Neurovasculature of the Upper Limb

Question 1

The superficial lymph vessels of the upper limb that drain the lateral side and the lateral two digits accompany the ___(1)___ vein and drain into the ____(2)____ lymph nodes. Those from the medial side of the limb accompany the ____(3)____ vein and drain into the ___(4)___ group of axillary nodes. Some of the medial lymph vessels terminate in the ____(5)____ lymph nodes, situated just above the medial epicondyle. A few lymph vessels that drain the thumb end in the ____(6)____ lymph nodes.

Answer 1

(1) cephalic vein
(2) infraclavicular axillary nodes
(3) basilic
(4) lateral
(5) supratrochlear/epitrochlear
(6) deltopectoral
[Diagram]

Question 2

The deep veins lie deep to muscles and accompany arteries as _____________________.

Answer 2

venae comitantes

Question 3

Where are the superficial veins absent, and why?

Answer 3

• palm
• along the ulnar border of the forearm
• back of the elbow

REASON: These are pressure sites.

Question 4

Which veins comprise the superficial veins?

Answer 4

• dorsal venous arch
• cephalic vein
• basilic vein
• median cubital vein

Question 5

List the tributaries of dorsal venous arch.

Answer 5

• three dorsal metacarpal veins
• a dorsal digital vein from the medial side of little finger
• a dorsal digital vein from the lateral side of the index finger
• two dorsal digital veins of the thumb
• veins draining palm of hand: (a) veins that pass around the margins of the hand, (b) perforating veins, which pass dorsally through the interosseous spaces

Question 6

The dorsal venous arch drains into ___________ and ____________ veins - the efferent vessels of dorsal venous arch.

Answer 6

cephalic and basilic

Question 7

Briefly describe the course of the cephalic vein.

Answer 7

1. Arises from anatomical snuffbox, originating from the radial side of the superficial venous network of the dorsum of the hand.
2. Arches around the radial aspect of the distal forearm.
3. Courses through the anterolateral forearm.
4. Passes upwards over the anterior elbow region.
5. Ascends through the anterolateral arm, lateral to the biceps muscle in the deltopectoral groove, formed by the adjacent borders of the deltoid and pectoralis major muscles.
6. Passes through the anterior wall of the axilla, perforating the clavipectoral fascia to drain into the first part of the axillary vein.

Question 8

Cephalic vein is accompanied by the lateral cutaneous nerve of the forearm, and the terminal part of the radial nerve. TRUE or FALSE.

Answer 8

TRUE

Question 9

Briefly describe the course of the basilic vein.

Answer 9

1. Begins from the medial end of the dorsal venous arch.
2. It runs upwards along the back of the medial border of the forearm,
3. Winds round this border near the elbow,
4. Continues upwards in front of the elbow (medial epicondyle) and along the medial margin of the biceps brachii up to the middle of the arm, where
5. It pierces the deep fascia, and
6. Runs along the medial side of the brachial artery up to the lower border of teres major where it becomes the axillary vein.
7. [Diagram]

Question 10

Discuss the median cubital vein. (function, course)

Answer 10

It is a communicating venous channel between the cephalic and basilic veins, which shunts blood from the cephalic vein to the basilic vein.
It begins from the cephalic vein, 2.5 cm below the elbow bend, runs obliquely upwards and medially to end in the basilic vein, 2.5 cm above the bend of elbow.

Question 11

State the important features/landmarks of the median cubital vein. (4)

Answer 11

1. It is separated from brachial artery by the bicipital aponeurosis.
2. It communicates with the deep veins through a perforator vein, which pierces the bicipital aponeurosis.
3. It receives median vein of the forearm [variable; the median antebrachial vein may also drain into basilic/cephalic vein].
4. It shunts blood from cephalic vein to the basilic vein.

Question 12

Briefly describe the course of the median vein of the forearm.

Answer 12

Median vein of the forearm begins from palmar venous network, runs upwards in the midline on the anterior aspect of forearm to end in any one of three veins in front of elbow (viz. cephalic, basilic, and median cubital veins).

Question 13

In 30% of cases, the median cubital vein is absent. In this case, what do we see?

Answer 13

The upper end of median vein of the forearm bifurcates into the median cephalic and median basilic veins, which join the cephalic and basilic veins, respectively.

Question 14

What do the deep veins of the upper limb comprise of?

Answer 14

(a) venae comitantes, which accompany the large arteries such as radial, ulnar, and brachial arteries
(b) axillary vein

Question 15

Venae comitantes of the radial and ulnar arteries accompany the radial and ulnar arteries, respectively, and join to form the _____________________.

Answer 15

brachial veins
[Diagram: veins of the upper limb]

Notes:
The brachial veins are usually 2 in number and they are located on either side of the brachial artery. They are usually formed by the union of the radial and the ulnar venae comitantes, near the level of the elbow.

Question 16

Venae comitantes of the brachial artery are small veins, one on each side of the brachial artery. They join _______[1]_______ at the lower border of the teres major muscle. The medial one often joins the ______[2]________.

