Hand Muscles

Question 1

Abductor Pollicis Brevis

Answer 1

O: Flexor Retinaculum, Trapezium, Scaphoid

I: Base of Proximal Phalanx of thumb

N: Median (C6-T1)

A: Abduct Thumb, assist w/ opposition

Question 2

Flexor Pollicis Brevis

Answer 2

O: Flexor Retinaculum, Trapezium, Trapezoid, Capitate

I: Base of Proximal Phalanx of thumb

N: Median (C6-T1); Ulnar (C8-T1)

A: Flex thumb, assist w/ opposition of thumb

Question 3

Opponens Pollicis

Answer 3

O: Flexor Retinaculum, Trapezium

I: 1st Metacarpal bone

N: Median (C6-T1)

A: Opposition of thumb

Question 4

Adductor Pollicis

Answer 4

O: Capitate, 2nd/3rd metacarpals

I: Base of proximal phalanx of thumb

N: Ulnar (C8-T1)

A: Adduct thumb, assist w/ flexion of thumb

Question 5

Abductor Digiti Minimi

Answer 5

O: Pisiform tendon of Flexor Carpi Ulnaris

I: Base of proximal phalanx of 5th digit (ulnar side)

N: Deep branch of Ulnar nerve (C7-T1)

A: Abduct 5th digit, assist w/ opposition of 5th digit

Question 6

Flexor Digiti Minimi Brevis

Answer 6

O: Hook of hamate, flexor retinaculum

I: Base of proximal phalanx of 5th digit (palmar side)

N: Deep branch of Ulnar nerve (C7-T1)

A: Flex proximal phalanx of 5th digit, assist w/ opposition of 5th digit

Question 7

Opponens Digiti Minimi

Answer 7

O: Hook of hamate and flexor retinaculum

I: Shaft of 5th metacarpal (ulnar side)

N: Deep branch of Ulnar nerve (C7-T1)

A: Opposition of 5th digit

Question 8

Lumbricals 1/2

Answer 8

O: Lateral two tendons of flexor digitorum profundus

I: Extensor expansions of digits 2 and 3 (Lateral sides)

N: Median nerve (C8-T1)

A: Flex digits at 2-3 joints and extend 2-3 IP joints

Question 9

Lumbricals 3/4

Answer 9

O: Medial 3 tendons of flexor digitorum profundus

I: Extensor expansion digits 4 and 5 (lateral sides)

N: Deep branch of Ulnar nerve (C8-T1)

A: Flex digits at 4-5 joints and extend 4-5 IP joints

Question 10

Dorsal Interossei 1-4

Answer 10

O: Adjacent sides of all metacarpals

I: Extensor expansions and bases of proximal phalanges of digits 2-4

N: Deep branch of Ulnar nerve (C8-T1)

A: Abduct 2-4 digits, assist w/ flexion of 2-4 digits, assist w/ extension of 2-4 digits

Question 11

Palmar Interossei 1-3

Answer 11

O: Base of 1, 2, 4, 5 Metacarpals

I: Extensor expansions of digits and bases of proximal phalanges of digits 2, 4, 5

N: Deep branch of Ulnar nerve (C8-T1)

A: Adduct digits 1, 2, 4, 5 toward 3rd digit; assist w/ flexions of 1, 2 , 4, 5 at MCP; Assist w/ extension of 1, 2, 4, 5 at MCP