NMS Flashcards
right fourth and fifth digit, a right sided foot drop and a left sided facial weakness.
diagnosis
mononeuritis multiplex
what is mononeuritis multiplex
simultaneous or sequential involvement of individual non-contiguous nerve trunks.
features of mononeuritis multiplex
acute or subacute loss of sensory and motor function of individual nerves. The pattern of involvement is asymmetric, however, as the disease progresses, deficit(s) becomes more confluent and symmetrical, making it difficult to differentiate from polyneuropathy.
predominantly motor loss of peripheral neuropathy
Guillain-Barre syndrome
porphyria
lead poisoning
hereditary sensorimotor neuropathies (HSMN) - Charcot-Marie-Tooth
chronic inflammatory demyelinating polyneuropathy (CIDP)
diphtheria
predominantly sensory loss of peripheral neuropathy
diabetes uraemia leprosy alcoholism vitamin B12 deficiency amyloidosis
alcoholic neuropathy features
secondary to both direct toxic effects and reduced absorption of B vitamins
sensory symptoms typically present prior to motor symptoms
vit B12 deficiency features
subacute combined degeneration of spinal cord
dorsal column usually affected first (joint position, vibration) prior to distal paraesthesia
what is chiari 1 malformation
herniation of the cerebellar tonsils throught the formaen magnum
disturbs the CSF - causing non-communicating hydrocephalus (uncommon) or syringomyelia (common)
- headache
what is syringomyelia
dilation of a CSF space within the spinal cord
occurs within the cervical and thoracic segments and causes compression of the spinothalamic tracts decussating in the anterior white commisure
loss of sesation of pain, temperature and non-discriminative touch
cape-like distrubution of the sensory loss
characteristic features of GBS
rapidly progressive peripheral neuropathy with lower motor neurone signs (hyporeflexia),
progressive weakness of all four limbs.
- the weakness is classically ascending i.e. the lower extremities are affected first, however it tends to affect proximal muscles earlier than the distal ones
- reflexes are reduced or absent
- sensory symptoms tend to be mild (e.g. distal paraesthesia) with very few sensory signs
- PAIN - back/leg pain in the initial stages of the illness
other features of GBS
- there may be a history of gastroenteritis
- respiratory muscle weakness
- cranial nerve involvement e.g. diplopia
- autonomic involvement: e.g. urinary retention, diarrhoea
Ix for GBS
lumbar puncture
- > rise in protein
- > normal white blood cell count (albuminocytologic dissociation) + protein
nerve condution studies may be performed
what is GBS
immune-mediated demyelination of the peripheral nervous system often triggered by an infection (classically Campylobacter jejuni).
characterised by
- paraesthesia
- weakness
- hyporeflexia
More common in men
Europe
Tx for GBS
-> intravenous immunoglobulin (IVIG) – a treatment made from donated blood that helps bring your immune system under control
plasma exchange (plasmapheresis) – an alternative to IVIG where a machine is used to filter your blood to remove the harmful substances that are attacking your nerves
treatments to reduce symptoms such as painkillers
treatments to support body functions, such as a machine to help with breathing and/or a feeding tube
what is Miller Fisher syndrome
Sx
proximal variant of GBS
antiboides angainst the ganglioside GQ1b
Sx opthalmoplegia areflexia ataxia BUT NOT WEAKNESS
RFs of GBS
- history of GI/Resp infection 1-3 weeks prior to the onset of weakness
- vaccinations
- malignancies
- pregnancy: decreases during pregnancy but increases in the months after delivery
Examination of GBS
- hypotonia
- demonstrable altered sensation or numbness
- reduced or absent reflexes
- fasciculations
- facial weakness - asymmetrical
- autonomic dysfunction - fluctuations of heart rate and arryhthmias
- respiratory muscle paralysis
DDx of GBS
barin - stroke, braisntem compression, encephalitis
spinal cord: cord compressions, polymyelitis, transverse myelitis
peripheral nerve: vasculitis, lead poisoning, porphyria
NMJ: MG, botulism
muscle: hypokalemia, polymyositis
complications of GBS
respiratory failure
persistent paralysis hypotension/hypertension thromboembolism, pneumonia, skin breakdown cardiac arryhthmia ileus aspiration pneumonia urinary retention psychiatric problems - anxiety, depression
what is vasculitic neuropathy
Patchy motor and sensory loss; pain and dysaesthesia.
Underlying primary vasculitic or rheumatological syndrome
Ix of vasculitic neuropathy
NCT may reveal clinically asymptomatic lesions.
Nerve ± muscle biopsy
acute intermittent porphyria clinical features
Ix
distal motor neuropathy, HTN, tachycardia
blood and urine analysis
diphtheria
oropharyngeal weakness at onset
pharyngeal membrane
NCT axonal neuropathy; serology
symptoms of MG
EYES
extraocular muscles
- ptosis
- pupils unaffected
BULBAR involvement - dysphagia, dysphonia, dysarthria
limb weakness
- proximal and symmetrical
resp
weaker thruout day
face weakness
limbs and trunk are less affected
no ANS involvement
muscle atrophy rare but disuse atrophy possible
abnormalities to thymus ass with autoimmune RA SLE Graves Pernicious anaemia
complications of MG
resp failure
myasthenic crisis - drooling, weak neck, slack facial muscles
Ix for MG
tensilon test
EMG
what is myasthenic crisis
Slack facial muscles Weak neck Drooling Nasal speech Generally weak Unsafe swallow
cholinergic crisis?
Looks similar to myasthenic crisis.
