S1B5 - Craniovertebral Joints / Pharynx Flashcards
What joints are responsible for the ‘yes’ movement (nodding yes)? What is the ROM of that movement at those joints?
Atlanto-occipital (AO) joints
- ‘Yes’ movement (~45 degrees each direction)
What bony structures articlate in the atlanto-occipital joints?
Atlanto-occipital (AO) joints
- Synovial joints (condyloid) between occipital condyles and facets on superior surfaces of the lateral masses of the atlas.
At the atlanto-occipital joints, which structures are concave and which are convex?
Atlanto-occipital (AO) joints
- Occipital condyles are convex with complementary concave facets on the atlas
What are the primary movements allowed by the atlanto-occipital joints?
Atlanto-occipital (AO) joints
- Primarily allows flexion and extension.
- Slight rotation and lateral flexion can occur with a bit of ‘dislocation’
How many synovial joints are in the atlanto-axial joints? How many ligamentous articulations?
Atlanto-axial (AA) joints
- Three total synovial joints between the atlas and axis vertebrae plus one ligamentous articulation which create a composite structure allowing for rotation.
What structures form the lateral atlanto-axial joints? How are they oriented?
Atlanto-axial (AA) joints
- Inferior articular facets of the atlas and superior articular facets of the axis form the two lateral atlanto-axial joints (planar). These facets are large and transversely oriented allowing for a large amount of mobility
What structures articulate in the medial atlanto-axial joint? What kind of joint is it? How many joint cavities are there?
Atlanto-axial (AA) joints
- The medial atlanto-axial joint (pivot) is the articulation between the odontoid process (dens) of the axis and the anterior arch of the atlas AND between the odontoid process and transverse ligament of the atlas completing a pivot joint with two joint cavities.
What joint is mainly responsible for the ‘no’ movement of the head? What is the ROM of this motion at this joint?
Atlanto-axial (AA) joints
- ‘No’ movement (shake head ~45 degrees each direction; ~63 degrees = facet dislocation)
What craniovertebral ligament is a continuation of the anterior longitudinal ligament?
Anterior atlanto-occipital membrane
- continuation of the anterior longitudinal ligament
What does the anterior atlanto-occipital membrane connect?
Anterior atlanto-occipital membrane
- continuation of the anterior longitudinal ligament
- connects the anterior arch of atlas and anterior margin of foramen magnum
What cranio-vertebral ligament is in the same relative position as the ligamentum flavum?
Posterior atlanto-occipital membrane
- in same relative position as the ligamentum flavum
What does the posterior atlanto-occipital membrane connect?
Posterior atlanto-occipital membrane
- connects the posterior arch of atlas and posterior margin of foramen magnum
What artery pierces the posterior atlanto-occipital membrane?
Posterior atlanto-occipital membrane
- inferior margin is perforated by the vertebral artery
What craniovertebral ligament is pierced by the vertebral artery?
Posterior atlanto-occipital membrane
- inferior margin is perforated by the vertebral artery
Which CV ligament is a continuation of the posterior longitudinal ligament?
Tectorial membrane
- continuation of posterior longitudinal ligament
What does the tectorial membrane connect?
Tectorial membrane
- connects the body of the axis and anterior margin of foramen magnum to clivus
What other CV ligaments does the tectorial membrane cover?
Tectorial membrane
- covers the deeper cruciate, alar and apical ligaments
What is the strong transverse part of the cruciate (cruciform) ligament attached to?
Cruciate (cruciform) ligament
- has a strong transverse part attached to the lateral masses and anterior arch of atlas posterolateral to the odontoid process (dens)
What joint does the cruciate (cruciform) ligament help form?
Cruciate (cruciform) ligament
- helps form the medial atlanto-axial joint
What is the weak vertical part (longitudinal bands) of the cruciate (cruciform) ligament attached to?
Cruciate (cruciform) ligament
- has a weak vertical part (longitudinal bands) interconnects the body of the axis and the anterior margin of foramen magnum.
What is the alar ligament connected to?
