Prof Uma Flashcards
signs to look for to differentiate between UMN and LMN?
Wasting, tone, reflexes, clonus, Babinski
Bilateral UL and LL weakness -> next step?
UMN or LMN?
Bilateral UL and LL weakness -> LMN pattern of weakness -> what next?
Distal or proximal weakness
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> what next?
Sensation normal or abnormal?
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> normal sensation
Potential causes:
1) motor neuron disease: pure motor atrophy, polio
2) pure motor peripheral neuropathy: MMN
3) distal myopathy: myotonic dystrophy, inclusion body myositis
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> sensation abnormal -> what next?
Glove and stocking numbness
Vs
Patchy numbness
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> sensation abnormal -> glove and stocking numbness
Causes?
Peripheral neuropathy
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> sensation abnormal -> patchy numbness
Potential causes?
In distribution of peripheral nerve:
Mononeuritis multiplex
Mono-neuropathies
Multiple mononeuropathies: Vasculitic neuropathy, Leprosy, multiple entrapment neuropathy
Dermatomal:
Radiculopathy
Bilateral UL and LL weakness -> LMN pattern of weakness -> proximal weakness -> what next?
Sensation normal or not?
Bilateral UL and LL weakness -> LMN pattern of weakness -> proximal weakness -> sensation normal
Potential causes?
1) myopathy
2) myasthenia Gravis (fatiguable, bulbar and ocular weakness)
3) motor neuron disease: spinal muscular atrophy, progressive muscular atrophy. Polio (fasciculations, bulbar weakness)
Bilateral UL and LL weakness -> LMN pattern of weakness -> proximal weakness -> sensation abnormal
Potential causes?
If UL is normal, Lumbosacro plexo/radiculopathy
If LL normal or unilateral, c5-6 radiculopathy or brachial plexopathy
If UL and LL affected: GBS/ CIDP
Causes of myopathies?
Congenital/Inherited: dystrophy (Myotonic dystrophy, Fascioscapulohumeral dystrophy, Becker’s, limb-girdle muscular dystrophy)
Metabolic/ Endocrine: hypo/hyperthyroidism, Cushing’s syndrome, Vit D Deficiency
Neoplastic/ paraneoplastic: dermatomyositis
Inflammatory/ infectious: polymyositis, dermatomyositis, myositis
Human activity (Iatrogenic/ toxin/ trauma): Drugs-statin, fenofibrate, colchicine
Causes of diffuse polyneuropathy?
Congenital: Charcot Marie tooth, amyloidosis
Metabolic/ endocrine: DM, b12 deficiency, renal failure, hypothyroidism
Neoplastic/ paraneoplastic: anti Hu antibody associated sensory neuropathy
Inflammatory/ infectious: GBS/ CIDP, sjogrens, HIV
Drugs/ iatrogenic/ trauma: isoniazid, vincristine, cisplatin, alcohol/ lead
If multiple mononeuropathy in UL and LL ? Causes
Vasculitis neuropathy
Leprosy
Multiple entrapment neuropathy
How to differentiate between L5 radiculopathy, sciatic neuropathy and peroneal neuropathy?
All 3 have:
Weak Ankle dorsiflexion, eversion
Numbness on dorsum of foot
Both sciatic neuropathy and L5 radiculopathy:
+ Weak inversion
Sciatic neuropathy alone:
Ankle reflex absent or weak
Weak ankle plantarflexion
Numb sole
L5 radiculopathy alone;
Weak hip abduction, internal rotation and extension
How to differentiate between C8 radiculopathy and ulnar mononeuropathy?
Both have:
Weak finger abduction and flexion
Weak thumb adduction
Numb 5th digit
Ulnar neuropathy:
Split ring finger sensory loss
froments sign +
C8 radiculopathy:
Weak thumb abduction, flexion
Weak finger extension at MCPJ
How to differentiate between C7 radiculopathy and radial mononeuropathy?
Both:
- triceps reflex weak/ absent
- weak elbow extension, wrist extension, finger MCPJ extension
- numb dorsum of hand
Radial mononeuropathy:
Brachioradialis bulk and strength affected
C7 radiculopathy:
+/- mild weakness of forearm pronation
Finger extension at interphalangeal joint weak
How to differentiate between femoral neuropathy vs L4 radiculopathy?
Both have:
- weak knee reflex
- weak knee extension
- numb medial shin
Femoral neuropathy only:
Weak hip flexion
L4 radiculopathy:
Weak hip adduction
Adductor reflex affected
Bilateral LL weakness -> UMN pattern weakness -> what next?
Assess sensation
Bilateral LL weakness -> UMN pattern weakness -> normal sensation
Causes?
Motor neuron disease: look for wasted tongue with fasciculations, mixture of UMN/LMN signs
Subcortical:
Binswanger disease, multiple strokes
Cortical: parasagittal lesions (meningioma)
Hereditary spastic paraplegia
Bilateral LL weakness -> UMN pattern weakness -> abnormal sensation
Causes
Means pathology at spinal cord
-> use reflex and power to localise segment of spinal cord involved
Glove and stocking:
Chronic cervical myelopathy
Medical myelopathy
Sensory level:
Myelopathy/ myelitis (fairly acute)
Approach to cranial neuropathy?
4 different classifications
ie. once you notice cranial nerve pathology, work along this pathway to neurolocalise
Brainstem lesions: check for pronator drift, dysdiadochokinesia, babinski normal
Cranial nerve clubs
Meningeal and skull base disease e.g. TB meningitis, NPC: signs of meningism, neck stiffness. any epistaxis? any cervical lymphadenopathy
Peripheral neuropathy: GBS and its variants
Cranial neuropathy due to brainstem lesion
Causes
Except cranial nerves 1 & 2 which originate from cerebrum, CN 3-12 originate from brainstem
Midbrain: 3, 4 (look for drowsiness, vertical gaze abnormalities, cerebellar and pyramidal signs)
Pons: 5, 6, 7, 8 (look for horizontal gaze abnormalities, pyramidal, cerebellar signs, drowsiness
Medulla: 9-12
Look for horners, pyramidal, cerebellar signs, drowsiness
Cranial neuropathies
Cranial nerve “clubs”
Cavernous sinus
Orbital apex
Cerebellopontine angle
Jugular foramen
Cranial neuropathies
Base of skull and meningeal disease
Acute/ chronic meningitis: TB, carcinomatous
Base of skull pathology: NPC, radiation
Cranial neuropathies
Peripheral neuropathy GBS And its variants
GBS, miller fisher syndrome
Areflexia
Weakness
Numbness
Incoordination
Pt has dysarthria and dysphagia
Approach to cranial nerve exam
Muscle: eg myotonic dystrophy -> signs of diffuse myopathy
NMJ: not much findings in the “mouth”. fatiguable ptosis, ophthalmoplegia
Cranial nerves: asymmetric tongue (can be symmetric for bilateral CN 12), palatal deficits, dysarthria (speech abnormal), check CN XI (trapezius, SCM)
Anterior horn cell:
Wasting and fasciculations of tongue
Mixture of UMN and LMN eg brisk jaw jerk
Pseudobulbar palsy: brisk jaw jerk, no atrophy/ fasciculations
Ptosis -> unilateral -> what to differentiate between
- Check pupil next!!!
