Brachial Plexus

Question 1

Brachial plexus

Answer 1

network of somatic nerves formed by union of cervical ventral rami C5-T1

Question 2

All somatic plexuses are formed by:

Answer 2

ventral rami of spinal nerves

Question 3

responsible for:

Answer 3

innervating most of the upper limb

Question 4

originates:
runs:

Answer 4

in the cervical region
distal - laterally
inferior to the clavicle
enters the axilla

Question 5

5 Major components

Answer 5

Roots (the ventral rami of spinal nerves)
Trunks (superior, middle, inferior)
Divisions (anterior, posterior)
Cords (medial, lateral, posterior)
Terminal Nerves (aka terminal branches)

Question 6

Roots

Answer 6

ventral rami from spinal nerves C5-T1

variable contributions from C4 and T2

Question 7

Roots carry both:

Answer 7

somatomotor and somatosensory fibers

Question 8

Roots emerge from:

Answer 8

in the neck between the anterior scalene and middle scalene muscles

Question 9

Roots give off:

Answer 9

the dorsal scapular nerve (C5)
long thoracic nerve (C5-C7)
phrenic nerve (supplies the diaphragm)

Question 10

Roots unite to form

Answer 10

three trunks
upper, middle, lower trunks
proximal to clavicle

Question 11

Upper trunk formed by:

Answer 11

union of ventral rami C5-C6

Question 12

Lower trunk formed by:

Answer 12

union of ventral rami C8-T1

Question 13

Middle trunk formed by:

Answer 13

ventral ramus of C7

Question 14

Upper trunk only trunk that:

Answer 14

gives rise to nerve branches

Question 15

those nerve branches are

Answer 15

1. Suprascapular nerve (supplies Supra&Infraspinatus)

2. Nerve to subclavius

Question 16

Three Trunks split into

Answer 16

divisions

Question 17

Divisions have

Answer 17

anterior division

posterior division

Question 18

may be:

Answer 18

proximal to the clavicle or

between the clavicle and first rib

Question 19

there are no

Answer 19

branches formed off the divisions

Question 20

Three cords are:

named according to:

Answer 20

Lateral, Medial, Posterior

according to their position relative to the axillary artery (major artery to the upper limb)

Question 21

It becomes the axillary artery when:

Answer 21

the subclavian artery emerges distal-laterally from under the clavicle

Question 22

Cords generally run:

Answer 22

deep to the clavicle &

deep to the tendon of insertion of the pec minor

Question 23

Lateral cord gives off one branch

Answer 23

lateral pectoral nerve

Question 24

Medial cord gives off three branches

Answer 24

1. medial pectoral nerve
2. medial brachial cutaneous nerve
3. medial antebrachial cutaneous nerve

Question 25

medial pectoral nerve supplies:

Answer 25

pectoralis major and minor

Question 26

cutaneous nerves convey

Answer 26

sensory information from the skin only

Question 27

Posterior cord gives off three branches

Answer 27

1. upper subscapular nerve 2. thoracodorsal nerve 3. lower subscapular nerve

Question 28

Upper subscapular nerve supplies:

Answer 28

subscapularis

Question 29

Thoracodorasal nerve supplies:

Answer 29

latissimus dorsi

Question 30

Lower subscapular nerves supplies:

Answer 30

1. subscapularis | 2. teres major

Question 31

Terminal nerves how many? provide:

Answer 31

5 | provide innervation to the remainder of the upper limb

Question 32

5 Terminal Nerves

Answer 32

1. Musculocutaneous 2. Median 3. Radian 4. Axillary 5. Ulnar

Question 33

Musculocutaneous nerve derives from:

Answer 33

lateral cord

Question 34

Median nerve derives from:

Answer 34

both lateral and medial cords

Question 35

Radial and axillary nerve derive from:

Answer 35

posterior cord

Question 36

axillary nerve supplies: | then terminates:

Answer 36

supplies: teres minor and deltoid terminates: upper lateral brachial cutaneous nerve

Question 37

Spinal cord contributions to each of these terminal nerves:

Answer 37

grays anatomy pg 364

Question 38

Axillary nerve travels

Answer 38

leaves the posterior cord of plexus, runs posteriorly through the axilla, inferior to the humeral head, exits the quadrangular space to supply teres minor and deltoid, then terminates as a cutaneous nerve

Question 39

musculotaneous nerves is innervated by

Answer 39

C5 C6 C7

Question 40

Axillary nerves is innervated by

Answer 40

C5 | C6

Question 41

Radial nerve is innervated by

Answer 41

``` C5 C6 C7 C8 T1 ```

Question 42

Median nerve is innervated by

Answer 42

``` C5 C6 C7 C8 T1 ```

Question 43

Ulnar nerve is innervated by

Answer 43

C7 C8 T1

Question 44

dorsal scapular nerve

Answer 44

C5

Question 45

Long thoracic

Answer 45

C5 C6 C7

Question 46

Suprascapular nerve

Answer 46

C5 | C6

Question 47

nerve to Subclavius

Answer 47

C5 | C6

Question 48

Lateral pectoral nerve

Answer 48

C5 C6 C7

Question 49

Medial Pectoral nerve

Answer 49

C8 | T1

Question 50

Medial cutaneous of arm nerve

Answer 50

C8 | T1

Question 51

Medial cutaneous of forearm nerve

Answer 51

C8 | T1

Question 52

Superior Subscapular nerve

Answer 52

C5 | C6

Question 53

Thoracodorsal nerve

Answer 53

C6 C7 C8

Question 54

Inferior Subscapular nerve

Answer 54

C5 | C6