Deck 6: The Elbow and Radioulnar Joints

Question 1

Explain the mechanics of how both acute and chronic injuries occur to cause injury to the ulnar collateral ligament of the elbow.

Answer 1

Answers will vary.The ulnar collateral ligament provides medial support to prevent the elbow from abducting (not a normal movement of the elbow) when stressed in physical activity. Many contact sports, particularly sports with throwing activities, place valgus stress on the medial aspect of the joint, resulting in injury. This may be from falling on an outstretched hand or by someone falling against the lateral aspect of the upper extremity while the hand is planted on the group. Throwing a baseball, particularly pitching, and other similar overhand activities places chronic valgus stress on the medial aspect of the medial elbow and particularly the ulnar collateral ligament. The accumulation of this stress is increased even more when the flexor pronator muscle is fatigued or lacking appropriate strength and endurance.

Question 2

Which of the following statements is true about the carrying angle?

A)It is slightly greater for men compared with women.
B)It is significantly greater in the nondominant limb than in the dominant limb.
C)It plays a major role when carrying objects.
D)It permits the forearms to clear the pelvis in the swinging movements during walking.

Answer 2

It permits the forearms to clear the pelvis in the swinging movements during walking.

Question 3

In the context of radioulnar joint movements, which of the following terms refers to the internal rotary movement of the radius on the ulna that results in the hand moving from the palm-up to the palm-down position?

A)Extension
B)Flexion
C)Supination
D)Pronation

Answer 3

Pronation

Question 4

Which of the following is an anteromedial muscle?

A)The anconeus muscle
B)The pronator teres muscle
C)The supinator teres muscle
D)The triceps brachii muscle

Question 5

Which of the following is a posterior muscle?

A)The anconeus muscle
B)The biceps brachii muscle
C)The pronator quadratus muscle
D)The pronator teres muscle

Question 6

The radial nerve innervates all of the following muscles except:

A)the anconeus muscle.
B)the brachioradialis muscle.
C)the pronator teres muscle.
D)the triceps brachii muscle.

Question 7

Which of the following is the sole action of the brachialis muscle?

A)Pronation from a supinated position
B)Supination from a pronated position
C)True flexion of the elbow
D)Weak flexion of the shoulder

Question 8

The actions of the brachioradialis muscle include all of the following except:

A)flexion of the elbow.
B)pronation from a supinated position to neutral.
C)supination from a pronated position to neutral.
D)weak flexion of the shoulder joint.

Question 9

Radioulnar supination is performed by all of the following muscles except the:

A)anconeus muscle.
B)biceps brachii muscle.
C)brachioradialis muscle.
D)supinator muscle.

Question 10

The long head of the triceps brachii muscle originates from the:

A)distal two-thirds of the posterior surface of the humerus.
B)infraglenoid tubercle below the inferior lip of the glenoid fossa of the scapula.
C)supraglenoid tubercle above the superior lip of the glenoid fossa of the scapula.
D)upper half of the posterior surface of the humerus.

Question 11

The elbow includes all of the following ligaments except the:

A)annular ligament.
B)interosseus ligament.
C)radial collateral ligament.
D)ulnar collateral ligament.

Question 12

Radioulnar pronation is performed by all of the following muscles except the:

A)brachialis muscle.
B)brachioradialis muscle.
C)pronator quadratus muscle.
D)pronator teres muscle.

Question 13

The pronator teres muscle inserts on the:

A)infraglenoid tubercle below the inferior lip of the glenoid fossa of the scapula.
B)distal two-thirds of the posterior surface of the humerus.
C)middle third of the lateral surface of the radius.
D)upper half of the posterior surface of the humerus.

Question 14

The _________ muscle does not perform flexion of the elbow.

A)biceps brachii
B)brachialis
C)brachioradialis
D)pronator quadratus

Question 15

Which of the following is not an action of the brachioradialis muscle?

A)Extension of the elbow
B)Flexion of the elbow
C)Pronation of the forearm from a supinated position to neutral
D)Supination of the forearm from a pronated position to neutral

Question 16

The supinator muscle originates from the:

A)lateral epicondyle of the humerus and neighboring posterior part of the radius.
B)lateral epicondyle of the humerus and neighboring posterior part of the ulna.
C)medial epicondyle of the humerus and neighboring posterior part of the radius.
D)medial epicondyle of the humerus and neighboring posterior part of the ulna.

Question 17

Which of the following is an action of the pronator teres muscle?