Horners? (Miosis)
Involvement of CN III? (dilated pupil)
- EOM affected?
- Fatiguability -> Myasthenia gravis?
Muscle: local orbit infiltration/ pathology?
Causes of CN III palsy?
Isolated CN III palsy
Cavernous sinus/ superior orbital fissure/ orbital apex
Midbrain: 3+4 with long tract/ cerebellar signs
GBS/MFS
Causes of horners syndrome: different areas that may be affected
Carotid artery/ neck
Lung apex
T1 spine
Lateral medulla (look for pyramidal/cerebellar signs + horners), AICA (lat pontine)
Bilateral ptosis causes
Myopathy eg CPEO
Myotonic dystrophy
Local infiltration
Myasthenia gravis
Bilateral CN III
- midbrain nuclear III
- GBS/ MFS
Blurring of vision -> what to ask next?
Monocular or binocular ?
Binocular visual loss-> what to check next?
Visual fields
Eg
Bitemporal
Homonymous hemianopia
Binocular visual loss -> bitemporal hemianopia on VF exam?
*remains w either eye closed
Chiasmal lesion
May have to look for endocrinopathy from pituitary lesion
Visual blurring ->binocular vision loss-> homonymous VF loss
How to neurolocalise
*should remain w either eye closed
Isolated: occipital cortex
Assoc other hemispheric signs: parietal and or temporal lobes
-> e.g right hemispheric: neglect, constructional dyspraxia
Left: dysphasia, neglect
Visual blurring-> binocular vision affected -> diplopia on examination?
Eye movement pathology
- blurring disappears with either eye closed
Visual blurring-> binocular loss-> central VF affected
Normal pupils: bilateral occipital lobe lesion (cortical blindness)
Pupils affected: bilateral optic neuropathy
Causes of diplopia
Muscle: eg thyroid eye disease, CPEO
NM junction eg myasthenia gravis
Nerve- Cranial nerve III, IV and VI
Brainstem- eg INO, skew deviation
(subcortical and cortical pathology
does not cause diplopia)
Visual blurring -> monocular -> what next?
Correctable w glasses?
RAPD present?
If correctable w glasses, no RAPD-> problem w refractory media eg myopia, cataracts
If not correctable, RAPD present-> optic neuropathy or massive retinal problem eg CRAO, CRVO
Causes of optic neuropathy
Congenital: eg Leber’s optic atrophy, Fredrich’s ataxia
Metabolic-endocrine: B12 deficiency, malnutrition, complications of thyroid eye disease
Vascular/ degenerative:
(stroke of the lI nerve-painless) AION, PION;
arteritic AION (temporal arteritis);
under degenerative-glaucoma
Inflammatory- infectious: optic neuritis in MS and NMO (painful), anti-MOG positive, sarcoidosis, Ig G4 disease;
Orbital cellulitis, Bacterial meningitis, Syphilis, Lyme disease, TB, HIV, CMV, Cryptococcal
Neoplastic: optic nerve glioma, meningioma, mets to orbits.
Drugs/iatrogenic: traumatic, radiation, methanol, ethambutol
Red flags of headache to suggest secondary cause
- Focal neurological deficit
- Obtundation of sensorium
- Raised intracranial pressure symptoms and signs
- Constitutional symptoms
- Character: thunderclap, new onset nocturnal headaches, persistent/prolonged/progressive, change in character, new headache in older persons
Parkinson’s plus syndromes : what to examine for
Asymmetry
# Vertical saccadic eye movements
# Cerebellar signs
# Postural hypotension, urinary incontinence, impotence
Drug history, family history, liver disease
Falls, Autonomic symptoms
Hallucinations
Hx of hypoxic cerebral injury/ encephalitis/osmotic
demyelination
Mental state examination for cognitive impairment
Response to madopar
Parkinsonism diagnosis : what is important to assess for after?
- Severity
- Disability and handicap -> get MDT to help assess and alleviate
- Assess for complications e.g. dyskinesia, depression, behaviourial problems, osteoporosis, falls, recurrent infection; and put in place pre-emptive/pro-active management and surveillance plan
Causes of cerebellar disorders
Congenital: spinocerebellar ataxia, AChiari malformation, Ataxia telengectasia, wilson disease
Metabolic/endocrine: Hypothyroidism, Wernicke’s
Inflammatory/Infectious: MS/ADEM, anti-MOG , (NMO from medullary lesions) anti-GAD, (? anti TPO)
Varicella, Listeria, abscess, TB, variant CJD
Neoplastic/paraneoplastic: primary/secondary tumour in cerebellum or CPA, Anti-Hu/Yo
Vascular/degenerative: Strokes, PRES, Multiple system atrophy
Toxic/iatrogenic: alcohol, phenytoin, lithium
General principles of how to investigate a patient?
• Confirm diagnosis
• Investigations to look for co-morbid
factors/risk factors/associated
disease and complications of the
illness
• Investigations to assess general
condition
General principles of how to manage a patient?
• Specific treatment
• Manage for co-morbid factors/
associated disease and complications of the illness
• Management of disability and handicap
Management of status migrainosus
1) IV maxolon 10mg tds (remember oculgyric crisis), IV sodium valproate
2) Ketorolac 30mg i/m OR diclofenac 75mg i/m (remember contraindiactions to NSAIDS)
Place patient in DARK ROOM; consider IV FLUIDS for hydration
What is athetosis
continuous stream of slow, flowing, writhing involuntary movements that prevent maintenance of a stable posture. Usually affects the hands and feet
What is chorea
repetitive, brief, irregular, somewhat rapid involuntary movements that start in one part of the body and move abruptly, unpredictably, and often continuously to another part.
It typically involves the hands, feet, and face.
The movements may merge imperceptibly into purposeful or semipurposeful acts
What is dystonia
sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both.
Tends to be sustained at the peak of the movement, can progress to prolonged abnormal postures.
What is myoclonus
sudden, brief, jerky, and shock-like involuntary movements involving face, trunk, and extremities.
What is balismus
rapid, involuntary, non-stereotypical, non- purposeful, relatively more violent flinging movement, that involves the proximal muscle group more than distal
History in involuntary movements?
- Time course/ Onset
- Unilateral or bilateral?
- Do specific actions provoke the movement?
- Do the movements occur during sleep?
- Can the movements be suppressed?
- Are there aggravating or alleviating factors?
- Infections and toxin exposures, including alcohol
- Drug history
- Birth history and developmental milestones
Involuntary movements:
Physical examination
- Nature of involuntary movements
- Rhythmic vs. Arrhythmic
- Sustained vs. Nonsustained
- Paroxysmal vs. Nonparoxysmal
- Slow vs. Fast
- Amplitude
- At rest vs. Action
- Supressibility
- Finger and rapid alternating movements
- Affected body parts
- Detailed neurological examination
- Cognitive assessment
Causes of rhythmic involuntary movements
• Tremor
• Dystonic tremor
• Myoclonus
• Periodic movements of sleep
• Tardive dyskinesia
what is kennedy’s disease?
bulbospinal muscular atrophy
associated androgen defect from the androgen receptor gene (trinucleotide repeat) mutation
features of kennedy’s disease (bulbospinal muscular atrophy)?
