Question 1

Which are the attachments of the abductor pollicis longus?

Accepted Answer

The abductor pollicis longus muscle attaches to the posterior radius and ulna (bones of the forearm) and to the thumb, allowing for abduction and extension of the thumb.

Question 2

Which is an action of the flexor digitorum superficialis?

Accepted Answer

The action of the flexor digitorum superficialis is to flex the hand at the wrist joint.

Question 3

Which muscles attach onto the lateral epicondyle of the humerus (via the common extensor tendon)?

Accepted Answer

The extensor digitorum and extensor digiti minimi muscles attach onto the lateral epicondyle of the humerus via the common extensor tendon. Option A and D mention the flexor muscles which do not attach to the lateral epicondyle. Option B mentions both flexor and extensor muscles, but only the extensor muscles attach to the lateral epicondyle.

Question 4

Which are the attachments of the flexor digitorum superficialis?

Accepted Answer

The flexor digitorum superficialis attaches to the medial epicondyle of the humerus via the common flexor tendon and to the anterior ulna and radius, and then continues to attach to the anterior surfaces of fingers two through five.

Question 5

Which is an action of the flexor digitorum profundus?

Accepted Answer

The flexor digitorum profundus is a forearm muscle that inserts into the distal phalanges of the fingers two through five. Its action is to flex these fingers at the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints. Therefore, the best choice is D.

Question 6

Which is an action of the flexor digitorum profundus?

Accepted Answer

The flexor digitorum profundus is primarily responsible for flexing the fingers, particularly at the distal interphalangeal joints, which contributes to the overall action of flexing the hand at the wrist joint.

Question 7

Which are the attachments of the extensor pollicis longus?

Accepted Answer

The extensor pollicis longus muscle originates from the posterior surface of the ulna and the interosseous membrane, and inserts into the base of the distal phalanx of the thumb. This makes option A correct, as it accurately describes the attachment from the posterior ulna to the thumb.

Question 8

Which are the attachments of the extensor pollicis brevis?

Accepted Answer

The extensor pollicis brevis muscle originates from the posterior surface of the radius and the interosseous membrane, and it inserts into the base of the proximal phalanx of the thumb, thus extending from the posterior radius to the thumb.

Question 9

Which are the attachments of the flexor digitorum profundus?

Accepted Answer

The flexor digitorum profundus originates from the medial and anterior ulna and attaches to the anterior surfaces of fingers two through five. The other options are incorrect because they refer to different bones and surfaces of the body.

Question 10

Which are the attachments of the flexor pollicis longus?

Accepted Answer

The flexor pollicis longus muscle attaches to the anterior surface of the radius and to the thumb. None of the other attachments listed are correct for this muscle.

Question 11

Which is an action of the flexor pollicis longus?

Accepted Answer

The flexor pollicis longus muscle is responsible for flexion of the thumb at the carpometacarpal, metacarpophalangeal, and interphalangeal joints. It does not have any action on the forearm or arm at the elbow or glenohumeral joint, so options A, C, and D are incorrect.

Question 12

Which are the attachments of the extensor indicis?

Accepted Answer

The extensor indicis attaches from the posterior ulna to the index finger (finger number two).

Question 13

Which is an action of the flexor pollicis longus?

Accepted Answer

The action of the flexor pollicis longus is to flex the thumb at the interphalangeal joint and also to flex the hand at the wrist joint. Therefore, option C, which describes flexion of the hand at the wrist joint, is the correct answer. Options A, B, and D all describe actions of other muscles, and are not related to the flexor pollicis longus.

Question 14

Which are the attachments of the extensor digiti minimi?

Accepted Answer

The extensor digiti minimi attaches to the lateral epicondyle of the humerus via the common extensor tendon and to the phalanx of the little finger (finger number five).

Question 15

If a muscle crosses the metacarpophalangeal and interphalangeal joints of fingers two through five on the dorsal (posterior)side with a vertical orientation to its fibers,what will its action most likely be?

Accepted Answer

A muscle with vertical fibers crossing the dorsal side of the metacarpophalangeal and interphalangeal joints of fingers two through five would most likely be the extensor muscle of the fingers, causing extension of the joints when contracted.

Question 16

Which are the attachments of the extensor digitorum?

Accepted Answer

The extensor digitorum muscle attaches to the lateral epicondyle of the humerus via the common extensor tendon and goes all the way down to the phalanges of fingers two through five.

Question 17

Which is an action of the flexor digitorum superficialis?

Accepted Answer

The flexor digitorum superficialis is responsible for flexion of the fingers two through five at the metacarpophalangeal and proximal interphalangeal joints.

Question 18

If a muscle crosses the metacarpophalangeal and interphalangeal joints of fingers two through five on the palmar (anterior)side with a vertical orientation to its fibers,what will its action most likely be?

Accepted Answer

A muscle that crosses the metacarpophalangeal and interphalangeal joints of fingers two through five on the palmar (anterior) side with a vertical orientation to its fibers is most likely to be a flexor muscle. Flexor muscles are responsible for bending the fingers at these joints.

Question 19

Which muscles attach onto the thumb?

Accepted Answer

The abductor pollicis longus and extensor pollicis brevis both attach onto the thumb. The other muscle pairs listed do not attach directly to the thumb.

Question 20

Which is an action of the extensor digitorum?

Accepted Answer

The extensor digitorum muscle is responsible for extending (straightening) fingers two through five at the metacarpophalangeal, proximal, and distal interphalangeal joints.

Quiz 8: Extrinsic Muscles of the Finger Joints

Which are the attachments of the abductor pollicis longus?

Which is an action of the flexor digitorum superficialis?

Which muscles attach onto the lateral epicondyle of the humerus (via the common extensor tendon) ?

Which are the attachments of the flexor digitorum superficialis?

Which is an action of the flexor digitorum profundus?

Which is an action of the flexor digitorum profundus?

Which are the attachments of the extensor pollicis longus?

Which are the attachments of the extensor pollicis brevis?

Which are the attachments of the flexor digitorum profundus?

Which are the attachments of the flexor pollicis longus?

Which is an action of the flexor pollicis longus?

Which are the attachments of the extensor indicis?

Which is an action of the flexor pollicis longus?

Which are the attachments of the extensor digiti minimi?

If a muscle crosses the metacarpophalangeal and interphalangeal joints of fingers two through five on the dorsal (posterior) side with a vertical orientation to its fibers,what will its action most likely be?

Which are the attachments of the extensor digitorum?

Which is an action of the flexor digitorum superficialis?

If a muscle crosses the metacarpophalangeal and interphalangeal joints of fingers two through five on the palmar (anterior) side with a vertical orientation to its fibers,what will its action most likely be?

Which muscles attach onto the thumb?

Which is an action of the extensor digitorum?