Neurovascular Relationships In The UE

Question 1

The axillary nerve arises from what cord in the brachial plexus?

Answer 1

Posterior cord

Question 2

What spinal cord segments are included in the axillary nerve?

Answer 2

C5-C6 ventral rami

Question 3

If the axillary nerve only has C5-C6 distributions and the radial nerve has C5-T1 distributions then the axillary nerve will be (bigger/thicker / smaller/thinner) than the radial nerve

Answer 3

smaller/thinner

Question 4

The axillary nerve runs along the ventral surface of what muscle?

Answer 4

The subscapularis

Question 5

As the axillary nerve runs across the subscapularis muscle it is running in a inferiorlateral direction and joins up with the posterior humeral circumflex artery and passes between the subscapularis, teres major, and the latissimus dorsi. This is all occurring inferior to the humeral head. So now as it is coming through that space it is moving horizontally in a posterior direction at the level of the (anatomical/surgical) neck of the humerus.

Answer 5

surgical

Question 6

As the axillary nerve moves posterior it is going to pass through the _____ space

Answer 6

quadrangular

Question 7

What are the borders of the quadrangular space superiorly, medially, inferiorly, and laterally?

Answer 7

Superiorly - teres minor
Medially - Long head of the triceps
Inferiorly - Teres major
Laterally - Surgical neck of the humerus

Question 8

What are two things that could be entrapped in the quadrangular space?

Answer 8

The posterior humeral circumflex artery and the axillary nerve

Question 9

As the axillary nerve continues on to the deltoid and innervates the deltoid there is a branch that goes on to the superoproximal portion of the arm on the lateral side. What is the name of this branch?

Answer 9

The superior lateral cutaneous nerve of the arm (brachium)

Question 10

In regard to sensory loss in the axillary nerve, what is the specific region affected?

Answer 10

Proximal posterior lateral arm

Question 11

In regard to sensory loss in the axillary nerve, what is the name of the sensory nerve/branch affected?

Answer 11

The superior lateral cutaneous nerve of the arm (brachium)

Question 12

In regard to motor loss in the axillary nerve, what are the names of the muscles that could be affected?

Answer 12

The teres minor and the deltoid

Question 13

The radial nerve is a continuation off of which cord in the brachial plexus?

Answer 13

Posterior

Question 14

The radial nerve comes off of the posterior cord and runs in an inferolateral direction off of the ventral surface of the subscapularis muscle. It will then cross the anterior aspect of the teres major and latissimus dorsi. As it crosses this area it will dive deep into the arm. From there it will go to the posterior aspect of the (arm/shoulder).

Answer 14

arm

Question 15

The radial nerve has nerve contributions from which spinal cord segments?

Answer 15

C5-T1 ventral rami

Question 16

As the radial nerve enters the posterior aspect of the arm it is coming through what is called the ____ interval

Answer 16

triangular

Question 17

What makes up the borders of the triangular interval superiorly, medially, and laterally?

Answer 17

Superiorly - Latissimus dorsi & teres major
Medially - Long head of the triceps
Laterally - Humerus

Question 18

The bulk of the radial nerve runs to the ___ groove and this is an area where the radial nerve lays right on the bone so since it is laying right on the bone it is very susceptible to injury if you have a fracture of the humeral shaft

Answer 18

spiral

Question 19

Injury to the (axillary/radial) nerve as it comes through the triangular interval is typically when you are putting weight down through the humerus in that area such as if you are on axillary crutches or resting on them improperly. You could actually be compressing the (axillary/radial) nerve or the artery that comes through there (deep brachial artery).

Answer 19

radial; radial

Question 20

A bunch of branches start to come off of the radial nerve before it ever gets to the spiral groove and that allows a number of motor fibers to get to the bulk of the ____ muscle and therefore if there is an injury to the spiral groove it is not necessarily going to disrupt that muscle significantly. It will allow the muscle to still function.

Answer 20

triceps

Question 21

The ____ nerve of the arm and the ____ nerve of the arm come off before the spiral groove so if there is injury to the humerus in that area the radial nerve will be affected but those sensory branches will not be affected.

Answer 21

inferior lateral cutaneous nerve of the arm and the posterior cutaneous nerve of the arm

Question 22

The bulk of the radial nerve enters an opening in the ____ where the radial nerve is now going to cross into the anterior compartment of the humerus

Answer 22

lateral septa

Question 23

As the radial nerve pierces that lateral intermuscular septum which is an area of entrapment it is going to enter proximal to the elbow and enters the anterior compartment between the brachialis and brachioradialis muscles. It will continue to move down the arm and at the level of the elbow. Deep to the _____ it is going to start to branch and will branch into superficial and deep radial nerves.

