Neck triangles

Question 1

What are the posterior and anterior triangles split by?

Answer 1

Sternocleidomastoid

Question 2

What are the borders of the posterior triangle?

Answer 2

The anterior margin of the trapezius muscle and posterior Margin of the sternocleidomastoid and top of clavicle

Question 3

What is contained in the posterior triangle?

Answer 3

• occipital artery
• spinal accessory nerve (CN XI)
• cervical plexus
• External jugular vein

Question 4

What route does the spinal accessory nerve (CNXI) take?

Answer 4

• originates from spinal cord
• up into posterior cranial fossa
• back into jugular foramen
• across posterior triangle

Question 5

What 3 muscles make up the floor of the posterior triangle?

Answer 5

• splenius captius ( superior aspect)
• levator scapulae
• posterior,middle and anterior scalenes

Question 6

What are the 4 anterior triangles?

Answer 6

• submandibular triangle
• submental triangle
• muscular triangle
• carotid triangle

Question 7

What are the borders of the anterior triangles?

Answer 7

• inferior border of mandible

- anterior border of left and right sternocleidomastoid

Question 8

What does the hyoid bone split?

Answer 8

Supra and infra hyoid areas

Question 9

What muscle forms the floor of the mouth?

Answer 9

mylohyoid

Question 10

Where is the submental triangle found and what are its borders?

Answer 10

• found below the chin

- the borders are anterior belly of digastric and the mylohyoid

Question 11

What does the submental triangle contain?

Answer 11

• anterior jugular vein

- submental lymph nodes (drain lymph from tongue tip, lower lip and lower incisors)

Question 12

What are the boundaries of the submandibular triangles?

Answer 12

• digastric muscle

- inferior border of the mandible

Question 13

What does the submandibular triangles contain?

Answer 13

• submandibular gland
• facial artery and vein
• submandibular lymph nodes
• hypoglossal nerve (CNXII)

Question 14

What route does the hypoglossal nerve (CNXII) take?

Answer 14

-Exits skull via the hypoglossal canal
-descends in the neck
takes 90 degrees turn anteriorly looping around the occipital artery and enters submandibular triangle

Question 15

What does the hypoglossal nerve supply?

Answer 15

Motor supply to striated muscles of tongue (except palatoglossus )

Question 16

What are the borders of carotid triangles?

Answer 16

• posterior belly of digastric
• anterior body of Sternocleidomastoid
• superior belly of omohyoid

Question 17

What does the carotid sheath contain?

Answer 17

• internal jugular vein
• common carotid artery then internal carotid artery
• vagus nerve
• deep cervical lymph nodes

Question 18

Where are the internal jugular vein , vagus nerve and common carotid in relation to each other?

Answer 18

• most lateral- internal jugular vein
• most medial- common carotid artery
• vagus nerve lies between

Question 19

What is the ansa cervicalis made up of and what does it supply?

Answer 19

-C1,2,3 motor fibres and supply strap muscles

Question 20

What does the muscular triangles contain?

Answer 20

strap muscles:

• sternohyoid
• sternthyroid
• thyrohyoid
• Omohyoid

Question 21

What are all 4 strap muscles enervated by and whats the exception?

Answer 21

ansa cervicalis fibres except throhyoid (C1)