MSK - Intrinsic Hand Muscles

Question 0

What are the thenor and hypothenor muscles?

Answer 0

The thenor muscles - thumb side

Hypothenor - little finger side

Question 1

What are the intrinsic hand muscles?

Answer 1

These are muscles that originate in the hand and are responsible for precision grip.

Question 2

What lies between the thenor and hypothenor muscles?

Answer 2

The flexor retinaculum

Question 3

What are the three muscles on the palmar side that control the movement of the thumb? And what nerve innervates these

Answer 3

Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis

Median nerve

Question 4

What are the three hypothenor muscles that act on the little finger?

Answer 4

Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi

Question 5

What does the Palmaris brevis do?

Answer 5

Tenses ulnar side of Palm

Creating a hollow in the palm

Question 6

What does the adductor pollicis do?

Answer 6

Adducts the thumb

Question 7

Where are the lumbricals found?

Answer 7

Inbetween the FDP tendons

Look like ‘worms’

Question 8

What is the action of the lumbrical muscles?

Answer 8

Flex at the MCP joint
Extend at the IP joint
They originate on the FDP tendon
YES BOYS!

Question 9

What do the palmar interosseous muscles do?

Answer 9

Adduct the fingers

Question 10

What do the dorsal interosseous muscles do?

Answer 10

Abduct the fingers (index middle and ring)

Question 11

How would you test for palmar IO muscle function?

Answer 11

Stop me pulling this ruler out of your adducted fingers

Question 12

How would you test for dorsal IO muscle function?

Answer 12

Stop me closing your fingers together

Question 13

Where does the median nerve supply?

Answer 13

The first 3.5 fingers palmar surface and the nail beds

This means it supplies the first 2 lumbicles and the hypothenor muscles.

Question 14

Where does the ulnar nerve run in the hand?

Answer 14

Last 1.5 fingers

Supplies the rest of the hand muscles

Question 15

Where does the radial nerve run in the hand?

Answer 15

To the cutaneous areas of the dorsal hand surface (skin sensation)

Question 16

Which two arteries from the forearm run distally into the hand?

Answer 16

The ulnar and the radial artery

Question 17

What are the arches of the hand arteries?

Answer 17

The superficial palmar arch is the main termination of the ulnar artery
The deep palmar arch formed from the radial artery and the deep branch of the ulnar artery

Question 18

What is the digital artery supply?

Answer 18

The common palmar digital arteries

Palmar digital artery (little finger)

Question 19

What is the venous drainage of the hand?

Answer 19

The superficial and deep venous arches drain into the deep vein of forearm.
Dorsal venous network drains into the cephalic from lateral side, basillic arises from the medial side.

Question 20

What structures are in the carpal tunnel?

Answer 20

9 tendons - 
4 from the flexor digitorum profundus 
4 flexor digitorum superficialis 
1 flexor pollicus longus 
Median nerve

Question 21

What is carpal tunnel syndrome?

Answer 21

This is when one of the nine structures enlarges and compresses the median nerve.

Question 22

What are the symptoms of CT syndrome?

Answer 22

Individuals with this cannot
Oppose their thumbs
Difficulty with grip
They have a weakened thumb