Neuropathies

Question 1

What is syringomyelia(syrinx)

Answer 1

Syringomyelia (‘syrinx’ for short) describes a collection of cerebrospinal fluid within the spinal cord.

Question 2

Causes of syringomyelia

Answer 2

A chiari malformation(strong association)
Trauma
Tumours
Idiopathic

Question 3

Classical presentation of a syrinx

Answer 3

‘Cape-like’(neck and arms) loss of sensation to temperature but preservation of light touch, proprioception and vibration.

Other symptoms and signs include spastic weakness (predominantly of the upper limbs), paraesthesia, neuropathic pain, upgoing plantars and bowel and bladder dysfunction

Question 4

What might a syrinx cause if untreated

Answer 4

Scoliosis over a matter of years

May cause hornet’s syndrome due to compression of sympathetic chain but this is rare

Question 5

Function of CNIII

Answer 5

Eye movement (MR, IO, SR, IR)
Pupil constriction
Accomodation
Eyelid opening

Question 6

Presentation of CNIII palsy

Answer 6

ptosis
‘down and out’ eye
dilated, fixed pupil

Question 7

Function of CNIV

Answer 7

Eye movement (SO)

Question 8

Presentation of CNIV palsy

Answer 8

Palsy results in defective downward gaze → vertical diplopia

Question 9

Function of CNV

Answer 9

Facial sensation

Mastication

Question 10

Presentation of trigeminal nerve lesions

Answer 10

trigeminal neuralgia
loss of corneal reflex (afferent)
loss of facial sensation
paralysis of mastication muscles
deviation of jaw to weak side

Question 11

Function of CNVI

Answer 11

Eye movement (LR)

Question 12

Presentation of CNVI palsy

Answer 12

Palsy results in defective abduction → horizontal diplopia

Question 13

Function of CNVII

Answer 13

Facial movement
Taste (anterior 2/3rds of tongue)
Lacrimation
Salivation

Question 14

Presentation of CNVII lesions

Answer 14

flaccid paralysis of upper + lower face
loss of corneal reflex (efferent)
loss of taste
hyperacusis

Question 15

Function of CNVIII

Answer 15

Hearing

Balance

Question 16

Presentation of CNVIII palsy

Answer 16

Hearing loss
Vertigo, nystagmus
Acoustic neuromas are Schwann cell tumours of the cochlear nerve

Question 17

Function of CNIX

Answer 17

Taste (posterior 1/3rd of tongue)
Salivation
Swallowing
Mediates input from carotid body & sinus

Question 18

Presentation of CNIX lesions

Answer 18

Lesions may result in;
hypersensitive carotid sinus reflex
loss of gag reflex (afferent)

Question 19

Function of CNX

Answer 19

Phonation
Swallowing
Innervates viscera

Question 20

Presentation of CNX lesions

Answer 20

Lesions may result in;
uvula deviates away from site of lesion
loss of gag reflex (efferent)

Question 21

Function of CNXI

Answer 21

Head and shoulder movement

Question 22

Presentation of CNXI lesions

Answer 22

Lesions may result in;

weakness turning head to contralateral side

Question 23

Function of CNXII

Answer 23

Tongue movement

Question 24

Presentation of CNXII palsy

Answer 24

Tongue deviates towards side of lesion

Question 25

Corneal reflex - afferent and efferent limb

Answer 25

Aff - Ophthalmic(v1) | Eff - Facial

Question 26

Jaw jerk reflex - aff and eff limb

Answer 26

Aff - Mandibular nerve(V3) | Eff - Mandibular nerve(V3)

Question 27

Gag reflex - nerve limbs

Answer 27

Aff - IX | Eff - X

Question 28

Carotid sinus reflex - nerve limbs

Answer 28

Aff - IX | Eff - X

Question 29

Pupillary light reflex - nerve limbs

Answer 29

Aff - II | Eff - III

Question 30

Lacrimation - nerve limbs

Answer 30

Aff - V1 | Eff - VII

Question 31

What is a benign essential tremor

Answer 31

Associated with older age | Characterised by fine tremor affecting all voluntary muscles(most notable in hands)

Question 32

Features of benign essential tremor

Answer 32

``` Fine tremor Symmetrical More prominent on voluntary movement Worse when tired, stressed or after caffeine Improved by alcohol Absent during sleep ```

Question 33

Causes of tremor

Answer 33

``` Parkinson’s disease Multiple sclerosis Huntington’s Chorea Hyperthyroidism Fever Medications (e.g. antipsychotics) ```

Question 34

Mx of benign essential tremor

Answer 34

Does not need treatment if not causing functional or psychological problems Propranolol (a non-selective beta blocker) Primidone (a barbiturate anti-epileptic medication)

Question 35

Typical features of neuropathic pain

Answer 35

``` Burning Tingling Pins and needles Electric shocks Loss of sensation to touch of the affected area ```

Question 36

Questionnaire used to assess neuropathic pain

Answer 36

DN4 questionnaire They are then scored out of 10 for their pain. A score of 4 or more indicates neuropathic pain.

Question 37

Mx of neuropathic pain

Answer 37

Amitriptyline Duloxetine Gabapentin Pregabalin

Question 38

1st line mx of neuropathic pain in trigeminal neuralgia

Answer 38

Carbamazepine

Question 39

Other options for mx of neuropathic pain

Answer 39

Tramadol ONLY as a rescue for short term control of flares Capsaicin cream (chilli pepper cream) for localised areas of pain Physiotherapy Psychological input

Question 40

What is complex regional pain syndrome

Answer 40

Areas are affected by abnormal nerve functioning causing neuropathic pain and abnormal sensations. It is usually isolated to one limb. Often it is triggered by an injury to the area.

Question 41

Presentation of complex regional pain syndrome

Answer 41

The area can become very painful and hypersensitive even to simple inputs such as wearing clothing. It can also intermittently swell, change colour, change temperature, flush with blood and have abnormal sweating.

Question 42

Mx of complex regional pain syndrome

Answer 42

Treatment is often guided by a pain specialist and is similar to other neuropathic pain.

Question 43

Effects of radial nerve damage

Answer 43

Wrist drop Sensory loss to small area between dorsal aspect of the 1st and 2nd metacarpals paralysis of triceps

Question 44

Effects of median nerve damage

Answer 44

paralysis and wasting of thenar eminence muscles and opponens pollicis (ape hand deformity) sensory loss to palmar aspect of lateral (radial) 2 ½ fingers unable to pronate forearm weak wrist flexion ulnar deviation of wrist

Question 45

Median nerve root

Answer 45

median nerve is formed by the union of a lateral and medial root respectively from the lateral (C5,6,7) and medial (C8 and T1)

Question 46

Radial nerve root

Answer 46

C5-T1

Question 47

Common peroneal nerve root

Answer 47

L4-S2

Question 48

Features of common perineal nerve lesion

Answer 48

Foot drop weakness of foot dorsiflexion weakness of foot eversion weakness of extensor hallucis longus sensory loss over the dorsum of the foot and the lower lateral part of the leg wasting of the anterior tibial and peroneal muscles