Brachial Plexus

Question 1

What do the anterior rami of spinal nerves C5-T1 form?

Answer 1

the Brachial Plexus

Question 2

Describe how the brachial plexus weaves in and out of the clavicle and 1st rib

Answer 2

It is posterior to the clavicle, but anterior to the first rib

Question 3

How many roots are there in the brachial plexus?

Answer 3

5 (C5-T1)

Question 4

Where do these roots pass through?

Answer 4

The gap between the anterior and middle scalene muscles along with the subclavian artery

Question 5

In the inferior part of the neck the 5 roots unite to form what?

Answer 5

3 trunks

Question 6

What are the names of the 3 roots and how did they form?

Answer 6

Superior Trunk formed from the union of C5 and C6
Middle Trunk is just a continuation of C7
Inferior Trunk formed from the union of C8 and T1

Question 7

What happens to the three roots as they pass posterior to the clavicle?

Answer 7

They divide into anterior and posterior DIVISIONS

Question 8

These divisions form what?

Answer 8

3 CORDS

Lateral, Medial, and Posterior

Question 9

The lateral cord forms as a result of what?

Answer 9

The union of the anterior division of superior and middle trunks

Question 10

The medial cord forms as a result of what?

Answer 10

It is just a continuation of the anterior division of the inferior trunk

Question 11

The posterior cord forms as a result of what?

Answer 11

The union of the posterior divisions of all 3 trunks

Question 12

Each cord gives rise to what?

Answer 12

Branches or Nerves

Question 13

How many branches arise from the lateral cord?

What are they called?

Answer 13

3

1) Lateral Pectoral Nerve
2) Musculocutaneous Nerve
3) Median Nerve (partly)

Question 14

How many branches arise from the medial cord?

What are they called?

Answer 14

5

1) Median Pectoral Nerve
2) Medial Brachial Cutaneous Nerve
3) Medial Antebrachial Cutaneous Nerve
4) Median Nerve (partly)
5) Ulnar Nerve

Question 15

How many branches arise from the posterior cord?

What are they called?

Answer 15

5

1) Upper Subscapular Nerve
2) Lower Subscapular Nerve
3) Thoracodorsal Nerve
4) Axillary Nerve
5) Radial Nerve

Question 16

There are 2 branches/nerves that arise from the roots, what are they?

Answer 16

1) Dorsal Scapular Nerve

2) Long Thoracic Nerve

Question 17

There are 2 branches/nerves that arise from the trunks, what are they?

Answer 17

1) Nerve to Subclavius

2) Suprascapular Nerve

Question 18

The Long thoracic nerve has origins from where?

Answer 18

C5-7

Question 19

What does the long thoracic nerve innervate?

Answer 19

Serratus Anterior

Question 20

The dorsal scapular nerve has origins from where?

Answer 20

C5

Question 21

What does the dorsal scapular nerve innervate?

Answer 21

Rhomboids

Levator Scapulae

Question 22

The subclavian nerve has origins from where?

Answer 22

C5 and C6

Question 23

What does the subclavian nerve innervate?

Answer 23

Subclavius

Question 24

The suprascapular nerve has origins from where?

Answer 24

C5 and C6

Question 25

What does the suprascapular nerve innervate?

Answer 25

Supraspinatous | Infraspinatous

Question 26

The lateral pectoral nerve has origins from where?

Answer 26

C5 and C6

Question 27

What does the lateral pectoral nerve innervate?

Answer 27

Pectoralis Major

Question 28

The upper subscapular nerve has origins from where?

Answer 28

C5 and C6

Question 29

What does the upper subscapular nerve innervate?

Answer 29

Superior Portion of Subscapularis

Question 30

The thoracodorsal nerve has origins from where?

Answer 30

C6-8

Question 31

What does the thoracodorsal nerve innervate?

Answer 31

Latissimus Dorsi

Question 32

The lower subscapular nerve has origins from where?

Answer 32

C5-6

Question 33

What does the lower subscapular nerve innervate?

Answer 33

Inferior Portion of Subscapularis | Teres Major

Question 34

The medial pectoral nerve has origins from where?

Answer 34

C8 and T1

Question 35

What does the medial pectoral nerve innervate?

Answer 35

Pectoralis Major and Minor

Question 36

The medial brachial cutaneous nerve has origins from where?

Answer 36

T1

Question 37

What does the medial brachial cutaneous nerve innervate?

Answer 37

Skin of medial side of arm

Question 38

The medial antebrachial cutaneous nerve has origins from where?

Answer 38

C8 and T1

Question 39

What does the medial antebrachial cutaneous nerve innervate?

Answer 39

Skin of medial side of forearm

Question 40

The musculocutaneous nerve has origins from where?

Answer 40

C5-7

Question 41

What does the musculocutaneous nerve innervate?

Answer 41

Corocobrachialis Brachialis Biceps Brachii

Question 42

The axillary nerve has origins from where?

Answer 42

C5 and C6

Question 43

What does the axillary nerve innervate?

Answer 43

Deltoid | Teres Minor

Question 44

The radial nerve has origins from where?

Answer 44

C5-T1

Question 45

What does the radial nerve innervate?

Answer 45

``` Triceps Brachii Anconeus Bracioradialis Supinator Extensors of the Forearm ```

Question 46

The median nerve has origins from where?

Answer 46

C5-T1

Question 47

What does the median nerve innervate?

Answer 47

``` Pronator Teres Flexor Carpi Radialis Palmaris Longus Flexor Digitorum Superficialis Flexor Digitorum Profundus (lateral half) Flexor Pollicus Longus Pronator Quadratus Lumbricals 1 & 2 Opponens Pollicis Abductor Pollicis Brevis Flexor Pollicis Brevis ```

Question 48

The ulnar nerve has origins from where?

Answer 48

C7-T1

Question 49

What does the ulnar nerve innervate?

Answer 49

Flexor Carpi Ulnaris Flexor Digitorum Profundus (ulnar half) Intrinsic Hand Muscles