10/8 Brachial Plexus - Carter 2017 (Completed)

Question 1

What does the brachial plexus originate from? How many trunks are there?

Answer 1

Ventral primary rami (C5 - T1)

These five roots become three trunks

Question 2

What forms the upper trunk of the brachial plexus?

Answer 2

The union of C5 and C6

Question 3

What forms the middle trunk of the brachial plexus?

Answer 3

The continuation of the C7 ventral rami root

Question 4

What forms the lower trunk of the brachial plexus?

Answer 4

The union of ventral rami roots C8 and T1

Question 5

How many division are there of the brachial plexus?

Answer 5

There is an anterior and posterior division for each trunk, therefore, there are 6 divisions of the brachial plexus

Question 6

After 3 trunks are given away from the five rootlets (C5 - T1) these trunks divide into anterior and posterior divisions (6). What do they form next?

Answer 6

Anterior divisions of the upper and medial trunk form the lateral cord (C5 - C7)

Anterior division of the lower trunk continues to become the medial cord (C8 - T1)

The posterior divisions of all three trunks form the posterior cord (C5 - T1)

Question 7

After the rootlets of the ventral rami form trunks and those trunks form divisions and those divisions give way to cords what are we left with?

Answer 7

Terminal divisions

Question 8

What are the divisions of the lateral cord?

Answer 8

Lateral pectoral n. (C5 - C7)

Musculocutaneous n. (C5 - C7) (terminal)

Lateral root of median n.

Question 9

What are the divisions of the medial cord?

Answer 9

Medial pectoral n. (C8 - T1)

Medial brachial cutaneous n. (C8 - T1)

Medial antebrachial cutaneous n. (C8 -T1)

Ulnar n. (C8 - T1) (terminal)

Medial root of median n.

Question 10

What are the divisions of the posterior cord?

Answer 10

Thoracodorsal n. (C6 - C8)

Axillary n. (C5 - C6) (terminal)

Upper subscapular n. (C5 - C6)

Lower subscapular n. (C5 - C6)

Radial n. (C5 - T1) (terminal)

Question 11

What does the lateral root of the median n. From the lateral cord and the medial root of the median n. From the medial cord form?

Answer 11

Forms the median n. Terminal branch

Question 12

What is Erb-Duchenne Paralysis (Erb’s Palsy)?

Answer 12

Effects the upper trunk (C5 - C6) affecting the shoulder and arm

Question 13

In Erb’s Palsy what muscles are effected?

Answer 13

Deltoid m.

Supraspinatus m.

Infraspinatus m.

Subscapularis m.

Question 14

What’s Klumpke’s Paralysis (Klumpke-Dejerine)?

Answer 14

Effects the lower trunk (C8 - T1) affecting the forearm and hand

Question 15

What occurs as a result of Klumpke’s paralysis?

Answer 15

Paralysis of the muscles and skin innervated by the ulnar n.

If it occurs at birth the upper extremity does not grow t the proper length

Question 16

What is Cervical Rib Syndrome (Thoracic Outlet Syndrome)?

Answer 16

Chronic injury to brachial plexus in lower part of neck and often subclavian a.

Question 17

What occurs as a result of Cervical Rib Syndrome (Thoracic Outlet Syndrome)

Answer 17

Lower trunk injury by the apex of the axilla