Neck Anatomy & Posterior Triangles

Question 1

What muscle serves as the division between the anterior and posterior cervical triangles

Answer 1

Sternocleidomastoid

• –Anterior boundary for post. triangle
• –Posterior boundary for ant. triangle

Question 2

Boundaries of the posterior cervical triangle

Answer 2

• Ant. - Posterior border of SCM
• Post. - Anterior border of Trap
• Inferior - middle 1/3 of clavicle
• Apex -insertion of SCM & Trap on Superior nuchal line
• Roof - facia overlying platysma
• Floor -prevertebral fascia overlying Trap, SCM, Platysma

Question 3

Divisions of Posterior Cervical Triangle

Answer 3

Occiptial triangle

Supraclavicular (subclavian) triangle

Question 4

What divides the Occipital Triangle & Supraclavicular (Subclavian) Triangle?

Answer 4

Inferior belly of the omohyoid muscle as it crosses the inferior ends of Middle & Posterior Scalene muscles

Question 5

Contents of the Occipital Triangle

Answer 5

• Occipital Artery near apex (a branch of external carotid artery)
• Spinal Accessory Nerve (CXI) as it crosses between Trap & SCM

Question 6

Contents of Supraclavicular(subclavian) triangle

Answer 6

• Subclavian Artery & Vein

- Root & trunks of Brachial Plexus

Question 7

Where does External Jugular Vein lie

Answer 7

In superficial facisa of roof of post. triangle, until it approaches base, where it goes through deep facia & dumps into subclavian vein deep to SCM

Question 8

What arteries of the Thyrocervical trunk cross the posterior triangle?

Answer 8

Transverse cervical & Suprascapular

Question 9

Besides Spinal Accessory Nerve what other nerves can be found in posterior triangle?

Answer 9

• Ventral Rami of the Brachial Plexus

- Branches of Cervical Plexus of nerves C1-C4

Question 10

Name the Branches of the Cervical Plexus that can be found in the Posterior Triangle?

Answer 10

Lesser Occipital Nerve (C2)
Great Auricular Nerve (C2,C3)
Transverse Cervical Nerve (C2, C3)
Supraclavicular Nerve (C3, C4)
Phrenic Nerve (C3-C5)

Question 11

What does Lesser Occipital Nerve (C2) supply?

Answer 11

Skin of neck and scalp posterior to the ear

Question 12

What does Great Auricular nerve (C2,C3) supply?

Answer 12

Skin of neck and part of ear

Question 13

What does Transverse Cervical Nerve (C2,C3) supply?

Answer 13

Skin over Ant. Triangle of neck

Question 14

What does Supraclavicular Nerve (C3,C4) supply?

Answer 14

Skin of the chest over clavicle, sternoclavicular joint, & Acromioclavicualr jt

Question 15

What does Phrenic Nerve (C3,C5) supply?

Answer 15

Enters Thorax to innervate diaphragm

—identified lying on Anterior Scalene Muscle