The Pharynx 1

Question 1

To see the upper part of the pharynx, what structures of the lower face must be removed?

Answer 1

• ramus of the mandible + associated
• parotid salivary gland
• several vessels and cranial nerves

Question 2

What is the pharynx?

Answer 2

It is a muscular tube.

Question 3

Where do the upper fibres of the pharynx arise from?

Answer 3

They arise from the back of the nose on either side, from the pterygoid plates of the sphenoid bone.

Question 4

What is the hamulus?

Answer 4

The lowermost tip of each medial pterygoid plate curves outwards like a hook.

Question 5

Where do the fibres of the pharynx that arise on either side of the medial pterygoid plates attach to?

Answer 5

They attach to the basioccipital bone at a point called the pharyngeal tubercule.

The fibres from medial pterygoid plate form a muscular tube which is part of the superior constrictor muscle and the upper part of the tube bounds the nasopharynx.

Question 6

What happens to the fibres of the pharynx in the midline posteriorly?

Answer 6

There is a seam/ raphe where the fibres from each side fuse with each other.

Question 7

Where else do muscle fibres of the superior constrictor muscle arise from?

Answer 7

They arise from lower down from the sides of the mouth just below the medial pterygoid plate. They come from another raphe called the pterygomandibular raphe.

Question 8

Where is the pterygomandibular gland?

Answer 8

This extends from the pterygoid hamulus to the inner surface of the mandible on each side of the mouth.

Question 9

What happens to the muscular fibres of the superior constrictor muscles that sweep posteriorly?

Answer 9

They fuse together again at the posterior midline raphe of the pharynx.

Question 10

Describe the posterior part of the superior constrictor muscle.

Answer 10

This part encircles the oropharynx at the back of the oral cavity. It has the palatine tonsil applied to its inner wall at the sides.

Question 11

Where is the origin of the muscle fibres of the middle constrictor muscle?

Answer 11

• greater horn of the hyoid bone
• stylohyoid ligament

Question 12

What is the path of the middle constrictor muscle?

Answer 12

• these fibres sweep round to the back of the pharynx
• run outside the lowermost fibres of the superior constrictor muscle at the back
• fuse in the midline at the raphe

Question 13

Where do muscle fibres that make up the inferior constrictor muscle originate from?

Answer 13

From the sides of the thyroid cartilage and the cricoid cartilage.

Question 14

What is the path of the muscle fibres of the inferior constrictor muscle?

Answer 14

• fibres sweep backwards and run outside the lowermost fibres of the middle constrictor
• reach the midline raphe posteriorly

Question 15

What is the lowest part of the pharynx called?

Answer 15

This is called the laryngopharynx.

Question 16

Where does the laryngopharynx lie?

Answer 16

It lies at the level of the larynx.

Question 17

How far does the midline raphe of the pharynx at the back of pharynx extend?

Answer 17

It extends as a continuous seam from the the base of the skull at the top to the beginning of the oesophagus below.

Question 18

How are the 3 constrictor muscles arranged?

Answer 18

They overlap each other like 3 stacked flowerpots.

Question 19

Below the inferior constrictor muscle what is the oesophagus continuous with?

Answer 19

It is continuous with the pharynx.

Question 20

Where is the prevertebral fascia?

Answer 20

This is behind the pharynx and the upper part of the oesophagus.

Question 21

What does the prevertebral fascia cover?

Answer 21

It covers the prevertebral muscle mass.

Question 22

Describe the prevertebral fascia.

Answer 22

This is a well defined layer that allows the free movement of the pharynx and the oesophagus independently of the prevertebral muscle movement.

Question 23

Where is the retropharyngeal space?

Answer 23

This is a potential space between the prevertebral fascia and the posterior wall of the pharynx which is filled with loose connective tissue.

Question 24

What happens when there is infection in the retropharyngeal space?

Answer 24

Infection in this space can spread rapidly and pus that forms here can give rise to a retropharyngeal abscess.

Question 25

What is the framework of the larynx and trachea?

Answer 25

Cartilaginous

Question 26

What is the framework of the pharynx and oesophagus like?

Answer 26

The framework is muscular.