Excess of acetylcholinesterase inhibitors
excessive stimulation of striated muscle - flaccid paralysis
Respiratory failure
Miosis and the SLUDGE syndrome
(ie, salivation, sweating, lacrimation, urinary incontinence, diarrhea, GI upset and hypermotility, emesis) also may mark cholinergic crisis-not inevitably present
what is tensilon test
allows MG patient to move muscles normally
cautions for tensilon test
Caution – asthma, MI, bradycardia
Cardiac monitoring
normal functions of the frontal lobe
- > primary motor cortex: precentral gyrus, opposite side of the body
- > coordinating and planning complex movements
- > frontal eye field -> eye movements to the contralateral side
- > Broca’s area - motor or expressive centre of speech
- > personality, emotional expression, initiative and the ability to plan
- > inhibition of voiding of the bladder and bowel
Sx from lesions of the frontal lobe
contralateral weakness - mono/hemiparaesis and facial weakness in an UMN pattern
gait apraxia - slow, shuffling, upright and wide based
conjugate eye deviation - both eyes look towards the side of the lesion and away from the side of the weakness
focal seizures -clonic movements of the contralateral lower face, arm and leg - away from the side of the lesion
expressive dysphasia - non-fluent, hesitant speech
personality & behavioural change - social disinhibition loss of initiative and interest - inability to solve problems - impaired concentration and attention
anosmia
primitive reflexes - grasping, sucking, pouting rooting and palmomental
incontinence of urine/faeces
function of parietal lobe
primary somatosensory cortex - postcentral gyrus
language (dominant hemisphere)
use of numbers
non- dominant hemisphere - allows awareness of the body and its surroundings, appropriate movement of the body and constructional ability
visual pathways - inferior quadrantanopias
Sx from lesions of the parietal lobe
contralateral sensory loss - impairment of joint position and two point discrimination
- recognise objects by form and texture
visual disturbacnes
syndromes of the dominant parietal lobe
wernicke’s receptive ‘fluent’ dysphasia - imparied comprehension of speech and written language
gerstmann’s syndrome - cant differentiate between left and right sides of the body, impairment of calculation/writing
bilateral ideomotor adn ideational apraxia
syndromes of the non-dominant parietal lobe
contralateral sensory inattention
constructional apraxia - cant draw simple tings
dressing apraxia
topographical disorientation -> unfamiliar with normal places
function of temporal lobe
wernicke’s area - comprehension of written and spoken language
auditory and vestibular cortices
limbic system - olfactory and gustatory cortices -> medial temporal lobe - memory, learning
define pyramidal weakness
proximal weak
LOP in the extensor muscles in the arms and the flexors in the legs
UMN lesions involving ht epyramidal tract
proximal
- affecting shoulders, hips, trunk, neck and sometimes face
- characteristics - myopathy and NMJ (MG)
distal
- hands and feet
- peripheral motor neruopathy
clinical features of a UMN lesion
spasticity - clasp knife, clonus
tendon reflexes are brisk
positive babinski sign
what is tetraparaesis
weakness in all four limbs
- brainstem
- high cervical cord
- – cervical spondylosis
- – MS
- – traumatic cord lesions
types of LMN lesion
anterior horn cell
spinal nerve
plexus
peripheral nerve
characteristics of LMN lesions
- decreased tone
- focal pattern of weakness and wasting
- fasciculations
- pain and sensory disturbance - nerve roots, plexi and peripheral nerves
- reduced tendon reflexes and flexor plantar responses
focal pattern of weakness and wasting in LMN
- anterior horn
- radiculopathy
- plexopathies
- peripheral neuropathies
- NMJ disorders
- myopathies
anterior horn cell disease
- generalised weakness, wasting
- mimmin peripheral nerve lesion
radiculopathies
- weakness and wasting in the respective myotomes
plexopathies
- weakness and wasting in the plexus region
peripheral neuro
- mono - single peripheral nerve
- multiple mononeuropathies - many single nerves
- polyneuropathy - longest anxon in all nerves affected -SYMMETRICAL , GLVIE AND SOCK SENSATIONS
NMJ
- MG
myopathies - symmetrical wasting of proximal muscles
types of peripheral neuropathy
mononeuropathy - ie median nerve
multiple mononeuropathy - mononeuritis complex
polyneuropathy - vit B12, Diabetic neuropathy, drugs isoniazid
disorders of the NKJ
MG
Eaton-Lmabert
iatrogenic
features of myopathy
limb weakness bilateral and proximal
cant stand from sitting, climbing stairs
dysphagia, respiratory muscle weakness
myalgia esp after exercise
what is tremor
ivoluntary and rhythmic
- disappear during sleep
- fine - low amplitude
- coarse - high amplitude
define intention tremor
tremor that increases throughout the movement
define physiological tremor
present during waking
bilateral worse on maintaining a posture
fine and fast
define pathological tremor
occurs at rest or with movement slower coarse
asymmetrical
what is resting termor
coarse ‘pill-rolling’ tremor
- disappears during voluntary movement
- asymmetrical
what is essential tremor
coarser
AD
the tremor may worsen terminally but not throughout
temporary improvment with alchol
Mx
beta-blockers, anticholinergics, primidone
what is a kinetic tremor types
occurs during movement
cerebellar tremor - coarse often slow
absent a t rest
what is chorea
involuntary movements, abrupt and jerky
causes huntingotns SLE HIV thyroid
Mx of huntington
dopamine blocking or depleting but results in parkinsons
CAG chromosome 4
