Muscles: Neck (Dustin)

Question 1

Answer 1

Sternocleidomastoid

superficial neck muscle
1. Arises:
o Sternal head:
• Manubrium of the sternum
o Clavicular head:
• Medial third of the clavicle
2. Inserted:
o Mastoid process and superior nuchal line
3. Movement:
o Individually:
Marius
• Tilts head to the same side
• Rotates head to the opposite side
o Together:
• Ventral flexion of the head
4. Innervation:
o Accessory nerve (cranial nerve XI)

Question 2

what is this muscle group and what is the function of their movement?

Answer 2

Infrahyoid muscles

Move thyroid cartilage and hyoid bone together
Pull hyoid bone and the laryngeal cartilages downward
Together with the suprahyoid muscles they bend the head forward with mouth
closed
The omohyoid muscle prevents pressure on the large underlying vein and
assists in opening the mouth and in flexion, lateral flexion and rotation of the
head

Question 3

Answer 3

Sternohyoid
1. Arises:
o Posterior surface of the manubrium
o Sternal end of clavicle
2. Inserted:
o Inner surface of hyoid bone
3. Innervation:
o Cervical ansa of the cervical plexus

Question 4

Answer 4

Omohyoid
Inferior belly
1. Arises:
o Superior margin of scapula, adjacent to the
scapular notch
2. Inserted:
o Intermediate tendon
3. Innervation:
o Cervical ansa of the cervical plexus
Superior belly:
1. Arises:
o Intermediate tendon
2. Inserted:
o Body of the hyoid bone
3. Innervation:
o Cervical ansa of the cervical plexus

Question 5

Answer 5

Sternothyroid
1. Arises:
o Posterior surface of manubrium
2. Inserted:
o Thyroid cartilage
3. Innervation:
o Cervical ansa of the cervical plexus

Question 6

Answer 6

Thyrohyoid
Is a continuation of the sternothyroid.
1. Arises:
o Thyroid cartilage
Marius
2. Inserted:
o Body of the hyoid bone
3. Innervation:
o Ventral ramus of C1

Question 7

what is this muscle group?

Answer 7

suprahyoid muscles:

stylohyoid

mylohyoid

geniohyoid

anterior and posterior bellies of digastric

Question 8

Answer 8

Stylohyoid
1. Arises:
o Styloid process of the temporal bone
2. Inserted:
o Body of the hyoid bone by a split tendon (split by the
digastric muscle)
3. Movement:
o Elevated the hyoid bone (during swallowing)
o Assist in opening the mandible
4. Innervation:
o Facial nerve

Question 9

Answer 9

Mylohyoid
1. Arises:
o Mylohyoid line of the mandible
2. Inserted:
o Body of the hyoid bone by a median tendon of
insertion (mylohyoid raphe)
3. Movement:
o Tightens and elevates the oral floor
o Draws the hyoid bone forward (during
swallowing)
o Assist in opening the mandible and moving it
from side to side
4. Innervation:
o Mylohyoid nerve (from the mandibular nerve)

Question 10

Answer 10

Geniohyoid
1. Arises:
o Mental spine
2. Inserted:
o Body of the hyoid bone
3. Movement:
o Draws the hyoid bone forward (during
swallowing)
o Assist in opening the mandible
4. Innervation:
o Ventral ramus of C1

Question 11

Answer 11

Anterior and Posterior Bellies of Digastric Muscle
Posterior belly
1. Arises:
o Mastoid notch (medial to the mastoid process)
2. Inserted:
o Intermediate tendon, into the hyoid bone
3. Movement:
o Elevates the hyoid bone (during swallowing)
o Assist in opening the mandible
4. Innervation:
o Facial nerve
Anterior belly
1. Arises:
o Digastric fossa of the mandible
2. Inserted:
o Intermediate tendon, into the hyoid bone
3. Movement:
o Elevates the hyoid bone (during swallowing)
o Assist in opening the mandible
4. Innervation:
o Mylohyoid nerve (from the mandibular nerve)

Question 12

(broad muscular area)