Answer 16

[1] axillary vein
[2] basilic vein

Question 17

(a) Axillary vein begins as a continuation of basilic vein at the lower border of ____(I)____ and runs through axilla, passes through its apex to continue as ____(II)____ at the outer border of the first rib.
(b) Which two veins unite to form axillary vein?

Answer 17

(a) (I) teres major, (II) subclavian vein
(b) basilic and brachial veins

Question 18

Into which group of lymph nodes do the deep lymph vessels drain into?

Answer 18

lateral group of axillary lymph nodes

Question 19

List the superficial lymph nodes of the upper limb.

Answer 19

1) Infraclavicular nodes - drain lymph from thumb including its web and also upper part of the breast
2) Deltopectoral node - drains the lymph from the breast and adjoining small structures
3) Superficial cubital/supratrochlear nodes - drain the lymph from the ulnar side of the hand and forearm
4) [Diagram: superficial and deep lymph nodes of the upper limb]

Question 20

List the deep lymph nodes of the upper limb.

Answer 20

(a) Axillary lymph nodes
(b) A few other deep lymph nodes:
- along the medial side of the brachial artery
- in the cubital fossa, at the bifurcation of the brachial artery (called deep cubital node)
- occasionally along the arteries of the forearm

Question 21

a) The thyrocervical trunk is a branch of which part of the subclavian artery?
b) Which branches from the thyrocervical trunk contribute to scapular anastomosis?

Answer 21

a) first part
b) Suprascapular artery, dorsal scapular artery (deep branch of transverse cervical artery)

Note that the dorsal scapular artery may arise from the third part of the subclavian artery.

Question 22

Review the parts and branches of the axillary artery.

Answer 22

1st part: Supreme thoracic artery - runs anteromedially along superior border of pectoralis minor then passes between it and pectoralis major to thoracic wall

2nd part:
(a) medial branch - thoracoacromial artery, dividing into pectoral, deltoid, acromial and clavicular branches
(b) lateral branch - lateral thoracic artery

3rd part: subscapular artery (which gives off circumflex scapular artery), as well as anterior and posterior circumflex humeral arteries

Question 23

State the origin of the brachial artery.

Answer 23

lower border of teres major muscle as a continuation of the axillary artery

Question 24

Where and how does the brachial artery terminate?

Answer 24

at the level of neck of radius by dividing into radial and ulnar arteries

Question 25

Branches of brachial artery? (6)

Answer 25

a) Muscular branches to the muscles of the anterior compartment of arm
b) Profunda brachii artery (largest and first branch)
c) Nutrient artery to humerus
d) Superior ulnar collateral artery
e) Inferior ulnar collateral artery/supratrochlear artery
f) Radial and ulnar arteries (terminal branches)

Question 26

Briefly discuss Volkmann’s ischemic contracture (ischemic compartment syndrome). (definition, causes)

Answer 26

This is a permanent contracture of the hand and wrist, resulting in a claw - like deformity of the hand and fingers.

It is caused by the sudden complete occlusion (e.g. due to a tight plaster cast or compartment syndrome) or laceration (due to supracondylar fracture of the humerus) of the brachial artery, resulting in ischemia of the muscles of the forearm. The muscles can tolerate ischemia for up to 6 hours only. Thereafter, they undergo necrosis and fibrous tissue replaces the necrotic tissue. As a result, muscles shorten permanently producing a flexor deformity characterized by flexion of the wrist, extension of the metacarpophalangeal joints, and flexion of the interphalangeal joints, which leads to loss of hand power.

Question 27

In the arm, the median nerve lies ____(1)____ (medial/lateral) to the brachial artery. It then crosses the artery from ____(2)____ (medial to lateral/lateral to medial) at the mid-humeral point (at the level of insertion of coracobrachialis). After crossing, it runs downwards to enter the cubital fossa by passing between the two heads of ____(3)____. It leaves the cubital fossa, crossing the ____(4)____ artery (from medial to lateral) from which it is separated by ____(5)____. Then, along with the ulnar artery, it passes beneath the fibrous arch joining the two heads of ____(6)____ and runs deep to this muscle on the surface of ____(7)____.

Answer 27

1. lateral
2. lateral to medial
3. pronator teres
4. ulnar
5. deep head of pronator teres
6. flexor digitorum superficialis
7. flexor digitorum profundus
8. [Diagram 1]

Question 28

Name two neurovascular structures that pass between the two heads of flexor carpi ulnaris.

Answer 28

1. ulnar nerve
2. posterior ulnar recurrent artery

Question 29

What structures pass through the deltopectoral groove?

Answer 29

cephalic vein
deltoid branch of thoracoacromial artery

Question 30

State the branches of ulnar artery.

Answer 30

1. Muscular branches
2. Common interosseous artery, dividing into anterior, posterior, and recurrent interosseous arteries
3. Anterior and posterior ulnar recurrent arteries
4. Palmar carpal branch
5. Terminal branches: superficial palmar arch, deep palmar branch
6. [Diagram]

Question 31

State the branches of radial artery.