Alar ligament (left and right)
- strong connections between the lateral sides of the odontoid process of C2 and the margin of the foramen magnum of the occipital bone
What is the functional role of the alar ligament?
Alar ligament (left and right)
- minimize rotation
What is the apical ligament connected to?
Apical ligament
- weak interconnection between the tip of dens and the margin of the foramen magnum of the occipital bone
What are the characteristics of a Jefferson’s (Burst) fracture?
Jefferson’s (Burst) fracture
- the arches of the atlas are fractured and the lateral masses are displaced laterally
What is the mechanism of injury for a Jefferson’s (Burst) fracture and what is a common example?
Jefferson’s (Burst) fracture
- usually due to excessive axial compression resulting in 2-4 fracture points or severe hyperextension resulting in posterior arch fractures
- diving into shallow water
What is fractured in a Hangman’s fracture?
Hangman’s fracture
- fracture of the pedicles of the axis (pars interarticularis)
What is the most common mechanism of injury for a Hangman’s fracture and what are common examples?
Hangman’s fracture
- due to force when neck is hyperextended is most common mechanism
- MVA’s or hangings
Hangman’s fractures are what percentage of all spinal fractures?
Hangman’s fracture
- 20% of all spinal fractures
What CV ligament is commonly ruptured with a fracture of the dens?
Fracture of the dens
- displacement of dens with or without rupture of the transverse ligament
What is the most common mechanism of injury for a fracture of the dens?
Fracture of the dens
- most commonly due to flexion-loading (anterior displacement) but may be due to extension loading yielding posterior dens displacement
The following is a desctiption of what anatomical structure?
- is a half-tube of striated muscle , incomplete/open anteriorly
The pharynx
- is a half-tube of striated muscle , incomplete/open anteriorly
What are the general functions of the pharynx?
The pharynx
- generally functions to funnel air, food, and fluids toward the larynx and esophagus while also aiding in vocalization and middle ear cavity pressure regulation.
The pharynx communicates with what three structures to cerat what three subdivisions of the pharynx?
The pharynx
- is located posterior to and communicates with the:
- nasal cavity (nasopharynx)
- oral cavity (oropharynx)
- larynx (laryngopharynx)
What is the spacial relationship between the pharynx and the vertebral column?
The pharynx is located anterior to the vertebral column (separated by fascia and space).
What are the superior and inferior attachments of the pharynx?
The pharynx extends from the base of the skull at the sphenoidal body to the esophagus.
At what level to the esophagus and trachea start?
Esophagus and trachea start at the same level (C6; inferior border of cricoid)
What are the two main muscular divisions of the pharynx?
The pharynx consists of outer circular muscle, inner longitudinal muscle and inner & outer layers of fascia.
What is the name of the ring of lymphoid tissue that guards the pharynx?
The pharynx is guarded by a ring of lymphoid tissue (tonsils; Waldeye’s Ring).
What provides motor innervation to the pharynx?
The pharynx has motor innervation primarily by the vagus nerve (one motor from glossopharyngeal n.).
What nerves provide sensory innervation to the pharynx?
The pharynx has sensory innervation via branches of the maxillary, glossopharyngeal and vagus nerves.
What are the three outer layer muscles of the pharynx? What is their posterior attachment?
The outer muscle layer is circularly oriented (half-circle) and consists of superior, middle and inferior constrictors that fuse at the midline posteriorly at one long continuous raphe.
What are the anterior attachments of the superior constrictor muscle? What other muscle is it continuous with?
Superior constrictor
- arises anteriorly form the pterygoid hamulus and pterygomandibular raphe, where it is continuous with the buccinator
What are the posterior attachments of the superior constrictor muscle?
Superior constrictor
- attached posteriorly to the pharyngeal tubercle at the base of the skull and to the pharyngeal raphe at the midline
What are the contents of the gap in the superior constrictor musculature at the base of the skull between its anterior and posterior attachment sites?
