KIN 100 - Arm (lecture 8)

Question 1

Describe the ulna

Answer 1

• stabilizing bone in the forearm
• ulna is medial to, and longer than, the radius

Question 2

Describe the radius

Answer 2

the bone that rotates during pronation and supination

Question 3

What are the anterior compartment muscles of the arm (3)

Answer 3

1. biceps brachii
2. Brachialis
3. Coracobrachialis

Question 4

Biceps brachii

Answer 4

Proximal attachment: Long head: supraglenoid tubercle
Short head: coracoid process

Distal attachment: radial tuberosity

Innervation: Musculocutaneous nerve

Action: Forearm supination, weak elbow flexion, assist with shoulder flexion and abduction

Question 5

What are the posterior compartment muscles of the arm (2)

Answer 5

1. Triceps brachii
2. Anconeus

Question 6

Which tendon is anchored within the bicipital groove by the transverse humeral ligament

Answer 6

long head of biceps brachii

Question 7

Which tendon attaches to the coracoid process

Answer 7

short head of biceps brachii

Question 8

Do biceps brachii have any attachments to the humerus

Answer 8

no

Question 9

where does Brachialis lie

Answer 9

deep to biceps brachii

Question 10

Brachialis

Answer 10

proximal attachment: distal half of anterior surface of humerus

distal attachment: coronoid process

Innervation: Musculocutaneous nerve

Action: elbow flexion

Question 11

What do biceps brachii and brachialis have in common

Answer 11

same innervation - musculotcutaneous nerve

Question 12

Coracobrachialis

Answer 12

proximal attachment: coracoid process

distal attachment: mid shaft of humerus, medial side

Innervation: musculocutaneous nerve

Action: shoulder flexion, shoulder adduction

Question 13

Triceps brachii

Answer 13

Proximal attachment: - Long head: infraglenoid tubercle
- lateral head: Posterior surface of humerus, proximal and lateral to the radial groove
- medial head: posterior surface of humerus , distal and medial to the radial groove

Distal attachment: Olecranon process of ulna

Innervation: radial nerve

Action: elbow extension

Question 14

Anconeus

Answer 14

proximal: lateral epicondyle of humerus

distal: lateral surface of olecranon and proximal shaft of ulna

Innervation: radial nerve

Action: Tenses the elbow capsule so that it doesn’t get pinched during extension

Question 15

When does the brachial artery arise

Answer 15

When the axillary artery passes the inferior border of teres major

Question 16

Where does the profunda brachii (deep brachial artery) arise

Answer 16

arises proximally in the arm and accompanies the radial nerve in the posterior compartment

Question 17

Describe the continuation of the brachial artery

Answer 17

continues distally , traveling alongside the median nerve until it reaches the cubital fossa (anterior aspect of elbow joint)

Question 18

What are the three superficial veins

Answer 18

1. Cephalic vein
2. Basilic vein
3. Median cubital vein

Question 19

Describe the location of the cephalic vein

Answer 19

• begins on the lateral aspect of the hand and travels proximally up the lateral side of the upper limb
• located on deltopectoral triangle

Question 20

Where does the cephalic vein drain into

Answer 20

the terminal part of the axillary vein

Question 21

Describe the location of the basilic vein

Answer 21

begins on the medial aspect of the hand and travels proximally up the medial side of the upper limb

Question 22

Which vein unites with the brachial vein to form the axillary vein

Answer 22

the basilic vein

Question 23

Describe the orientation of the median cubital vein and its function

Answer 23

crosses anterior to the cubital fossa

communicates with the cephalic and basilic veins

Question 24

What are the four main nerves that passes through the arm

Answer 24

1. Musculocultaneous
2. Median
3. Ulnar
4. Radial

Question 25

Where does the musculotcutaneous nerve branch from

Answer 25

the lateral cord of the brachial plexus

Question 26

What does musculocutaneous nerve pierce through and where does it lie in between

Answer 26

• pierces coracobrachialis
• lies between muscle bellies of biceps brachii and brachialis

Question 27

What muscles does the musculocutaneous nerve supply

Answer 27

All three 3 mucles of the anterior compartment of the arm (biceps brachii, brachialis, coracobrachialis )

Question 28

What does the median nerve branch from

Answer 28

the medial and lateral cords of the brachial plexus

Question 29

What does the median nerve run alongside with

Answer 29

the brachial artery

Question 30

What arm muscles does the median nerve supply

Answer 30

no branches and supplies no muscles in the arm
- supplies most muscles of the anterior forearm and hand

Question 31

What does the ulnar nerve branch from

Answer 31

branches from the medial cord of the brachial plexus

Question 32

What arm muscles does the ulnar nerve supply

Answer 32

supplies no arm muscles

Question 33

What does the ulnar nerve pass through

Answer 33

the groove between the medial epicondyle and the olecranon process

Question 34

What nerve is responsible for the feeling of “hitting your funny bone”

Answer 34

pinching of ulnar nerve between medial epicondyle and another harder surface

Question 35

What muscles does the ulnar nerve supply

Answer 35

one and a half musles in the anterior forearm and many muscles in the hand

Question 36

Where does the radial nerve branch from

Answer 36

posterior cord of the brachial plexus

Question 37

What compartment does the radial nerve pass into and what bone does it travel through

Answer 37

• the posterior compartment of the arm with the profunda brachii artery
• travels within the radial/spiral groove of the humerus

Question 38

What muscles does the radial nerve supply

Answer 38

all muscles of the posterior compartment of the arm

Question 39

Near the lateral epicondyle, what does the radial nerve split into and describe them

Answer 39

1. Deep branch that supplies muscle (posterior forearm compartment)
2. superficial branch that supplies the skin