Brachial Plexus

Question 1

All of the nerves for the upper extremity arise from the:

Answer 1

brachial plexus

Question 2

Brachial plexus

Answer 2

a network of nerves that practically provides full sensory and motor innervation to the arm

Question 3

Where does the axillary artery originate?

Answer 3

continuation of the subclavian artery

Question 4

What is the extent of the axillary artery?

Answer 4

extends from outer border of 1st rib to lower border of teres major

Question 5

What does the radial nerve innervate?

Answer 5

all extensors!

Question 6

Injury of the radial nerve in the axilla typically results in:

Answer 6

wrist drop

Question 7

Injury of the radial nerve would result in sensory loss on:

Answer 7

• posterior surface of the lower part of the arm
• down a narrow strip on the back of the forearm
• lateral part of the dorsum
• dorsal surface of the roots of the lateral 3.5 fingers

Question 8

Axillary nerve extends from which spinal nerves?

Answer 8

C5 and C6

Question 9

Axillary is a terminal branch of which cord?

Answer 9

posterior

Question 10

The axillary nerve passes through the _____ ______ in the axilla with the posterior circumflex humeral artery around the surfical neck of the humerus

Answer 10

quadrangular space

Question 11

Motor functions of the axillary nerve

Answer 11

innervate deltoid muscle and teres minor

Question 12

Sensory innervation of the axillary nerve

Answer 12

skin over the shoulder

Question 13

Three ways the axillary nerve is usually injured

Answer 13

• fracture of surgical neck of humerus
• downward dislocation of the shoulder joint
• compression from the incorrect use of crutches

Question 14

The loss of cutaneous sensation is consistent with an injury to the _____ nerve.

Answer 14

radial

Question 15

The difficulty extending at the wrist and elbow is also consistent with a ______ nerve injury

Answer 15

radial

Question 16

Which nerve is the largest branch of the lateral cord?

Answer 16

musculocutaneous nerve

Question 17

Which muscles does the musculocutaneous nerve innervate?

Answer 17

• biceps brachii
• brachialis
• coracobrachialis

Question 18

Where does the musculocutaneous nerve end on the forearm?

Answer 18

ends on the forearm as lateral cutaneous nerve of the forearm

Question 19

An injury to the __________ nerve is relatively uncommon, as it is well protected within the axilla.

Answer 19

musculocutaneous

Question 20

The most common cause of musculocutaneous injury

Answer 20

stab wound to the axilla region

Question 21

Loss of motor functions of the musculocutaneous nerve

Answer 21

• weak flexion at the shoulder
• weak flexion at the elbow
• supination greatly affected

Question 22

The axillary nerve arises directly from which part of the brachial plexus

Answer 22

posterior cord

Question 23

Where does the median nerve derive from?

Answer 23

lateral and medial cords (C6-T1)

Question 24

Motor supply of the median nerve

Answer 24

• flexor muscles in the forearm except flexor carpi ullnaris and the ulnar head of flexor digitorum profundus
• muscles of the thenar eminence and the radial two lumbricals

Question 25

Sensory supply of the median nerve

Answer 25

skin of

• palmar and distal dorsal aspects of the lateral three-and-the-half digits and adjacent palm
• palmar and distal dorsal aspects of the thumb and radial half of 2nd digit
• palmar and distal dorsal aspects of the adjacent sides of 2nd-4th digits
• central palm

Question 26

What nerve is also known as the “million-dollar nerve” to signify its importance of basic hand function

Answer 26

median

Question 27

Conditions associated with median nerve damage

Answer 27

• carpal tunnel syndrome
• hand of benediction
• ape hand deformity

Question 28

Where does the ulnar nerve lie?

Answer 28

on the medial side of axillary artery

Question 29

Where does the ulnar nerve descend?

Answer 29

down the medial aspect of the arm, medial to biceps brachii and anterior brachialis

Question 30

The ______ nerve can broadly be described as the nerve of the hand, as the nerve innervates the vast majority of the intrinsic hand muscles.

Answer 30

ulnar