nerve supply to the upper limb

Question 1

how many pairs of spinal nerves arise along the spinal cord?

Answer 1

31

Question 2

how many pairs of spinal nerves are located in the cervical region of the cord?

Answer 2

8 pairs in the cervical region

Question 3

how many pairs of spinal nerves are located in the thoracic region of the cord?

Answer 3

12 pairs in the thoracic region

Question 4

how many pairs of spinal nerves are located in the lumbar area?

Answer 4

5 pairs in the lumbar area

Question 5

how many pairs of spinal nerves are located in the sacral area?

Answer 5

5 pairs in the sacral area

Question 6

how many pairs are located in the coccygeal region?

Answer 6

1 pair in the coccygeal region

Question 7

what are the branches of spinal nerves called?

Answer 7

Rami

Question 8

Name the two origins of spinal nerves

Answer 8

1. Anterior (ventral) root of the spinal cord
2. Posterior (dorsal) root of the spinal cord

Question 9

Spinal nerves are “mixed” nerves.

What does this mean?

Answer 9

each contain both sensory and motor axons

Question 10

where do the sensory axons pass through before reaching the spinal cord itself?

Answer 10

the dorsal root ganglion, where their cell bodies are located

Question 11

where do the motor axons pass through before meeting the sensory axons to form the mixed nerves?

Answer 11

the ventral roots

Question 12

Where does the Brachial plexus supply nerves?

Answer 12

the shoulders and upper limbs

Question 13

What rami (branches of spinal nerves) form the nerve “braid” that is the Brachial plexus?

Answer 13

the anterior rami of C5-C8 & T1 form the Brachial plexus

Question 14

Name the important nerves that arise from the brachial plexus

Mnemonic?: all muscles radiate, median, ulnar
(idk :( I can’t think of a good one)

Answer 14

Axillary nerve
Musculocutaneous nerve
Radial nerve
Median nerve
Ulnar nerve

Question 15

Name the subunits of the brachial plexus

Mnemonic: Risk Takers Don’t Cautiously Behave

Answer 15

Roots
Trunks
Divisions
Cords
Branches

Question 16

The wrist is extended using extrinsic muscles in the posterior compartment of the forearm to release an object in the hand.

What is the main nerve supporting this movement?

Answer 16

The Radial nerve

Question 17

The wrist is flexed using extrinsic muscles in the anterior compartment of the forearm to hold/grip an object in the hand.

What is the main nerve supporting this?

Answer 17

The Median nerve

Question 18

Which nerves support precision grips of the hand using mainly intrinsic muscles of the hand?

Answer 18

A combination of the Median and Ulnar nerves

Question 19

The Axillary nerve arises from the POSTERIOR cord of the Brachial Plexus.

What does it supply?

Answer 19

• Deltoid
• Teres minor

Question 20

The Musculocutaneous nerve arises from the LATERAL cord of the Brachial Plexus.

What does it supply?

Answer 20

• Coracobrachialis
• Biceps brachii
• Brachialis (medial 2/3rds)

Question 21

The Ulnar nerve arises from the MEDIAL cord of the Brachial Plexus.

What does it supply?

Answer 21

• Flexor carpi ulnaris
• Flexor DigProf (medial ½)
• Deep branch, intrinsic
  muscles:
  Flexor and abductor DM, Opponens DM, medial 2 lumbricals, palmar and dorsal interossei, abductor pollicis

Question 22

The Radial nerve arises from the POSTERIOR cord of the Brachial Plexus.

What does it supply?

Answer 22

Triceps, anconeus, brachialis.
Brachioradialis, extensor
CarRadLong

• Deep branch (posterior interosseus nerve):
• Supinator, Ext.CRB, Ext.Dig, Ext.Dig.Min, Ext.CU, Ext.Pol.LandBrevis, Ext.Indicis, Abd.Pol.Long

Question 23

The Median nerve arises from MEDIAL and LATERAL cords of the Brachial plexus.

What does it supply?

Answer 23

Pronator teres, FlexCR, Palmaris longus, FlexDigSup, Abductor and flexor PB,
opponens pollicis, lateral 2 lumbricals

• Deep branch (anterior
  interosseus nerve):
• FlexPol.Lon, FlexDProf, pronator quadratus