Posterior Triangle Of Neck

Question 0

What landmark divides the neck into two triangles?

Answer 0

SCM

Question 1

What innervates the sternocleidomastoid (scm)

Answer 1

Central nerve XI (spinal accessory)

Question 2

What is the action of the SCM?

Answer 2

Unilaterally its contraction tilts the head toward the shoulder of the same side, rotating the face.

Bilaterally they protract the head

Question 3

Where does the SCM attach?

Answer 3

Superiorly to the mastoid process and sternum and to the clavicle inferiorly.

Question 4

Inferior belly of the omohyoid divides the posterior triangle into:

Answer 4

Superior occipital triangle

Lower supraclavicular triangle

Question 5

Brachial plexus is located…

Answer 5

Between the scalenus anterior and medius.

Enters the axilla via the cervicoaxillary canal

Question 6

Brachial plexus innervates

Answer 6

The upper limb. Both sensory and motor

Question 7

Central nerve XI (spinal accessory) innervates

Answer 7

Motor innervation to the SCM and trapezius.

Found anterior to levator scapula

Question 8

Which muscles form floor of the triangle?

Answer 8

Semispinalis capitis 
Splenius capitis 
Levator scapulae 
Scalenus medius 
Scalenus anterior (phrenic nerve crosses anteriorly)

Question 10

Origin of scalene muscles

Answer 10

Arise from the transverse processes of the cervical vertebrae

Question 11

Attachments of the SCM

Answer 11

sternal head- manubrium of sternum

clavicular head- medial third of clavicle

Question 12

Attachments of inferior belly of omohyoid

Answer 12

Superior border of the scapula and attaches on the hyoid bone

Question 13

Innervation of belly of omohyoid

Answer 13

Branch of cervical plexus

Question 14

Function of omohyoid

Answer 14

Depress hyoid and draw larynx and hyoid bone down for phonation and swallowing

Question 15

Attachments of anterior scalene

Answer 15

Scalene tubercle of first rib and transverse processes of the cervical vertebrae.

Question 16

Attachments of middle scalene

Answer 16

First rib and transverse processes of cervical vertebra

Question 17

Attachments of posterior scalene

Answer 17

Outer surface of second rib and transverse processes of cervical vertebra.

Question 18

Action of the scalene muscles (anterior, middle, and inferior)

Answer 18

Elevate ribs, unilaterally act to bend cervical spine and bilaterally act to flex neck

Question 19

Innervation of scalenes

Answer 19

Direct branches from brachial and cervical plexus

Question 20

Attachments of the splenius capitis

Answer 20

ligamentum nuchae and spinous processes of cervical and thoracic vertebra, later superior nuchal line of occipital bone and mastoid process of temporal bone

Question 21

Splenius capitis innervated by

Answer 21

spinal nerves C1-C6

Question 22

Action of splenius capitis

Answer 22

Head and neck extension (bilaterally)

Question 23

What is the base boundary of the posterior triangle?

Answer 23

Superior border of the clavicle

Question 24

What is the anterior border of the posterior triangle?

Answer 24

Posterior border of the SCM

Question 25

What is the posterior border of the posterior triangle?

Answer 25

Anterior border of the trapezius

Question 26

What is the roof of the posterior triangle?

Answer 26

Investing layer of deep cervical fascia

Question 27

What is the floor of the posterior triangle?

Answer 27

Musculature and prevertebral fascia

Question 28

4 Layers of deep cervical fascia in the neck

The investing layer does what?

Answer 28

Surrounds the entire neck. It roofs the posterior and anterior triangles

Question 29

4 Layers of deep cervical fascia in the neck

The pretracheal layer does what?

Answer 29

Forms a sheath around the thyroid gland

Question 30

4 Layers of deep cervical fascia in the neck

The prevertebral layer does what?

Answer 30

Surrounds the vertebra and musculature. It forms the fascial carpet over the floor of the posterior triangle

Question 31

4 Layers of deep cervical fascia in the neck

The Carotid sheath is what?

Answer 31

A condensation of all three layers that form a sheath enclosing the vertical neurovascular bundle of the neck