Posterior Trisngle Of The Neck

Question 1

Skin of the back of the neck and scalp innervated by

Answer 1

Dorsal rami of spinal nerves C2-C5

Question 2

Skin of anterior and lateral aspects of neck are innervated by

Answer 2

Ventral rami of C2-C4 spinal nerves via cutaneous branches of cervical plexus

Question 3

Where do the ventral rami of C2-C4 spinal nerves emerge from?

Answer 3

Underneath posterior border of sternocleidomastoid muscle

Question 4

What does the ventral rami of C2-C4 spinal nerves via the cutaneous branches of the cervical plexus supply?

Answer 4

Skin of anterior and lateral aspects of the neck

Question 5

What are the cutaneous branches of cervical plexus?

Answer 5

• Lesser occipital nerve (C2 or C2, C3)
• greater auricular nerve (C2, C3)
• transverse cervical nerve (C2, C3)
• supraclavicular nerves (C3, C4)

Question 6

Lesser occipital nerve

Answer 6

• cutaneous branch of cervical plexus
• C2 or C2, C3
• follows posterior border of sternocleidomastoid
• supplies skin over lateral part of accipital region and upper part of medial surface of auricle

Question 7

greater auricular nerve

Answer 7

• cutaneous branch of cervical plexus
• C2, C3
• ascends superficial to sternocleidomastoid, parallel to external jugular vein
• supplies skin over angle of mandible and parotid gland, and both surfaces of lower part of auricle

Question 8

Transverse cervical nerve

Answer 8

• cutaneous branch of cervical plexus
• C2, C3
• runs anteriorly, superficial to sternocleidomastoid
• supplies skin of anterior and lateral aspects of neck

Question 9

Supraclavicular nerves

Answer 9

• cutaneous branch of the cervical plexus
• C3, C4
• arise by a common trunk, which divides into medial, intermediate, and later supraclavicular nerves
• descend across side of lower neck
• supply skin at base of neck and skin that covers upper parts of pectoral is major and deltoid muscles

Question 10

What are the medial branches of dorsal rami of cervical spinal nerves?

Answer 10

• greater occipital nerve (C2)
• 3rd occipital nerve (C3)
• from 4th, 5th, 6th, and 7th nerves in succession below

Question 11

What is the platysma?

Answer 11

The muscle embedded in superficial fascia of neck

Question 12

Origin of platysma

Answer 12

Deep fascia that covers upper parts of pectoralis major and deltoid muscles

Question 13

Insertion of platysma

Answer 13

Fibers pass superficial to clavicle and run superiorly and medically over side of neck, some fibers insert into lower border of body of mandible, other fibers enter face and blend with muscles of lower lip and angle of mouth

Question 14

Nerve supply of platysma

Answer 14

Cervical branch of facial nerve (CN VII)

Question 15

Actions of platysma

Answer 15

• tenses skin of neck
• helps to depress mandible
• draws down lower lip and angle of mouth

Question 16

External jugular vein

Answer 16

• begins posterior to angle of mandible by union of posterior auricular vein and posterior branch of retromandibular vein
• descends obliquely, superficial to sternocleidomastoid, toward middle of clavicle, pierces investing layer of deep cervical fascia, then drains into subclavian vein

Question 17

Posterior auricular vein

Answer 17

Drains scalp posterior and superior to auricle

Question 18

Retromandibular vein

Answer 18

• formed within parotid gland by union of superficial temporal and maxillary veins
• at lower end of gland it divides into anterior and posterior branches (anterior joins facial vein, posterior joins posterior auricular vein to form EJV)

Question 19

Trubutaries of EJV

Answer 19

Transverse cervical
Supra scapular
Anterior jugular veins

Question 20

Where does the anterior jugular vein begin?

Answer 20

In submental region by union of several small veins

Question 21

Where does the anterior jugular vein descend?

Answer 21

Close to anterior midline, just superior to jugular (suprasternal) notch of sternum it turns laterally and passes posterior (deep) to sternocleidomastoid, then drains into external jugular vein

Question 22

What are the right and left anterior jugular veins USUALLY joined by?

Answer 22

Usually joined across midline by jugular venous arch

Question 23

Origin of sternocleidomastoid

Answer 23

Anterior surface of mnubrium of sternum and superior surface of medial third of clavicle (clavicular head)

Question 24

Insertion of sternocleidomastoid

Answer 24

Two heads of origin, muscle passes superiorly, posteriorly, and laterally, then inserts into mastoid process and lateral part of superior nuchal line

Question 25

Nerve supply to the sternocleidomastoid

Answer 25

- Accessory nerve (CN 11) for motor. | - Branches from ventral rami of C2 and C3 spinal nerves (proprioceptive)

Question 26

What divides the anterolateral part of neck into anterior and posterior triangles?

Answer 26

Sternocleidomastoid

Question 27

Sternocleidomastoid actions

Answer 27

- unilateral contraction | - bilateral contraction

Question 28

Unilateral contraction of the sternocleidomastoid

Answer 28

- lateral flexion of head and neck to sam side of contracting muscle - rotation of head and neck to opposite side of contracting muscle

Question 29

Bilateral contraction of sternocleidomastoid

Answer 29

- draw head forward - flexion of head and neck against resistance (doing sit up) - if head is fixed, it can act as an accessory muscle of inspiration

Question 30

What does deep cervical fascia consist of?

