Hand

Question 1

How many groups can muscles of hands b classified into?

Answer 1

2 groups:
1. Intrinsic
2. Extrinsic

Question 2

What are intrinsic muscles of hand? Name them?

Answer 2

That originate and insert within the hand
These are:
1.Dorsal interossei,
2.Palmar interossei
3.Lumbricals,
4.Thenar muscles,
5.Hypothenar muscles.

Question 3

What are extrinsic muscles of hand?

Answer 3

These are located in anterior & posterior compartment of forearm

Include:
1. flexor digitorum profundus, 2. flexor digitorum superficialis, 3.flexor carpi ulnaris
4. flexor carpi radialis
5. extensor digitorum
6.extensor carpi radialis.

Question 4

What intrinsic muscles are on the thumb side?

Answer 4

Thenar muscles

Question 5

Towards the little finger are which intrinsic muscle of hand?

Answer 5

Hypothenar

Question 6

What is thenar eminence?

Answer 6

The buldge in the hand

The thenar eminence is the fleshy mass at the base of the thumb, formed by the thenar muscles.
The thenar muscles include the abductor pollicis brevis,
flexor pollicis brevis,
and opponens pollicis.

Question 7

Name the thenar muscles (short muscles of the thumb)?
What is their common origin?
What is the origin of adductor pollicis?

Answer 7

The thenar muscles include
1.Abductor pollicis brevis
2.Flexor pollicis brevis
3.Opponens pollicis (deepest)

Common origin
Flexor Retinaculum

. Adductor pollicis
Origin

(Oblique head) - 2nd & 3rd
Metacarpal bone

(Transverse head) - 3rd metacarpal bone

Question 8

What is hypothenar eminence?

Answer 8

The hypothenar eminence is the fleshy mass at the base of the little finger,
formed by the hypothenar muscles.

The hypothenar muscles include the
1.Abductor digiti minimi 2.Flexor digiti minimi ,
3.Opponens digiti minimi

Question 9

Name the hypothenar muscles (short muscles of little finger)?

Answer 9

(just replace the “pollicis” of thenar muscles with “digiti minimi”)

The hypothenar muscles include the
1.Abductor digiti minimi(proximally)
2.Flexor digiti minimi(distilly)
3.Opponens digiti minimi(deep)

Question 10

What structure is between the thenar and hypothenar muscles,
Arches over carpal bones and blends with these muscles?

Answer 10

Flexor Retinaculum

Question 11

What muscle originates on flexor retinaculum and palmar aponeurosis?

Answer 11

Palmaris brevis

Question 12

What muscle interconnects the hypothenar and thenar muscle?

Answer 12

Palmaris brevis
(Overlies hypothenar muscles)

Question 13

Insertion of palmaris brevis?

Answer 13

Inserts medially on the dermis of skin

Question 14

How many lumbricals? Origin and insertion?

Answer 14

1. 4 lumbricals

Origin
Tendon of
flexor digitorum profundus

Insertion
Extensor expansion of medial 4 fingers

Question 15

Function of lumbricals?

Answer 15

Flex the MCP joints
Extends the interphalangeal joints of the fingers

(Except THUMB!!!)

Question 16

Difference in origin of abductor pollicis brevis and abductor pollicis longus?

Answer 16

Abductor pollicis longus
Origin:
In the forearm (posterior)
(Shafts of radius and ulna)

Abductor Pollicis Brevis
Origin
In the hand
(Scaphoid,
Trapezium,
Flexor retinaculum)

Question 17

What are the superficial thenar muscles?

Answer 17

1. Abductor pollicis brevis
2. Flexor pollicis brevis

(Both lie above opponens pollicis)

Question 18

Innervation of lumbricals?

Answer 18

Median nerve
Lateral 2 (1st and 2nd)

Ulnar nerve
Medial 2 (3rd and 4th)

Question 19

Innervation of thenar mucles?

Answer 19

Median nerve supplies;

1. Abductor pollicis brevis
2. Flexor pollicis brevis
3. Opponens pollicis

Question 20

What muscles of hand are supplied by median nerve?

