Anatomy of Hand and Wrist

Question 1

What is the only joint of pronation and supination in the hand and wrist

Answer 1

Radio-ulnar joint

Question 2

Arteries in the arm (when do they get a new name?)

Answer 2

Subclavian –> axillary at lat. border of 1st rib
Axillary –> brachial at inf. border of teres minor
Brachial –> divdes into radial and ulnar at cubital fossa
Radial & Ulnar –> forms deep and superficial palmar arches, gives of digital artery branches (run down fingers)

Question 3

Superficial veins in arm

Answer 3

Superficial veins from dorsal venous arch
Cephalic - travels laterally and drains into axillary below clavicle
Basilic - travels medially and becomes continuous with brachial veins
Median cubital vein - connects cephalic and basilica in cubital fossa

Question 4

Lymphatic drainage of the arms

Answer 4

Right Arm –> right lymphatic duct

Left Arm –> thoracic duct

Question 5

Glenohumeral joint type and movement

Answer 5

Synovial ball and socket
Flexion - extension
Abduction - adduction
Circumduction

Question 6

Elbow joint type and movement

Answer 6

Synovial hinge

Flexion - extension

Question 7

Proximal and distal radioulnar joint type and movement

Answer 7

Synovial pivot

Pronation - supination

Question 8

Wrist joint type and movement

Answer 8

Synovial condyloid
Flexion - extension
Abduction - adduction
Circumduction

Question 9

Carpo-metacarpal (1st) joint type and movement

Answer 9

Synovial saddle 
Flexion - extension 
Abduction - adduction 
Circumduction 
Opposition

Question 10

Carpo-metacarpal (2-5th) joint type and movement

Answer 10

Synovial condyloid

Flexion - extension

Question 11

Interphalangeal joint type and movement

Answer 11

Synovial condyloid

Flexion - extension

Question 12

What muscles are in the superficial layer of the forearm flexors (lateral - medial) and what are their actions

Answer 12

Pronator teres - pronation
Flexor carpi radialis - abduction
Palmaris longus - tightens palmar aponeurosis (flexion)
Flexor carpi ulnaris - adduction

Question 13

What muscle is in the intermediate layer of the forearm flexors (lateral - medial) and what is its action

Answer 13

Flexor digitorum superficialis - flexes the PIP, MCP and wrist joints

Question 14

What muscles are in the deep layer of the forearm flexors and what are their actions

Answer 14

Supinator - supination
Flexor Pollicis Longus - flexes thumb phalanges, assists in flexing the wrist when thumb is fixed
Flexor Digitorum Profundus - flexes DIP, PIP, MCP and wrist joints

Question 15

What muscle is in the distal deep layer of the forearm flexors and what is its action

Answer 15

Pronator quadratus - pronation

Question 16

What muscles can be found in the posterior compartment and what are their actions

Answer 16

Extensor carpi ulnaris - adduction
Extensor carpi radialis - abduction
Biceps brachi - supination
Supinator - supination

Question 17

What muscles can be found in the intermediate posterior compartment of the forearm and what are their actions

Answer 17

Extensor digiti minimi - extension of little finger at MCP and IP joints
Extensor digitorum - extends IP (mostly proximal) and wrist joints

Question 18

What is the carpal tunnel and what does it contain - what causes carpal tunnel syndrome

Answer 18

The carpal tunnel is bound by the flexor retinaculum and the carpal bones and contains 9 tendons (FDS, FDP, FPL) and the median nerve.
If any of the tendons swell or degenerate, the narrowing of the carpal tunnel can lead to the median nerve becoming compressed causing pain in wrist

Question 19

What nerves innervate muscles in the upper arm

Answer 19

Musculocutaneous nerve - flexors

Radial nerve - extensors

Question 20

What nerves innervate muscles in the forearm

Answer 20

Flexors - median and ulnar 
Extensors - radial 
Brachioradialis - radial 
Brachialis - radial 
FCU & FDP (ulnar half) - ulnar

Question 21

What are the thenar muscles, what is there actions and what are they innervated by

Answer 21

Flexor Pollicis Brevis - median
Abductor Pollicis Brevis - median
Opponens Pollicis - median
Adductor Pollicis - ulnar

Question 22

What are the hypothenar muscles, what is there actions and what are they innervated by

Answer 22

Flexor digiti minimi - ulnar
Abductor digiti minimi - ulnar
Opponens digiti minimi - ulnar

Question 23

Action of Interossei

Answer 23

Palmar - adduction

Dorsal - abduction

Question 24

Action of lumbricals

Answer 24

Simultaneously flex MCP joints and extend PIP joints

Question 25

Clinical relevance of trapezium

Answer 25

Common site of arthritis

Question 26

Clinical relevance of scaphoid

Answer 26

Common fracture site and difficult to heal due to its retrograde blood supply (branch from radial a. comes from distal to proximal), means proximal part is prone to avascular necrosis –> poor healing –> arthritis

Question 27

Borders and Contents of anatomical snuffbox

Answer 27

Borders - EPL, EPB, APL
Contents 
- radial artery 
- styloid process of radius 
- trapezium 
- scaphoid 
- base of 1st metacarpal

Question 28

What muscle is used for a landmark in radial fractures

Answer 28

Flexor carpi radialis

Question 29

What is the palmaris Longus test

Answer 29

Slightly flex wrist, oppose thumb and little finger

Question 30

How to test flexor digitorum profundus

Answer 30

Only tendon to act on distal IP joint so flex DIPJ

Question 31

How to test flexor digitorum superficialis

Answer 31

Hold fingers out straight to isolate FDS (FDP also acts on PIPJ) and flex proximal IP joint

Question 32

What is Allens test

Answer 32

Done before using radial artery for repeated ABGs or arterial lines - shows ulnar nerve can perfuse hand.
Make fist and occlude radial and ulnar arteries. Release ulnar artery. Hand should reperfuse within 5-15 seconds