Topic 20 - Ulnar Nerve Flashcards
The _____ nerve innervates the following muscles:
- Flexor carpi ulnaris
- Flexor digitorum profundus
- Adductor pollicis
- Small digital muscles
Ulnar
The motor functions of the _____ nerve include:
- Finger adduction
- Finger abduction
- Thumb adduction
- Flexion of digits 4 & 5
- Wrist flexion
- Wrist adduction
Ulnar
The sensory distribution of the ulnar nerve is the skin over the ______ surface of the hand through the superficial branch.
Medial
The ulnar nerve arises from the ______ cord of the brachial plexus. The nerve roots that supply it are ___ and ___.
Medial
C8 & T1
The ulnar nerve exits in the ______ position from the brachial plexus, therefore it tends to avoid ___________ damage.
Lowest
Dislocation
Causes of ulnar nerve lesions at the ________ include:
- Wrenching injuries
- Compression (e.g. crutch use)
Shoulder
Thick fascia that extends from the medial head of the triceps to the intermuscular septum (between the triceps and biceps muscles).
Arcade of Struthers
An area of entrapment in the arm for the ulnar nerve is the arcade of _________.
Struthers
The ulnar nerve is very susceptible to injury at the _____ because of its superficial position and lack of soft tissue protection.
Elbow
Causes of ulnar nerve lesions at the _____ include:
- Banging/falling on it
- Blows
- Dislocations
- Medial epicondylar fractures
Elbow
The ulnar nerve is frequently damaged/compressed as it passes _________ to the medial epicondyle.
Posterior
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).
Cubital Tunnel
Causes of cubital tunnel syndrome include prolonged elbow flexion during sleep known as “_____ _____,” as well as iatrogenic compression.
“Sleep Palsy”
The ulnar nerve can become entrapped between the two heads of FCU and the ulnar portion of _____.
FDP
Causes of ulnar nerve lesions at the _______ include:
- Fractures (especially ulnar)
- Lacerations/blocking injuries (d/t protective stance)
Forearm
Causes of ulnar nerve lesions at the _____ include:
- Fractures
- Dislocations
- Some sprains (especially abduction)
Wrist
The ulnar nerve is very susceptible to all types of hand and finger injuries, especially ___________ to the palm of the hand.
Lacerations
Causes of compression at the ______ of _____ include:
- Entrapment
- Repetitive strain injury
- Laceration
- Carpal bone fracture
- Neural tumor
- Postoperative complication
Tunnel of Guyon
Catchers on softball/baseball teams are vulnerable to ____ of ______ fractures.
Hook of Hamate
Compressive neuropathy of the ulnar nerve in cyclists is known as “_________ _____.”
“Handlebar Palsy”
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)
Ulnar
Which 2 motor actions of the ulnar nerve are also shared with the median nerve?
1) Wrist Flexion
2) Thumb Flexion
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
Ulnar
The ulnar nerve provides sensation to critical areas of the hand - the _______ surface of the hand or _____ border of the small finger.
Resting
Ulnar
The area of isolated supply for the ulnar nerve is ______ ______ and the ulnar border of the hand.
Digiti Minimi
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 ____.
Medial
Hand
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.
Wrist
Ring
T/F - The ulnar nerve does not carry vasomotor fibres.
True
T/F - The ulnar nerve is not critical to normal upper extremity function.
False - The ulnar nerve IS not critical to normal upper extremity function.
The ulnar nerve contributes to intrinsic functions of the hand and also contributes to _____ and ____ strength.
Pinch
Grip
With complete loss of ulnar nerve function, what motor deficit would you see with wrist flexion?
Flaccid Paresis (action shared with median nerve)
With complete loss of ulnar nerve function, what motor deficit would you see with wrist adduction?
Flaccid Paralysis (complete motor loss)
With complete loss of ulnar nerve function, what motor deficit would you see with thumb flexion?
Flaccid Paresis (action shared with median nerve)
With complete loss of ulnar nerve function, what motor deficit would you see with abduction and opposition of digiti minimi?
Flaccid Paralysis (complete motor loss)
With complete loss of ulnar nerve function, what motor deficit would you see with thumb adduction?
Flaccid Paralysis (complete motor loss)
With complete loss of ulnar nerve function, what motor deficit would you see with adduction and abduction of fingers 2-5?
Flaccid Paralysis (complete motor loss)
With complete loss of ulnar nerve function, what motor deficit would you see with flexion of fingers 4 & 5?
Flaccid Paralysis (complete motor loss)