Superior constrictor
- there is a gap in the musculature at the base of the skull between its anterior and posterior attachment sites, filled in by pharyngobasilar fascia and providing a site of passage for the levator veli palatini, pharyngotympanic tube and ascending palatine artery to the inside of the pharynx
What are the anterior attachments of the middle constrictor muscle?
Middle constrictor
- arises anteriorly from the lesser and greater horns of the hyoid bone and the lower part of the stylohyoid ligament
What is the posterior attachment of the middle constrictor muscle?
Middle constrictor
- attaches posteriorly to the pharyngeal raphe
Describe the posterior overlap between the middle and superior constrictor muscles.
Posteriorly, the upper fibers of the middle constrictor overlap the lower fibers of the superior constrictor, like stacked cups.
What are the contents of the anterior gap between the middle and superior constrictors?
Anteriorly, there is a gap between the middle & superior constrictors allowing for the passage of the stylopharyngeus, stylohyoid ligament and glossopharyngeal n (IX).
What is the posterior attachment of the inferior constrictor muscle?
Inferior constrictor
- attaches posteriorly to the pharyngeal raphe
Describe the posterior overlap of the inferior and middle constrictor muscles.
Posteriorly, the upper fibers of the inferior constrictor overlap the fibers of the middle constrictor & perhaps as superior as the superior constrictor.
What are the contents of the anterior gap between the middle and inferior constrictor muscles?
Anteriorly, the gap between the middle and inferior constrictor muscles permits the passage of the internal laryngeal nerve and superior laryngeal artery.
What do the lower fibers of the inferior constrictor form?
The lower fibers of the inferior constrictor form the cricopharyngeus that acts as a sphincter between the pharynx and esophagus.
What is the result of posterior weakness of the cricopharyngeus?
the lower fibers of the inferior constrictor form the cricopharyngeus that acts as a sphincter between the pharynx and esophagus
NOTE: posterior weakness –> Killian’s Dehiscence (pharyngeal pouch);
if the mucous membrane herniates –> pharyngeal diverticulum, usually to the left side
What happens if the mucous membrane of the cricopharyngeus herniates?
the lower fibers of the inferior constrictor form the cricopharyngeus that acts as a sphincter between the pharynx and esophagus
NOTE: posterior weakness –> Killian’s Dehiscence (pharyngeal pouch);
if the mucous membrane herniates –> pharyngeal diverticulum, usually to the left side
What structures enter the larynx at the lower border of the cricopharyngeus?
The recurrent laryngeal nerve and inferior laryngeal artery enter at the lower border of the cricopharyngeus
What are the three primary internal muscles of the pharynx?
The internal muscles of the pharynx are arranged longitudinally and consist of
- Salpingopharyngeus
- Palatopharyngeus
- Stylopharyngeus
What does salpingopharyngeus arise from?
Salpingopharyngeus
- arises from the pharyngotympanic tube (cartilaginous portion of)
- blends in with the posterior wall of the pharynx
What does Salpingopharyngeus blend with?
Salpingopharyngeus
- arises from the pharyngotympanic tube (cartilaginous portion of)
- blends in with the posterior wall of the pharynx
What does palatopharyngeus arise from and what does it blend with?
Palatopharyngeus
- arises from the hard palate and aponeurosis
- blends with the side of the pharyngeal wall
What are the attachments of stylopharyngeus?
Stylopharyngeus
- arises from the styloid process (then between superior and middle constrictors)
- attaches inferiorly to the upper border of the thyroid cartilage
What two outer pharyngeal muscles does stylopharyngeus run between?
Stylopharyngeus arises from the styloid process (then between superior and middle constrictors)
What is the motor innervation of stylopharyngeus?
Stylopharyngeus is the only muscle of the pharynx that is not innervated by the vagus, but by the glossopharyngeal nerve.
What is the name of the thin layer of loose connective tissue that forms the outer covering of the pharynx?
Buccopharyngeal fascia
- thin layer of loose connective tissue that forms the outer covering of the pharynx
- the pharyngeal plexus of nerves are embedded in this fascia
What is embedded in the buccopharyngeal fascia?
The pharyngeal plexus of nerves are embedded in the buccopharyngeal fascia.
