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Flashcards in Anterior Forearm and Palmer Hand Deck (75)
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1
Q

Which group of muscles crosses the elbow?

A

superficial group, deep group does NOT

2
Q

What is the innervation rule for the anterior forearm?

A

“mostly median” C6-T1

exception: 1.5 muscles are innervated by ulnar nerve (flexor carpi ulnaris and ulnar half of flexor digitorum profundus)

3
Q

What are the actions of the anterior compartment of the forearm?

A

Flex wrist joint

Flex fingers

Pronation

Abduction/Adduction of wrist joint

4
Q

Where do the SF muscles of the anterior forearm originate?

A

Medial epicondyle of the humerus

5
Q

What is medial epicondylitis?

A

AKA “golfer’s elbow”

inflammation of the common flexor origin and periosteum of the medial epicondyle

6
Q

What muscles make up the SF group of the anterior compartment of the forearm?

A

pronator teres

flexor carpi radialis

flexor carpi ulnaris

palmaris longus

flexor digitorum superficialis

7
Q

Insertion of pronator teres?

A

lateral radius

8
Q

Action of pronator teres?

A

protonate forearm

9
Q

Insertion of flexor carpi radialis?

A

radial side of hand

10
Q

Action of flexor carpi radialis?

A

flex wrist joint, abduct wrist joint

11
Q

Insertion of flexor carpi ulnaris?

A

ulnar side of hand

12
Q

Action of flexor carpi ulnaris?

A

flex wrist joint, adduct wrist

13
Q

What innervates flexor carpi ulnaris?

A

ulnar nerve

exception to innervation rule

14
Q

Which muscle of the anterior forearm is missing in 15% of ppl? Where does this muscle insert?

A

palmaris longus

palmar aponeurosis

15
Q

Action of palmaris longus?

A

flex wrist joint

16
Q

Insertion of flexor digitorium superficialis?

A

middle phalanges of digits 2-5

17
Q

Actions of flexor digitorum superficialis?

A

flex digits 2-5 at MCP & PIP joints

flex wrist joint

18
Q

What are the origins of the deep group of the anterior compartment of the forearm?

A

ulna, radius, interosseous membrane

do not cross elbow

19
Q

What are the muscles of the deep group of the anterior forearm?

A

flexor digitorum profundus

flexor pollicis longus

pronator quadratus

20
Q

Insertion of flexor digitorum profundus?

A

distal phalanges of digits 2-5

21
Q

Actions of flexor digitorum profundus

A

flex digits 2-5 at MCP, PIP & DIP joints

flex wrist joint

22
Q

How can you test flexor digitorum profundus (FDP)?

A

have pt flex DIP joint

digits 2&3: median nerve, digits 4&5 ulnar nerve

23
Q

How can you test flexor digitorum superficialis (FDS)?

A

have pt flex PIP joint

24
Q

What innervates flexor digitorum profundus?

A

radial 1/2 (digits 2 &3): median nerve

ulna 1/2 (digits 4&5): ulnar nerve

25
Q

Action of flexor pollicis longus?

A

Flex pollex, flex wrist joint

26
Q

Insertion of pronator quadratus?

A

distal radius

27
Q

Action of pronator quadratus?

A

pronate forearm

28
Q

What is the flexor retinaculum?

A

band of deep fascia holding long flexor tendons in place as they cross the wrist joint

tendons are surrounded by synovial sheaths to permit movement

29
Q

What forms the roof of the carpal tunnel?

A

flexor retinaculum

30
Q

What are the contents of the carpal tunnel?

A

9 tendons & median nerve:

tendons of FDSF (4)
tendons of FDP (4)
tendon of flexor pollicis longus (1)

31
Q

What are the compartments of the palm?

A

thenar compartment

adductor compartment

hypothenar compartment

central compartment

interosseous compartments

32
Q

Central compartment of palm

A

deep to palmar aponeurosis

contains long flexor tendons (FDSF, FDP) and lumbricals

33
Q

Where can infections of the central compartment of the hand spread to? how?

A

infections can travel deep to flexor retinaculum through carpal tunnel and into the anterior forearm

34
Q

Interosseous compartments of palm

A

between metacarpals, contain interossei

35
Q

Thenar compartment of palm

A

contains 3 thenar muscles, act on thumb

36
Q

Adductor compartment of palm

A

contains adductor pollicis muscle

37
Q

hypothenar compartment of palm

A

contains 3 hypothenar muscles, acting on digit 5

38
Q

What innervates the intrinsic muscles of the hand?

A

most are innervated by ulnar nerve (C8-T1) but some are innervated by the median nerve (C8-T1)

39
Q

What are the thenar muscles>

A

Abductor pollicis brevis

Flexor pollicis brevis

opponens pollicis

40
Q

What innervates the thenar muscles?

A

recurrent branch of the median nerve

41
Q

What movements can occur at the CMC joint of the pollex?

A

Flexion/Extension

Abduction/Adduction

Opposition/Reposition

42
Q

Actions of abductor pollicis brevis?

