L8 - Anatomy of the hand

Question 1

What are the 3 parts of the hand?

Answer 1

Carpals, metacarpals and phalanges

Question 2

What are the carpal bones?

Answer 2

Scaphoid, Lunate, Triquetral, pisiform, trapezium, trapezoid, capitate, hamate

Question 3

What carpal bone is often fractured?

Answer 3

scaphoid - slow recovery - there is poor blood supply to the proximal part - causing avascular necrosis

Question 4

What are the joints of the hand?

Answer 4

Saddle joint 
Carpometacarpal
midcarpal
wrist  - radiocarpal 
interphalangeal 
metacarpophalangeal

Question 5

radiocarpal joint

Answer 5

between the radius and first carpal row
flexion, extension
abduction/adduction
circumduction

Question 6

carpometacarpal joints

Answer 6

For movement of the thumb such as extension, flexion, abduction, adduction, opposition and reposition

Question 7

Ligaments of the wrist joint

Answer 7

ulnar and radial collateral ligaments to limit adduction and abduction and ligaments on the palmar/dorsal surfaces limit extension and flexion

Question 8

metacarpophalangeal joints

Answer 8

flexion/extension

abduction and adduction

Question 9

Interphalangeal joints

Answer 9

PIPS - proximal
DIPS - distal

For flexion and extension

Question 10

Palmar aponeurosis

Answer 10

Thickened deep fascia 
triangular 
continuous with palmaris longus 
both longitudinal and transverse fibres 
Protects nerves

Question 11

what is a consequence of fibrosis of the palmar aponeurosis?

Answer 11

dupuytrens contracture

Question 12

What are the long flexor tendons?

Answer 12

Pass from the muscle in the anterior forearm through the carpal tunnel
Flexor pollicis longus - D1
Flexor digitorum profundus - D2-5
Flexor digitorum superficialis - D2 - 5

Question 13

What is the role of palmaris longus?

Answer 13

flexes the wrist joint

Question 14

Of the anterior forearm. what are the 4 superficial muscle layers called?

Answer 14

FCU - flexor carpi ulnaris
Palmaris Longus
Flexor carpi radialis
pronator teres

Question 15

where does the flexor carpi radialis insert ?

Answer 15

From the medial epicondyle of the humerus to base of 2nd and 3rd metacarple

Question 16

What are the long extensor tendons to digits

Answer 16

come from muscles in the posterior arm
D1 - Extensor pollicis longus, Extensor pollicis brevis, abductor pollicis longus

D2-5 = extensor digitorum, extensor indicis and extensor digiti minimi

Question 17

What are the borders of the anatomical snuff box ?

Answer 17

Medial border: tendon of the EPL - to base of distal phalanx
lateral border: APL (base of 1st metacarpal) and EPB (base of proximal phalanx)

Question 18

Extensor digitorum insertion

Answer 18

medial band inserts into middle phalanx

lateral band inserts into distal phalanx

Question 19

what muscles insert into the extensor hoods?

Answer 19

lumbrical and interosseous

Question 20

What do lumbrical muscles do?

Answer 20

Link the extensor and flexor tendons
Extend the interphalangeal joints and flex the MCP joints
For precision/grip (hold pen/pinch)

Question 21

What do the palmar interossei do?

Answer 21

There are 3
sit between the metacarpals
adduct the MCP joints relative to the middle finger D3
There is no palmar interossei for D1

Question 22

What is the function of dorsal interossei

Answer 22

there are 4
from metacarpals to extensor hoods d2, d3 x2 and d4

ABDUCT MCP joints relative to middle finger
No dorsal interossei for D1 or D5 as it is performed by thenar and hypothenar muscles

Question 23

function of thenar muscles

Answer 23

Fine movement of thumb D1

Question 24

function of hypothenar muscles

Answer 24

fine movements of the little finger D5

Question 25

What are the 3 thenar muscles ?

Answer 25

Deepest one is the Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis

Question 26

What 3 muscles are the hypothenar muscles ?

Answer 26

Deepest - Opponens digiti minimi (into 5th metacarpal)
Abductor digiti minimi
Flexor digiti minimi
Last 2 go to the proximal phalanx

Question 27

Adductor pollicis

Answer 27

Adduction of the thumb
This muscle has an oblique head part that comes from 2nd and 3rd metacarpal and carpal bones and goes to proximal phalanx
The transverse head comes from 3rd metacarpal going to the proximal phalanx

Question 28

Describe the blood supply to the hand?

Answer 28

Radial artery
Ulnar artery
Forms complex anastomosis in the hand

Question 29

Deep palmar arch

Answer 29

Arterial network found in the palm.Formed from the terminal parts of the radial artery with the ulnar artery

Question 30

Where is the deep palmar arch located?

Answer 30

below the long flexor tendons

Question 31

Superficial palmar arch

Answer 31

Found above the long flexor tendons

Question 32

What fingers do the ulnar artery supply?

Answer 32

half of D2 TO D5

Question 33

What fingers do the radial artery supply?

Answer 33

D1 and half of D2

Question 34

What does the median nerve supply?

Answer 34

Passes through carpal tunnel
The recurrent branch of the median nerve supplies the thenar muscles (APB and opponens pollicis)
The digital nerves supply the lateral 2 lumbricals and sensory from d1 to half of d4

Question 35

clinical relevance of median nerve

Answer 35

carpal tunnel syndrome

Question 36

What does the ulnar nerve supply?

Answer 36

Deep branch supplies: 
Hypothenar muscles 
interossei 
medial 2 lumbricals 
adductor pollicis 

Superifical branch supplies:
sensory to half d4 and d5

Question 37

clinical relevance of Ulnar nerve

Answer 37

clawed hand