Answer 12

Platysma
The platysma is a broad, flat, subcutaneous muscular sheet.
1. Arises:
o Below the clavicle, from the pectoral fascia
2. Inserted:
o Medial fibers:
• Into the mandible
o Lateral fibers:
• Joins the muscles around the mouth
3. Movement:
o Tenses the skin
o Can move the lower lip and the corners of the mouth down
4. Innervation:
o Facial nerve

Question 13

triangles of the neck: A

Answer 13

mandible

Question 14

triangles of the neck: B

Answer 14

hyoid bone

Question 15

triangles of the neck: C

Answer 15

clavicle

Question 16

triangles of the neck: D

Answer 16

trapezius muscle

Question 17

triangles of the neck: E

Answer 17

sternocleidomastoid

Question 18

triangles of the neck: F

Answer 18

omohyoid muscle

runs deeper than sternocleidomastoid

Question 19

triangles of the neck: G

Answer 19

posterior belly of digastric

Question 20

triangles of the neck: H

Answer 20

anterior belly of digastric

Question 21

triangles of the neck: 1

Answer 21

anterior triangle

Question 22

triangles of the neck: 2

Answer 22

posterior triangle

contains Erb’s Point aka punctum nervosum, where 6 nerves meet. Injury to this area results in paralysis of arm muscles

Question 23

triangles of the neck: 3

Answer 23

muscular triangle

aka inferior carotid triangle

• infrahyoid muscles
• thyroid gland

Question 24

triangles of the neck: 4

Answer 24

submental triangle

• submental lymph nodes
• small veins

Question 25

triangles of the neck: 5

Answer 25

**_occipital triangle_** aka omotrapezoid triangle - external jugular vein - brachial plexus - cervical plexus - spinal accessory nerve

Question 26

triangles of neck: 6

Answer 26

**_supraclavicular triangle_** aka subclavian triangle or omoclavicular triangle - subclavian artery and vein - suprascapular artery - usually some lymph glands

Question 27

triangles of neck: 7

Answer 27

**_submandibular triangle_** aka digastric triangle - facial artery and vein - submandibular glands - lymph nodes - mylohyoid nerve

Question 28

triangles of neck: 8

Answer 28

**_carotid triangle_** contains _carotid sheath_: internal jugular vein, common carotid artery, vagus nerve - hypoglossal n - ansa cervicalis - accessory nerve

Question 29

which fascia is in red?

Answer 29

**_superficial lamina of (or investing layer of) deep cervical fascia_** surrounds the neck like a collar, it splits around the sternocleidomastoid muscles and the trapezius muscles. Posteriorly (towards the back of the neck), it blends with ligamentum nuchae. (1 out of 3 deep cervical layers)

Question 30

which fascia is in blue? which is in purple? what do they make together?

Answer 30

**_blue = visceral pretracheal cervical fascia_** - extends medially in front of the carotid vessels, and assists in forming the carotid sheath - fixed to the hyoid bone - encloses the thyroid **_purple = muscular pretracheal cervical fascia_** together they make up the **_middle cervical fascia**_ part of the _**deep cervical fascia_**

Question 31

what is the fascia in orange?

Answer 31

**_prevertebral deep cervical fascia_** -the "deep lamina" of the deep cervical fascia Forms a tubular sheath for the vertebral column and muscles associated with it (longus capitis, longus colli anteriorly) (scalene laterally) (deep cervical muscles posteriorly) Superiorly it's fixed to the cranial base Inferiorly it blends with the endothoracic fascia peripherally, and the anterior longitudinal ligament centrally at Th-3 vertebra level Laterally it extends as the axillary sheath, enclosing the axillary vessels & brachial plexus

Question 32

what is the structure in brown?

Answer 32

**_carotid sheath_** borders blend with _prevertebral cervical fascia_ and _pretracheal cervical fascia_ contains: * common carotid artery* * internal jugular vein* * vagus nerve*

Question 33

what is the layer _external_ to the _red_ line?

Answer 33

**superficial cervical fascia** - *not to be confused with superficial lamina of deep cervical fascia!* - lies between the dermis of the skin and the deep cervical fascia. - contains the platysma, cutaneous nerves, blood, and lymphatic vessels. - also contains a varying amount of fat, which is its distinguishing characteristic. - technically not really even fascia