INTRINSIC MUSCLES OF THE FINGER JOINTS

Question 1

ABDUCTOR POLLICIS BREVIS: O&I

Answer 1

O: tubercle of the scaphoid and trapezium, and flexor retinaculum

I: radial side of the base of the proximal phalanx of the thumb and the DDE

Question 2

ABDUCTOR POLLICIS BREVIS: A&N

Answer 2

A: ABD the thumb at the CMC joint

N: median n.

Question 3

FLEXOR POLLICIS BREVIS: O&I

Answer 3

O: flexor retinaculum and trapezium

I: radial side of base of proximal phalanx

Question 4

FLEXOR POLLICIS BREVIS: A&N

Answer 4

A: flexes thumb at the CMC and MCP joints

N: median and ulnar n.

Question 5

OPPONENS POLLICIS: O&I

Answer 5

O: flexor retinaculum and tubercle of trapezium

I: anterior and lateral surface of the first MC of the thumb

Question 6

OPPONENS POLLICIS: A&N

Answer 6

A: opposed the thumb at the CMC joint

N: median and ulnar n.

Question 7

ABDUCTOR DIGITI MINIMI MANUS: O&I

Answer 7

O: pisiform and tendon of the flexor carpi ulnaris

I: ulnar side of the base of the proximal phalanx of finger 5 and the DDE

Question 8

ABDUCTOR DIGITI MINIMI MANUS: A&N

Answer 8

A: ABD finger 5 at the MCP and CMC joint

N: ulnar n.

Question 9

FLEXOR DIGITI MINIMI MANUS: O&I

Answer 9

O: flexor retinaculum and hook of hamate

I: anteromedial side of the base of the proximal phalanx of finger 5

Question 10

FLEXOR DIGITI MINIMI MANUS: A&N

Answer 10

A: flexes finger 5 at the MCP and CMC joint

N: ulnar n.

Question 11

OPPONENS DIGITI MINIMI: O&I

Answer 11

O: flexor retinaculum and hook of hamate

I: anterior surface of the medial border fo 5th MC

Question 12

OPPONENS DIGITI MINIMI: A&N

Answer 12

A: opposes finger 5 at the CMC joint

N: ulnar n.

Question 13

ADDUCTOR POLLICIS: O&I

Answer 13

O: anterior base of second and third MC and capitate (OH); distal 2/3 of anterior surface of third MC (TH)

I: medial side of the base of the proximal phalanx of thumb and DDE (OH); and the medial side of the base of the prox phalanx of thumb (TH)

Question 14

ADDUCTOR POLLICIS: A&N

Answer 14

A: ADD thumb at CMC joint, flexes thumb at CMC and MCP and extends thumb at IP joints

N: ulnar n.

Question 15

LUMBRICAL MANUS: O

Answer 15

O: distal tendons of FDP mm

• L1: radial side of FDP tendon of finger 2
• L2: radial side of FDP tendon of finger 3
• L3: ulnar side of FDP tendon of finger 3 AND radial side of FDP tendon of finger 4
• L4: ulnar side of FDP tendon of finger 5

Question 16

LUMBRICAL MANUS: I

Answer 16

I: radial side of the distal tendon of extensor digitorum (DDE)

• L1: into the tendon of finger 2
• L2: into the tendon of finger 3
• L3: into the tendon of finger 4
• L4: into the tendon of finger 5

Question 17

LUMBRICAL MANUS: A&N

Answer 17

A: extends fingers 2-5 at PIP and DIP joint; flexes fingers 2-5 at MCP joint

N: median and ulnar n.

Question 18

PALMAR INTEROSSEI: O

Answer 18

O: ant side and “middle finger side” of MC’s fingers 2,4 and 5
P1: attaches to MC of finger 2
P2: attaches to MC of finger 4
P3: attaches to MC of finger 5

Question 19

PALMAR INTEROSSEI: I

Answer 19

I: base of prox phalanges of fingers 2, 4 and 5 on “middle finger side” and DDE
P1: attaches to finger 2
P2: attaches to finger 4
P3: attaches to finger 5

Question 20

PALMAR INTEROSSEI: A&N

Answer 20

A: ADD and flex finger 2,4,a and 5 at MCP joint

N: ulnar n.

Question 21

DORSAL INTEROSSEI MANUS: O

Answer 21

O: MC of finger 1-5
D1: MCs of finger 1-2
D2: MC of finger 2-3
D3: MC of finger 3-4
D4: MC of finger 4-5

Question 22

DORSAL INTEROSSEI MANUS: I

Answer 22

I: base of prox phalanx of fingers 2-4 on side that faces away from center of finger 3 and DDE
D1: lateral side of finger 2
D2: lateral side of finger 3
D3: medial side of finger 3
D4: medial side of finger 4

Question 23

DORSAL INTEROSSEI MANUS: A&N

Answer 23

A: ABD and flexes finger 2-4 at MCP joint

N: ulnar n.

Question 24

PALMARIS BREVIS: O&I

Answer 24

O: flexor retinaculum and palmar aponeurosis

I: dermis of medial (ulnar) board of hand

Question 25

PALMARIS BREVIS: A&N

Answer 25

A: wrinkles skin of palm

N: ulnar n.