Answer 23

brachioradialis

Question 24

The (deep/superficial) radial nerve is going to continue to descend deep to the brachioradialis and it is going to enter the subcutaneous tissue in the distal forearm and supplies the skin of the dorsal lateral hand

Answer 24

superficial

Question 25

The deep branch of the radius passes around the neck of the radius in the supinator muscle and it is going to follow its way through across the muscle and comes out inferiorly. If the superior edge of the supinator muscle is tendinous or fibrous where the radial nerve enters, that creates what is called an ____ which is an area of entrapment.

Answer 25

arcade of frosh

Question 26

With an an arcade of frosh, this could lead to deinnervation of all of the muscles innervated (proximal/distal) to that level

Answer 26

distal

Question 27

As the deep radial nerve continues on through the supinator muscle and exits the supinator muscle it changes its name to the ___ and it continues on down running parallel with the posterior interosseous artery down the forearm, all the while branching to the different posterior forearm muscles that are deep and it will end at the posterior joint capsule of the wrist.

Answer 27

posterior interosseous nerve

Question 28

The musculocutaneous nerve is a continuation from the ___ cord in the brachial plexus

Answer 28

lateral

Question 29

The musculocutaneous nerve has contributions from which spinal cord segments?

Answer 29

C5-C7 ventral rami

Question 30

The musculocutaneous nerve pierces what muscle?

Answer 30

The coracobrachialis

Question 31

The musculocutaneous nerve descends between what two muscles?

Answer 31

The biceps brachii and the brachialis

Question 32

The musculocutaneous nerve distal and lateral to the biceps tendon becomes the _____ nerve which supplies the skin of the lateral forearm

Answer 32

lateral antebrachial cutaneous nerve

Question 33

What are the significant regions of entrapment for the musculocutaneous nerve?

Answer 33

N/A

Question 34

Any injury to the musculocutaneous nerve prior to it piercing the investing fascia would lead to sensory loss of the (half of the/entire) lateral forearm

Answer 34

entire

Question 35

Any injury proximal to the coracobrachialis would lead to loss of what muscles in the musculocutaneous nerve?

Answer 35

The coracobrachialis, biceps brachii, and brachialis

Question 36

The ulnar nerve has contributions from which spinal cord segments?

Answer 36

C7-T1

Question 37

The ulnar nerve is a continuation of the ___ cord in the brachial plexus and it descends through most of the arm in the medial neurovascular bundle

Answer 37

medial

Question 38

The (median/ulnar) nerve leaves the medial neurovascular bundle to travel to the posterior aspect of the distal arm.

Answer 38

ulnar

Question 39

As the (median/ulnar) nerve exits the anterior compartment of the arm through the medial intermuscular septum which is an area of possible entrapment, it is then going to occupy a groove which is deep in the medial head of the (biceps/triceps) which is another point of entrapment for the nerve. From there it is then going to dive posterior to the medial epicondyle of the humerus.

Answer 39

ulnar; triceps

Question 40

After diving posterior to the medial epicondyle of the humerus the ulnar nerve dives deep to the flexor carpi (radialis/ulnaris) muscle which creates a potential for entrapment.

Answer 40

ulnaris

Question 41

As the (ulnar/radial) nerve runs deep to the flexor carpi ulnaris there is going to be a dorsal cutaneous nerve that branches off proximal to the wrist and it is going to the wrist supplying the skin of the dorsal aspect of the ring and little fingers and the corresponding hand.

Answer 41

ulnar

Question 42

As the (radial/ulnar) nerve enters the wrist it is superficial to the carpal tunnel and sits superficial to the transverse carpal ligament but deep to the palmar carpal ligament. It is going to enter into the hand by going to just lateral to the pisiform and medial to the hook of the hamate. It is going to run through that area and that area is called ____ Canal which is an area of entrapment for the ulnar nerve.

Answer 42

ulnar; Guyan’s

Question 43

Once the ulnar nerve exits Guyan’s Canal it is going to branch into a superficial and deep branch. The (superficial/deep) branch is mainly cutaneous and it is going to give rise to common and proper digital nerves that supplies skin of the ventral aspect of the ring and little fingers and the corresponding hand

Answer 43

superficial

Question 44

The (superficial/deep) muscular branch of the ulnar nerve dives into the muscles of the hypothenar compartment and is going to run across from medial to lateral across the deep surface of the palm deep to the flexor tendons in where it is innervating all the muscles that it crosses.