- Proximal Weakness usually LL > UL
- Gynaecomastia may be asymmetric
- tongue: weakness, atrophy, fasciculations
- Bulbar dysfunction: dysphagia, dysarthria, master weakness
- Slowly progressive: over decades
- Cramps in 50%
Tendon reflexes: absent or reduced
sensory: often subclinical changes
- Vibration may be reduced legs > arms
NO UMN signs
systemic:
Androgen insensitivity related: gynaecomastia, reduced fertility, testicular trophy, erectile dysfunction
Investigations in Kennedy’s disease (bulbospinal muscular atrophy)
Nerve conduction studies: reduced amplitude
EMG
Genetic studies
Serum:
- CK high
- Serum oestradiol, gonadotropin elevated
- Lipid disorders: Type II, IV hyperlipoproteinaemia, hypobetalipoproteinaemia
Management of ALS?
Riluzole 50mg BD
Aggressive physical and speech therapy
Monitor for nocturnal hypoventilation e.g. sleep study and institute early NIV
Address psychosocial issues and depression proactively and pre-emptively, consider SSRI
If dysphagia severe consider early PEG insertion
Continue w normal work/family/social activities as much as possible
At some point, discuss EOL goals and wishes
what is hirayama disease?
Monomelic amyotrophy (MMA), also known as Hirayama disease, is a sporadic juvenile muscular atrophy in the distal upper extremities, which predominantly affects the lower cervical cord (e.g., seventh and eighth cervical vertebra levels)
usually weakness and atrophy of unilateral or bilateral hand muscles, commonly encountered in young Asian males.
-> LMN, distal weakness, no sensory loss
treatment of multifocal motor neuropathy?
IVIG
severe bulbar weakness and facial weakness but not much eye involvement - what version of MG?
MUSK +ve Myasthenia Gravis
What is MND progressive muscular atrophy subtype?
Involves only the lower motor neurons (degeneration of anterior horn cells), causing progressive weakness and atrophy
LMN weakness, no sensory involvement
preserved deep tendon reflexes
- but take note 70% can eventually demonstrate signs of UMN degeneration
Investigations for motor neuron disease?
For diagnosis:
- Clinical history and examination of MND may be sufficient for diagnosis with classical bulbar weakness, wasting and fasciculations (including of the tongue).
- less clear-cut cases can be supported by a modest rise in CK and EMG changes consistent with denervation.
- MRI of the spine/ brainstem is often performed to rule out multi- level compressive/ degenerative disease as a mimic of motor neurone disease (MND) (e.g. mixed upper and lower motor neurone signs could be due to multilevel radiculo- myelopathy).
- Increasingly, genetic testing is used first line.
For complications:
E.g, CXR for recurrent aspiration pneumonia
For general health
Diagnosis of MND subtype progressive muscular atrophy?
Diagnosis of exclusion
Other diagnoses need to be ruled out eg multifocal motor neuropathy or spinal muscular atrophy.
Tests used in the diagnostic process include MRI, clinical examination, and EMG.
EMG usually show denervation in most affected body parts, and in some unaffected parts too.
What is multifocal motor neuropathy?
A pure motor neuropathy
- affecting individual nerves
- usually asymmetric involvement
- no upper motor neuron (UMN) signs
- no sensory deficits
- thought to be immune mediated
- NCS: evidence of conduction block
A long, thin face with hollow temples, drooping eyelids and, in men, balding in the front, is typical in myotonic dystrophy.
what is myotonic dystrophy?
an autosomal dominant
chronic
slowly progressing
highly variable
inherited multi systemic disease
trinucleotide repeat disorder
genetic anticipation
-> so subsequent generations may display an earlier onset and great severity of the condition
characteristic neurology pattern of myotonic dystrophy?
LMN
-> distal weakness
-> no sensory involvement
signs:
muscle wasting (especially distal)
myopathic facies with frontal balding, ptosis
myotonia with difficulty in releasing handgrip
Bilateral UL and LL weakness -> LMN pattern of weakness -> distal weakness -> normal sensation
what additional examination to differentiate between likely causes?
- open and close hands: difficulty in releasing handgrip with myotonia -> myotonic dystrophy
- percussion myotonia
how to differentiate between motor neuron disease vs multifocal motor neuropathy
- motor neuron disease (usually segmental pattern e.g. C7/8) + look for other signs of ALS (examine tongue!)
- multifocal motor neuropathy is usually a peripheral nerve distribution (e.g ulnar/ median)
diagnostic hallmark of multifocal motor neuropathy?
multiple motor conduction blocks
what antibody is implicated in multifocal motor neuropathy?
antibodies to ganglioside GM1
reported in 20%-80% of patients
what are some other non - neurological complications of myotonic dystrophy?
cataracts
endocrine problems:
T2DM
Thyroid dysfunction
testicular atrophy
cardiac problems:
cardiomyopathy
cardiac conduction defects (heart block)
OSA
what muscles are most often affected in myotonic dystrophy type 1?
the facial muscles
levator palpebrae superioris
temporalis
sternocleidomastoids
distal muscles of the forearm
hand intrinsic muscles
ankle dorsiflexors
diagnostic investigations for myotonic dystrophy
genetic testing
NCS, EMG which demonstate myotonia
investigations for complications in myotonic dystrophy
- regular ophthalmology review: screen for cataracts
- regular ECG +/- 24h holter to monitor for heart block
- echocardiogram: may be yearly to look for cardiomyopathy
- sleep study for OSA, pulmonary function tests
- measure TFT, HbA1c
management of complications in myotonic dystrophy?
cardiac: pacemaker, ICD
OSA: CPAP
DM, thyroid disorder treatment
management of myotonic dystrophy?
Genetic counselling: subsequent generations may see more severe disease due to genetic anticipation
PTOT
speech therapy if there are swallowing impairment issues
for myotonia:
sodium channel blockers, TCAs, benzodiazepines
what special examination to do when suspecting myotonic dystrophy?
- grip myotonia (close hand tight then open hand quickly)
- percussion myotonia (percuss over thenar eminence)
what is Motor neuron disease?
progressive neuronal degenerative disease leading to severe disability and death
(involves degeneration of both UMN and LMN)
what are the different clinical subtypes of MND?
- Most common: Amyotrophic lateral sclerosis (ALS)
- 5-10% are familial, mostly of autosomal dominant inheritance
- mixed UMN and LMN involvement of bulbar structures/ UL and LL - Progressive bulbar palsy
- dominant bulbar weakness
- 50% mortality within 30 months of symptom onset - Primary lateral sclerosis
- exclusive UMN involvement
- tends to progress more slowly - Progressive muscular atrophy
- only LMN
structures involved in Amyotrophic Lateral Sclerosis?
Upper and lower motor neurone involvement of bulbar structures (nerves, tracts and muscles [including those of the tongue, pharynx and larynx] connected to the medulla) +
upper and lower limbs.
