Thenar muscles of hand

Question 1

What are the thenar muscles?

Answer 1

Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis - Superficial head
Deep head
Abductor pollicis - Oblique head
Transverse head

Question 2

What is the proximal attachment of the opponens pollicis?

Answer 2

Flexor retinaculum and tubercles of scaphoid and trapezium

Question 3

What is the distal attachment of the opponens pollicis?

Answer 3

Lateral side of 1st metacarpal

Question 4

What is the innervation of the opponens pollicis?

Answer 4

Recurrent branch of median nerve (C8, T1)

Question 5

What is the main action of the opponens pollicis?

Answer 5

To oppose thumb, it draws 1st metacarpal medially to the centre of palm and rotates it medially

Question 6

What is the proximal attachment of the abductor pollicis brevis?

Answer 6

Flexor retinaculum and tubercles of scaphoid and trapezium

Question 7

What is the distal attachment of the abductor pollicis brevis?

Answer 7

Lateral side of base of proximal phalanx of thumb

Question 8

What is the innervation of the abductor pollicis brevis?

Answer 8

Recurrent branch of median nerve (C8, T1)

Question 9

What is the main action of the abductor pollicis brevis?

Answer 9

Abducts thumb; helps oppose it

Question 10

What is the proximal attachment of the superficial head of the flexor pollicis brevis?

Answer 10

Flexor retinaculum and tubercles of scaphoid and trapezium

Question 11

What is the distal attachment of the superficial head of the flexor pollicis brevis?

Answer 11

Lateral side of base of proximal phalanx of thumb

Question 12

What is the innervation of the superficial head of the flexor pollicis brevis?

Answer 12

Recurrent branch of median nerve (C8, T1)

Question 13

What is the main action of the superficial head of the flexor pollicis brevis?

Answer 13

Flexes thumb

Question 14

What is the proximal attachment of the deep head of the flexor pollicis brevis?

Answer 14

Flexor retinaculum and tubercles of scaphoid and trapezium

Question 15

What is the distal attachment of the deep head of the flexor pollicis brevis?

Answer 15

Lateral side of base of proximal phalanx of thumb

Question 16

What is the innervation of the deep head of the flexor pollicis brevis?

Answer 16

Deep branch of ulnar nerve (C8, T1)

Question 17

What is the main action of the deep head of the flexor pollicis brevis?

Answer 17

Flexes thumb

Question 18

What is the proximal attachment of the oblique head of the adductor pollicis?

Answer 18

Bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals

Question 19

What is the distal attachment of the oblique head of the adductor pollicis?

Answer 19

Medial side of base of proximal phalanx of thumb

Question 20

What is the innervation of the oblique head of the adductor pollicis?

Answer 20

Deep branch of ulnar nerve (C8, T1)

Question 21

What is the main action of the oblique head of the adductor pollicis?

Answer 21

Adducts thumb towards lateral border of palm

Question 22

What is the proximal attachment of the transverse head of the adductor pollicis?

Answer 22

Anterior surface of shaft of 3rd metacarpal

Question 23

What is the distal attachment of the transverse head of the adductor pollicis?

Answer 23

Medial side of base of proximal phalanx of thumb

Question 24

What is the innervation of the transverse head of the adductor pollicis?

Answer 24

Deep branch of ulnar nerve (C8, T1)

Question 25

What is the main action of the transverse head of the adductor pollicis?

Answer 25

Adducts thumb towards lateral border of palm