Root of the neck - scalenus anterior (dave's notes)

Question 1

What is the origin and attachment of scalenus anterior?

Answer 1

Arises from C3-6 with 4 slender tendons lying end to end with those of longus capitus, ending in a narrow tendon attached to the scalene tubercle and ridge of the inner border of the upper surface of the first rib.

Question 2

What covers scalenus anterior?

Answer 2

A prolongation of the prevertebral fascia

Question 3

What is the nerve supply to scalenus anterior?

Answer 3

Segmental

Question 4

List the anterior relations of scalenus anterior

Answer 4

Phrenic nerve
Ascending cervical artery
Transverse cervical and suprascapular arteries
Vagus nerve
Internal jugular vein
Subclavian vein

Question 5

List the medial relations of scalenus anterior

Answer 5

Edge of longus colli
Subclavian artery 
1st rib
Thoracic duct/Right lymphatic duct
Carotid tubercle
Common carotid artery
Stellate ganglion
Vertebral artery and veins
Inferior thyroid artery
Ansa cervicalis
Connecting loop between middle and inferior cervical ganglia
Vertebral vein

Question 6

List the posterior relations of scalenus anterior

Answer 6

Subclavian artery
Anterior rami of C7/T1
Scalenus medius

Question 7

List the lateral relations of scalenus anterior

Answer 7

Trunks of the brachial plexus

The 3rd part of the subclavian artery

Question 8

Why do the arteries have free entry to the pyramidal space?

Answer 8

There is no prevertebral fascia here

Question 9

Anterior relation of scalenus anterior: describe the course of the phrenic nerve

Answer 9

Passes vertically downwards plastered by the prevertebral fascia, then crosses the subclavian artery. From the supra pleural membrane it passes medially to the apex of the lung anterior to the vagus

Question 10

Anterior relation of scalenus anterior: Describe the course of the ascending cervical artery

Answer 10

From inferior thyroid artery/thyrocervical trunk it runs up medial to the phrenic nerve on the prevertebral fascia

Question 11

Anterior relation of scalenus anterior: what two arteries are found between scalenus anterior and the carotid sheath?

Answer 11

Transverse cervical and suprascapular arteries

Question 12

Anterior relation of scalenus anterior: Describe the course of the vagus nerve

Answer 12

The vagus nerve in the carotid sheath passes down in front of the subclavian artery (giving off the recurrent on the right). The vagus inclines posteriorly running on the medial surface of the apex of the lung

Question 13

What surrounds the internal jugular vein?

Answer 13

The inferior deep cervical lymph nodes

Question 14

Anterior relation of scalenus anterior: Where is the subclavian found relative to scalenus anterior?

Answer 14

The subclavian vein lies in a groove on the first rib, lying lower than the insertion of the scalenus anterior

Question 15

Medial relation of scalenus anterior: What makes a pyramidal space with scalenus anterior?

Answer 15

The medial edge of longus colli running up on the anterior tubercle of C6

Question 16

Medial relation of scalenus anterior: What is found at the base of the pyramidal space?

Answer 16

The subclavian artery and neck of the first rib, the thoracic duct (lymph duct on the right) arches over the lung apex and subclavian artery to enter at the confluence

Question 17

What are the branches of the subclavian artery?

Answer 17

Vertebral
Thyrocervical trunk
Internal thoracic artery

Question 18

What are the branches of the thyrocervical trunk?

Answer 18

Transverse cervical
Suprascapular
Inferior thyroid artery

Question 19

Medial relation of scalenus anterior: What is at the apex of the pyramidal space?

Answer 19

The carotid tubercle

Question 20

Medial relation of scalenus anterior: What lies immediately in front of the pyramidal space?

Answer 20

The common carotid artery

Question 21

Medial relation of scalenus anterior: What arches in front of the apex of the pyramidal space?

Answer 21

The internal thoracic artery.

Question 22

Describe the course of the vertebral vein from C6

Answer 22

The vertebral vein emerges from the foramen in the transverse process of C6, runs over the apex of the lung and beneath the subclavian artery to the brachiocephalic vein

Question 23

Posterior relations of scalenus anterior: Describe the second part of the subclavian artery

Answer 23

The second part of the subclavian artery is the part lying behind scalenus anterior. It gives rise to the costorcervical trunk (which gives of the superior intercostal artery and deep cervical artery)

Question 24

Posterior relations of scalenus anterior: What separates scalenus anterior from scalenus medius?

Answer 24

The subclavian artery and the anterior rami of C7/T1

Question 25

Lateral relations of scalenus anterior: What plasters down the trunks of the brachial plexus?

Answer 25

The prevertebral fascia

Question 26

Posterior relations of scalenus anterior: Describe the third part of the subclavian artery

Answer 26

The third part of the subclavian artery is behind the prevertebral fascia and gives off the dorsal scapular branch