The temporomandibular joint and neural control of chewing, mastication and swallowing Flashcards
Lowest part of costal margin 10th rib
L3
xiphersternum - T9
inferior angle of the scapula - T8
suprasternalnotoch - T2/3
angle of Louis - T4
trachea runs how far
C6-T5
does exercise dilate or constrict lungs
dilate due to sympathetic
ant, lat and post borders of the larynx
Anteriorly- infrahyoid muscles
Laterally- thyroid gland
Posteriorly -oesophagus
Identify and describe the subdivisions of the laryngeal cavity.
Supraglottis – From the inferior surface of the epiglottis to the vestibular
folds (false vocal cords).
Glottis – Contains vocal cords and 1cm below them. (The opening between
the vocal cords is known as rima glottidis, the size of which is altered by the
muscles of phonation.)
Subglottis – From inferior border of the glottis to the inferior border of the
cricoid cartilage.
the extrinsic muscles or the larynx do what
Extrinsic-elevate or depress the larynx during swallowing
comprised of
the suprahyoid and infrahyoid groups, and the
stylopharyngeus (a muscle of the pharynx).
The supra- and infrahyoid muscle groups attach to
the hyoid bone. This, in turn, is bound to the larynx by
strong ligaments; allowing the whole of the larynx to be
moved as one unit.
As a general rule, the suprahyoid muscles and the
stylopharyngeus elevate the larynx, whilst the
infrahyoid muscles depress the larynx.
the intrinsic muscles of the larynx do what
Intrinsic- move the individual components of the larynx, for breathing and
phonation
control shape of rima glottis
All internal muscles are innervated by the inferior laryngeal nerve (branch of
the recurrent laryngeal)
Except cricothyroid, which is innervated by the superior laryngeal nerve
Cricothyroid
Stretches and tenses the vocal ligaments, for forceful speech
Helps alter tone of voice (‘singer’s muscle’)
Attachments: cricoid cartilage to thyroid cartilage.
Thyroarytenoid
Relaxes the vocal ligament, for a soft voice
Attachments: thyroid cartilage to arytenoid cartilage.
Posterior cricoarytenoid
Abducts vocal folds, widens the rima glottidis.
Attachments: cricoid cartilage to arytenoid cartilage.
Lateral cricoarytenoid
Adductors of the vocal folds,narrows the rima glottides
(alters speech tone and volume)
Attachments: Cricoid cartilage to arytenoid cartilage
Transverse and Oblique Arytenoids
Adduct the arytenoid cartilages, closing the posterior portion of rima glottides, narrowing the
laryngeal inlet.
Attachments: From one arytenoid cartilage to the opposite
nerve supply of the larynx
The larynx receives both motor and sensory innervation via branches
of the vagus nerve:
Recurrent laryngeal nerve – provides sensory innervation to the
infraglottis, and motor innervation to all the internal muscles of
larynx (except the cricothyroid).
Superior laryngeal nerve – the internal branch provides sensory
innervation to the supraglottis, and the external branch provides
motor innervation to the cricothyroid muscle.
muscles of the pharynx and nerve supply
Main three muscles
Superior, middle &
inferior constrictors
Sensory: Glossopharyngeal
nerve (CN9)
Motor: Vagus (CN10)
Gag reflex
Which Extrinsic muscle of the tongue is not supplied by the hypoglossal nerve?
palatoglossus - vagus nerve
Genioglossus. Hyoglossus. Styloglossus. Palatoglossus. 4 extrinsic muscles
hypoglossal nerve does the motor function of the tongue
but what nerves do the sensory innervation to the tongue
lingual nerve ( CNV3) front 2/3 - gnarl sensory
chorda tympani ( CN7) special sensory to middle part
glossopharyngeal nerve does general and special sensory of the posterior 1/3
chorda tympani travels with facial nerve and comes through middle ear
internal laryngeal nerve (CN10) also does a bit of the posterio medial tongue
hypoglossal nerve does the motor function of the tongue
but what nerves do the sensory innervation to the tongue
lingual nerve ( CNV3) front 1/3 - gnarl sensory
chorda tympani ( CN7) special sensory to middle part
glossopharyngeal nerve does general and special sensory of the posterior 2/3
internal laryngeal nerve (CN10) also does a bit of the posterio medial tongue
muscles of mastication
masseter
temporalis
medial pterygoid
lateral pterygoid
pharyngeal arches and their cranial nerves
1- trgemnail 2- facial 3- glosso 4- vagus The tongue is innervated by five cranial nerves based on its embryological origin from the pharyngeal arches, namely: Vagus, Hypoglossal, Glossopharyngeal, Facial and Trigeminal.
