L30. The Neck Flashcards
Where does the neck run from/to?
Mandible and skull to thoracic inlet (first rib)
How is the neck divided?
Into anterior and posterior regions by the sternocleidomastoid muscle.
Where does the sternocleidomastoid’s proximal attachment lie?
Mastoid process (bony prominence behind the ear)
Where is the distal attachment of the sternocleidomastoid?
The sternum and clavicle
What are the 2 main functions of the sternocleidomastoid muscle?
Tilts the head downwards
Turns head from side to side
Which 2 habits increase the risk of head and neck cancers by 10x?
Smoking and alcohol
Name the 3 regions which make up the anterior triangle of the neck.
Sternocleidomastoid, lower border of the mandible and the midline of the neck (profile).
Name 3 muscles in the anterior portion of the neck.
Mylohyoid - forms a hammock under the mandible
Anterior belly of digastric - 2 strands of muscle running from centre of the mandible down into the neck.
Infrahyoid “strap” muscle - sternohyoid, sternothyroid, thyrohyoid, omohyoid
Name the 4 skeletal elements in the anterior portion of the neck.
Thyroid cartilage
Cricoid cartilage
Hyoid bone
Trachea
Name the 4 glands in the anterior portion of the neck and whether they are endocrine or exocrine.
Thyroid and parathyroid glands - both endocrine. They release hormones into the blood.
Submandibular gland - exocrine so secretions are made via a duct.
Sublingual
Name the connective tissue which encloses the thyroid gland.
Pre-tracheal fascia
Name the arteries which supply the thyroid gland.
Superior thyroid artery (external carotid) and inferior thyroid artery (thyro-cervical trunk)
How could you feel for an enlarged thyroid gland?
A lump when swallowing
Name the small area of thyroid gland which connects the left and right lobes.
Isthmus
Name the third lobe of the thyroid gland, present in 10-30% of the population.
Pyramidal lobe is a projection from the isthmus.
Name the 2 sets [parathyroid] which sit inside the thyroid gland.
Superior set and inferior set
What does parathyroid hormone do?
Increases the uptake of calcium from bone, gut and kidneys.
Why must calcium levels be maintained?
If it is not maintained, muscles (eg heart) cannot contract.
What 2 conditions can arise if the parathyroid glands are removed (eg after a thyroidectomy)?
Tetany (extra muscle contractions)
Atrophy (muscle wastage)
Name the 3 nerves present in the neck’s anterior triangle and the structures each innervates.
Vagus nerve - larynx, trachea, rest and digest
Phrenic nerve - originates in the neck, C3,4,5 keeps the diaphragm alive.
Hypoglossal - tongue motor control
Which nerve used to be divided to help with symptoms of TB?
Phrenic nerve
Between which cervical vertebrae does the common carotid artery bifurcate?
C4 and C5
80% of the brain’s blood supply comes from 1 artery, and 20% from another. What are these?
80% = internal carotid artery 20% = vertebral artery
Name the vessels present in the anterior triange
common carotid artery
jugular veins
Name the 5 jugular veins, and where each runs.
- Anterior - down neck midline
- Retromandibular - brain to in front of spine
- internal jugular - deep, in front of vertebrae
- External jugular - superficial, slightly behind vertebrae
- vertebral vein - deep, runs through vertebrae
Name the 2 nerves in the posterior triangle of the neck.
Accessory nerve (motor, supplies trapezius and sternocleidomastoid) Brachial plexus - from spinal cord to underarm (motor and sensation) from C5,6,7,8 and T1.
What are lymph nodes?
Small structures which drain lymph fluid (eg lymphocytes) to prevent the spread of infection. They drain from superficial to deep.
Give 2 examples of causes of neck swellings.
Enlarged thyroid gland (goitre)
cysts