Answer 20

——Meat LOAF——–

Median nerve supplies:
L ateral two lumbricals (1st and 2nd)
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis

Question 21

Origin and insertion of abductor digiti minimi?

Answer 21

origin
Pisiform bone

Insertion
Base of the proximal phalanx of little finger

Question 22

Action of abductor digiti minimi?

Answer 22

Flexes and abducts the little finger at MCP

Question 23

Origin and insertion of flexor digiti minimi?

Answer 23

Origin
Flexor retinaculum

Insertion
Base of proximal phalanx of little finger

Question 24

Action of flexor digiti minimi?

Answer 24

Flexes the little finger

Question 25

Origin and insertion of opponens digiti minimi?

Answer 25

**origin** Flexor retinaculum **Insertion** Shaft of the **metacarpal bone** of little finger

Question 26

Action of opponens digiti minimi?

Answer 26

Pulls 5th metacarpal bone forward (as in cupping the palm)

Question 27

Innervation of hypothenar muscles?

Answer 27

Deep branch of **ulnar nerve**

Question 28

Origin and insertion of adductor pollicis?

Answer 28

**Origin** **Oblique head** - **2nd** & **3rd** Metacarpal bone **Transverse head** - **3rd** metacarpal bone **Insertion** Base of proximal phalanx of thumb

Question 29

Insertion of the 3 thenar muscles that originate from flexor retinaculum?

Answer 29

1.**Abductor pollicis brevis** *Insertion* Base of proximal phalanx of thumb 2.**Flexor pollicis brevis** *Insertion* Base of proximal phalanx of thumb 3.**Opponens pollicis** Shaft of the metacarpal bone of thumb

Question 30

The muscle of thumb and little finger that does not inserts into base of proximal phalanx of thumb and little finger?

Answer 30

**Opponens pollicis** Inserts to shaft of metacarpal bone of thumb **Opponens digiti minimi** Inserts to Shaft of metacarpal bone of the little finger

Question 31

The only muscle that inserts in the base of proximal phalanx of thumb but is not innervated by median nerve?

Answer 31

**Adductor pollicis** - Deep branch of **ulnar** nerve

Question 32

Origin and insertion of dorsal interossei?

Answer 32

There are 4 dorsal interossei **Origin** Contiguous sides of **all 5 metacarpal** bones **Insertion** Base of proximal phalanx of fingers Extensor expansion

Question 33

Origin and insertion of palmar interossei?

Answer 33

**origin** 1st 2nd 4th 5th metacarpal bones (not 3rd) **Insertion** Base of proximal phalanx of fingers Extensor expansion

Question 34

Action of palmar interossei? And dorsal interossei?

Answer 34

PAD and DAB **Palmar** (PAD) **adducts** the fingers towards centre of *3rd (middle)* finger **Dorsal** (DAB) **abduct** the fingers **away** from the *middle* finger.

Question 35

Innervation of palmaris brevis?

Answer 35

Superficial branch of ulnar nerve

Question 36

The only muscle that is innervated by **superficial branch** of ulnar nerve (not deep)

Answer 36

Palmaris brevis

Question 37

Which of the thenar muscles is the largest?

Answer 37

Opponens pollicis

Question 38

Which muscle forms the anteriolateral aspect of thenar eminence? Its medial aspect?

Answer 38

**anterolateral aspect** Abductor pollicis brevis **Medial aspect** Flexor pollicis brevis

Question 39

The difference in innervation of hypthenar and thenar muscles?

Answer 39

Hypothenar - ulnar nerve Thenar - median nerve

Question 40

Action of palmaris brevis?

Answer 40

Wrinkles the skin of hypothenar eminence and deepens the curvature of the hand: improving grip

Question 41

Which artery passes anteriorly from the space between the two heads of adductor pollicis? And what does it forms?

Answer 41

Radial artery - Forms deep palmar arch

Question 42

Action of lumbricals at interphalangeal joint and MCP joint?

Answer 42

IP - extend MCP - flex