Vessels and Nerve of the Forearm

Question 1

Radial artery

Answer 1

• exits cubital fossa deep to brachioradialis and superficial to pronator teres
• runs distally with superficial branch of radial nerve on surface of flexor forearm muscles
• passes deep to tendons in anatomical snuff box and runs on dorsum

Question 2

Branches of radial artery

Answer 2

1. radial reccurent artery
2. muscular branches
3. palmar carpal branch
4. superficial palmar branch

Question 3

Radial recurrent artery

Answer 3

• branches laterally
• accompanies radial nerve between brachialis and brachioradialis
• anastomose with radial collateral branch of deep brachial artery

Question 4

Muscular branches of radial artery

Answer 4

• distributed along entire length of artery

Question 5

Palmar carpal branch of radial artery

Answer 5

• arises near distal border or pronator quadratus
• courses medially across wrist
• anastomose with with palmar carpal branch of ulnar artery and anterior interosseous branches

Question 6

Superficial branch

Answer 6

• arises before radial artery passes to dorsum of hand

- helps for superficial palmar arterial arch

Question 7

Ulnar Artery

Answer 7

• exits cubital fossa deep to pronator teres
• accompanies median nerve
• between flexor digitorum superficial is and flexor digitorum profundus
• distal 1/2 forearm accompanies ulnar nerve- overlapped by flexor carpi ularnis
• passes superficial to flexor retinaculum
• primary contributor of superficial palmar arch

Question 8

branches from ulnar artery

Answer 8

1. anterior ulnar recurrent
2. posterior ulnar recurrent
3. common interosseous
4. muscular branches
5. palmar carpal branch
6. dorsal carpal branch
7. deep palmar branch

Question 9

Anterior ulnar recurrent artery

Answer 9

• arises medial
• passes anterior to medial epicondyle bt pronator teres and brachialis
• anastomose with inferior ulnar collateral from brachial artery

Question 10

posterior ulnar recurrent artery

Answer 10

• arises medial distal to anterior ulnar recurrent
• passes posterior to medial epicondyle
• anastomose with superior ulnar collateral from brachial artery

Question 11

Common interosseous artery

Answer 11

• arises laterally from ulnar artery before it leaves cubital fossa
• courses deeply
• when reaches interosseous membrane divides into anterior and posterior interosseous arteries

Question 12

Anterior interosseous artery

Answer 12

• courses anterior to surface of interosseous membrane
• passes deep to pronator quadrates
• travels with anterior interosseous median nerve
• provides muscular branches and palmar branches (joins palmar carpal network)
• pierces interosseous membrane distally to join posteroir interosseous artery

Question 13

Posterior interosseous artery (PIA)

Answer 13

• courses posterior between radius and ulna
• travels with deep branch of radial nerve (aka posterior interosseous nerve) bt superficial and deep layers
• at carpus PIA joins with anterior interosseous artery
• anastomose with dorsal carpal branches of radial and ulnar arteries to form dorsal carpal arch
• has one branch (interosseous recurrent)

Question 14

Interosseous recurrent artery

Answer 14

• only brach of PIA

- anastomose with middle collateral branch of deep brachial artery

Question 15

Muscular branch of ulnar artery

Answer 15

• given off along entire ulnar artery

Question 16

palmar carpal branch of ulnar artery

Answer 16

• courses wrist laterally
• forms palmar carpal network
• deep to tendons of flexor digitorum profundus

Question 17

dorsal carpal branch of ulnar artery

Answer 17

• winds medially deep to tendon of flexor carpi ulnaris
• goes to back of wrist deep to extensor tendons
• forms dorsal carpal arch

Question 18

deep palmar branch of ulnar artery

Answer 18

• branches at wrist
• deep to pisohamate ligament
• enter hypothenar muscles
• minor contributor of deep palmar arterial arch

Question 19

viens of radial and ulnar arteries

Answer 19

• venae comitantes of arteries

Question 20

Median nerve in forearm

Answer 20

• enters forearm medially to brachial artery
• accompanies ulnar artery bt flexor digitorum superficialis and profundus
• superficial at wrist
• 2 types of innervation
  1. articular branches- elbow joint
  2. muscular branches- all muscles in anterior forearm (except flexor carpi ulnaris)
  3. palmar cutaneous branches- last branch of median nerve

Question 21

anterior interosseous nerve

Answer 21

• branches from median nerve within cubital fossa
• courses anterior surface of interosseous membrane
• accompanies anterior interosseous artery and innervates muscles in deep layer (flexor digitorum profudus, flexor pollicis longs, pronator quadrates)
• terminates with branches to ventral carpal articulations

Question 22

Carpal Tunnel Syndrome

Answer 22

• inflammation and edema within carpal tuner
• compresses median nerve
• results in pain, parathesias within cutaneous distribution of median nerve, and weakness of thenar eminence muscles

Question 23

Ulnar Nerve

Answer 23

• courses posterior to medial epicondyle of humerus
• enters forearm between two heads of origin of flexor carpi ulnaris
• joins ulnar artery mid forearm
• enters wrist through guyons tunnel
  Distribution:
  1. articular branches to elbow joint
  2. muscular branches flexor ulnaris and profundus medially
  3. cutaneous branches to hand which arise in forearm

Question 24

canal of struthers

Answer 24

• fasia connecting two head of flexor carpi ulnaris
• forms cubital tunnel
• 1st site of compression for ulnar nerve

Question 25

Guyon's Tunnel

Answer 25

- formed from piso-hamate ligament - composed of superficial portion of flexor retinaculum between hamate and pisiform - nerve divides into superficial and deep ulnar nerve - 2nd site of compression of ulnar nerve

Question 26

Superficial branch of radial nerve

Answer 26

- courses through anterior forearm under brachioradialis - joins radial artery medially - goes to back of hand by passing through anatomical snuffbox - inner ate skin of lateral back of hand, thumb, ring and middle fingers

Question 27

Deep branch of radial nerve

Answer 27

- pierces and winds around radius within supinator to go to posterior of forearm - joined by posterior interosseous artery - exits supinator in deep posterior compartment of extensor forearm as many branches - majority of branches supply deep extensor muscles - terminal portion= posterior interosseous nerve

Question 28

Radial nerve branches

Answer 28

1. superficial branch | 2. deep branch

Question 29

posterior interosseous nerve

Answer 29

- terminal portion of deep branch of radial nerve - courses dorsal surface of interosseous membrane with posterior interosseous artery - terminate by providing branches to dorsal carpal articulation