Hand Muscles

Question 1

Abductor pollicis brevis origin

Answer 1

Flexor retinaculum, scaphoid, and trapezium

Question 2

Abductor pollicis brevis insertion

Answer 2

Radial side of proximal phalanx of thumb

Question 3

Abductor pollicis brevis innervation and spinal level

Answer 3

Median C8, T1

Question 4

Abductor pollicis brevis action

Answer 4

Abduct thumb, assist flexion at MCP joint

Question 5

Flexor pollicis brevis origin

Answer 5

Flexor retinaculum, trapezium, and capitate

Question 6

Flexor pollicis brevis insertion

Answer 6

Base of palmar surface of proximal phalanx of thumb

Question 7

Flexor pollicis brevis innervation and spinal level

Answer 7

Median C8,T1

Question 8

Flexor pollicis brevis action

Answer 8

Flexes MCP & CMC joint ; assist opposition and adduction of thumb

Question 9

Opponens pollicis origin

Answer 9

Flexor retinaculum and trapezium

Question 10

Opponens pollicis insertion

Answer 10

The whole length of the radial side of palmar surface of first metacarpal

Question 11

Opponens pollicis innervation and spinal level

Answer 11

Median C8 T1

Question 12

Opponens pollicis action

Answer 12

Opposition of the thumb

Question 13

Adductor pollicis origin

Answer 13

Transverse head: palmar surface of the body of the 3rd metacarpal
Oblique head: palmar surface of the bases of 2nd and 3rd metacarpals and capitate (sometimes trapezoid and trapezium)

Question 14

Adductor pollicis insertion

Answer 14

Ulnar Side of palmar surface of base of proximal phalanx of thumb

Question 15

Adductor pollicis innervation and spinal level

Answer 15

Deep branch of ulnar C8 T1

Question 16

Adductor pollicis action

Answer 16

adduct thumb (1st metacarpal) ; assists flexion at carpometacarpal joint, assists in opposition; weak flexor at MCP

Question 17

Abductor digiti minimi origin

Answer 17

Pisiform bone

Question 18

Abductor digiti minimi insertion

Answer 18

Ulnar surface of base of proximal phalanx of little finger, extensor hood

Question 19

Abductor digiti minimi innervation and spinal level

Answer 19

Deep branch of ulnar C8 T 1

Question 20

Abductor digiti minimi action

Answer 20

Abduct little finger at MCP joint; assist flexion at MCP ; weak IP extensor

Question 21

Flexor digiti minimi brevis origin

Answer 21

Hook of hamate and flexor retinaculum

Question 22

Flexor digit minimi brevis insertion

Answer 22

Ulnarly and slightly palmarly on the proximal phalanx of little finger

Question 23

Flexor digit minimi innervation and spinal level

Answer 23

Deep branch of ulnar C8 T1

Question 24

Flexor digit minimi brevis action

Answer 24

Flex little finger (proximal phalanx at MCP)

Question 25

Opponens digit minimi origin

Answer 25

Hook of hamate and flexor retinaculum

Question 26

Opponens digit minimi insertion

Answer 26

Ulnar border of shaft of 5th metacarpal

Question 27

Opponens digit minimi innervation and spinal level

Answer 27

Deep branch of ulnar C8 T1

Question 28

Opponens digit minimi action

Answer 28

Draws little finger anteriorly (out of palm) and rotates it radially, bringing it into opposition with thumb and deepening the hollow of the hand

Question 29

Lumbricals origin

Answer 29

1st and 2nd: radial sides of flexor digitorum tendons to index and middle finger respectively 3rd and 4th : adjacent sides of FDP tendons to middle and ring, and ring and little fingers respectively

Question 30

Lumbricals insertion

Answer 30

Radial sides of extensor aponeurosis (dorsal hood) of fingers 2-5

Question 31

Lumbricals innervation and spinal level

Answer 31

1st and 2nd: median C8 T1 | 3rd and 4th: deep branch of ulnar C8 T1

Question 32

Lumbricals action

Answer 32

Flex at MCP joints, extend at IP joints

Question 33

Dorsal interossei origin

Answer 33

Adjacent surface of 1st/2nd, 2nd/3rd, 3rd/4th, and 4th/5th metacarpals

Question 34

Dorsal interossei insertion

Answer 34

1st: radial side of base of proximal phalanx of 2nd digit and dorsal hood 2nd: radial side of base of proximal phalanx of 3rd digit and dorsal hood 3rd: ulnar side of base of proximal phalanx of 3rd digit and dorsal hood 4th: ulnar side of base of proximal phalanx of 4th digit and dorsal hood

Question 35

Dorsal interossei innervation and spinal level

Answer 35

Deep branch of ulnar C8 T1

Question 36

Dorsal interossei action

Answer 36

Abduct 2nd, 3rd, 4th digits; assist MCP flexion and IP extension

Question 37

Palmar interossei origin

Answer 37

1st: ulnar side of 2nd metacarpal 2nd: radial side of 4th metacarpal 3rd: radial side of 5th metacarpal

Question 38

Palmar interossei insertion

Answer 38

1st: ulnar side of proximal phalanx of 2nd digit and dorsal hood 2nd: radial side of proximal phalanx of 4th digit and dorsal hood 3rd: radial side of proximal phalanx of 5th digit and dorsal hood

Question 39

Palmar interossei innnervation and spinal level

Answer 39

Deep branch of ulnar C8 T1

Question 40

Palmar interossei action

Answer 40

Adduct 2nd, 4th, and 5th digits; assist MCP flexion and IP extension