What is the name of the connective tissue that fills in the gap between the upper borders of the superior constrictors and the base of the skull?
Pharyngobasilar fascia
- fills in the gap between the upper borders of the superior constrictors and the base of the skull
What branches of the facial artery help supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
What branches of the maxillary artery help supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
What branch of the inferior thyroid artery helps supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
What branches of the inferior thyroid artery help supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
Do branches of the superior thyroid artery help supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
What do the veins of the pharynx flow into?
Veins of the pharynx form a minor plexus that drains into the pterygoid plexus of veins and other sites.
What vessel is responsible for most of the bleeding in the removal of the palatine tonsils (tonsillectomies)?
The external palatine vein is the source of much of the bleeding in the removal of the palatine tonsils (tonsillectomies).
What is the primary innervation of the pharynx?
Innervation of the pharynx is primarily via the pharyngeal plexus (found in buccopharyngeal fascia) that contains motor fibers from the vagus and sensory fibers from the glossopharyngeal nerves.
What branch of the external carotid artery helps supply the pharynx?
Numerous arteries supply the pharynx and tonsillar regions. These include…
- external carotid artery –> Ascending pharyngeal artery
- facial artery –> Ascending palatine artery and Tonsillar artery
- maxillary artery –> Descending palatine artery and a Pharyngeal branch
- inferior thyroid artery –> Pharyngeal branches
- Branches from superior thyroid artery (know this, just not shown here)
What nerves provide motor innervation to the muscles of the pharynx?
Motor
- All muscles of the pharynx are innervated by the vagus nerve, except stylopharyngeus
- Stylopharyngeus is innervated by the only muscular branch of CN IX.
What nerve receives sensory information from the upper part of the nasopharynx?
The upper part of the nasopharynx (adenoids) receives sensory innervation from the maxillary nerve.
What nerve receives sensory information from the lower part of the pharynx?
The lower part is innervated by sensory fibers of the glossopharyngeal nerve.
What is the sensory nerve of the gag reflex? What is the motor nerve of the gag reflex?
In the gag reflex, the sensory nerve is the glossopharyngeal, and the motor nerve is the vagus.
Where does most lymphatic drainage from the pharynx and tonsils drain to?
Most lymphatic drainage from the pharynx, including the tonsils, is mostly to the jugulodigastric (tonsillar) nodes.
What 3 spaces is the interior of the pharynx divided into?
Interior of the pharynx is divided into 3 spaces; the nasopharynx, oropharynx and laryngopharynx.
What are the boundaries of the nasopharynx?
Nasopharynx
- Boundaries
- superior is the body of the sphenoid
- continuous with the nasal cavities via the choanae (ko-ah-knee; funnel)
- separated inferiorly from the oropharynx by the soft palate
In which interior division of the pharynx is the opening of the pharyngotympanic (auditory/eustachian) tube found?
Nasopharynx
- contents
- the opening of the pharyngotympanic (auditory/eustachian) tube
What is the name for the bulge that the cartilage of the pharyngotympanic tube forms? In what interior pharynx division is this located?
Nasopharynx
- Contents
- the cartilage of the pharyngotympanic tube forms a bulge called the torus tubarius (tubal elevation; torus = swelling)
What muscle does the salpingopalatine fold contain? In which interior pharynx division is this located?
Nasopharynx
- Contents
- the salpingopharyngeal fold, contains the salpingopharyngeus muscle and extends inferiorly and posteriorly from the pharyngotympanic tube (salpinx = trumpet-like tube)
What interior pharynx division contains the salpingopalatine fold?
Nasopharynx
- Contents
- the salpingopalatine fold overlies the tensor veli palatini muscle
- TVP modifies the auditory tube for air exchange)
- TVP hooks under pterygoid Hamulus
- TVP – V3 and otic ganglion sit on it
- the salpingopalatine fold overlies the tensor veli palatini muscle
What muscle does the salpingopalatine fold overlie?
The salpingopalatine fold overlies the tensor veli palatini muscle.