-> Must think about in patients with dysphagia, dysarthria, weakness
Management of motor neuron disease?
treating the condition: supportive
riluzole has been demonstrated to extend life by about 2- 3 months (delaying requirement for ventilation +/- trache)
NIV for support of breathing
MDT approach:
- Speech therapy to assess and manage bulbar dysfunction + discussions around altered diet/ feeding routes e.g PEG
- PT and OT to extend useful motor function with appropriate exercises and walking aids
- Respiratory and palliative care physicians facilitating decisions regarding ventilatory support
Symptom control:
baclofen for spasticity
antimuscarinics for excessive saliva
benzodiazepines for breathlessness
Advanced directives and end of life care
diagnosis of motor neuron disease
may be diagnosed from clinical history and examination by a specialist
- should be a diagnosis of exclusion (exclude reversible causes e.g. structural lesion)
causes of peripheral neuropathy?
causes are rearranged depending on patient characteristics and history
congenital/ inherited: Charcot Marie Tooth, Amyloidosis
Metabolic/ endocrine: DM, Chronic renal failure, B12 deficiency, hypothyroidism
Neoplastic: anti-Hu antibody associated sensory neuropathy (more sensory)
Inflammatory/ Infectious: GBS/ CIDP, Sjogren’s syndrome, HIV
Human activity: drugs: cisplatin, vincristine, taxol, thalidomide, pyridoxine, isoniazid (S>M), chloroquine, toxins (alcohol, lead)
Charcot Marie Tooth
aka
Hereditary motor and sensory neuropathy
what is Charcot Marie Tooth disease?
autosomal dominant condition
- causing mixed motor and sensory neuropathy
- typically with deformities such as pes cavus
pathophysiology of charcot marie tooth disease?
affects peripheral nerves! both sensory and motor nerves are affected
usually hereditary, many genes are implicated
usually demyelinating or axonal
most common subtypes of charcot marie tooth
CMT 1
most commonly due to duplication of the PMP22 gene on chromosome 17
- demyelinating
- NCS will show slowed conduction
CMT2: axonal
- most commonly due to mitofusin 2 mutations
- NCS will show reduced amplitudes
CMT type 4: autosomal recessive
CMT X: X linked mutation (Males > females affected), can be axonal or demyelinating
features of charcot marie tooth disease?
progressive distal weakness that extends proximally
- LMN pattern: wasting, hyporeflexia
-> may lead to foot drop and high stepping gait
-> pes cavus and hemmer toes
-> clawing of hands
-> inverted champagne bottle appearance due to wasting of calf muscle
-> palpable thickened nerves (elbow, tibia, thigh)
investigations of charcot marie tooth disease?
family history and genetic testing
nerve conduction studies:
reduced velocity -> demyelinating
reduced amplitude -> axonal loss
nerve biopsy:
onion peel appearance. repeated demyelination and remyelination of enlarged nerve fibres
rule out other causes of peripheral neuropathy:
e.g. screen for DM HbA1c, B12 deficiency
LP to look for evidence of CIDP
management of charcot marie tooth disease?
genetic counselling
to treat the disease: supportive, no cure
MDT: PT OT podiatry/ orthotics, e.g. for walking aids, braces
orthopaedic surgery - may be required to stabilize foot/ joint
peripheral neuropathy:
which causes mainly cause axonal loss and what is the significance of this?
axonal loss
means usually affect sensory/ autonomic nerve fibres first (autonomic fibres are unmyelinated, and sensory nerves have unmyelinated sections unlike motor nerves)
DM
Alcohol
B12 deficiency
chemotherapy
hypothyroidism
HIV
more rare
critical illness polyneuropathy
uraemic polyneuropathy
paraproteinaemia
paraneoplastic
-> would cause more sensory symptoms than motor (ie. parasthesiaes/ numbness)
peripheral neuropathy:
which causes mainly cause demyelination and what is the significance of this?
demyelination means that motor neurons tend to be affected first
causes:
GBS
CIDP
Charcot marie tooth
Ix in peripheral neuropathy?
Blood tests: screen for reversible (and diagnose) underlying cause
HbA1c
TFT
B12
Renal panel (urea)
Lumbar puncture: may be useful if considering GBS/ CIDP
Nerve conduction studies: can be useful to determine if polyneuropathy due to axonal (reduced amplitude) or demyelinating (slower conduction) injury
pathophysiology of Guillain Barre syndrome?
acute inflammatory demyelinating polyneuropathy
usually triggered by infection e.g. campylobacter jejuni, EBV/ CMV
due to molecular mimicry -> antibodies against these infectious agents cross react with gangliosides displayed on nerve cells -> immune mediated attack on either schwann cell or axon
typical history of guillain barre syndrome?
preceding infectious illness followed by onset of distal sensory loss 1-2 weeks later (symptoms usually peak within 2-4 wks followed by gradual recovery)
-> sensory loss may progress and spread proximally
motor involvemeny may occur
Ix of guillain barre syndrome
to diagnose:
clinical diagnosis
supported by
- nerve conduction studies: slowed conduction velocities with prolonged F wave and distal latencies (demyelination)
- LP: raised protein, normal cell count
- FVC: <20ml/kg or NIF <-20 to 30-> may require ventilation
management of Guillain Barre syndrome
of the disease:
IVIG
plasma exchange
management of complications:
respiratory failure: ventilatory support in ICU
autonomic instability: may need inotropic support
impaired swallowing: tube feeding
PTOT
poor prognostic factors of Guillain Barre Syndrome?
- IgG and GM1 ganglioside antibodies
- axonal involvement
- advanced age
which antibodies may follow CMV infection producing guillain barre syndrome
anti-GM2 ganglioside antibodies
-> associated with a predominantly sensory neuropathy
prognosis in guillain barre syndrome?
80% recover
15% some residual neurological disability
5% die
Complications usually arise from respiratory failure, cardiac dysrhythmias and labile BP
what is miller fisher syndrome?
Triad of ataxia, areflexia and ophthalmoplegia causing a proximal/ descending pattern of nerve involvement.
what antibodies are implicated in miller fisher syndrome
IgG anti-GQ1b ganglioside antibodies are found in 90– 95% of patients.
what is CIDP?
relapsing and remitting nerve dysfunction causing sensorimotor disturbance (peripheral neuropathy pattern)
cause is not fully understood. felt to be immune mediated
no clear infectious trigger
ix of Chronic inflammatory demyelinating polyneuropathy?
diagnosis requires evidence from NCS of demyelination in at least 2 nerves
LP: CSF protein level may be high, WCC normal
Nerve roots may be enlarged or enhance with gadolinium on MRI.
management of chronic inflammatory demyelinating polyneuropathy?
- steroids
- IVIG
- cyclophosphamide
- plasma exchange
relation between CIDP and multifocal motor neuropathy?
multifocal motor neuropathy is a variant of CIDP
- which affects men > women
- associated with anti-GM1 ganglioside antibodies
paraneoplastic cause of peripheral neuropathy?
anti-Hu antibody may cause sensory peripheral neuropathy (usually axonal loss)
anti-hu associated sensory neuropathy linked to which most common cancer?
limited stage small cell lung cancer
causes of mononeuritis multiplex?
