Anterior Forearm

Question 1

what demarcates the posteromedial boundary separating the flexor-pronator (anterior) and extensor-pronator (posterior) compartments?

Answer 1

posterior border of ulna

Question 2

where can pulsations of the radial artery be palpated?

Answer 2

superficial to the cubital fossa

Question 3

where does the anterolateral boundary lie?

Answer 3

cubital fossa, anterior to radial styloid

Question 4

how far distal is the radial styloid process from the ulnar styloid process?

Answer 4

1cm

Question 5

what does not participate in the wrist (radoiocarpal) joint?

Answer 5

ulna

Question 6

what is the most common fracture of the forearm?

Answer 6

colles fracture (complete transverse fracture of distal 2cm of radius)

Question 7

how does Colles fracture manifest?

Answer 7

forced dorsiflection of the hand

dinner fork deformity

Question 8

what happens to the radial styloid process during a Colles fracture?

Answer 8

it projects proximal to the ulnar styloid process (since the radius is shortened)

Question 9

flexors are what?

Answer 9

anterior - median nerve

Question 10

extensors are what?

Answer 10

posterior - radial nerve

Question 11

what is the antebrachial fascia that goes posteriorly?

Answer 11

extensor retinaculum

Question 12

what is the antebrachial fascia that goes anteriorly?

Answer 12

palmar carpal ligament

Question 13

what is the antebrachial fascia inferior to the palmar carpal ligament?

Answer 13

flexor retinaculum (transverse carpal ligament)

Question 14

what antebrachial fascia helps make the carpal tunnel

Answer 14

flexor retinaculum

Question 15

what passes through the carpal tunnel?

Answer 15

• median nerve

- flexor tendons

Question 16

what is the deep fascia beyond the extensor retinaculum and flexor retinaculum?

Answer 16

palmar fascia

Question 17

what is the thick, triangular, tendinous central part of the palmar fascia that overlies the central part of the palm?

Answer 17

palmar aponeurosis

Question 18

what is the apex of the palmar aponeurosis?

Answer 18

palmaris longus

Question 19

anterior compartment innervation

Answer 19

• median nerve

- ulnar nerve (1 and a half anterior forearm muscles)

Question 20

posterior compartment innervation

Answer 20

deep radial nerve

Question 21

superficial flexor-pronator muscles

Answer 21

• pronator teres
• flexor carpi radialis
• palmaris longus
• flexor carpi ulnaris

Question 22

superior flexor-pronator muscle attachment

Answer 22

common flexor tendon to medial epicondyle

Question 23

intermediate flexor-pronator muscle

Answer 23

• flexor digitorum superficialis

- humeral head

Question 24

deep flexor-pronator muscles

Answer 24

• flexor digitorum profundus
• flexor pollicis longus
• pronator quadratus

Question 25

what does the lateral border of the pronator teres form?

Answer 25

medial boundary of cubital fossa

Question 26

compression of the median nerve with pain and tenderness in proximal aspect of the anterior forearm

Answer 26

pronator syndrome

Question 27

flexor carpi radialis action

Answer 27

- flexion (with flexor carpi ulnaris) - abduction of wrist (with extensor carpi radials longus/brevis) - flexion/abduction combo when alone (anterolateral)

Question 28

what is a good guide to the radial artery?

Answer 28

flexor carpi radialis

Question 29

what does the FCR pass through?

Answer 29

-lateral part of flexor retinaculum -vertical groove in trapezium (has own synovial tendinous sheath of FCR)

Question 30

which forearm muscle is sometimes absent?

Answer 30

palmaris longus

Question 31

what is a good guide to the median nerve?

Answer 31

palmaris longus

Question 32

flexor carpi ulnaris action

Answer 32

- flexes wrist with FCR | - ADducts with ECR

Question 33

where does the ulnar nerve enter the forearm?

Answer 33

between humeral and ulnar heads

Question 34

which muscle is fully innervated by the ulnar nerve?

Answer 34

FCU

Question 35

what syndrome compresses the ulnar nerve?

Answer 35

cubital tunnel syndrome

Question 36

flexor digitorum superficialis attachement

Answer 36

common flexor origin

Question 37

what is the largest superficial muscle in the forearm?

Answer 37

FDS

Question 38

FDS innervation

Answer 38

- median nerve | - ulnar nerve

Question 39

what encloses the FDS and FDP tendons in the carpal tunnel?

Answer 39

synovial common flexor sheath

Question 40

FDS action

Answer 40

- flexes middle phalanges of medial 4 fingers at PIPs | - flexes proximal phalanges at MCP joints and wrist joint

Question 41

which is the only muscle that can flex the distal interphalangeal joints of the fingers?

Answer 41

flexor digitorum profundus

Question 42

which muscle can flex DIP, PIP, MCP, and wrist joint?

Answer 42

flexor digitorum profundus

Question 43

which tendon is flat and passes deep to the flexor retinaculum on the lateral side of the common flexor sheath?

Answer 43

flexor pollicis

Question 44

which is the only muscle that flexes the distal phalanx of the thumb?

Answer 44

flexor pollicis

Question 45

which muscle flexes the proximal phalanx at the MCP joint and 1st metacarpal at the carpometacarpal joint?

Answer 45

flexor pollicis

Question 46

which is the deepest muscle in the anterior forearm?

Answer 46

pronator quadratus

Question 47

pronator quadratura action

Answer 47

pronation (with pronator teres)

Question 48

main forearm arteries

Answer 48

radial and ulnar arteries

Question 49

branches of which arteries participate in the periarticular anastomosis of the elbow?

Answer 49

branches of the ulnar artery

Question 50

what supplies the muscles of the medial and central forearm and common flexor sheath?

Answer 50

branches of ulnar artery

Question 51

what do anterior ulnar recurrent arteries anastomose with?

Answer 51

inferior ulnar collateral arteries

Question 52

what do posterior ulnar recurrent arteries anastomose with?

Answer 52

superior ulnar collateral arteries

Question 53

what does the radial recurrent artery anastamose with?

Answer 53

radial collateral artery (branch of the deep artery of the arm)

Question 54

in 3% of people, what does the ulnar artery do?

Answer 54

descends superficial to the flexor muscles | need to be careful drawing blood and inserting drugs

Question 55

fractured medial epicondyle and other ulnar nerve injuries cause what?

Answer 55

- difficulty making a fist - no extension of interphalangeal joints - atrophy of interosseous muscles - numbness and paresthesia middle part of palm and medial one and a half fingers "claw hand"

Question 56

what kind of innervation does radial nerve serve?

Answer 56

- motor and sensory in arm and forearm | - ONLY sensory in hand

Question 57

2 branches of forearm radial nerve

Answer 57

- sensory/cutaneous = superficial branch | - motor = deep radial/posterior interossesous nerve branch

Question 58

humeral shaft fracture

Answer 58

radial nerve -wrist drop