Palm of Hand

Question 1

Lumbricals

Answer 1

O: 1+2: Lateral to 2tendons of FDP (unipennate)
3+4: Medial 3 tendons of FDP (bipinnate)
I: Lateral sides of extensor expansions of 2nd-5th digits
N: 1+2: Median Nerve C8, T1
3+4: Ulnar Nerve C8, T1
A: 1. Flex MCP joints
2. Extend IP joints of 2nd-5th digits

Question 2

Abductor Pollicis Brevis

Answer 2

O: 1. Flexor Retinaculum
2. Tubercles of scaphoid and trapezium
I: Lateral side of base of proximal phalanx of thumb
N: Median Nerve C8, T1
A: 1. ABduct thumb
2. Helps oppose thumb

Question 3

Opponens Pollicis

Answer 3

O: 1. Flexor Retinaculum
2. Tubercles of scaphoid and trapezium
I: Lateral side of 1st metacarpal
N: Median Nerve C8, T1
A: To oppose thumb, draws first metacarpal medially to center of palm and rotates it medially

Question 4

Flexor Pollicis Brevis

Answer 4

O: 1. Flexor Retinaculum
2. Tubercles of scaphoid and trapezium
I: Lateral side of base of proximal phalanx of thumb
N: Superficial Head: Median Nerve
Deep Head: Ulnar Nerve
A: Superficial Head: Flexes Thumb
Deep Head: Adducts thumb toward lateral border of palm

Question 5

Adductor Pollicis

Answer 5

O: Oblique Head: Bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals
Transverse Head: Anterior surface of shaft of 3rd metacarpal
I: Medial side of base of proximal phalanx of thumb
N: Ulnar Nerve
A: Adducts thumb toward lateral border of palm

Question 6

Abductor Digiti Minimi

Answer 6

O: Pisiform
I: Medial side of base of proximal phalanx of 5th digit
N: Ulnar Nerve
A: 1. Abducts 5th digit
2. Assists in flexion of its proximal phalanx

Question 7

Flexor Digiti Minimi Brevis

Answer 7

O: 1.  Hook of Hamate
     2. Flexor Retinaculum
I: Medial side of base of proximal phalanx of 5th digit
N: Ulnar Nerve
A: Flexes proximal phalanx of 5th digit

Question 8

Opponens Digiti Minimi

Answer 8

O: 1. Hook of Hamate
     2. Flexor Retinaculum
I: Medial border of 5th metacarpal
N: Ulnar Nerve
A: Draws 5th metacarpal anterior and rotates it, bringing 5th digit into opposition with thumb

Question 9

Palmar Interossei

Answer 9

O: Palmar surfaces of 2nd, 4th, and 5th metacarpals (unipennate)
I: 1. Bases of proximal phalanges
2. Extensor expansions of 2nd, 4th, and 5th digits
N: Ulnar Nerve C8, T1
A: 1. Adduct 2nd, 4th, and 5th digits toward axial line
2. Assist lumbricals in flexing MCP joints and extending IP joints
3. Extensor Expansions of 2nd-4th digits

Question 10

Dorsal Interossei

Answer 10

O: Adjacent sides of two metacarpals (bipennate)
I: 1. Bases of proximal phalanges
2. Extensor expansions of 2nd-4th digits
N: Ulnar Nerve C8, T1
A: 1. Abducts 2nd-4th digits from axial line
2. Acts with lumbricals in flexing MCP joints and extending IP joints