PNI Videos

Question 1

name 3 indications of ulnar nerve injury.

Answer 1

• claw hand
• wartenberg’s sign
• unable to cross fingers

Question 2

in ulnar nerve injuries there may be wasting of which muscles?

Answer 2

first interossei

Question 3

claw hand deformity may occur if the injury occurs where?

Answer 3

ulnar nerve below the elbow

Question 4

why does the claw hand occur?

Answer 4

FDP works but intrinsics that straighten the fingers are not working - FDP takes over and causes clawing of the fingers

Question 5

claw hand is only seen when?

Answer 5

when there is an active attempt to flew the fingers - when hand is relaxed/extended, claw appearance disappears

Question 6

in a distal ulnar nerve injury you lose innervation to which muscles?

Answer 6

all interosseii and the ulnar 2 lumbricals

Question 7

what is wartenberg’s sign?

Answer 7

abduction of the 5th finger - due to ulnar nerve palsy

Question 8

wartenberg’s sign is caused by what?

Answer 8

an unopposed action of the ulnar insertion of extensor digiti minimi, the interosseous muscle that adducts the finger is not working

Question 9

which muscle is “lost” in wartenberg’s sign?

Answer 9

fifth interosseous muscle

Question 10

which interossei muscles adduct?

Answer 10

palmar (PAD)

Question 11

which interossei muscles abduct fingers?

Answer 11

dorsal interossei (DAB)

Question 12

froment’s test is used to test for what?

Answer 12

ulnar nerve palsy/cubital tunnel syndrome

Question 13

describe a positive froment’s sign.

Answer 13

thumb IP joint will flex if adductor pollicis muscle is weak due to an ulnar nerve palsy

Question 14

name 2 indications of a high median nerve injury/anterior interosseous nerve injury.

Answer 14

• sign of benediction

- cannot do the ok sign

Question 15

prolonged compression or injury of the median nerve may result in what?

Answer 15

sign of benediction

Question 16

when does the sign of benediction occur?

Answer 16

when a pt. with a high median nerve injury is trying to make a fist

Question 17

which muscles are paralyzed in the sign of benediction?

Answer 17

• FDS
• FPL
• FPB
• radial half of the FDP

Question 18

why are digits 4 and 5 flexed during the sign of benediction?

Answer 18

the only remaining functioning flexor muscle is the ulnar half of the FDP - flexes digits 4 and 5

Question 19

ulnar claw hand refers to damage of the ulnar nerve ___ the elbow.

Answer 19

below

Question 20

ulnar claw hand occurs when the pt. is attempting to ___ all the digits.

Answer 20

extend

Question 21

name 2 default positions (conditions) of the injured hand at rest.

Answer 21

• claw hand

- ape hand

Question 22

in ape hand, which muscle moves the thumb?

Answer 22

adductor pollicis - even though it is an ulnar nerve innervated muscle - brings thumb into the same plane at the other digits

Question 22

in ape hand, which muscle moves the thumb?

Answer 22

adductor pollicis - even though it is an ulnar nerve innervated muscle - brings thumb into the same plane at the other digits

Question 23

which test tests for anterior interosseous nerve injury?

Answer 23

ok sign

Question 24

pt with paralysis of which nerve is unable to make an ok sign?

Answer 24

anterior interosseous nerve injury

Question 25

which muscles are paralyzed in the ok sign/anterior interosseous nerve injury?

Answer 25

FPL and lateral part of flexor digitorum

Question 26

a high radial nerve injury will cause what?

Answer 26

wrist drop

Question 27

high radial nerve injuries usually occur due to what?

Answer 27

fractures of the distal third of the humeral shaft

Question 28

what is a fracture of the distal third of the humeral shaft known as?

Answer 28

holstein-lewis fracture

Question 29

a holstein-lewis fracture will result in paralysis of what?

Answer 29

the wrist and finger extensors

Question 30

the patient will not be able to do what in a holstein-lewis fracture?

Answer 30

hitchhike position or finger extension

Question 31

a low radial nerve injury affects what?

Answer 31

fingers and thumb extension

Question 32

which nerve is affected in low radial nerve injuries?

Answer 32

posterior interosseous nerve

Question 33

if a patient does not have wrist drop and still cannot perform the hitchhike sign then check for what?

Answer 33

posterior interosseous nerve injury

Question 33

if a patient does not have wrist drop and still cannot perform the hitchhike sign then check for what?

Answer 33

posterior interosseous nerve injury