Common:
Connective tissue diseases: SLE, rheumatoid arthritis, Sjogrens (less common)
Vasculitis: polyarteritis nodosa, granulomatosis with polyangiitis (less common)
Diabetes mellitus
Less common:
amyloidosis
cryoglobulinaemia
infections; HIV, Lyme disease, Leprosy
Sarcoidosis
investigations to perform for any nerve disease (poly or mononeuropathies)?
Nerve conduction studies:
helpful in delineating type of nerve damage e.g. axonal or demyelinating
EMG: useful in motor neuropathy as muscle will demonstrate change secondary to denervation or conduction block
nerve biopsy: reserved for when other diagnostic options have failed
- usually from a sensory nerve identifiably and recently affected, or from a nerve that will not cause major disability when damaged, such as the sural nerve
imaging:
- to identify focal nerve damage, particularly in sites less amenable to neurophysiology or biopsy such as the brachial plexus
investigations for mononeuritis multiplex?
usually nerve conduction studies
if necessary, nerve biopsy
management of mononeuritis multiplex?
treat the underlying cause
features of leprosy
- skin: usually hypoaesthetic well demarcated and hypopigmented lesions
- may see collapsed nasal bridge
- thickened peripheral nerves
- crippling of hands/feet due to paralysis
management of leprosy?
multi drug therapy for 1-2 years
usually with rifampicin, dapsone, clofazimine
in a patient with LMN pattern of proximal weakness, and normal sensation, what examination would you perform to differentiate between the likely causes?
need to differentiate between myopathy, myasthenia gravis and Motor neuron disease
look for signs of MG:
fatiguability -> examine eyes for ptosis.
involvement of bulbar, ocular weakness (complex ophthalmoplegia)
signs of MND:
examine the tongue for wasting/ fasciculations
examine for fasciculations in exposed muscle groups
mixed UMN/LMN signs
bulbar weakness
looking for myopathy bit more tricky and likely need to work through check list of potential causes of myopathy to look for signs
features of myasthenia gravis?
Typified by ‘fatigable’ muscle weakness:
◆ Muscle weakness becomes more prominent with repetitive muscle contraction.
◆ Symptoms become more obvious as the day progresses.
May be localised:
◆ Commonly to eyes, bulbar muscles or both (oculobulbar myasthenia).
◆ Causes fatigable ophthalmoplegia (resulting in diplopia), ptosis, dysarthria and dysphagia.
◆ Weight loss is a common sequel of bulbar involvement
May be generalised:
◆ Affecting limb muscles and leading to respiratory compromise.
◆ May cause ‘myasthenic crisis’ where emergent respiratory support is required.
pathophysiology of myasthenia gravis
autoimmune disorder
- igG antibodies against the acetylcholine receptor
- 20-25% of patients are anti-AChR antibody negative
- >50% of seroneg MG patients have IgG antibodies to muscle specific kinase (MusK)
treatment of myasthenia gravis?
acetylcholinesterase inhibitor e.g. pyridostigmine
-> cholinergic side effects such as diarrhoea may be managed with propantheline bromide
immunomodulation to reduce AChR antibody production
-> low dose steroids prednisolone if mild disease
-> may have to add on other steroid sparing agents in more severe disease e.g. methotrexate, azthioprine, MMF, ciclosporin, rituximab
Acute severe myasthenic crises:
IVIG is mainstay of treatment.
Plasmapheresis has not been found to be superior to IVIG
IX of myasthenia gravis?
Bedside:
monitor Forced vital capacity and negative inspiratory force
ice pack test
To diagnose:
blood tests for Anti-AChR and anti-MuSK Ab
electrodiagnostics: single fibre EMG with repetitive nerve stimulation test
Screen for complications e.g. thymoma
Imaging:
CT chest to screen for thymoma
MRI of the cranium and orbits may also be performed to exclude compressive and inflammatory lesions of the cranial nerves and ocular muscles.
Treatment planning
e.g. if planning immunosuppression
may need to screen for Hep B/ Hep C/ HIV
features of Lambert-Eaton myasthenic syndrome?
rare autoimmune disorder
antibodies against VGCC impairing release of acetylcholine by the presynaptic terminal of the NMJ
- typically proximal weakness and fatigue
- weakness is often relieved temporarily after exertion (improvement of power on repeated hand grip)
- associated with underlying malignancy in 60% most commonly SCLC
- assoc with disruption of autonomic nervous system function
treatment of lambert eaton myasthenic syndrome?
treatment of underlying malignancy if present often relieves symptoms
other treatments used include steroids, azathioprine, IVIG, pyridostigmine and 3,4-diaminopyridine
Facioscapulohumeral dystrophy
“curious” scapula
during active arm abduction, the abnormal scapula internal rotates and becomes winged. the upper border of the scapula produces an abnormal appearance of the neck
features of facioscapulohumeral dystrophy?
LMN proximal weakness without sensory loss. usually asymmetrical
facial weakness precedes upper limb (shoulder) girdle weakness:
e.g. whistling, using straw, inflating balloons, closing eyes during sleep, smiling
shoulder girdle weakness:
- scapula winging
- difficulty in raising arms beyond shoulder height (abduction)
abdominal weakness:
protuberant abdomen, exaggerated lumbar lordosis
often also get distal weakness in LL with foot drop
proximal leg weakness is a late feature
symptoms usually develop in early adulthood
pathophysiology of facioscapulohumeral dystrophy
autosomal dominant inheritance
associated with truncation of non coding region of chromosome 4
–> protein produced toxic to muscle cells
-> leading to muscle degeneration and fat infiltration of skeletal muscle
beevor sign in facioscapulohumeral dystrophy?
movement of naval towards head when flexing neck
due to weaker lower abdominal muscles compared to upper abdomen
signs of facioscapulohumeral dystrophy?
- weakness in facial muscles (LMN)
- winging of scapula
- arm abduction with “curious scapular”
- beevor sign: weak lower abdominal muscles
- weakness in shoulder girdle muscles
- may have foot drop
investigations of facioscapulohumeral dystrophy?
for diagnosis:
based on history and exam, family history
genetic testing that identifies mutation in one of the genes regulating DUX4 expression for definitive diagnosis
other tests to support or help to rule out other similar appearing conditions:
- CK: should be normal-midly elevated not sky high
- EMG: can show nonspecific signs of muscle damage or irritability
- nerve conduction study: should be normal in a myopathy (if abnormal would point towards neuropathy)
- muscle biopsy: rarely indicated. findings in FSHD are non specific
- MRI can help visualize fatty infiltration of muscles, and muscle oedema. can help differentiate FSHD from other muscle diseases on the basis of pattern of muscles involved
management of facioscapulohumeral dystrophy?
generally supportive, no cure
MDT approach:
PTOT: gentle stretching and light exercises to preserve muscle flexibility and strength
- using assistive devices such as walking aids or mobility aids to reduce risk of falls and preserve independence
scapular fixation surgery can be considered to improve shoulder function and range of motion
Genetic counselling
Psychosocial support
screening and monitoring for complications associated with facioscapulohumeral dystrophy?
- dilated eye exam to look for retinal abnormalities. may need yearly evaluation by retinal specialist
- hearing test to look for hearing loss
- pulmonary function tests
- may have arrhythmias but no need routine screening unless develop symptoms (can just do ecg baseline)
pathophysiology of becker’s muscular dystrophy?
