Muscles of the Arm

Question 1

What is the anatomical arm?

Answer 1

The shoulder joint to the elbow joint

Question 2

What muscles are in the anterior arm?

Answer 2

Biceps brachii
Brachialis
Coracobrachialis

Question 3

What muscles are in the posterior arm?

Answer 3

Triceps

Anconeus

Question 4

What are muscles in the anterior compartment of the arm innervated by?

Answer 4

The musclocutaneous nerve

Question 5

What kind of muscle is the biceps brachii?

Answer 5

Two headed

Question 6

Where is nearly all the muscle mass of the biceps located?

Answer 6

Anterior to the humerus

Question 7

Does the biceps have an attachment to the humerus?

Answer 7

No

Question 8

What is the proximal attachment of the long head of the biceps brachii?

Answer 8

Supraglenoid tubercle of the scapula

Question 9

What is the proximal attachment of the short head of the biceps brachii?

Answer 9

Tip of coracoid process of scapula

Question 10

How is the muscle belly of the biceps brachii formed?

Answer 10

By the combination of the two heads

Question 11

Where do the two heads of the biceps brachii combine?

Answer 11

At the level of the humeral shaft

Question 12

How do the two heads of the biceps brachii combine?

Answer 12

The tendon of the long head passes through the shoulder joint and intertubercular groove of the humerus to meet the short head

Question 13

What is the distal attachment of the biceps brachii?

Answer 13

Tuberosity of the radius and fascia of the forearm, via bicipital aponeurosis

Question 14

What is the biceps brachii innervated by?

Answer 14

Musculocutaneous nerve (C5-7)

Question 15

What does a tap on the biceps tendon test?

Answer 15

Spinal cord segment C6

Question 16

What is the arterial supply of the biceps brachii?

Answer 16

Brachial artery

Question 17

What is the action of the biceps brachii?

Answer 17

Supinates forearm, and when it is supine, flexes forearm

Short head resists dislocation of the shoulder

Question 18

What happens as the biceps tendon enters the forearm?

Answer 18

A connective tissue sheet is given off, called the bicipital aponeurosis

Question 19

What does the bicipital aponeurosis form?

Answer 19

The roof of the cubital fossa

Question 20

What does the bicipital aponeurosis blend with?

Answer 20

The deep fascia of the anterior forearm

Question 21

How common is a complete rupture of a body tendon?

Answer 21

Rare

Question 22

What is one of more common tendons to rupture?

Answer 22

The long head of the biceps tendon

Question 23

What does the rupture of the biceps tendon produce?

Answer 23

A characteristic bulge where the muscle belly is on flexing at the elbow, called the ‘Popeye Sign ‘

Question 24

Would a patient with a rupture of the biceps tendon notice much weakness in the upper limb?

Answer 24

No, due to the action of the brachialis and supinator muscles

Question 25

Where does the coracobrachialis muscle lie?

Answer 25

Deep to the biceps brachii in the arm

Question 26

Where is the proximal attachment of the coracobrachialis?

Answer 26

Tip of the coracoid process of scapula

Question 27

Where does the coracobrachialis pass?

Answer 27

Through the axilla

Question 28

Where is the distal attachment of the coracobrachialis?

Answer 28

Middle third of the medial surface of the humerus, at the level of the deltoid tubercle

Question 29

What is the innervation of the coracobrachialis?

Answer 29

Musculocutaneous nerve (C5, C6, C7)

Question 30

What is the arterial supply of the coracobrachialis?

Answer 30

Brachial artery

Question 31

What is the function of the coracobrachialis?

Answer 31

Helps flex and adduct the arm  | Resists dislocation of the shoulder

Question 32

Where does the brachialis muscle lie?

Answer 32

Deep to the biceps brachii, more distally than the other muscles of the arm

Question 33

What does the brachialis form?

Answer 33

The base of the cubital fossa

Question 34

What is the proximal attachment of the brachialis?

Answer 34

Distal half of anterior surface of humerus

Question 35

What is the distal attachment of the brachialis?

Answer 35

Coronoid process | Tuberosity of ulna

Question 36

What is the innervation of the brachialis?

Answer 36

``` Musculocutaneous nerve (C5, C6) Small lateral portion by radial nerve (C5, C7) ```

Question 37

What is the arterial supply of the brachialis?

Answer 37

Brachial artery | Radial recurrent artery

Question 38

What is the action of the brachialis?

Answer 38

Flexes forearm in all positions

Question 39

What does the triceps brachii have?

Answer 39

Three heads

Question 40

Where does the medial head of the triceps lie?

Answer 40

Deeper than the other two

Question 41

When is the medial head visible?

Answer 41

When the other two heads have been dissected away

Question 42

What is the proximal attachment of the long head of the triceps?

Answer 42

Infraglenoid tubercle of the scapula

Question 43

What is the proximal attachment of the lateral head of the triceps brachii?

Answer 43

Posterior surface of the humerus, superior to radial groove

Question 44

What is the proximal attachment of the medial head of the triceps brachii?

Answer 44

Posterior surface of the humerus, inferior to the radius groove

Question 45

What happens to the three heads of the triceps brachii?

Answer 45

They combine to make one muscle and converge to a tendon

Question 46

What is the distal attachment of the triceps brachii?

Answer 46

Proximal end of the olcranon of ulna | Fascia of forearm

Question 47

What is the innervation of the triceps brachii?

Answer 47

Radial nerve (C6-8)

Question 48

What is the arterial supply of the triceps brachii?

Answer 48

Deep brachial artery

Question 49

What is the action of the triceps brachii?

Answer 49

Chief extensor of forearm  Long head resists dislocation of humerus  Especially important during adduction

Question 50

What does a tap on the triceps tendon test?

Answer 50

Spinal segment C7

Question 51

What is the proximal attachment of the anconeus?

Answer 51

Lateral epicondyle of humerus

Question 52

What is the distal attachment of the anconeus?

Answer 52

Lateral surface of olecranon and superior part of posterior surface of ulna

Question 53

What is the innervation of the anconeus?

Answer 53

Radial nerve (C7, C8, T1)

Question 54

What is the arterial supply of the anconeus?

Answer 54

Recurrent interosseous artery

Question 55

What is the action of the anconeus?

Answer 55

Assists triceps in extending the forearm  Stabilises elbow joint  May abduct ulna during pronation