Hand muscles

Question 1

Extensor pollicis brevis

Answer 1

O: 
- radius
- interosseous membrane
I: base of proximal phalanx of thumb
N: posterior interosseous N (C7, C8)
F: extends MCP and CMC joint of the thumb

Question 2

Opponens pollicis

Answer 2

O: 
- trapezium
- flexor retinaculum 
I: 1st MC (radial border)
N: Recurrent branch of median N (C8, T1)
F: Medially rotates thumb

Question 3

ABDuctor pollicis brevis

Answer 3

O: 
- trapezium
- flexor retinaculum
- scaphoid  
I:
- proximal phalanx
- extensor hood of thumb
N: Recurrent branch of median N ( C8, T1)
F: ABD thumb at MCP joint

Question 4

Flexor pollicis brevis

Answer 4

O: 
- trapezium
- flexor retinaculum 
I: proximal phalanx of thumb
N: Recurrent branch of median N (C8, T1)
F: flexed thumb at MCP joint

Question 5

ADDuctor pollicis

Answer 5

O:
- transverse head: MC III
- Oblique head: capitate and bases of MC II & III
I: base of proximal phalanx and extensor hood of thumb
N: Deep branch of ulnar N (C8, T1)
F: ADD thumb

Question 6

ABDuctor digiti minimi

Answer 6

O: pisiform
I: proximal phalanx of little finger
N: Deep branch of ulnar N (C8 T1)
F: ABD 5th digit at MCP joint

Question 7

Flexor digiti minimi brevis

Answer 7

O: 
- hook of hamate
- flexor retinaculum 
I: proximal phalanx of little finger
N: Deep branch of ulnar N (C8, T1)
F: laterally rotates MC V

Question 8

Opponens digiti minimi

Answer 8

O: 
- hook of hamate
- flexor retinaculum 
I: 5th MC
N: Deep branch of ulnar N (C8, T1)
F: laterally rotates MC V

Question 9

Lumbricals

Answer 9

O: tendons of flexor digitorum profundus
I: extensor hoods of digits 2-5
N:
- medial two: deep branch of ulnar N
- lateral two: digital branches of median N
F: flex MCP joints, while extending IP joints

Question 10

Dorsal interossei

Answer 10

O: adjacent sides of MC’s
I: extensor hood and base of proximal phalanges of digits 2-4
N: deep branch of ulnar N (C8,T1)
F: ABD of digits 2-4 at MCP joints

Question 11

Palmar interossei

Answer 11

O: sides of MC’s
I:
- extensor hoods of thumb, index, ring, little fingers
- proximal phalanx of thumb
N: deep branch of ulnar N (C8, T1)
F: ADD of thumb, index, ring, pinky at MCP joints