Deck 9: Structure and Function of the Elbow Complex

Question 1

Because muscles are stretched when moved in the opposite direction of their function when activated, which of the following motions to end range would stretch the long head of the triceps muscle?

A)Shoulder and elbow flexion
B)Elbow extension
C)Shoulder and elbow extension
D)Elbow flexion

Answer 1

Shoulder and elbow flexion

Question 2

Which of the following muscle(s) functions (function) as a primary supinator muscle of the forearm?

A)Supinator, triceps
B)Supinator
C)Supinator, biceps brachii
D)Biceps brachii

Answer 2

Supinator, biceps brachii

Question 3

What is the average active range of elbow flexion required for MOST functional activities?

A)30°-130°
B)0°-140°
C)30°-160°
D)0°-170°

Answer 3

30°-130°

Question 4

A person sustains a tear to the proximal attachment of the long head of the biceps.Which of the following movements are MOST LIKELY to be affected by this injury?

A)Elbow flexion, forearm pronation
B)Shoulder flexion, elbow flexion, forearm supination
C)Elbow flexion, forearm supination and pronation
D)Shoulder flexion, elbow flexion, forearm pronation

Question 5

Which of the following muscles supinates the forearm to a neutral position when it is initially positioned in full pronation?

A)Supinator
B)Biceps brachii
C)Pronator teres
D)Brachioradialis

Question 6

What type of stress does the ulnar (medial) collateral ligament counter?

A)Varus
B)Anterior
C)Valgus
D)Posterior

Question 7

A person sustains a tear to the proximal attachment of the short head of the biceps.Which of the following movements are MOST LIKELY to be affected by this injury?

A)Elbow flexion, forearm pronation
B)Shoulder flexion, elbow flexion, forearm supination
C)Elbow flexion, forearm supination
D)Shoulder flexion, elbow flexion, forearm pronation

Question 8

Which of the following bony sites serves as the proximal attachment for the supinator muscle?

A)Radial head
B)Medial humeral epicondyle
C)Radial styloid process
D)Lateral humeral epicondyle

Question 9

Which of the following structures provides stability to the radial head as it rotates around the ulna?

A)Lateral collateral ligament
B)Quadrate ligament
C)Medial collateral ligament
D)Annular ligament

Question 10

What are the arthrokinematics of the ulnar trochlear notch during open-chain elbow flexion?

A)Rolls anteriorly and glides posteriorly
B)Rolls and glides anteriorly
C)Rolls posteriorly and glides anteriorly
D)Rolls and glides posteriorly

Question 11

In which of the following elbow positions is the biceps brachii able to generate the greatest supination force?

A)90° of elbow flexion
B)0° of elbow flexion
C)30° of elbow flexion
D)130° of elbow flexion

Question 12

What is the average carrying angle of the elbow?

A)5°
B)10°
C)15°
D)20°

Question 13

What type of stress does the radial (lateral) collateral ligament counter?

A)Varus
B)Anterior
C)Valgus
D)Posterior

Question 14

Which of the following joints form the elbow complex?

A)Humeroradial, humeroulnar, and proximal radioulnar joints
B)Humeroradial and humeroulnar joints
C)Humeroradial, humeroulnar, and proximal and distal radioulnar joints
D)Proximal and distal radioulnar joints

Question 15

Which of the following elbow flexor muscle attachments can be palpated distally at the radial styloid process?

A)Long head of biceps
B)Brachialis
C)Short head of biceps
D)Brachioradialis

Question 16

What are the arthrokinematics of the ulnar trochlear notch during open-chain elbow extension?

A)Rolls anteriorly and glides posteriorly
B)Rolls and glides anteriorly
C)Rolls posteriorly and glides anteriorly
D)Rolls and glides posteriorly

Question 17

Which of the following positions of the elbow would allow the biceps brachii to produce its greatest force?

A)Full joint end-range extension
B)Between 0° and 60° of flexion
C)Full joint end-range flexion
D)Between 90° and 100° of flexion

Question 18

Which of the following positions of the elbow would allow the brachioradialis muscle to produce its greatest force?

A)Between 0° and 90° of elbow flexion with forearm in 80° of pronation
B)Between 100° and 120° of elbow flexion with forearm in 80° of pronation
C)Between 0° and 90° of elbow flexion with forearm in neutral
D)Between 100° and 120° of elbow flexion with forearm in neutral

Question 19

During forearm pronation, which of the following movements occurs?

A)Ulna pivots around radius in sagittal plane around frontal axis
B)Radius pivots around ulna in transverse plane around vertical axis
C)Radius pivots around ulna in sagittal plane around frontal axis
D)Ulna pivots around radius in transverse plane around vertical axis

Question 20

With reference to the law of parsimony, which of the following muscles would be activated during a prone push-up requiring maximal force?

A)Short head of the biceps, brachialis
B)Long, medial, and lateral heads of the triceps
C)Medial head of the triceps, anconeus
D)Long and short heads of the biceps

Question 21

What is the function of the triceps as shown in the image as the screwdriver is used to tighten a screw?

A)Supinates the forearm
B)Counters the flexion component of the biceps
C)Pronates the forearm
D)Counters the supination component of the biceps

Question 22

Which of the following nerves passes through the belly of the pronator teres and can be involved in compression injury?

A)Musculocutaneous
B)Median
C)Ulnar
D)Radial

Question 23

A person is complaining of tenderness with palpation of the medial humeral epicondyle.Which of the following muscles is MOST LIKELY to be involved?

A)Long head of the biceps
B)Pronator teres
C)Pronator quadratus
D)Supinator

Question 24

What does coupling of forearm supination with shoulder lateral rotation accomplish during functional activities?

A)Allows the hand to bring objects to the mouth
B)Allows the arms to assist with pushing up out of a chair
C)Allows the hand to perform tasks throughout 360° arc
D)Allows the arms to reach overhead for objects