Arm and Forearm

Question 1

Describe some features of the arm

Answer 1

4 muscles
2 fascial compartments
3 large nerves

LARGE MEDIAL neurovascular bundle

Question 2

State the muscles in the anterior arm

Answer 2

Biceps brachii
Coracobrachialis
Brachialis

Question 3

Describe a feature of the biceps brachii

Answer 3

2 heads - Long head + Short head

Question 4

Where do the heads of the biceps brachii attach ?

Answer 4

Short head attaches to the coracoid process of the scapula

Long head attaches to the supraglenoid tubercle of the scapula

Question 5

Where do the heads of the biceps brachii insert ?

Answer 5

The 2 heads insert into the forearm via 2 different things :

• Radial tuberosity
• Bicipital Aponeurosis

Question 6

State the innervation of the biceps brachii muscle

Answer 6

Musculocutaneous nerve
C5,6,7 (MAINLY C6)

Question 7

State the movement of the biceps brachii

Answer 7

Supination - then flexion (synergist in elbow flexion)

Short head associated with stability

Question 8

Describe features of the coracobrachialis

Answer 8

Goes from the coracoid process to the arm.
Runs alongside the short head of biceps

Question 9

Where does the coracobrachialis attach ?

Answer 9

The coracoid process of the scapula

Question 10

State the innervation of the coracobrachialis muscle

Answer 10

Musculocutaneous nerve
C5,6,7 (MAINLY C6)

Question 11

State the movement of the coracobrachialis muscle

Answer 11

Flexion, adduction at GH joint

Associated with stability

Question 12

State the movement of the brachialis muscle

Answer 12

Prime mover in elbow flexion.

Question 13

State the attachment of the brachialis muscle

Answer 13

The anterior surface of the humerus

Question 14

State the insertion of the brachialis muscle

Answer 14

The coronoid process of the ulna

Question 15

State the innervation of the brachialis muscle

Answer 15

Musculocutaneous nerve
C5,6

Question 16

What does the musculocutaneous nerve become in the forearm ?

Answer 16

It becomes the lateral cutaneous nerve of the forearm.

Question 17

What is the biceps reflex ?

Answer 17

Deep tendon reflex

Afferents from muscle spindles
Efferent alpha motor neurons

Question 18

Function of the biceps reflex test

Answer 18

Tests C5 and C6 spinal segments
Elicits a flexion jerk

Question 19

State the muscle(s) in the posterior arm

Answer 19

Triceps brachii (has 3 heads)

• Long head
• Lateral head
• Medial head

Question 20

Where do the heads of the triceps brachii insert ?

Answer 20

All 3 heads come together and insert onto the olecranon process of the ulna.

Question 21

State the innervation of the triceps brachii

Answer 21

The radial nerve
C6,7,8 (MAINLY C7 and 8)

Question 22

Describe the movements associated with the triceps brachii

Answer 22

Extensor of the elbow

Long head - shoulder extension (associated with stability)

Question 23

What nerve supplies the anterior arm compartment ?

Answer 23

Musculocutaneous nerve

Question 24

What nerve supplies the posterior arm compartment ?

Answer 24

Radial nerve

Question 25

What happens due to damage of the radial nerve ?

Answer 25

Paralysis in the muscles of the posterior forearm. - Wrist drop (floppy wrist)

Question 26

Function of the triceps reflex test

Answer 26

Tests C6 and C7 (C8) spinal segments Elicit an extension jerk

Question 27

State features of the cubital fossa

Answer 27

Area anterior to the elbow Borders Roof Floor Contents

Question 28

State the borders of the cubital fossa

Answer 28

Pronator teres Brachioradialis Line between the lateral and medial epicondyles (this forms a triangle called the cubital fossa)

Question 29

State the roof of the cubital fossa

Answer 29

Bicipital aponeurosis

Question 30

State the contents of the cubital fossa

Answer 30

From medial to lateral : - Median nerve - Brachial artery - Biceps tendon - Radial nerve

Question 31

What is different about the radial nerve at the cubital fossa ?

Answer 31

Normally the radial nerve runs posteriorly but at the cubital fossa is come anteriorly at the elbow. It branches into a deep and superficial branch. The deep branch dives through the supinator muscle deep.

Question 32

State the floor of the cubital fossa

Answer 32

- Supinator - Brachialis

Question 33

What structures is found superficial to the cubital fossa ?

Answer 33

The median cubital vein

Question 34

What is the anterior forearm innervated by ?

Answer 34

Median nerve (except 1 1/2 muscles by the ulnar nerve)

Question 35

What is the posterior forearm innervated by ?

Answer 35

Radial nerve

Question 36

Movements of the anterior forearm

Answer 36

Flexors and Pronators *common flexor origin

Question 37

State the layers of the anterior forearm

Answer 37

Superficial Intermediate Deep

Question 38

State the contents of the superficial layer of the anterior forearm

Answer 38

Contains the following muscles : Pronator teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris

Question 39

State the superficial muscle of the anterior forearm located laterally

Answer 39

Pronator teres C6,7 (mainly C7) (located near the thumb)

Question 40

State the order of the superficial muscles of the anterior forearm (from lateral to medial)

Answer 40

Pronator teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris

Question 41

What is unique about palmaris longus ?