X linked recessive condition causing dystrophin gene mutation
-> dystrophin stabilizes muscle cell membrane. loss of dystrophin causes
-> muscle fibres undergo necrosis and are ultimately replaced with adipose and connective tissue
- same as Duchenne’s but beckers has a less severe reduction in dystrophin correlating with reduced severity of phenotype
features of Becker muscular dystrophy
usually age 8-25 years onset
progressive muscular wasting and weakness
calf muscle pseudohypertrophy
waddling gait
may present with dilated cardiomyopathy and arrhythmias
later symptoms;
respiratory failure
wheelchair bound
scoliosis
Investigations in Becker muscular dystrophy?
raised CK
Genetic testing: mutations in dystrophin gene
EMG
muscle biopsy: stain for dystrophin
management of Becker muscular dystrophy?
no cure, treatment generally supportive
MDT:
PTOT
Genetic counselling
features of limb girdle muscular dystrophy?
multiple gene and proteins identified
all show similar distribution of muscle weakness, usually proximal limb weakness and wasting
later might develop complications of cardiomyopathy, respiratory failure, dysphagia
ix of limb girdle muscular dystrophies?
to diagnose:
- CK: usually elevated
- take family history
- genetic testing
management of limb girdle muscular dystrophy?
refer to neuromuscular specialist
MDT approach:
PTOT
psychosocial support
cardiology and respiratory for cardio/resp complications
genetic counselling
congenital/inherited causes of proximal LMN pattern of weakness with no sensory involvement
muscular dystrophies:
myotonic dystrophy
facioscapulohumeral dystrophy
becker’s dystrophy
limb girdle muscular dystrophy
metabolic/endocrine causes of proximal myopathy?
hyperthyroidism/hypothyroid
cushings syndrome
vit D deficiency
neoplastic causes of proximal myopathy without sensory involvement
dermatomyositis
inflammatory/infectious causes of proximal myopathy?
polymyositis
dermatomyositis
drug causes of proximal myopathy
colchicine
statin
fibrates
telbuvidine
UMN pattern of weakness, with abnormal sensation, associated with a sensory level
transverse myelitis
myelopathy due to spinal cord lesion/ischaemia
features of transverse myelitis
weakness and numbness of limbs with sensory level.
most commonly thoracic segment lesion -> UMN in the lower limbs, spastic paraparesis
dysfunctional urethral and anal sphincter-> incontinence
dysfunction of autonomic nervous system -> high BP
if upper cervical segment of spinal cord is involved, all 4 limbs may be affected, with risk of respiratory failure
pathophysiology of transverse myelitis
inflammation of spinal cord
- extends horizontally throughout the cross section of the spinal cord
- > affects all the structures, like corticospinal tract, dorsal columns, spinothalamic tract, ant horn cells, spinocerebellar tract
exact cause is unknown
can be triggered by infection (viral, bacterial infection) or autoimmune (MS)
ix of transverse myelitis
to diagnose:
MRI spine (hyperintense signal on T2)
Lumbar puncture can help to rule out other causes:
CSF- pleocytosis, may have high IgG
treatment of transverse myelitis?
to reduce inflammatory reaction:
1st line: high dose corticosteroids
2nd line: plasmapheresis
UMN pattern of weakness with abnormal sensation (glove and stocking distribution) -> causes?
cervical myelopathy
medical myelopathy (e.g. B12 deficiency SCDC, neurosyphilis)
pathophysiology of subacute combined degeneration of the cord
degeneration of the dorsal columns and lateral corticospinal tracts as a result of b12 deficiency
features of subacute combined degeneration of the cord on examination?
bilateral spastic paraparesis
reduced light touch, vibration and propioception
pain sensation intact
positive babinski sign
features of cervical myelopathy?
depends on which level of spinal cord affected
usually
UMN signs - hyperreflexia, spastic weakness, hypertonia, pathological reflexes including Hoffman’s and Babinskis sign
can also have LMN signs at the level of the spinal cord compromise
sensory deficits
bowel/bladder symptoms
erectile dysfunction
causes of myelopathy?
congenital/ inherited: adrenoleucodystrophy, spinocerebellar degeneration, chiari malformation
metabolic/endocrine: SACD from B12 deficiency
neoplastic/paraneoplastic: primary or secondary
vascular/ degenerative: dural fistulae, spinal infarct, cervical spondylosis, rheumatological disease e.g. AS
inflammatory/ infectious: MS, NMO (including anti-MOG), epidural abscess, spinal TB, tabes dorsalis, HIV
human activity: trauma, iatrogenic
if not clear whether its UMN/ LMN what in the power can help?
pyrimadal pattern of weakness
e.g. hip flexion < extension, dorsiflexion< plantarflexion, abduction < adduction of hip, knee flexion < extension
abnormal inverted supinator reflex - what pathology
C6 pathology
c6 myelopathy features
weakness of brachioradialis, biceps and deltoid
loss of biceps reflex
inverted supinator reflex
features of hereditary spastic paraplegia
progressive stiffness and spasticity in the lower limbs
- due to destruction of axons in the spinal cord (primary motor neurons -> hence UMN disease)
sensory normal
bowel / bladder normal
management of hereditary spastic paraplegia?
baclofen to manage symptoms of spasticity
what is spinocerebellar ataxia?
a progressive degenerative genetic disease
- characterized by slowly progressive gait ataxia, poor coordination of hands, speech, eye movements
- frequently results in cerebellar atrophy leading to cerebellar signs
*Friedreich ataxia is a subtype but not common in asia
many subtypes -> just do genetic testing
features of spinocerebellar ataxia on examination?
UMN pattern
ataxia
cerebellar signs
ix of optic neuropathy?
depends on most likely underlying cause suspected
ask for further history of previous optic neuritis or myelitis
but should image MRI orbits to exclude compressive lesion
pathophysiology of multiple sclerosis?
autoimmune inflammatory condition in which lymphocytes attack and damage oligodendrocytes
-> demyelination of the CNS and optic nerves, which have oligodendrocyte-derived myelin, but does not affect the other cranial and peripheral nerves that have schwann cell myelin
T cells and macrophages infiltrate lesions, with demyelination and subsequent remyelination
-> leading to clinical pattern of relapse and remission
when axonal degeneration supervenes, a progressive pattern of disability emerges
any risk factors for Multiple sclerosis?
cigarette smoking
association with EBV infection
genetic:
female gender
increased risk in family members
features of multiple sclerosis?
commonest presenting syndrome: optic neuritis (painful, acute monocular visual loss with loss of colour vision)
other common manifestations:
spinal cord syndromes
ataxia
diplopia
hemiparesis
vertigo
assoc uthoff’s phenomenon (worse symptoms with heat)
Lhermitte’s phenomenon (tingling down spine and arms on neck flexion)
different temporal patterns in multiple sclerosis?
