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Flashcards in Wrist Joint Deck (51):
1

What is the wrist joint also known as?

The radiocarpal joint

2

What kind of joint is the wrist joint?

A synovial joint

3

What does the wrist mark?

The area of transition between the forearm and the hand

4

What is the wrist joint formed by distally?

The proximal row of the carpal bones (except the pisiform)

5

What is the wrist joint formed by proximally?

The distal end of the radius, and the articular disc

6

Is the ulna part of the wrist joint?

No

7

What prevents the ulna from articulating with the carpal bones?

A fibrocartilaginous ligament, called the articular disc, which lies over the superior surface of the ulna

8

What do the carpal bones form together?

A convex surface

9

What shape is the radius and articular disc?

Concave

10

Where does the wrist joint receive blood from?

Branches of the dorsal and palmar carpal arches

11

What are the branches of the dorsal and palmar carpal arches derived from?

The ulnar and radial arteries

12

What is the wrist innervated by?

Medial nerve- anterior interosseous branch 
Radial nerve- posterior interosseous branch 
Ulnar nerve- deep and dorsal branches

13

What contributes to the stability of the wrist?

The joint capsule and ligaments

14

How many layers of the joint capsule of the wrist are there?

Two

15

What does the fibrous outer layer of the joint capsule of the wrist attach to?

The radius, ulna and proximal row of the carpal bones

16

What is the internal layer of the joint capsule of the wrist joint composed of?

A synovial membrane

17

What does the synovial membrane of the wrist joint do?

Secretes synovial fluid which lubricates the joint

18

What are the ligaments of note in the wrist?

Palmar radiocarpal 
Dorsal radiocarpal 
Ulnar collateral 
Radial collateral

19

Where is the palmar radiocarpal ligament found?

On the palmar (anterior) side of the hand

20

Where does the palmar radiocarpal ligament pass?

From the radius to both rows of carpal bones

21

What is the function of the palmar radiocarpal ligament?

Increase stability
Ensure that the hand follows the forearm during supination

22

Where is the dorsal radiocarpal ligament found?

On the dorsum (posterior) side of the hand

23

Where does the dorsal radiocarpal ligament pass?

From the radius to both rows of carpal bones

24

What is the function of the dorsal radiocarpal ligament?

Contributes to the stability of the wrist 
Ensures that the hand follows the forearm during pronation

25

Where does the ulnar collateral ligament run?

From the ulnar styloid process to the triquetrum and pisiform

26

What does the ulnar collateral ligament do?

Works in union with other collateral ligament to prevent excessive lateral joint displacement

27

Where does the radial collateral ligament run?

From the radial styloid process to the scaphoid and trapezium

28

What does the radial collateral ligament do?

Works in union with the other collateral ligament to prevent excessive lateral joint displacement

29

What type of synovial joint is the wrist?

A ellipsoid type

30

What does the joint being an ellipsoid type allow for?

Movement along two axes, meaning that flexion, extension, adduction and abduction can all occur at the wrist joint

31

What are the movements of the wrist performed by?

Muscles of the forearm

32

What produces flexion at the wrist?

Mainly the flexor carpi ulnaris and flexor carpi radialis, with assistance from the flexor digitorum superficialis

33

What produces extension at the wrist?

Mainly by the extensor carpi radialis longus and brevis, and the extensor carpi ulnaris, with assistance from the extensor digitorum

34

What produces adduction at the wrist?

Extensor carpi ulnaris and flexor carpi ulnaris

35

What produces abduction at the wrist?

Abductor pollicis longus, flexor carpi radialis, extensor carpi radialis longus and brevis

36

What happens in the event of the blow to the wrist?

The scaphoid takes most of the force

37

Who is a fractured scaphoid more common in?

The younger population

38

How is the scaphoids blood supply unique?

In runs distal to proximal

39

What can a fracture of the scaphoid disrupt?

The blood supply to the proximal portion

40

What can failure to revascularise the scaphoid lead to?

Avascular necrosis, and future arthritis

41

What is the main clinical sign of a scaphoid fracture?

Tenderness in the anatomical snuffbox

42

How can anterior dislocation of the lunate occur?

Falling on a dorsiflexed wrist

43

What happens when falling on the dorsiflexed wrist?

The lunate is forced anteriorly, and compresses the carpal tunnel

44

What is the result of the compression of the carpal tunnel by the lunate?

Causes the symptoms of carpal tunnel syndrome

45

How does anterior dislocation of the lunate manifest clinically?

Paresthesia in the sensory distribution of the median nerve and weakness of the thenar muscles

46

What is required when there is anterior dislocation of the lunate?

Immediate clinical attention

47

Why is immediate clinical attention required when there is an anterior dislocation of the lunate?

The lunate can undergo avascular necrosis

48

What is the most common pathology involving the wrist?

Colles’ fracture

49

What is the Colles’ fracture caused by?

Falling onto an outstretched hand

50

What can happen with radius fractures, with the distal fragment being displaced posteriorly?

The ulnar styloid process can also be damaged, and is avulsed in the majority of cases

51

What does Colles’ fracture produce?

‘Dinner fork deformity’