Anterior Triangle of the Neck

Question 1

Anterior Triangle Boundaries

Answer 1

Lateral: Anterior border of SCM
Sup: Inferior border of the mandible
Med: Midline of the neck

Question 2

What are the four strap/ infrahyoid muscles

Innervation? (loner ones are done by?)

Answer 2

Sternohyoid (superficial)
Thyrohyoid and Sternothyroid (Deep)
Omohyoid

Sternohyoid, omohyoid and sternothyroid Inferior root (C2-3)
Thyrohyoid: Superior root/loop of AC, C1

Question 3

Cervical Plexus and Ansa Cervicalis (loops)

Answer 3

C1-C4

Ansa Cervicalis Roots C1-3 (note is motor)
Superior root- C1
Inferior root- C2,3

Question 4

Where does the thyroid isthmnus sit?

Answer 4

On top of the 2/3 tracheal cartilage, also note thyroid cartilage above the thyroid gland

Question 5

Thyroid Arterial supply

Answer 5

Superior thyroid Artery: FIRST BRANCH of the external carotid
Inferior Thyroid artery: Thyrocervical trunk from subclavian

Question 6

Thyroid Venous drainage

Lymphatic drainage

Answer 6

Sup, middle and inferior veins
Sup and middle veins drain to Internal jugular vein
Inf drains to (left) brachiocephalic trunk

Lymphatic: Paratracheal and Deep cervical nodes

Question 7

Where do the recurrent laryngeal nerves run? General relations

Answer 7

In a groove between trachea and oesophagus

In pretracheal fascia, and net to carotid sheath

Question 8

Thyroid embryology

Answer 8

Migrates from foramen caecum (at tongue base) through thyroglossal duct. Can get accessory tyroid, cervical and pyramdial thyroid

Question 9

Suprhyoid Muscles

Innervation

Answer 9

MIDLINE: sup-deep
Anterior belly of digastric; Mylohyoid; Geniohyoid

LATERAL: Post belly of digastric (attaches to mastoid process); stylohyoid (attaches too styloid process)

Innervation: Post belly of digastric and stylohyoid- Facial nerve
Mylohyoid and Ant belly of digastric: V3
Geniohyoid: C1

Question 10

What forms the external jugular vein?

Answer 10

Posterior auricular and retromandibular vein

Question 11

Vagus nerve
Exits the skull through
Travels through
At the root of the neck
Gives off branches

Answer 11

• Jugular foramen
• Carotid sheath
• Stays close to midline, in front of subclavian artery and behind vein

Question 12

Glossopharyngeal Nerve
Exits the skull through
Travels through
At the root of the neck
Gives off branches

Answer 12

• Jugular Foramen
• Deep to post belly of digastric/styloid process, Between external and internal carotid, curves around stylopharyngeus to base of tongue (post 1/3 of tongue sensation)

Question 13

Hypoglossal nerve
Exits the skull through
Travels through
At the root of the neck
Gives off branches

Answer 13

-Hypoglossal canal
- Deep to post belly digastric + stylohyoid; runs between internal jugular and internal carotid (superficail to this) and runs to tongue
A branch of C1 travels with, to innervate geniohyoid and thryohyoid

Question 14

Research paper

Locations of hyoid, thyroid cartilage, cricoid cartilage, CC bifurcation

Answer 14

Hyoid: C3
CCA Bifurcation: C3
Thyroid cartilage: C4 women, C5 men
Cricoid cartilage: C6