- relapsing-remitting: characterised by episodes of acute neurological deterioration with subsequent recover
- secondary progressive multiple sclerosis, gradual decline without discrete relapse episodes
- primary progressive MS (<10%): progressive neurological decline without any history of relapses
- relapsing-progressive MS: relapses superimposed upon gradual progression
diagnosis of multiple sclerosis?
clinical diagnosis: clinical events disseminated in time and space
supported by results of:
1) imaging: MRI being 1st line
2) CSF: 85% oligoclonal bands
3) neurophysiological e.g. visual evoked potentials
management of multiple sclerosis?
infection may trigger relapses or cause deterioration of pre-existing symptoms.
active infection should be excluded and treated before specific MS treatment is commencced. e.g. UTI - very common ivo freq bladder dysfunction in MS
MS specific treatment:
- IV methylprednisolone 1g daily 3 days may speed the rate of recovery from an acute relapse
- DMARDS
- Symptomatic treatment
MDT approach involving neurologist, PT OT ST
- to maintain mobility
- walking aids
- graded exercise programmes
symptomatic treatment for MS:
treatmets for spasticity?
PT: maintain range of movement and reduce spasms
Baclofen, gabapentin; Benzodiazepines e.g. diazepam/ clonazepam: -> promote muscle relaxation
Botulinum toxin
Cannabinoid preparations e.g. nabiximols: only licensed for patients in whom multiple other agents have failed
symptomatic treatment for MS patients with bladder and bowels symptoms including urgency, frequency, incontinence, retention and constipation?
Anticholinergic drugs e.g. oxybutynin, solifenacin -> improve symptoms of over activity
urinary cathterisation: intermittent self catheterisation or long term catheters in patients with incomplete voiding which can lead to frequent UTIs
intravesicle botulinum toxin injections: may be combined with intermittent self catheterisation for very problematic bladder overactivity
DMARDs for multiple sclerosis
IFN beta (sc/IM): reduce annual relapse rate by 1/3
Glatiramer acetate (sc injection): reduce relapses requiring hospital admission by 50%
Oral:
- Fingolimod
- Teriflunomide
- Dimethyl fumarate
Monoclonal antibody infusion:
- Natalizumab (against A4-integrin): reduces relapse by 68%
- Alemtuzumab (against CD52): reduces relapse rate by 70%
Counselling pregnant patient with multiple sclerosis?
- decreased rate of relapse in 1st and 2nd trimester
- increased rate of relapse in 3rd trimester and post partum
- corticosteroids can be used to treat relapses
- minimal evidence exists about safety of DMARDS and these are often suspended during pregnancy
What is Neuromyelitis optica?
autoimmune disease
characterized by acute inflammation of the optic nerve and spinal cord
assoc with severe often bilateral optic neuritis
spinal cord syndrome with longitudinally extensive transverse myelitis
- can be simultaneous or successive
bladder/ bowel dysfunction may occur
ix in neuromyelitis optica?
antibodies against aquaporin 4 (IgG)
anti- myelin oligodendrocyte glycoprotein (MOG) antibodies may account for some aquaporin seronegative cases
MRI brain/ spinal cord
LP: <30% of patients will have oligo clonal bands. 30% may have high WBC >50
management of neuromyelitis optica
steroids in acute attacks e.g. IV methylprednisolone
+/- plasmapheresis
symptom management
relapse prevention
steroid sparing agents e.g. azathioprine, MMF
cyclophosphamide, rituximab
monoclonal antibodies e.g. eculizumab targetting C5, inebilizumab targeting CD 19, satralizumab targeting IL 6R
important to note that certain immunosuppressants used to treat MS - such as IFN-beta, fingolimod, natalizuman, alemtuzumab worsen NMO disease progression and should not be used to treat NMO
pathophysiology of neuromyelitis optica?
majority - antibodies against Aquaporin 4
-> which causes astrocyte injury and loss
lesions in Multiple sclerosis vs NMO?
MRI orbits: usually long sergment involved in NMO compared to MS
MRI spine: typically long lesion >/= 3 vertebral segments in NMO compared to MS (</=2 segments)
what is anti-MOG syndrome or MOGAD: MOG antibody disease
inflammatory demyelinating disease of the CNS
- associated with serum anti-myelin oligodendrocyte glycoprotein antibodies (MOG)
- oligodendrocytopathy
differential of optic neuritis?
- multiple sclerosis
- AQP4 +ve NMO
- MOG related inflammation
- Inflammatory / autoimmune: sarcoid, lupus, granulomatosis with polyangiitis
- Infectious: Lyme, syphilis, TB
- Idiopathic
features of MOG related disease?
F:M 1:1
- may present with optic neuritis, acute disseminated encephalomyelitis, transverse myelitis, NMOSD
ix of MOG related disease?
anti-MOG antibody
LP: <5% will have oligoclonal bands in CSF, 25-50% may have raised WBC > 50
prior to starting immunosuppression or high dose steroids, what are some investigations to be done?
infections: screen pTB, Hep B/ C
vaccinations: flu yearly, pneumococcaly 5 yearly, covid vaccination
Contraception advice for immunosuppressives
Steroids:
Bone mineral density + vit D - risk of osteoporosis
peptic ulcer disease
K replacement
Acne
Cataracts + raised IOP
DM and HTN
binocular visual blurring - first question to ask?
does the blurring improve when you close one eye?
if so -> dealing with diplopia
features of cavernous sinus syndrome?
CN III, IV, VI
+ V1, V2
+ Horners syndrome may be involved
+ may be painful
features of superior orbital fissue syndrome?
CN III, IV, VI
+ V1
features of orbital apex syndrome?
CN III, IV, VI
+ V1
+ Cranial nerve 2!
potential causes of orbital apex pathology?
inflammatory/ infectious:
GCA/takayasu, granulomatosis with polyangiitis, igG4, sarcoidosis
infections e.g. bacterial parasinus infections, TB, fungal sinusitis, cysticercosis (parasites), zoster virus
vascular: ICA aneurysm, carotido-cavernous fistula
neoplastic: mass lesion can be primary or secondary lesion at orbital apex
metabolic/ endocrine: thyroid eye disease
any ophthalmoplegia seen on examination, what do you need to do?
rule out myasthenia gravis, muscle disorder (e.g. thyroid eye disease)
CN problem?
painful isolated CN III palsy with dilated pupil?
posterior communicating artery aneurysm unless proven otherwise
Bilateral ptosis -> what to examine for next?
are pupils involved?
if pupils involved -> suggestive of CNIII palsy and can rule out myopathy/ myasthenia gravis
bilateral ptosis -> normal pupils -> what to examine for next?
EOM
-> if EOM affected, may be bilateral CN III
bilateral ptosis with normal EOM and normal pupils, what to examine for next?
fatiguability to suggest myasthenia gravis
grip myotonia and percussion myotonia to suggest myotonic dystrophy
what pathology may cause bilateral ptosis due to bilateral CN III involvement?
GBS/ Miller Fisher syndrome
Midbrain: nuclear III
what cranial nerves are implicated in jugular foramen pathology?
