DR3 Forearm

Question 1

What is the common flexor origin?

Answer 1

Medial epicondyle of humerus

Question 2

What is the origin, insertion and function of palmaris longus?

Answer 2

Origin: CFO
Insertion: palmar aponeurosis
Function: flexion of wrist

Question 3

What is the palmar aponeurosis?

Answer 3

Thick sheet of dense fibrous connective tissue over central region of palm of hand

Question 4

What is the origin, insertion and function of flexor carpi radialis?

Answer 4

Origin: CFO
Insertion: Base of 2nd and 3rd metacarpal bones
Function: flexion and abduction of wrist

Question 5

What is the origin, insertion and function of flexor carpi ulnaris

Answer 5

Origin: CFO
Insertion: pisiform bone and 5th metacarpal
Function: flexion and adduction

Question 6

What is the origin, insertion and function of pronator teres?

Answer 6

Origin: CFO
Insertion: radius
Function: pronation of wrist

Question 7

What is the origin, insertion and function of flexor digitorum superficial?

Answer 7

Origin: CFO
Insertion: middle phalanges of D2-D5
Function: Flexion at metacarpophalangeal and proximal interphalangeal joint of digits 2-5, flexes at wrist

Question 8

What is the origin, insertion and function of flexor digitorum profundus?

Answer 8

Origin: Ulna
Insertion: distal phalanges of digits 2-5
Function: flexion of distal interphalangeal, metacarpophalangeal and wrist joints

Question 9

What is the origin, insertion and function of flexor pollicis longus?

Answer 9

Origin: anterior surface radius
Insertion: base of distal phalanx of digit 1
Function: flexion of thumb

Question 10

What is the origin, insertion and function of pronator quadratus?

Answer 10

Origin: Anterior surface ulna
Insertion: anterior surface radius
Function: pronate forearm

Question 11

What is flexor retinaculum?

Answer 11

Strong band of fibrous connective tissue that crosses wrist and holds tendons in place to prevent them bowing
Forms roof of carpal tunnel

Question 12

What are the superficial muscles of the flexor / anterior compartment?

Answer 12

Palmaris longus
Flexor carpi radialis
Flexor carpi ulnaris
Pronator teres
Flexor digitorum superficialis

Question 13

What are the deep muscles of the flexor / anterior compartment?

Answer 13

Flexor digitorum profundus
Flexor pollicis longus
Pronator quadrates

Question 14

What does the brachial artery branch into?

Answer 14

Radial artery

Ulna artery

Question 15

What does the ulnar artery branch into?

Answer 15

Common interosseous artery

Question 16

What does the common interosseous artery branch into?

Answer 16

Anterior interosseous artery

Posterior interosseous artery

Question 17

Describe the path of the ulnar nerve

Answer 17

Passes through cubital tunnel into forearm, under flexor carpi ulnaris.
crosses wrist to lie superficial to flexor retinaculum.
Within the hand it divides into deep and superficial branch

Question 18

What does the ulnar nerve supply?

Answer 18

Flexor carpi ulnaris
Ulnar side of flexor digitorum profundus
Intrinsic muscles of hand

Question 19

Describe the path of the median nerve

Answer 19

Enters forearm between 2 heads of pronator teres

Passes into carpal tunnel to lie superficial and deep to digital flexor tendons

Question 20

What does the median nerve supply?

Answer 20

Muscles of anterior compartment except flexor carpi ulnaris

Muscles in hand forming ball of thumb

Question 21

Describe the path of the musculocutaneous nerve

Answer 21

Enters forearm as lateral cutaneous nerve of forearm

Question 22

What does the musculocutaneous nerve supply?

Answer 22

Skin on dorsal and ventral side of forearm

Question 23

What are the superficial muscles of the poster compartment of the forearm?

Answer 23

Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
Extensor digitorum
Extensor digiti minimi
Extensor indicis

Question 24

What is the origin, insertion and function of brachioradialis?

Answer 24

Origin: lateral supracondylar ridge of humerus
Insertion: styloid process at distal end of radius
Function: flexion of forearm

Question 25

What is the origin, insertion and function of extensor carpi radialis longus?

Answer 25

Origin: lateral supracondylar ridge of humerus Insertion: base of metacarpal II Function: extend and abduct wrist

Question 26

What is the origin, insertion and function of extensor carpi radialis brevis?

Answer 26

Origin: CEO Insertion: dorsal aspect of base of 3rd metacarpal Function: extend and abduct wrist

Question 27

What is the origin, insertion and function of extensor carpi ulnaris?

Answer 27

Origin: CEO Insertion: dorsal aspect of base of metacarpal 5 Function: extend and adduct wrist

Question 28

What is the origin, insertion and function of extensor digitorum?

Answer 28

Origin: CEO Insertion: 4 tendons insert into middle and distal phalanges of digits 2-5 Function: extends proximal and distal interphalangeal joints

Question 29

What is the origin, insertion and function of extensor digiti minimi?

Answer 29

Origin: CEO Insertion: extensor hood of digit 5 Function: extension of digit 5

Question 30

What is the origin, insertion and function of extensor indicis?

Answer 30

Origin: Posterior surface ulna Insertion: extensor hood digit 2 Function: extend digit 2

Question 31

What are the deep muscles in the posterior compartment of the forearm?

Answer 31

Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus Supinator

Question 32

What is the origin, insertion and function of abductor pollicis longus?

Answer 32

Origin: interosseous membrane and posterior surface of radius and ulna Insertion: base metacarpal I Function: abducts thumb

Question 33

What is the origin, insertion and function of extensor pollicis brevis?

Answer 33

Origin: posterior surface radius Insertion: base proximal phalanx thumb Function: extend at metacarpophalangeal and carpometacarpal joints of thumb

Question 34

What is the origin, insertion and function of extensor pollicis longus?

Answer 34

Origin: posterior surface ulna Insertion: distal phalanx thumb Function: extend all joints of thumb

Question 35

What is the origin, insertion and function of supinator?

Answer 35

Origin: ulna and humerus Insertion: posterior surface radius Function: supinates forarm

Question 36

Describe the path of the radial nerve

Answer 36

Enters anterior compartment of forearm at lateral side, crosses supinator. Divides into deep and superficial branch

Question 37

Describe the path of the deep branch of the radial nerve

Answer 37

Goes to posterior interosseous nerve which pierces supinator to enter posterior compartment to supply extensors

Question 38

Describe the path of the superficial branch of the radial nerve

Answer 38

Passes down forearm under brachioradialis, deep to tendon of brachioradialis near wrist where it divides into several digital branches to supply skin on dorsolateral aspect of hand.