Answer 31

1. Radial recurrent artery
2. Muscular branches
3. Palmar carpal branch
4. Deep palmar arch and superficial palmar branch
5. Princeps pollicis and radialis indicis (terminal branches)
6. [Video (4 mins)]

Question 32

Name two neurovascular structures that pass below the ligament of Struthers. What is the clinical significance of this?

Answer 32

1. brachial artery, median nerve
2. site of entrapment of median nerve

Question 33

The radial nerve arises from the ____(a)____ cord of the brachial plexus in the axilla. It leaves the axilla through the ____(b)____ space. It then winds around the back of the arm to enter the ____(c)____ of the humerus between the ____(d)____ and ____(e)____ heads of triceps, accompanied by ____(f)____. It leaves the ____(c)____ by piercing the ____(g)____ of the arm.

The radial nerve gives a branch to ____(h)____ head of triceps brachii in the axilla. While passing through the spiral groove, it gives the following 5 branches (3 motor, 2 sensory): ____(i)____. After passing through ____(h)____, it descends between ____(j)____ and ____(k)____ muscles, arriving at the level of the cubital fossa. Above the lateral epicondyle, it gives branches to brachoradialis, extensor carpi radialis longus and a small lateral part of ____(l)____. At the level of the lateral epicondyle (variable), the radial nerve terminates by giving two branches, the superficial (sensory) and the deep (motor) radial nerve.

Answer 33

(a) posterior
(b) lower triangular
(c) spiral/radial groove
(d) lateral (and) (e) medial
(f) profunda brachii artery
(g) lateral intermuscular septum
(h) long
(i) nerves to lateral and medial heads of triceps, nerve to anconeus, posterior brachial and antebrachial cutaneous nerves
(j) brachialis (and) (k) brachoradialis
(l) brachialis

Question 34

State the extents of the axillary artery.

Answer 34

The axillary artery commences from the subclavian artery at the lateral border of the first rib and terminates when it becomes the brachial artery at the inferior border of teres major.

Question 35

State 4 sites of entrapment of radial nerve

Answer 35

Arcade of Frohse
Radial groove/spiral groove
Lateral intermuscular septum
Between brachialis & brachioradialis
Supinator

Question 36

What anatomical events are associated with the following nerves at the level of the insertion of coracobrachialis.
1. ulnar nerve
2. radial nerve
3. median nerve
4. medial antebrachial cutaneous nerve

Answer 36

1. Ulnar nerve pierces medial intermuscular septum to go into posterior compartment of the arm
2. Radial nerve pierces lateral intermuscular septum to enter anterior compartment of the arm
3. Median nerve crosses in front of brachial artery from lateral to medial
4. Medial antebrachial cutaneous nerve pierces the deep fascia

Question 37

Describe the formation of the superficial and deep palmar arterial arches of the hand.

Answer 37

1. Superficial palmar arterial arch is formed by anastomosis between the direct continuation of the ulnar artery with the small superficial palmar branch of the radial artery.
2. The deep palmar arterial arch is formed by anastomosis between the direct continuation of the radial artery with the small deep palmar branch of the ulnar artery.

Question 38

Name the terminal branches of the radial artery.

Answer 38

1. princeps pollicis
2. radialis indicis
3. deep palmar arch

Question 39

The carpal tunnel is a potential site of compression of the median nerve. What are some pathological conditions that may cause narrowing of the carpal tunnel?

Answer 39

1. tenosynovitis of flexor tendons
2. myxedema
3. retention of fluid in pregnancy
4. fracture dislocation of lunate bone
5. osteoarthritis of the wrist

Extra notes:
What is tenosynovitis? This refers to the inflammation of a tendon and its synovial sheath.
Myxedema: deficiency in thyroxine
Osteoarthritis: degenerative joint disease in which tissues in the joint break down over time, esp, articular cartilage

Question 40

In the axilla, the radial nerve may be injured by the pressure due to the upper end of a crutch (crutch palsy). Comment on the motor loss a patient with crutch palsy may experience.

Answer 40

1. loss of extension of the elbow due to paralysis of triceps brachii
2. loss of extension of the wrist due to paralysis of wrist extensors (this causes wrist drop due to unopposed action of flexor muscles of the forearm)
3. loss of extension of digits due to paralysis of extensor digitorum, extensor indicis, extensor digiti minimi, and extensor pollicis longus
4. loss of supination of extended elbow since supinator and brachoradialis are paralysed

Question 41

Describe the course and motor distribution of the of the ulnar nerve (8 marks)

Answer 41

Course of ulnar nerve (Any 6 for 6 marks):
 Arise from the medial cord in the axilla
 Run in the medial aspect of the anterior arm
 Pierce the medial intermuscular septum to go to posterior compartment
 Pass behind the medial humeral epicondyle
 Pass through the cubittal tunnel (formed by the origin of FCU)
 Run with ulnar vessels deep to FCU in the forearm
 Pass superficial to the flexor retinaculum at the wrist/pass through the canal
of Guyon

Motor distribution (2 marks)
 FCU and FDP in the forearm
 All intrinsic muscles of the hand apart from thenar and 1st two lumbricals

Question 42

[14:53 minute video]; review of ulnar nerve on the cadaver+clinical anatomy of ulnar nerve

Answer 42

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