CN IX, X, XI
what cranial nerves are implicated at cerebellopontine angle
Usually CN VIII first - sensorineural hearing loss with tinnitus
lower motor neuron CN VII palsy
CN V - facial sensory loss
any cranial nerve pathology: how to evaluate for brainstem pathology?
look for long tract or cerebellar signs
-> do pronator drift
-> babinskis
-> dysdiadochokinesia/ dysmetria
if lesion in midbrain (affects CN III, IV): look for vertical gaze abnormalities as well
if lesion is in pons (CN V, VI, VII, VIII): look for horizontal gaze abnormalities
if lesion is in medulla (CN IX, X, XI, XII): look for horner’s (lat medullary syndrome)
any cranial nerve pathology: how to screen and evaluate for meningeal/ skull base disorder
think of acute/chronic meningitis
think of base of skull pathology e.g. NPC, radiation
any headache?
any epistaxis/ lymphadenopathy?
neck stiffness?
any cranial nerve pathology: how to evaluate and screen for peripheral neuropathy
evaluate for weakness with usually glove and stocking sensory loss suggestive of GBS,
areflexia, incoordination
any cranial nerve pathology, think about cranial nerve clubs such as?
cavernous sinus - CN III, IV, VI, V1/2
orbital apex - involves 2 along with the above
jugular foramen - 9, 10, 11
cerebellopontine angle - VIII + VII/ V
systemic approach to falls
first order gait control structures: examine for weakness/ numbness
muscle
NMJ
peripheral nerve
anterior horn cell
2nd order gait control structures: examine for ataxia
cervical myelopathy
cerebellar ataxia
bilateral severe vestibulopathy
3rd order gait control structures:
parkinsonism
gait apraxia
cerebellar eye signs?
gaze evoked nystagmus
down/ upbeat nystagmus
saccadic dysmetria (“past pointing” of the eyes. goes past midpoint before coming back to the middle)
saccadic pursuit (jerky pursuit)
patient with parkinsonism what to examine for?
1: demonstrate bradykinesia, cogwheel rigidity, resting tremor
- tremor on general inspection
- tone for cogwheel rigidity
- bradykinesia: use hand movements
- face: hypomimia
- gait: small shuffling gait, reduced arm swing
should also demonstrate that power is full, sensation normal
2. Test for parkinsons plus
eyes: for vertical gaze palsy, cerebellar eye signs (MSA)
cerebellar signs: MSA
check for limb apraxia ie. opening jars: corticobasal degeneration
3. offer:
autonomic signs: postural hypotension, urinary incontinence, impotence
in a young patient: look for KF rings in the eyes
cognitive history
ask for other complications of parkinsons: sleep/ mood
patient with parkinsonism: what to ask for to complete your examination
drug history, family history, liver disesase (wilson disease)
falls, autonomic symptoms
hallucinations (DLB)
hx of hypoxic cerebral injury/ encephalitis/ osmotic demyelination
mental state examination for cognitive impairment
response to madopar
occupational exposure: manganese mine
in parkinsonism, what additional things to assess for after confirming the patient has parkininson’s?
assess severity of disease
assess disability and handicap -> get MDT to assess and help alleviate
assess for complications e.g. dyskinesia, depression, behavioural issues, osteoporosis, falls, recurrent infections
and put in place pre-emptive proactive management and surveillance plan
approach to cerebellar disorders?
elicit all signs in eye, limbs and speech
then
examine for underlying cause
4 question approach to dizziness?
- vertigo or syncopal, faint like dizziness?
- if vertigo, are there signs and symptoms of CNS pathology or peripheral vestibular pathology?
- how long are the vertigo spells?
- is this the only episode or is it recurrent?
ataxia -> what to differentiate between?
cerebellar ataxia:
look for other cerebellar signs like nystagmus, intention tremor, dysdiadochokinesia
sensory ataxia:
usually has abnormal sensory signs e.g. propioception, vibration, light touch
- sensory ataxia would be able to do finger nose test with eyes open but not with eyes closed
- need to then differentiate between central cause (e.g. myelopathy) or peripheral causes (e.g. peripheral neuropathy)
causes of predominantly sensory peripheral neuropathy?
Endocrine/Metabolic: DM, Hypothyroidism, uraemia, Vit B12 deficiency
Infectious: HIV, Leprosy, Lyme disease
Inflammatory/Immune mediated: Vasculitis, Sjogrens, Amyloidosis
Neoplastic: anti Hu antibody associated sensory neuropathy
Drugs: isoniazide, pyridoxine, cisplatin
Human activity: Toxins: Alcohol
utility of doing nerve conduction studies in peripheral neuropathy?
useful in delineating demyelinating from axonal causes. demyelinating tend to be more immune mediated and would require further investigations for such causes
what is Kennedy’s disease
subtype of motor neuron disease
aka SBMA - Spinal and bulbar muscular atrophy
a rare adult onset X linked recessive Lower motor neuron disease caused by trinucleotide CAG repeat expansions in exon 1 of the androgen receptor gene
perioral fasciculations?
think of kennedy’s disease
spinal and bulbar muscular atrophy
Spastic paraparesis with cerebellar signs in the LL?
Consider
1) demyelinating disease
2) Friedrich’s ataxia
3) spinocerebellar degeneration
4) cervicomedullary junction lesion
Spastic paraparesis, how to quickly test UL as well to localise lesion?
Pronator drift, tone, reflexes
1) inverted supinator reflex = absent biceps jerk, weak brachioradialis jerk, brisk finger flexion and triceps jerk: C5/6 compressive lesion
2) jaw jerk: above pons
3) tongue fasciculations: above CN XII
Bilateral LL weakness with UMN pattern (spastic paraparesis), sensation abnormal. UL normal. Where is the lesion?
Between T1 and L2
Bilateral LL weakness with UMN pattern (spastic paraparesis), sensation abnormal. UL normal. Lesion likely at T1-L2, what to examine for next?
Look at back
Test for sensory level
Test abdominal reflexes (T7, T10, L2)
- if absent then above T7
- if present then T7 to L2
- Beevor sign: neck flexion causes navel to move upwards, when upper abdominals stronger than lower. Can be seen in T9-10 lesion.
prognosis of charcot marie tooth disease?
normal life expectency
disability varies
investigations for a LMN pattern of proximal weakness to evaluate for myopathy?
Electromyogram: helpful in diagnosing muscular dysfunction
NCS: to rule out nerve dysfunction
important to rule out reversible causes (inflammatory/immune):
myositis panel e.g. anti-HMGCR
dermatomyositis/ polymyositis e.g. ENA panel
endocrine/metabolic: TFTs
Genetic testing for congenital muscular dystrophies
unsteadiness in the stem: think about?
sensory ataxia
cerebellar ataxia
parkinsons
recurrent falls: think about?
parkinsonism
Cerebellar ataxia
General Neurolocalisation for weakness
Muscle
NMJ
Nerve
Anterior Horn Cell
Spinal cord
Subcortical/Cortical
LMN weakness with no sensory loss, neurolocalisation
Muscle
NMJ
Anterior horn cell (Look for fasciculations and UMN signs)
Pure motor neuropathy
LMN weakness with sensory loss, neurolocalisation
nerve problem
- peripheral nerve distribution? radiculopathy? plexopathy?
- don’t forget cauda equina
UMN weakness with sensory loss, neurolocalisation?
spinal cord (myelopathy/ myelitis)
- rmb to look for sensory level if any
*always remember demyelination as a cause (MS)
UMN weakness no sensory loss, neurolocalisation?
Cortical/subcortical
could be Anterior horn cell: primary lateral sclerosis
hereditary spastic paraparesis