Answer 30

Connective tissue that supports muscles, vessels, nerves, and viscera of neck

Question 31

Investing later of the deep cervical fascia

Answer 31

- superficial - completely encircles neck like a collar, splitting to enclose sternocleidomastoid and trapezius - roofs over anterior and posterior triangles

Question 32

Pretracheal layer of deep cervical fascia

Answer 32

- anterior part of neck | - muscular part (encloses infrhyoid muscles) and visceral part (enclose thyroid, larynx, etc)

Question 33

What is the pretracheal layer of the deep cervical fascia known as posterior to pharynx and esophagus?

Answer 33

Buccopharyngeal fascia

Question 34

Prevertebral layer of deep cervical fascia

Answer 34

- located in posterior part of neck | - surrounds cervical vertebrae and anterior and posterior vertebral muscles

Question 35

Carotid sheath of deep cervical fascia

Answer 35

- fascia tube extending from base of skull to root of neck | - contains common and internal carotid arteries, internal jugular vein, and vagus nerve ***

Question 36

What is the retropharyngeal space of the deep cervical fascia?

Answer 36

Interval between buccopharyngeal fascia (anteriorly) and prevertebral fascia (posteriorly), filled with loose connective tissue -closed laterally by carotid sheaths

Question 37

Where does the retropharyngeal space of the deep cervical fascia extend?

Answer 37

Form base of skull to mediastinum

Question 38

Loose connective tissue of the retropharyngeal space of the deep cervical fascia

Answer 38

Accommodates movements of pharynx and esophagus during swallowing

Question 39

What represents a pathway through which neck infections can spread to mediastinum?

Answer 39

The retropharyngeal space of the deep cervical fascia

Question 40

What are all the layers of the deep cervical fascia?

Answer 40

- investing layer - pretracheal layer - prevertebral layer - carotid sheath - retropharyngeal space

Question 41

Anterior boundary of posterior triangle of neck

Answer 41

Posterior border of sternocleidomastoid

Question 42

Posterior border of thee posterior triangle of the neck

Answer 42

Anterior border of the trapezius

Question 43

Inferior border of the posterior triangle of the neck

Answer 43

Middle 1/3 of clavicle

Question 44

What is the posterior triangle of the neck covered by?

Answer 44

- skin - superficial fascia - platysma - investing layer of deep cervical fascia

Question 45

Floor of the posterior trnagle of the neck

Answer 45

-splenius capitis -levator scapulae -scalenus posterior -scalenus medius All covered by the prevertebral layer of the deep cervical fascia small part of scalenus anterior may be present but it is usually hidden by sternocleidomastoid

Question 46

What divides the posterior triangle into occipital triangle and supraclavicular triangle?

Answer 46

Inferior belly of omohyoid

Question 47

Origin of scalenus anterior

Answer 47

Transverse process of C3 and C6 vertebrae

Question 48

Insertion of scalenus anterior

Answer 48

Superior surface of 1st rib and scalene tubercle

Question 49

What muscle holds your neck up?

Answer 49

Scalenus anterior

Question 50

Structures that are anterior to scalenus anterior

Answer 50

-subclavian vein -phrenic nerve -superficial cervical -suprascapular arteries -terminal part of thoracic duct *

Question 51

Structures that are posterior to scalenus anterior

Answer 51

-brachial plexus -subclavian artery *

Question 52

What is the largest and longest of the scalene muscles?

Answer 52

Scalenus medius

Question 53

Origin of scalenus medius

Answer 53

Transverse process of C2 to C7 vertebrae

Question 54

Insertion of scalenus medius

Answer 54

Superior surface of 1st rib, between costal tubercle and groove for subclavian artery

Question 55

What is the smalles of the scalene muscles?

Answer 55

Scalenus posterior

Question 56

Origin of scalenus posterior

Answer 56

Transverse processes of C4 to C6 vertebrae

Question 57

Insertion of scalenus posterior

Answer 57

Outer surface of 2nd rib

Question 58

Nerve supply of scalene muscles

Answer 58

Direct muscular branch from ventral rami of cervical spinal nerves

Question 59

Actions of scalene muscles

Answer 59

- lateral flexion of neck | - accessory muscles of inspiration (elevate 1st and 2nd ribs in forced inspiration)

Question 60

Inferior belly of omohyoid

Answer 60

- Attaches to superior border of scapula, just medial to suprascapular notch - passes anteriorly and superiorly, across lower part of posterior triangle of neck, then passes deep to sternocleidomastoid and ends in intermediate tendon

Question 61

Superior belly of omohyoid

Answer 61

Begins at intermediate tendon, ascends almost vertically in anterior triangle of neck, then attaches to body of hyoid

Question 62

Angulated course of omohyoid

Answer 62

Maintained by loop of deep cervical fascia that surrounds intermediate tendon and attaches inferiorly to clavicle and 1st rib

Question 63

Nerve supply to omohyoid

Answer 63

Ansa cervicalis (ventral rami of C1 to C3)

Question 64

Action of omohyoid

Answer 64

Depresses hyoid bone

Question 65

Arteries of the posterior triangle of the neck

Answer 65

- subclavian artery (3rd part) - superficial (transverse) cervical artery - suprascapular artery - dorsal scapular artery - occipital artery

Question 66

Veins of the posterior triangle of the neck

Answer 66

- external jugular vein and its tributaries | - subclavian vein (occasionally)

Question 67

Nerves of the posterior triangle of the neck

Answer 67

- brachial plexus and branches arising from its roots and trunks - accessory nerve - branches of cervical plexus

Question 68

What other structures are in the posterior triangle of the neck?

Answer 68

- some cervical lymph nodes (along course of accessory nerve and superficial/transverse cervical vessels) - inferior belly of omohyoid muscle