Answer 44

deep

Question 45

The median nerve is formed by branches of the ___ cord and ____ cord from the brachial plexus and it descends through arm in medial neurovascular bundle

Answer 45

medial; lateral

Question 46

The median nerve has contributions from which spinal cord segments?

Answer 46

C5-T1

Question 47

The median nerve continues to descend in the neurovascular bundle (medial/lateral) to the brachial artery and as it enters the cubtial fossa it is going to start to incline laterally.

Answer 47

medial

Question 48

The median nerve passes between the two heads of the ___

Answer 48

pronator teres

Question 49

At the level of the pronator teres just anterior to the ulnar head we are going to see the median nerve start to branch and the branch we want to talk about here is the (anterior/posterior) interosseous branch which supplies the deep (flexor/extensor) muscles

Answer 49

anterior; flexor

Question 50

The main trunk of the median nerve passes deep to the proximal border of the FDS and descends between the ___ and the ___ muscles

Answer 50

FDS and the FDP

Question 51

The (median/ulnar) nerve is between the palmaris longus and the flexor carpi radialis, but within the carpal tunnel and joins the wrist and hands.

Answer 51

median

Question 52

There is a small branch coming off of the median nerve and is going superficial to the flexor retinaculum and that branch is the ___ branch of the median nerve and it is going to supply the skin in the area of the base of the thenar eminence.

Answer 52

palmar

Question 53

After the (median/ulnar) nerve goes through the carpal tunnel we see a recurrent branch coming off of the median nerve and that is a motor branch that supplies the muscles of the thenar compartment. From there we see a bunch of branches coming off of the median nerve. We see nerves going to the thumb, the index finger, the middle finger, and the radial part of the ring finger. And those are common and proper digital nerves supply the skin in the hand.

Answer 53

median

Question 54

The brachial artery is a direct continuation of __ artery at inferior border of teres major and it descends through the arm in the medial neurovascular bundle. As it goes down the arm and moves laterally to the cubital fossa we see it crossing the cubital fossa medial to the biceps tendon and lateral to the median nerve. As it enters the cubital fossa before it reaches the pronator teres muscle we should see it bifurcating into a lateral (radial/ulnar) artery and a medial (radial/ulnar) artery.

Answer 54

axillary; radial; ulnar

Question 55

After the brachial artery bifurcates into a radial and ulnar arteries, the radial artery continues laterally and runs deep to the _____ muscle right along with the superficial branch of the radial nerve. As it gets closer to the wrist it is in a position just lateral to the flexor carpi radialis muscle and as the artery gets closer to the wrist it is going to incline dorsally.

Answer 55

brachioradialis

Question 56

The (radial/ulnar) artery enters the anatomical snuffbox and passes to the dorsum of the hand. The (radial/ulnar) artery starts to branch as it crosses the wrist.

Answer 56

radial; radial

Question 57

As the main part of the radial artery enters the hand you are going to see it branch off in the first web space and it is going to give rise to the (superficial/deep) palmar arterial arch as it dives through that web space and will be the main contributor to the (superficial/deep) palmar arterial arch and palmar metacarpal arteries running from the radial side of the hand to the ulnar side of the hand and it will be completed by the deep branch of the ulnar artery.

Answer 57

deep; deep

Question 58

The (radial/ulnar) artery descends deep to the flexor carpi ulnaris

Answer 58

ulnar

Question 59

Coming off of the ulnar artery in the proximal forearm almost immediately, we see this common interosseous artery that branches into an anterior interosseous artery and a posterior interossoues artery and each artery each descends on their respective side of the ____ membrane.

Answer 59

interosseous

Question 60

As the ulnar artery follows the flexor carpi ulnaris at the wrist level it is going to enter the hand passing laterally to the pisiform bone and medial to the hook of the hamate and is splitting into ___ and ____ branches of the ulnar artery.

Answer 60

superficial and deep

Question 61

As the (superficial/deep) branch of the ulnar artery enters the hand main contributor to superficial palmar arterial arch and it gives rise to common and proper digital branches. The arch is completed by superficial branch of the radial artery

Answer 61

superficial

Question 62

The (superficial/deep) branch of the ulnar artery passes through the hypothenar compartment and travels across the palm in the lateral to medial direction and deep to the long flexor tendons.

Answer 62

deep

Question 63

What are the possible sites of entrapment for the median nerve?

Answer 63

The pronator teres muscle, sublimus bridge, and the carpal tunnel

Question 64

What are the possible sites of entrapment for the ulnar nerve?

Answer 64

• Medial intermuscular septum
• Medial head of the triceps
• posterior to medial epicondyle & deep to FCU
• Ulnar Tunnel/Guyan’s Canal