Anatomy of Thyroid and Parathyroid glands

Question 1

What do the lobes of the thyroid gland attach onto?

Answer 1

lateral aspects of the thyroid & cricoid cartilages & to the trachea

Question 2

Which level of cartilage does the isthmus lie anterior to?

Answer 2

2nd and 3rd tracheal cartilages

thyroid gland spans from C5 and T1

Question 3

A goitre will move in which directions on swallowing?

Answer 3

superiorly then inferiorly

Question 4

Where are the parathyroid glands located?

Answer 4

on the posterior surfaces of the thyroid gland’s lateral lobes

Question 5

What is a pyramidal lobe?

Answer 5

a variation in structure of the thyroid gland where there is an incomplete isthmus
the result is an extension of the left lateral lobe superiorly to attach to the thyroid cartilage - can extend as far up as the hyoid bone

Question 6

what is the thyroglossal duct?

Answer 6

embryological structure which connects the descending thyroid gland to the tongue

Question 7

What is ectopic thyroid tissue and where is it found?

Answer 7

aka. thyroglossal duct cysts, are cysts which arise from the thyroglossal duct and can be found at any position in the migratory path of the gland from the foramen caecum

Question 8

What are the platysma muscles?

Answer 8

skeletal muscles in the superficial fascia of the neck - belong to the muscles of facial expression

Question 9

What is the nerve supply of the platysma muscles?

Answer 9

CN VII

Question 10

Name the fascial compartments of the neck.

Answer 10

Pre-vertebral (deep) fascia
Investing fascia
Pre-tracheal fascia
2 Carotid sheaths

Question 11

Which fascial compartment contains postural neck muscles & cervical vertebrae?

Answer 11

Pre-vertebral (deep) fascia

located posteriorly

Question 12

Which compartment contains all but one of the facial compartments?

Answer 12

investing fascia - also encloses 2 pairs of muscles - trapezius and sternocleidomastoid

Question 13

What do the carotid sheaths of the neck contain?

Answer 13

vagus nerves
deep cervical lymph nodes
carotid arteries
internal jugular vein

Question 14

What is the contents of pre-tracheal fascia?

Answer 14

oesophagus, trachea, thyroid gland, strap muscles, recurrent laryngeal nerves

Question 15

Which cranial nerve supplies the muscles located in the investing facia compartment?

Answer 15

CN XI (spinal accessory) supplies SCM and trapezius

Question 16

Name the 2 heads of the SCM muscle and where they attach.

Answer 16

Sternal head - manubrium of sternum
Clavicular head - medial end of clavicle

Both heads pass superiorly to attach to mastoid process of temporal bone.

Question 17

What is the blood supply to the thyroid and parathyroid glands?

Answer 17

External carotid artery, 1st branch = superior thyroid artery (anterior/superior aspect)
Right subclavian artery -> inferior thyroid artery (posterior-inferior aspect)
Brachiocephalic artery -> thyroid ima artery (present in 10%); anterior aspect & isthmus

Question 18

What is the venous drainage fo the glands?

Answer 18

superior and middle thyroid veins drain into internal jugular veins, then brachiocephalic.
inferior thyroid vein drains into brachiocephalic -> SVC

Question 19

Where do the left and right recurrent laryngeal nerves recur?

Answer 19

right - under subclavian artery

left - under arch of aorta

Question 20

Name the strap muscles.

Answer 20

Sternohyoid
Sternothyroid
Thyrohyoid
Omohyoid

Question 21

What is the purpose of a fascial sling in relation to the omohyoid?

Answer 21

attaches the intermediate tendon of the omohyoid to the clavicle

Question 22

What are the borders of the anterior triangle of the neck?

Answer 22

inferior border of mandible
midline of neck
sternal head of SCM
Apex at jugular notch (of manubrium)

Question 23

What are the borders of the posterior triangle?

Answer 23

clavicular head of SCM
trapezius muscle
right clavicle

Question 24

Air moves through which opening in the trachea?

Answer 24

rima glottis - opening between vocal cords

Question 25

What is Berry’s ligament?

Answer 25

a suspensory ligament on posterior surface of thyroid gland which attaches it to mostly cricoid cartilage