PBL Week 2

Question 1

What are the ligaments of the hand and wrist

Answer 1

• collateral ligaments on either side of fingers
• Volar plate = ligament connecting the proximal phalanx to the middle phalanx on the palmar side
• Radial and ulnar collateral ligaments support either side of the wrists
• Volar radiocarpal ligaments = web of ligaments that support palmar aspect of ribs
• Dorsal radiocarpal ligaments = support the back of the wrist
• Ulnocarpal ligament
• Radioulnar ligament

Question 2

What are the main tendons supporting the hand

Answer 2

• superficialis tendons (on palmar aspect and attach to middle phalanges
• Profundus tendons ( same as above but attach at the distal phalanges
• Lots of flexor tendons
• Lots of extensor tendons

Question 3

What gives rise to the superficial palmar arch

Answer 3

Predominantly the ulnar artery

Question 4

What gives rise to the deep palmar arch

Answer 4

Primarily the radial artery but through an anastomoses ulnar artery also does give a contribution

Question 5

What does the superficial palmar branch give rise to

Answer 5

Common palmar digital arteries

Question 6

What do common palmar digital arteries give rise to

Answer 6

Proper palmar digital arteries

Question 7

What is phalens test

Answer 7

Forced Flexion of the wrist for 60 seconds elicits signs of carpal tunnel syndrome

Question 8

What is neuropraxia

Answer 8

Conduction block in which the nerve is still in continuation

Question 9

What is axonotmesis

Answer 9

Axon is not continuous but nerve is still intact

Question 10

What is neurotmesis

Answer 10

Complete rupture of nerve

Question 11

What is the patient unable to do if there is median nerve damage

Answer 11

Unable to make a fist, lateral two fingers able to flex as are under ulnar nerve control

Hand of benediction

Question 12

Ulnar nerve injury is characterised by

Answer 12

Clawed hand. 4th and 5th digit not able to extend = permanent flexion

Question 13

What does radial nerve injury present as

Answer 13

Wrist drop

Not able to extend wrist and hangs flaccidly

Question 14

What is wallerian degeneration

Answer 14

Preparing the distal stump for reinnervation by Schwann cells and macrophages clearing up any debris

Formation of endoneural tubes and chromatolysis of cell body occurs.

Cell produces molecules for growth and repair such as Tubulin and actin

Axon regeneration - formation of a growth cone. Growth cone has protease which is able to digest any further debris in the way. Chromatolysis is reversed at this point

Question 15

How many carpal bones

Answer 15

8

Question 16

How many metacarpals

Answer 16

5

Question 17

How many phalanges

Answer 17

14

Question 18

What bones are in the proximal row of the wrist

Answer 18

Scaphoid
Lunate
Triquetrum
Pisiform

Question 19

What bones are in the distal row of the wrist

Answer 19

Hamate
Capitate (largest carpal and in line with 3rd metacarpal)
Trapezoid
Trapezium

Question 20

What are the type of joints in the hand

Answer 20

Wrist = synovial

Carpal joints = synovial

CMC = 1 saddle joint between 1st metacarpal and trapezium
4 plane synovial joints

MCP = condylar joints

Interphalangeal joints = hinge joints

Question 21

Which 9 tendons pass through the carpal tunnel

Answer 21

4 tendons of flexor digitorum superficialis
4 tendons of flexor digitorum profundus
1 tendon of flexor pollicis longus

Question 22

How many interosseous muscles are there

Answer 22

4 dorsally and 3 volarly

Question 23

What attaches to the lumbricals

Answer 23

Tendons of flexor digitorum profundus (deep)