Upper Limb Nerve Injuries

Question 1

Lower motor neuron arises from?

Answer 1

Anterior horn cell

Question 2

UMN vs LMN?

Answer 2

UMN- flexed posture if chronic, increased tone, brisk reflexes and sensory level

LMN- wasting fasciculations, flaccid tone, reduced reflexes, weakness in either a myotonia distribution or a peripheral nerve distribution, dermatomal or peripheral nerve distribution of sensory loss

Question 3

What are pyramidal weakness?

Answer 3

Flexor muscles stronger than extensors

Question 4

C5 myotome corresponds to?

Answer 4

Deltoid for shoulder abduction

Question 5

C6 myotome corresponds to?

Answer 5

Biceps, brachial is and brachioradialis- for elbow flexion

Question 6

C7 corresponds to?

Answer 6

Triceps superficial forearm extensors and superficial forearm flexors- elbow extension, wrist extension and flexion

Question 7

C8 corresponds to

Answer 7

Forearm extensors, deep forearm flexors- finger extension/ flexion

Question 8

T1 corresponds to?

Answer 8

Intrinsic hand muscles- finger abduction

Question 9

Biceps reflex?

Answer 9

C5 reflex conveyed through musculocutaneous nerve

Question 10

Supination jerk?

Answer 10

C6 reflex through radial nerve

Question 11

Triceps jerk?

Answer 11

C7 reflex conveyed through radial nerve

Question 12

Finger jerk?

Answer 12

C8 reflex conveyed through median and ulnar nerve

Question 13

Nerve root impingement can cause?

Answer 13

Sensory loss, weakness and reflex loss and pain

Question 14

Avulsion injury?

Answer 14

Root gets pulled off cord

Question 15

Neuropraxia?

Answer 15

Stretching injury of nerve, damaging myelin, so impaired transmission

Question 16

Neuromas?

Answer 16

Primary tumours of nerve and nerve sheath, connective tissue growth, causing compression

Question 17

Rupture can be of?

Answer 17

Axon, complete resectioning of the nerve

Question 18

Motor cycle injury causes?

Answer 18

Flail arm , so wasting of deltoid and supraspinatus

Question 19

Erbs palsy?

Answer 19

Traumatic injury of C5-C6, shoulders get stuck or falling out of bed.

Weakness of muscles, but preserved hand functions

Otherwise known as waiter’s tip

Question 20

Klumpke’s palsy?

Answer 20

Clutching an object falling from height

Injury to C8 T1

Supplying median nerve and ulnar nerve

Preserves arm, but fingers or wrist unable to flex, weakness of small muscles of the hand and sensory loss hand and inner border of forearm

Could cause claw hand

Question 21

What else can cause nerve injuries?

Answer 21

Pancoast tumours,
Pain in shoulder girdle and inner arm

important to look for ipsilateral horners syndrome T1

Question 22

Radiation induced brachial plexopathy?

Answer 22

Mean 6 years post radiation
Pain is not a feature
Predilection for upper brachial plexus

Question 23

Idiopathic brachial neuritis?

Answer 23

Inflammation affects random parts of brachial plexus, varies with root and nerve

Severe pain over days, as diminishes followed by weakness and wasting

Mono-basic recurrent, asymmetrical, thickening and enhancement

Question 24

Thoracic outlet syndrome?

Answer 24

Compression sites between:

1. Between anterior and middle scalene muscles
2. Beneath clavicle in the costoclavicular space
3. Beneath tendon of pec minor

Question 25

Neurogenic thoracic outlet syndrome can cause?

Answer 25

Paresthsia, numbness and weakness,
Not localised to specific nerve distribution
Aggravated by elevation or sustained use of arms or hands

Question 26

Vascular thoracic outlet syndrome?

Answer 26

Forearm fatigue within minutes of use.
Swelling and cynaosis
Collateral venous patterning over the ipsilateral shoulder, chest wall and neck.
Rarely pain, pallor and coldness (arterial involvement).
Lower BP on affected arm, diminished distal pulses.

Question 27

Long thoracic nerve comes from?

Answer 27

C 567 and supplies serratus anterior

Question 28

Compression of median nerve happens?

Answer 28

Wrist- carpal tunnel

And elbow

Question 29

Median nerve innervates?

Answer 29

L ateral 2 lumbrical
O pponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis

Question 30

Compression of median nerve results in?

Answer 30

Thenar wasting

Question 31

Carpal tunnel syndrome causes?

Answer 31

Diabetes
Pregnancy 
Hypothyroidism
Rheumatoid arthritis 
Repetitive strain

Question 32

Tinels test?

Answer 32

Percussions over any nerve and getting tingling in the distribution of that nerve

Question 33

Phalens test?

Answer 33

Flexion of wrist a minute

Question 34

Anterior interosseous nerve coming of median nerve may be compressed?

Answer 34

Between 2 heads of pronator teres

May be damaged in careless blood taking and use of screwdriver

Question 35

Anterior interosseous nerve syndrome affects?

Answer 35

Pure motor branch of median nerve

Causes weakness in flexors of interphalangeal joint of thumb (flexor pollicis longus)

Dip joints of index and middle fingers flexor digitorum profundus

Weakness of pronation

Question 36

Ulnar palsy?

Answer 36

Ulnar claw present at wrist lesion, in upper limb lesion only flexion

Question 37

Cyclists get ulnar nerve compressed at?

Answer 37

Guyons canal

Question 38

Froments sign?

Answer 38

Ulnar nerve is needed for thumb abduction,

So taking piece of paper need to keep thumb striaght

So will pinch

Question 39

C8 innervation?

Answer 39

All finger extensors by radial nerve

FDP of index and middle by median nerve

Question 40

Saturday night palsy?

Answer 40

Radial nerve affecting extensors, not much sensory disturbance

Question 41

If there is a lesion damaging axon then that affects?

Answer 41

Amplitude