A)Weak extension of the elbow
B)Weak flexion of the elbow
C)Weak pronation from a supinated position
D)Weak supination from a pronated position

Question 18

Which of the following is an action of the biceps brachii muscle?

A)Diagonal abduction of the shoulder joint during internal rotation
B)Horizontal adduction of the shoulder joint
C)Pronation of the forearm from a neutral position to full pronation
D)Pronation of the forearm from a supinated position to neutral

Question 19

The chief function of the _______ is to pull the synovial membrane of the elbow joint out of the way of the advancing olecranon process during extension of the elbow.

A)anconeus muscle
B)pronator teres muscle
C)supinator muscle
D)triceps brachii muscle

Question 20

Which of the following muscles is best stretched by using a partner to grasp the wrist and passively take the forearm into extreme supination while maintaining full elbow extension?

A)The anconeus muscle
B)The biceps brachii muscle
C)The brachialis muscle
D)The pronator teres muscle

Question 21

The anterior interosseous nerve branching from the median nerve (C6, C7) innervates the _______.

A)brachioradialis muscle
B)pronator quadratus muscle
C)supinator muscle
D)triceps brachii muscle

Question 22

Which of the following muscles is involved in both pronation and supination?

A)The biceps brachialis muscle
B)The brachialis muscle
C)The brachioradialis muscle
D)The supinator muscle

Question 23

The posterior interosseous nerve branching from the radial nerve (C6) innervates the _______.

A)biceps brachii muscle
B)brachialis muscle
C)pronator teres muscle
D)supinator muscle

Question 24

Flexion of the elbow occurs in the _______ plane of motion, and supination of the forearm occurs in the _______ plane of motion.

A)coronal; vertical
B)sagittal; frontal
C)sagittal; transverse
D)vertical; sagittal

Question 25

Tightening a screw with a screwdriver using the right hand depends significantly upon the action of the _______.

A)biceps brachialis
B)brachioradialis
C)supinator
D)triceps brachii

Question 26

The tuberosity of the radius is in its most anterior position when the radioulnar joint is in:

A)extension
B)flexion
C)pronation
D)supination

Question 27

The scapula and the clavicle serve as proximal attachments for the muscles that flex and extend the elbow.

Question 28

Supination refers to an internal rotary movement of the radius on the ulna.

Question 29

The elbow joint is a hinge-type joint that allows only internal and external rotation in the sagittal plane.

Question 30

Lateral epicondylitis is a condition that occurs less commonly than medial epicondylitis.

Question 31

The triceps brachii muscle inserts on the olecranon process of the ulna.

Question 32

As the elbow reaches full extension, the olecranon process of the ulna is received by the olecranon fossa of the humerus, and this provides increased joint stability.

Question 33

Even though both radioulnar joints are freely moveable diarthrodial joints, the joint between the shafts of the two bones is referred to as being syndesmosis.

Question 34

The lateral supracondylar ridge is an anatomical landmark located on the radius.

Question 35

The distal attachments of the radioulnar joint muscles are located on the radius.

Question 36

A movement of the forearm away from the shoulder is best described by the term "flexion."

Question 37

Elbow motions primarily involve movement between the articular surfaces of the humerus and the ulna.

Question 38

The ulna is much larger proximally than the radius.

Question 39

The olecranon process is located on the medial aspect of the ulna.

Question 40

In the anatomical position, the tuberosity of the radius is in close proximity to the lateral side of the ulna.

Question 41

The insertion of the biceps brachii muscle is on the tuberosity of the radius and bicipital aponeurosis.

Question 42

Flexion of the forearm with a barbell in the hands, known as "curling," is an excellent exercise to develop the biceps brachii muscle.

Question 43

The ulnar collateral ligament is critical to providing medial support to prevent the elbow from abducting when stressed in physical activity.

Question 44

The biceps brachii muscle originates from the coracoid process and the supraglenoid tubercle above the superior lip of the glenoid fossa.

Question 45

The insertion of the brachialis muscle is on the coracoid process of the ulna.

Question 46

Positioning the forearm in pronation decreases the effectiveness of the biceps brachii muscle. In flexing the elbow.

Question 47

The insertion of the brachioradialis muscle is on the proximal end of the radius at the styloid process.

Question 48

Medial epicondylitis is frequently referred to as "golfer's elbow."

Question 49

The pronator teres muscle originates from the distal part of the medial supracondylar ridge of the humerus and the medial side of the proximal ulna.

Question 50

The pronator teres muscle is innervated by the median nerve (C6, C7).