Question 27

What do the different frameworks between the larynx/trachea and pharynx/ oesophagus reflect?

Answer 27

It reflects the different functional requirements of these 2 midline tubes.

Question 28

What are the gaps between the larynx and the hyoid bone closed by?

Answer 28

They are closed by membranes and muscles.

Question 29

What are the gaps between the pharyngeal muscles closed by?

Answer 29

These gaps at the sides at filled with loose connective tissue and several important structures pass through each gap/ space.

Question 30

What covers the inner surfaces of the muscles of the pharynx?

Answer 30

The pharyngobasilar fascia.

Question 31

What is the pharyngobasilar fascia like?

Answer 31

Thin.

Question 32

Why does the pharyngobasilar fascia not exist as a membrane in the lower part of the pharynx?

Answer 32

It would be unable to expand and contract easily.

Question 33

What is the outer surface of the pharynx and cheek covered with?

Answer 33

It is covered with a thin layer of epimysium called the buccopharyngeal membrane.

Question 34

What is the significance of the buccopharyngeal membrane?

Answer 34

This is an insignificant structure beyond facilitating easy movement of the pharynx on the prevertebral fascia

Question 35

What is the gap between the upper border of the superior constrictor muscle and the cranial base covered over with?

Answer 35

With true membranous pharyngobasilar fascia which extends up from the inside of the pharynx between the free superior edge of the constrictor muscle and the base of the skull.

Question 36

Where do the tensor palati and levator palati arise from?

Answer 36

These 2 muscles arise from the base of the skull close tot the superior constrictor muscle and they proceed to the palate.

Question 37

What is the path of the tensor palati?

Answer 37

• runs down the outside of the superior constrictor muscle
• converges to a delicate tendon
• tendon loops around the pterygoid hamulus
  
  • does this to change direction and pass horizontally into the palate

Question 38

What is the path of the levator palati?

Answer 38

• runs over the top of the superior constrictor muscle
• runs through the pharyngobasilar fascia
• reaches the top of the palate from the inside of the nasopharynx

Question 39

What are the other gaps between the upper and middle constrictor muscles of the pharynx and between the middle and inferior constrictor muscles of the pharynx filled with?

Answer 39

They are filled with loose connective tissue but they also allow important muscles and nerves access to the oropharynx and mouth and the laryngopharynx and the larynx.

Question 40

How many muscles arise form the styloid process?

Answer 40

3 muscles q

Question 41

Where do the 3 muscles that arise from the styloid process pass to?

Answer 41

They pass to the tongue, hyoid bone and pharynx.

Question 42

What are the 3 muscles that arise from the styloid process called?

Answer 42

• styloglossus
• stylohyoid
• stylopharyngeus

Question 43

What muscles does the styloglossus pass between to get to the tongue?

Answer 43

Between the superior and middle constrictor muscles.

Question 44

What is the function of the styloglossus?

Answer 44

It acts to pull the tongue upwards and backwards.

Question 45

How does the stylohyoid pass to its insertion in the hyoid bone?

Answer 45

It emerges more superficially and inserts into the hyoid bone at the junction between the body and the greater horn of the hyoid bone.

Question 46

What is the function of the stylohyoid muscle?

Answer 46

It retracts the hyoid bone in the neck.

Question 47

What type of muscle is the stylopharyngeus muscle?

Answer 47

It is the longitudinal muscle of the pharynx.

Question 48

Describe the path of the stylopharyngeus muscle to its insertion.

Answer 48

• passes deep to other styloid muscles as it runs from the styloid process
• passes between the internal and external carotids
• enters the wall of the pharynx by passing over the upper border of the middle constrictor muscle
• once inside, it inserts into the internal surface of the thyroid cartilage.

Question 49

What is stylopharyngeus muscle a guide to?

Answer 49

It is a guide to the position of the glossopharyngeal nerve (9th cranial nerve.

Question 50

What does the stylohyoid muscle form at its insertion?

Answer 50

It forms an arch through which a tendon belonging to the digastric muscle in the superficial layers in the neck can glide.

Question 51

What is the styloglossus muscle involved with?

Answer 51

Delicate and precise movements of the tongue especially during swallowing and speech.