Posterior triangle

Question 1

Name the neck fascia layers and describe what fascia is

Answer 1

Superficial fascia

Investing fascia

prevertebrae fascia

pretracheal fascia

carotid sheath

fascia is

Question 2

What is the superficial fascia

Answer 2

Fatty outer connective tissue containing:

blood vessels, cutaneous muscles, lymphatics and aneriorly, the platysma muscle.

Question 3

What is the investing fascia and its attachments

Answer 3

Surrounds the whole neck minus the superficial layer

surrounds the SCM and trapezius in the neck ‘invests’ them

also fully encloses the submandibular and parotid glands

attaches superiorly to the inferior border of the mandible, the mastoid process, the superior nuchal line, the zygomatic arch.

Attaches inferiorly to the acromion, scapula, manubirum and continuous with thoracic fascia

Question 4

What is the prevertebral fascia

Answer 4

Surrounds the vertebral column and pre+post vertebral muscles.

attaches superiorly to the cranial base and inferiorly it is continuous with the thoracic fascia.

Question 5

What is the pretracheal fascia

Answer 5

Visceral part: Surrounds the trachea, oesophagus and the thyroid gland

Muscular component encloses the infrahyoid muscles

Question 6

What is the carotid sheath?

Answer 6

Fascia that surrounds major vasculature

• the common and internal carotid artery
• internal jugular vein
• also the vagus nerve

Connects the cranial cavity with the thorax via the carotid canal

Question 7

Name the boundaries of the posterior triangle and the roof + floor

Answer 7

Anterior border = Posterior border of the sternocleidomastoid

posterior border = anterior border of the trapezius

inferior border = middle 1/3 of the clavicle

superior border = superior nuchal line

floor = prevertebral fascia

roof = investing fascia

Question 8

Describe the vascular and neurological contents of the posterior triangle

Answer 8

Sub clavicle artery, Occipital artery and transverse cervical artery

subclavical vain, external jugular vein and transverse cervical vein

phrenic nerve

Trunks of the brachial plexus

Spinal accessory nerve

Lesser occipital nerve

greater auricular nerve

Transverse cervical nerve

dosal scapular nerve

Question 9

Describe the muscular contents of the posterior triangle

Answer 9

Sternocleidomastoid and trapezius

semispinalis captis

Splenius captis

levator scapulae

scalenus medius

Scalenus anterior

inferior belly of omohyoid

Question 10

Describe the attachments, innervation and actions of the sternocleidomastoid

Answer 10

Insertion = lateral surface of: mastoid process and superior nuchal line

Origin = eternal head of manubrium and medial 1/3 of clavicle

Innervation = spinal accessory nerve CNXI

Actions = draws the head forward and tilts head toward ipsilateral shoulder while turning the face contralaterally

Question 11

Describe the attachments, innervation and actions of the trapezius

Answer 11

Insertion = lateral 1/3 clavicle, acromion and spine of scapula

Origin = spinous processes c7-t12, ligamentum nuchae, superior nuchal line, occipital protuberance

Innervation = CNXI spinal accessory nerve

Actions = rotation of scapula during adduction of humerus, shoulder elevation and depression, posture

Question 12

Describe the attachments, innervation and actions of the scalenus anterior

Answer 12

Insertion = scalene tubercle of first rib

Origin = transverse process of c3-c6

Innervation = the anterior rami of the spinal nerves C4-C6

Actions = first rib elevation

Question 13

Describe the attachments, innervation and actions of the scalenus medius

Answer 13

Insertion = superior surface of the first rib

origin = transverse process of axis and c3-7

innervation = anterior rami of cervical spinal nerves C3-C8

actions = elevation of first rib

Question 14

Describe the attachments, innervation and actions of the levator scapulae

Answer 14

Insertion = angle of scapula

origin = transverse process of atlas and axis, posterior tubercle of c3-4

innervation = the anterior rami of spinal nerves C3 and C4 and the dorsal scapular nerve (C5)

actions = elevate scapula

Question 15

Describe the cervical plexus,

which branches are muscular and which are cutaneous?

what nerves are in the cervical plexus?

Answer 15

Cervical plexus are nerves leaving the anterior rami of C1-C5

Muscular nerves are: phrenic nerve, Ansa cervicalis and branches to the vertebral and prevertebral muscles

cutaneous nerves are: greater auricular nerve, transverse cervical nerve, supraclavicular nerve, lesser occipital nerve

Question 16

Describe where the external and anterior jugular vein can be found in the posterior triangle

Answer 16

External jugular vein drains into the subclavican vein deep to the middle clavicle

anterior jugular vein drains into the external jugular vein superficial to the sternocleidomastoid