A

abduct thumb at CMC joint

43
Q

Action of flexor pollicis brevis?

A

flex thumb at CMC and MCP joints

44
Q

Action of opponens pollicis?

A

opposition of thumb (CMC joint)

45
Q

What makes up the adductor compartment of the palm?

A

1 muscle: adductor pollicis (oblique and transverse heads)

46
Q

What innervates adductor pollicis?

A

ulnar nerve

47
Q

Action of adductor pollicis?

A

Adduct thumb

48
Q

What makes up the hypothenar compartment of the palm?

A

3 “digiti minimi” muscles:

  • Abductor digiti minimi
  • Flexor digiti minimi brevis
  • Opponens digiti minimi
49
Q

What innervates the hypothenar muscles?

A

the ulnar nerve

50
Q

Action of abductor digiti minimi?

A

abduct digit 5 at MCP joint

51
Q

Action of flexor digiti minimi brevis?

A

flex digit 5 at CMC and MCP joints

52
Q

Action of opponens digit minimi?

A

opposition of digit 5 (CMC) joint

53
Q

What are the muscles of the central compartment of the palm?

A

lumbricals (n=4) originate on the tendons of FDP and insert on the extensor expansions of digits 2-5

54
Q

Action of lumbricals?

A

Flex MCP joint and extend PIP &DIP joints of digits 2-5

55
Q

What innervates the lumbricals?

A

medial nerve (radial 1/2)

ulnar nerve (ulnar 1/2)

56
Q

What innervates the interossei?

A

ulnar nerve

57
Q

Action of interossei?

A

PAD: palmar interossei (3) adduct digits 2, 4 and 5

DAB: dorsal interossei (4) abduct digits 2-4

58
Q

What does the median nerve innervate?

A

courses through cubital fossa and innervates most of the muscles of the anterior forearm

recurrent branch-thenar muscles

common and proper digital nerves- motor to lumbricals to digits 2&3, sensory to skin on lateral palm and lateral 3.5 digits

Does NOT innervate structures in the arm

59
Q

Compression of what nerve leads to carpal tunnel syndrome?

A

median nerve

60
Q

What will occur if there is a proximal lesion of the median nerve?

A

pronation lost

flexion and abduction of wrist dramatically weakened

flexion of MCPs, PIPs and DIPs of digits 2-3 lost, flexion of MCPs and PIPs

flexion and opposition of thumb lost

abduction of thumb weakened

lumbricals of digits 2 & 3 paralyzed

skin on lateral palm and lateral 3.5 digits anesthetized

61
Q

What causes carpal tunnel syndrome?

A

any significant reduction in the size of the carpal tunnel, such as inflammation of the synovial sheaths of the flexor tendons

62
Q

clinical presentation of carpal tunnel syndrome

A

progressive weakening of thenar muscles which weaken grip

loss of sensation on lateral 3.5 digits also affects grip

63
Q

treatment of carpal tunnel syndrome

A

usually conservative treatment but can require surgery-partial to full opening of the flexor retinaculum

64
Q

What does the ulnar nerve innervate

A

Flexor carpi ulnaris and ulnar .5 of FDP (digits 4&5)

does not innervate structures in the arm

65
Q

Where does the ulnar nerve travel?

A

posterior to the medial epicondyle in the cubital tunnel (can be compressed here-cubital tunnel syndrome)

travels superficial to the flexor retinaculum with the ulnar artery

66
Q

What do the branches of the ulnar nerve innervate?

A

deep branch: motor to hypothenar muscles, all interossei, lumbricals to digits 4&5 and adductor pollicis

common and proper digits nn: sensory to skin on ulnar palm, and ulnar 1.5 digits and ulnar aspect of dorsal hand

67
Q

What will a proximal lesion of the ulnar nerve result in?

A

flexion &adduction of wrist weakened

flexion of DIPs of digits 4-5 lost

flexion of MCP & PIPs of digits 4-5 weakened

affects grip (hypothenar/adductor pollicis)

interossei paralyzed- no abduction/adduction

lumbricals to digits 4&5

skin of medial pal and 1.5 digits

68
Q

How can you test for a proximal lesion of the ulnar nerve?

A

abduct/adduct digits 2-5, cutaneous sensation of tip of digit 5

69
Q

How can you test for a proximal lesion of the median nerve?

A

pad-pad opposition of thumb, cutaneous sensation tip of digit 2

70
Q

What does the brachial artery give rise to in the cubital fossa?

A

ulnar and radial arteries

71
Q

What are the main branches off the ulnar artery?

A

ulnar recurrent aa.

common interosseous a.

superficial palmer arch

72
Q

What does the SF palmar arch give off?

A

common and proper digits aa. which anastomose with the deep palmer arch from the radial a.

73
Q

What does the common interosseous artery give off?

A

the anterior and posterior interosseous artery

74
Q

What are the branches off the radial artery?

A

radial recurrent a

deep palmer arch- anastomoses with SF palmer arch

75
Q

Where can you palpate the radial pulse?

A

lateral to the tendon of flexor carpi radialis