Answer 41

C7,8 - Absent in around 15% of people - Evolutionary change

Question 42

Where does the palmaris longus insert ?

Answer 42

Palmar aponeurosis

Question 43

What nerve supplies the flexor capri ulnaris ?

Answer 43

The ulnar nerve C7,8 NOT THE MEDIAL NERVE

Question 44

State the contents of the intermediate layer of the anterior forearm

Answer 44

One muscle : - Flexor digitorum superficialis - C7,8, T1

Question 45

Where does the flexor digitorum superficialis insert ?

Answer 45

Middle phalanges (of the 4 digits) insertion

Question 46

State the insertions of the flexor carpi ulnaris/radialis

Answer 46

Inserts into the wrist

Question 47

State the contents of the deep layer of the anterior forearm

Answer 47

3 muscles - Flexor digitorum profundus - Flexor policis longus - Pronator quadratus

Question 48

Describe the innervation of flexor digitorum profundus

Answer 48

Medial 1/2 - Ulnar nerve (C8 and T1) : mainly T1 Lateral 1/2 - Anterior interosseous nerve (C8 and T1) : mainly C8

Question 49

State the insertion of the flexor digitorum profundus

Answer 49

Distal phalanges insertion

Question 50

Describe the innervation of the flexor policis longus

Answer 50

Anterior interosseous nerve (C8 and T1)

Question 51

Describe the innervation of the pronator quadratus

Answer 51

Anterior interosseous nerve (C8 and T1)

Question 52

What is the anterior interosseous nerve ?

Answer 52

A branch of the medial nerve

Question 53

Pollex meaning

Answer 53

Thumb

Question 54

Describe the position of the radial artery

Answer 54

Passes laterally, running alongside the superficial branch of the radial nerve

Question 55

Describe the position of the ulnar artery

Answer 55

Runs alongside the ulnar nerve, and these structures run deep to the flexor carpi ulnaris

Question 56

How can we get neurovascular structures and tendons into the hand ?

Answer 56

The carpal arch which is closed over by flexor retinaculum.

Question 57

What is the flexor retuinaculum ?

Answer 57

A tendinous/ligamentous connective tissue sheath running across the top of the carpal arch creating a tunnel.

Question 58

State the contents of the carpal tunnel

Answer 58

Flexor digitorum superificialis Flexor digitorum profundus Flexor policis longus Median nerve

Question 59

Describe the innervation of the dorsal (posterior) forearm

Answer 59

Radial nerve or its branches

Question 60

Movements of the dorsal (posterior) forearm

Answer 60

Extensors and Supinators

Question 61

State the groups of the dorsal (posterior) forearm

Answer 61

Superficial Outcropping Deep

Question 62

State the origin of the dorsal (posterior) forearm muscles

Answer 62

Common extensor origin - Lateral epicondyle of the humerus

Question 63

State the muscle found in the superficial group of the dorsal (posterior forearm)

Answer 63

Brachioradialis - Elbow flexor (synergist) - 1/2 pronator - 1/2 supinator

Question 64

Where does the brachioradialis insert ?

Answer 64

Inserts into the distal radius

Question 65

State the reflex associated with the brachioradialis

Answer 65

"Supinator reflex" Elicits a flexion jerk

Question 66

Function of the "supinator" reflex

Answer 66

Tests C5 and C6 spinal segments (mainly C6)

Question 67

What is the supinator reflex muscle ?

Answer 67

Brachioradialis

Question 68

State the superificial group of extensor muscles in the forearm

Answer 68

Extensor carpi radialis longus - C7 radial nerve Extensor carpi radialis brevis - C7 deep RN Extensor digitorum - C7 deep RN Extensor digiti minimi - C7 deep RN Extensor carpi ulnaris - C7 deep RN

Question 69

State the outcropping muscles of the dorsal (posterior forearm)

Answer 69

Abductor policis longus Extensor policis brevis Extensor policis longus Anatomical snuff box

Question 70

What nerve innervates the outcropping muscles ?

Answer 70

The posterior interosseous nerve C7 and 8 (mainly C8)

Question 71

Describe the anatomical snuffbox

Answer 71

Crossed by the cephalic vein, dorsal branch of the radial nerve Contains the radial artery

Question 72

Describe the floor of the anatomical snuff box

Answer 72

Scaphoid and Trapezium

Question 73

How is the anatomical snuffbox formed ?

Answer 73

Gap between the extensor policis longus and extensor policis brevis

Question 74

State the deep muscles of the dorsal (posterior forearm)

Answer 74

Supinator - deep radial nerve C7,8 (mainly 8) Extensor indicis - post. interosseous nerve (mainly C7)