Arm muscles (Quiz 1)

Question 1

What are the 3 flexor muscles in the anterior compartment?

Answer 1

1) biceps brachii
2) brachialis
3) coracobrachialis

Question 2

What nerve supplies the anterior flexor compartment of the arm?

Answer 2

musculocutaneous n.

Question 3

What is the extensor muscle in the posterior compartment?

Answer 3

triceps brachii

Question 4

What nerve supplies the posterior extensor compartment of the arm?

Answer 4

radial n.

Question 5

A distally placed assistant to the triceps, the ___________, also lies in the posterior compartment

Answer 5

anconeus

Question 6

The flexor muscles of the anterior compartment are almost twice as strong as the extensors in all positions; consequently, we are better _________ than __________

Answer 6

pullers, pushers

Question 7

The extensors of the elbow are particularly important for what?

Answer 7

raising oneself out of a chair and for wheelchair activity

Question 8

Conditioning of the triceps is particularly important in who?

Answer 8

elderly or disabled patients (to help them sit up from chair or be able to move around wheelchair)

Question 9

The biceps is a ___ joint muscle- at the glenohumeral, elbow, and radioulnar joints, although it primarily acts at the latter two.

Answer 9

3

Question 10

When the forearm is pronated, the biceps brachii is the primary (most powerful)…..

Answer 10

supinator of the forearm

Question 11

The long head of the biceps brachii arises from the ______________________ and descends in the ___________________________

Answer 11

supraglenoid tubercle, intertubercular groove of the humerus

Question 12

What ligament holds the tendon of the long head of the biceps in the intertubercular groove/bicipital groove?

Answer 12

transverse humeral ligament

Question 13

What is biceps tendonitis?

Answer 13

-inflammation of the biceps tendon
-usually the result of repetitive microtraumas
-common in sports involving throwing, like baseball, or using a racquet, like in tennis

Question 14

A tight, narrow and/or rough intertubercular groove may irritate and inflame the biceps tendon, producing tenderness and….

Answer 14

crepitus (crackling sound)

Question 15

Which muscle’s distal attachment covers the anterior part of the elbow joint?

Answer 15

brachialis

Question 16

What muscle is the primary flexor of the forearm in all positions?

potential test q

Answer 16

brachialis

Question 17

What muscle is regarded as the workhorse of the elbow flexors?

Answer 17

brachialis

Question 18

The ____________________ helps flex and adduct the arm and stabilizes the glenohumeral joint. It serves as a shunt muscle, resisting downward dislocation of the head of the humerus, as when carrying a heavy suitcase

Answer 18

coracobrachialis

Question 19

What muscle is the main extensor of the forearm?

Answer 19

triceps brachii

Question 20

What muscle helps stabilize the adducted glenohumeral joint by serving as a shunt muscle, resisting inferior displacement of the head of the humerus?

Answer 20

triceps brachii

Question 21

What muscle’s medial head is the workforce of forearm extension?

potential test q

Answer 21

triceps brachii

Question 22

The ______________ helps the triceps extend the forearm and tendons of the capsule of the elbow joint, preventing it being pinched during extension

Answer 22

aconeus

Question 23

What are the 5 muscles of the arm?

Answer 23

1) biceps brachii
2) coracobrachialis
3) brachialis
4) triceps brachii
5) anconeus

Question 24

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

Answer 24

tip of coracoid process of scapula (same as coracobrachialis origin)

Question 25

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

Answer 25

supraglenoid tubercle of scapula

Question 26

What is the insertion/distal attachment of the biceps brachii?

Answer 26

radial tuberosity and fascia of forearm via bicipital aponeurosis

Question 27

What innervates the biceps brachii?

Answer 27

musculocutaneous n.

Question 28

What are the actions of the biceps brachii?

Answer 28

-supinates forearm when it is prone -flexes forearm -short head resists dislocation of shoulder

Question 29

What is the origin/proximal attachment of the coracobrachialis?

Answer 29

tip of coracoid process of scapula (same as biceps brachii short head origin)

Question 30

What is the insertion/distal attachment for the coracobrachialis?

Answer 30

middle third of the medial surface of the humerus

Question 31

What innervates the coracobrachialis?

Answer 31

musculocutaneous n.

Question 32

What are the actions of the coracobrachialis?

Answer 32

-helps flex and adduct arm -resist dislocation of shoulder

Question 33

What is the origin/proximal attachment of the brachialis?

Answer 33

distal half of the anterior surface of the humerus

Question 34

What is the insertion/distal attachment of the brachialis?

Answer 34

coronoid process of the ulna and ulna tuberosity

Question 35

What innervates the brachialis?

Answer 35

musculocutaneous n. and radial n.

Question 36

What are the actions of the brachialis?

Answer 36

flexes forearm in all positions

Question 37

What is the origin/proximal attachment for the long head of the triceps brachii?

Answer 37

infraglenoid tubercle of scapula

Question 38

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

Answer 38

posterior surface of the humerus (superior to the radial groove)

Question 39

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

Answer 39

posterior surface of the humerus (inferior to radial groove)

Question 40

What is the insertion/distal attachment of the triceps brachii?

Answer 40

proximal end of the olecranon of the ulna and fascia of the forearm

Question 41

What innervates the triceps brachii?

Answer 41

radial n.

Question 42

What are the actions of the triceps brachii?

Answer 42

-chief extensor of forearm -long head resists dislocation of humerus -important for adduction -long head is the least active head -medial is the workhorse of forearm extension -lateral head is the strongest but usually for going against resistance

Question 43

Which head of the triceps is the least active head?

Answer 43

long head

Question 44

Which head of the triceps is known as the workhorse of forearm extension?

Answer 44

medial head

Question 45

Which head of the triceps is the strongest against resistance?

Answer 45

lateral head

Question 46

What is the origin/proximal attachment for the anconeus?

Answer 46

lateral epicondyle of the humerus

Question 47

What is the insertion/distal attachment of the anconeus?

Answer 47

lateral surface of the olecranon and superior part of the posterior surface of the ulna

Question 48

What innervates the anconeus?

Answer 48

radial n.

Question 49

What are the actions of the anconeus?

Answer 49

-assist triceps in extending forearm -stabilizes elbow joint -may abduct ulna during pronation