temporalis
Elevates mandible in closing jaws
Retract mandible – posterior, more horizontal fibres
medial pterygoid
Elevates mandible in closing jaws – acting synergistically with masseter
Protrudes mandible – a contribution
Produces chewing/grinding movements – alternate unilateral action.
lateral pterygoid
Protracts/Protrudes mandible – acting bilaterally
Depresses chin – acting bilaterally
Swings jaw toward contralateral side – acting unilaterally
Produces larger lateral chewing/grinding movements – alternate unilateral contraction
all of the muscles of mastication supplied by what nerve
mandibular devision of the trigeminal
The muscles of mastication develop from the mesoderm of the embryonic first pharyngeal arch.
TMJ is a Modified Hinge type of Synovial Joint.
Formed by:
Mandibular fossa and
Articular tubercle of temporal bone, and
Head of mandible
ligaments include - sphenomandibular ligament
lateral ligament
stylomandibualr ligament
3 phases of swallowing
Voluntary Oral phase – Cerebral cortex control - V, (VII), IX, X & XII
Involuntary Pharyngeal phase, rapid – sensory receptors and swallowing centre in the medulla oblongata – triggers a reflex act (V, IX, X & XII). Respiration is momentarily stopped.
Involuntary Oesophageal phase – X, IX and sympathetic fibres – Peristaltic movement.
Involves coordinated function of muscles in the mouth, pharynx, larynx and oesophagus.
what nerves involved in swallowing
CN 4,7,9,10
Frontal gyrus
Precentral gyrus
what included in the common integration area
Common integration area: Integrates sensory information (about food size, temperature and texture) from: The mouth Pharynx Larynx
Sends orders to the swallowing reflex muscles including:
Muscles of mastication.
Intrinsic muscles of the tongue
Muscles involved in closing the larynx and moving epiglottis.
deglutination reflex
Sensory receptors in the oropharynx send signal to the deglutition (swallowing) centre in the brain stem.
Initiates motor activity mediated via the
V, IX, X and XII cranial nerves.
Effects muscle contraction:
elevates soft palate to close nasopharynx.
Moves the epiglottis, and elevates and closes off the larynx.
Initiates peristalsis of the pharynx and oesophagus.
Respiration is momentarily stopped during the pharyngeal phas
when is respiration momentarily stopped during swallowing
pharyngeal phase
pathway of the gag reflex
glossopharyngeal nerve tactiel sensation of posterior 2/3
this goes to brainstem - sensory nucleus of trig menial nerve
pathway of the gag reflex
glossopharyngeal nerve tactiel sensation of posterior 2/3
this goes to brainstem - sensory nucleus of trig menial nerve - nucleus ambiguous of vagus and hypoglossal nucleus - through fibres and then to muscles of soft palate and pharynx and upper part of oesophagus and stylopharyngeus - CN9
Pseudobulbar palsy, also known as involuntary emotional expression disorder, is a condition that affects your ability to control of the muscles in your face (including your jaw). The muscles in your mouth (i.e. your tongue) and your throat can also be affected. It can have a big impact on your everyday life.
Bulbar palsy is a set of conditions that can occur due to damage to the lower cranial nerves. Clinical features of bulbar palsy range from difficulty swallowing and a lack of a gag reflex to inability to articulate words and excessive drooling. Bulbar palsy is most commonly caused by a brainstem stroke or tumor.
`bulbar - LMN
pseudo- UMN
aspiration can cause pneumonia - what is the most common place does this occur in the lungs
right lower lobe
what can you use to tract food down the throat
barium
if person has difficulty swallowing , hoarse voice and vertigo with rapid onset
stroke of post cerebellar artery - laterally medulla or Wallenberg syndrome
45 yr old sliding mass in through on right side of neck and weight loss
supra glottis tumour - CT head and neck
hiatus hernia
stomach pushed through diaphragm
