
Face and neck
Where does the left subclavian arteries arise from?
Aortic arch
Where does the right subclavian arteries arise from?
Brachiocephalic trunk
Venous drainage of head
Internal jugular veins
Subclavian veins
Internal jugular veins
Drain blood from brain and superficial regions of face and neck
Joins subclavian vein to form brachiocephalic vein
Subclavian veins
Used to place central venous lines
Atherosclerosis of internal carotid artery
Buildup of fats, cholesterol in arterial walls leading to narrowing and irregularity of artery’s lumen, prevent blood flow to brain
Symptoms of atherosclerosis of internal carotid artery
Dizziness
Headaches
Confusion
Fainting
Lymphatic drainage of neck
- Superficial nodes
- Cervical nodes
- Jugular trunk
- Thoracic and lymphatic trunk
Superficial nodes
Submental nodes
Submandibular nodes
Cervical nodes
Deep and superficial
Superficial cervical nodes
On surface of SCM and are associated w external jugular vein
Deep cervical nodes
Deep to SCM and closely related to internal jugular vein
Jugular trunk
All lymphatic vessels of head and neck drain into deep cervical nodes then into jugular nodes
Thoracic and right lymphatic trunk
jugular trunks empty into thoracic duct on left and right lymphatic trunk on right
Recurrent strep throat infection
Bacterial infection of pharynx
Symptoms of recurrent strep throat infection
Enlarged lymph nodes of neck
Pain when swallowing
Stiffness in neck
Headaches
Fever
Red palatine tonsils
Glossopharyngeal nerve (CN IX)
Sensory innervation to tongue, pharynx and middle ear
Hypoglossal nerve (CN XII)
Supplies muscles of tongue
Vagus nerve (CN X)
Forms vagus nerve plexus
Vagus nerve plexus
Gives rise to nerves that form pharyngeal, parasympathetic cardiac, pulmonary and esophageal plexuses
Forms superior laryngeal nerves
Right recurrent laryngeal nerve
Branch of right vagus nerve
Loops around right subclavian artery
Left recurrent laryngeal nerve
Branch of left vagus nerve
Loops around ligamentium arteriosum of arch of aorta
Innervation of recurrent laryngeal nerves
Intrinsic muscles of larynx and mucous membrane of larynx
Unilateral facial paralysis
Immobility of vocal folds due to damage or dysfunction of recurrent laryngeal or vagus nerve
Symptoms of unilateral face paralysis
Swallowing disability
Shortness of breath
Weak cough
Horseness of voice
What does the cervical plexus supply?
Supplies infrahyoid muscles
Innervation of thyrohyoid muscle
C1 via hypoglossal nerve
What forms the cervical plexus?
Ventral rami of cervical spinal nerves 1-4
What does the cervical plexus supply?
Motor innervation muscles of neck
Sensory innervation to skin of neck and back of scalp
Infra-hyoid muscle paralysis
Caused by trauma to cervical spine leading to damage of cervical plexus
Symptoms of infra-hyoid muscle paralysis
Difficulties swallowing
Horse voice
Tightness in thrort
Where does right phrenic nerve travel?
- Anterior to right subclavian artery
- Into thorax through thoracic inlet
- Anterior to root of right lung
- Along pericardium of right atrium
- Pierces diaphragm at opening of IVC
Where does left phrenic nerve travel?
- Anterior to left subclavian
- Into thorax through thoracic inlet
- Anterior to root of left lung
- Cross aortic arch and left vagus nerve
- Along pericardium of left ventricle
- Pierces and innervates diaphragm
Phrenic nerve damage symptoms
Difficulty breathing, shortness of breath, feeling faint
Phrenic nerve irritation
Hiccups
Three main sympathetic ganglia
- Superior cervical ganglion
- Middle cervical ganglion
- Inferior cervical ganglion
Superior cervical ganglion
Posterior to carotid arteries, anterior to C1-C2 vertebrae
Middle cervical ganglion
Anterior to thyroid artery and C6; might be absent in some people
Inferior cervical ganglion
Anterior to C7 vertebra
Horner’s syndrome
Disorder resulting from damage to sympathetic innervation of head; caused by spinal core lesions of tumour
Symptoms of horner’s syndrome
Drooping of upper eyelid
Constriction of pupil
Absence of sweating on face and neck