What is the functional role of the tensor veli palatini muscle?
The tensor veli palatini muscle modifies the auditory tube for air exchange
What structure does the tensor veli palatini hook under?
Tensor veli palatini muscle hooks under pterygoid Hamulus.
What neural structures sit on the tensor veli palatini muscle?
V3 and otic ganglion sit on the tensor veli palatini muscle.
What are the attachments of the levator veli palatini muscle?
Levator veli palatini attaches between petrous temporal and auditory tube to palatine aponeurosis.
What is the pharyngeal recess? In what interior pharynx division is it located?
Nasopharynx
- Contents
- the pharyngeal recess is a slit-like space that extends posteriorly and laterally behind the torus tubarius
Where in the pharynx are the pharyngeal tonsils located?
The roof and posterior wall of the nasopharynx contains the pharyngeal tonsils (adenoids).
What are the boundaries of the oropharynx?
Oropharynx
- Boundaries
- separated from the oral cavity by the tongue and the palatoglossal and palatopharyngeal arches
- separated from the nasopharynx superiorly by the soft palate
- extends inferiorly to the superior border of the epiglottis
What is the name of the space between the palatoglossal arch (anterior pillar) and palatopharyngeal arch (posterior pillar)?
What does this contain?
In what interior division of the pharynx is this located?
Oropharynx
- Contents
- the space between the palatoglossal arch (anterior pillar) and palatopharyngeal arch (posterior pillar) forms the tonsillar cleft and contains the palatine tonsils
Tonsilar bed:
- What interior division of pharynx?
- What tonsils are in it?
- What muscle is in it?
Oropharynx
- Contents
- the tonsillar bed, which the palatine tonsil occupies, is formed by the pharyngobasilar fascia and the superior constrictor muscle
What is the name of the large accumulation of lymphoid tissue at the base of the tongue facing the pharynx?
Oropharynx
- Contents
- the base of the tongue facing the pharynx contains a large accumulation of lymphoid tissue forming lingual tonsils.
What is the spacial relationship between the laryngopharynx and the larynx?
Laryngopharynx lies posterior to the larynx.
What are the superior and inferior reaches of the laryngopharynx?
Laryngopharynx extends from the superior border of the epiglottis to the inferior border of the cricoid cartilage.
What two structures does the laryngeal inlet allow communication between?
Laryngopharynx communicates with larynx through the laryngeal inlet.
Food can get trapped here and ‘stimulate’ the recurrent & internal laryngeal nerves found under mucosa.
The piriform recess is on either side of the larynx extending to the laminae of the thyroid cartilage (food can get trapped here and ‘stimulate’ the recurrent & internal laryngeal nerves found under mucosa).
What are the names of the folds of mucosa connect the base of the tongue to the epiglottis?
Folds of mucosa connect the base of the tongue to the epiglottis, forming the midline medial glossoepiglottic fold and two lateral glossoepiglottic folds.
What is the name of the depression between the glossoepiglottic folds?
The depression between the glossoepiglottic folds form the valleculae.
What is Waldeyer’s ring? What is its functional role?
The pharyngeal tonsils, palatine tonsils and lingual tonsils along with smaller lymphoid masses form a ring of lymphoid tissue called Waldeyer’s ring that guard against infections.
If you want to sound smart, what word should you use for the act of swallowing?
Deglutition is the act of swallowing.
What are the three stages of deglutition?
Deglutition is the act of swallowing and has 3 stages
- as a voluntary act, the bolus of food is compressed between the palate and tongue to be pushed into the oropharynx by the tongue (particularly by styloglossus).
- involuntarily, the soft palate is elevated to seal the nasopharynx (via levator & tensor veli palatini) and the suprahyoid muscles and longitudinal pharyngeal muscles contract to elevate the larynx and force it against the base of the tongue, this also forces the epiglottis posteriorly against the pharyngeal wall and tipping it down.
- involuntarily, sequential contraction of the constrictors close the laryngeal aditus, closure of the rima glottides, and these contractions also propel food from the oropharynx into laryngopharynx and into the esophagus.
