Topic 20 - Ulnar Nerve

Question 1

The _____ nerve innervates the following muscles:
- Flexor carpi ulnaris
- Flexor digitorum profundus
- Adductor pollicis
- Small digital muscles

Answer 1

Ulnar

Question 2

The motor functions of the _____ nerve include:
- Finger adduction
- Finger abduction
- Thumb adduction
- Flexion of digits 4 & 5
- Wrist flexion
- Wrist adduction

Answer 2

Ulnar

Question 3

The sensory distribution of the ulnar nerve is the skin over the ______ surface of the hand through the superficial branch.

Answer 3

Medial

Question 4

The ulnar nerve arises from the ______ cord of the brachial plexus. The nerve roots that supply it are ___ and ___.

Answer 4

Medial
C8 & T1

Question 5

The ulnar nerve exits in the ______ position from the brachial plexus, therefore it tends to avoid ___________ damage.

Answer 5

Lowest
Dislocation

Question 6

Causes of ulnar nerve lesions at the ________ include:
- Wrenching injuries
- Compression (e.g. crutch use)

Answer 6

Shoulder

Question 7

Thick fascia that extends from the medial head of the triceps to the intermuscular septum (between the triceps and biceps muscles).

Answer 7

Arcade of Struthers

Question 8

An area of entrapment in the arm for the ulnar nerve is the arcade of _________.

Answer 8

Struthers

Question 9

The ulnar nerve is very susceptible to injury at the _____ because of its superficial position and lack of soft tissue protection.

Answer 9

Elbow

Question 10

Causes of ulnar nerve lesions at the _____ include:
- Banging/falling on it
- Blows
- Dislocations
- Medial epicondylar fractures

Answer 10

Elbow

Question 11

The ulnar nerve is frequently damaged/compressed as it passes _________ to the medial epicondyle.

Answer 11

Posterior

Question 12

Formed by the fascial covering that overlies the ulnar nerve as it travels from superficial (at the elbow) to deep (just distal to the elbow into the forearm between the two heads of FCU).

Answer 12

Cubital Tunnel

Question 13

Causes of cubital tunnel syndrome include prolonged elbow flexion during sleep known as “_____ _____,” as well as iatrogenic compression.

Answer 13

“Sleep Palsy”

Question 14

The ulnar nerve can become entrapped between the two heads of FCU and the ulnar portion of _____.

Answer 14

FDP

Question 15

Causes of ulnar nerve lesions at the _______ include:
- Fractures (especially ulnar)
- Lacerations/blocking injuries (d/t protective stance)

Answer 15

Forearm

Question 16

Causes of ulnar nerve lesions at the _____ include:
- Fractures
- Dislocations
- Some sprains (especially abduction)

Answer 16

Wrist

Question 17

The ulnar nerve is very susceptible to all types of hand and finger injuries, especially ___________ to the palm of the hand.

Answer 17

Lacerations

Question 18

Causes of compression at the ______ of _____ include:
- Entrapment
- Repetitive strain injury
- Laceration
- Carpal bone fracture
- Neural tumor
- Postoperative complication

Answer 18

Tunnel of Guyon

Question 19

Catchers on softball/baseball teams are vulnerable to ____ of ______ fractures.

Answer 19

Hook of Hamate

Question 20

Compressive neuropathy of the ulnar nerve in cyclists is known as “_________ _____.”

Answer 20

“Handlebar Palsy”

Question 21

The order of motor innervation for the _____ nerve is:
1) FCU
2) FDP (medial half)
3) Palmaris Brevis
4) Abductor Digiti Minimi
5) Opponens Digiti Minimi
6) Flexor Digiti Minimi
7) Interossei (PADs & DABs)
8) Lumbricals (fingers 4 & 5)
9) Adductor Pollicis
10) Flexor Pollicis Brevis (deep half)

Answer 21

Ulnar

Question 22

Which 2 motor actions of the ulnar nerve are also shared with the median nerve?

Answer 22

1) Wrist Flexion
2) Thumb Flexion

Question 23

The following motor actions are solely innervated by the _____ nerve:
- Wrist Adduction
- Abduction & Opposition of Digiti Minimi
- Thumb Adduction
- Adduction & Abduction of Fingers 2-5
- Flexion of Fingers 4 & 5

Answer 23

Ulnar

Question 24

The ulnar nerve provides sensation to critical areas of the hand - the _______ surface of the hand or _____ border of the small finger.

Answer 24

Resting
Ulnar

Question 25

The area of isolated supply for the ulnar nerve is ______ ______ and the ulnar border of the hand.

Answer 25

Digiti Minimi

Question 26

The primary zone for the ulnar nerve is the ______ 1/2 of the ring finger (anterior and posterior), as well as strips of the palmar and dorsal surfaces of the ____.

Answer 26

Medial
Hand

Question 27

The proprioception for the ulnar nerve is the medial aspect of the _____ joint, majority of the 5th digit and the anterior joint surfaces of the ____ finger.

Answer 27

Wrist
Ring

Question 28

T/F - The ulnar nerve does not carry vasomotor fibres.

Answer 28

True

Question 29

T/F - The ulnar nerve is not critical to normal upper extremity function.

Answer 29

False - The ulnar nerve IS not critical to normal upper extremity function.

Question 30

The ulnar nerve contributes to intrinsic functions of the hand and also contributes to _____ and ____ strength.

Answer 30

Pinch
Grip

Question 31

With complete loss of ulnar nerve function, what motor deficit would you see with wrist flexion?

Answer 31

Flaccid Paresis (action shared with median nerve)

Question 32

With complete loss of ulnar nerve function, what motor deficit would you see with wrist adduction?

Answer 32

Flaccid Paralysis (complete motor loss)

Question 33

With complete loss of ulnar nerve function, what motor deficit would you see with thumb flexion?

Answer 33

Flaccid Paresis (action shared with median nerve)

Question 34

With complete loss of ulnar nerve function, what motor deficit would you see with abduction and opposition of digiti minimi?

Answer 34

Flaccid Paralysis (complete motor loss)

Question 35

With complete loss of ulnar nerve function, what motor deficit would you see with thumb adduction?

Answer 35

Flaccid Paralysis (complete motor loss)

Question 36

With complete loss of ulnar nerve function, what motor deficit would you see with adduction and abduction of fingers 2-5?

Answer 36

Flaccid Paralysis (complete motor loss)

Question 37

With complete loss of ulnar nerve function, what motor deficit would you see with flexion of fingers 4 & 5?

Answer 37

Flaccid Paralysis (complete motor loss)