Neurology Flashcards
What does the dorsal column pathway include?
Proprioception
Vibration
Finetouch
What does the spinothalamic pathway include?
Pain
Temperature
What is the parasympathetic NS?
Rest and digest
What is the sympathetic NS?
Fight or flight
What does the autonomic NS include?
Parasympathetic NS
Sympathetic NS
Excitatory neurotransmitters?
Glutamate Acetylcholine Noradrenaline Serotonin Dopamine
Inhibitory neurotransmitters?
GABA
Primary headache syndromes?
Migraine Tension-type headache Cluster headache Medication overuse headache Benign cough headache Benign exertion headache Hypnic headache 'Ice pick' headache Coital/sex headache
Migraine criteria?
> 5 attacks
4-72 hours
≥ 2 of: unilateral, pulsating, moderate/severe pain. avoidance of routine physical activity
Nausea and/or vomiting OR photophobia/phonophobia
Migraine prophylaxis?
B-blockers e.g. propanolol
Anti-epileptics e.g. topiramate, sodium valproate
Anti-depressants e.g. amitryptyline
Migraine treatment?
Aspirin 900 mg
Anti-emetics e.g. metoclopramide
Triptans
Tension-type criteria?
≥ 10 episodes
30 mins-7 days
≥ 2 of: bilateral, non-pulsating, mild/moderate pain, not aggravated by routine physical activity
No nausea/vomiting
Cluster headache criteria?
≥ 5 attacks Severe/very severe unilateral 15-180 mins Ipsilateral conjunctival injection, lacrimation, nasal congestion, rhinorrhoea, eyelid oedema, forehead/facial sweating, mitosis/ptosis, sense of restlessness/agitation Frequency 1-8 per day
Cluster headache treatment?
High flow oxygen
SC triptan
Avoid triggers
Cluster headache prophylaxis?
Corticosteroids
Verapamil
Lithium
Secondary headache types?
Vascular: subarachnoid haemorrhage, intracerebral haemorrhage, subdural haematoma, stroke, intracranial venous thrombosis, carotid/vertebral direction, GCA cerebral venous thrombosis
Infection: meningitis, encephalitis
Pressure: raised ICP, low ICP
Ocular: glaucoma, optic neuritis, eye strain
Facial pain: trigeminal neuralgia
Other: hypercapnia, drugs (e.g. anti-hypertensives)
Red flags for headaches?
Explosive onset/very severe at onset Recent significant change in pattern Altered mental status Onset with exertion, cough, sexual activity Age > 50 years Immunosuppression Neurological abnormalities Decreased LOC Meningismus, fever
New, acute headache?
Intra-cranial infection
Intra-cranial haemorrhage
First presentation of benign intermittent headache
Recent, subacute headache?
Raised ICP
GCA
Transient benign headache
Longer-standing, chronic headache?
Primary headache syndrome
Headache alone?
Benign cause
Headache and nausea, vomiting, photo/phono-phobia?
Serious cause- meningitis, encephalitis
Migraine
Headache and fever, infectious features?
Meningitis
Encephalitis
Headache and neurological features?
Migraine
Serious cause
Headache examination and investigations?
History Infection features: temp, rash Blood pressure URT examination Neurological examination Cervical spine Bloods: ESR Lumbar puncture: pressure, white cells (infection, inflammation), bilirubin (subarachnoid haemorrhage), xanthrochromic (subarachnoid haemorrhage)
Causes of blackouts?
Syncope
Epileptic seizure
Functional/non-epileptic seizure
Hypoglycaemia
Features of an epileptic seizure?
Long duration Confusion Long recovery Cyanosis Tongue biting Jerking Can have stiffness May have a warning
Features of syncope
Short duration Quick recovery Pallor Can have some jerking May/may not have a warning
Blackout investigations?
May not need any
ECG
Some syncope cases: ambulatory ECG, tilt-table testing
Some epilepsy cases: EEG, cerebral imaging
Blackout definition?
Episodes of loss of consciousness
Funny turns definition?
Discrete episode(s) due to some sort of brain event
Funny turn causes?
TIA
Epileptic seizure
Migraine
Other: dissociation/depersonalisation/derealisation, anxiety/panic attacks, hypoglycaemia, sleep-related turns
Coma definition?
State of unconsciousness where a person:
- Cannot be awakened
- Fails to respond normally to painful stimuli, light, sound
- Lacks normal sleep-wake cycle
- Does not initiate voluntary actions
Common causes of coma?
Focal brain lesions:
- Haemorrhagic stroke
- Intracranial mass lesions- tumour, abscess
Diffuse disorders:
- Post cardiac/respiratory arrest
- Overdose
- Subarachnoid haemorrhage
- Metabolic disturbances- hypoglycaemia, hepatic failure, renal failure
- Infection- meningitis, overwhelming sepsis
- Post-epileptic seizure
- Non-convulsive status epilepticus
Neurological assessment for coma?
History General examination Pupil examination Eye movements GCS CT brain Drug levels Lumbar puncture
Immediate coma management?
Airways: open, stabilise cervical spine
Breathing: ventilate, intubate
Circulation: pulse, perfusion, BP, correct hypovolaemia, correct arrhythmias, large bore IV access
Treat hypoglycaemia
Ongoing coma supportive care?
Monitor
Empty stomach contents
DVT prophylaxis
Maintain blood gas and electrolyte homeostasis
Urinary catheterisation
Regular turning/air mattress to avoid pressure sores
Concussion definition?
Traumatic brain injury that alters the way your brain function.
Effects are usually temporary but can include headaches, problems with concentration, balance, co-ordination.
The brain requires time to recover
Mechanisms of brain injury?
Contact: coup and centrecoup, causes fractures and contusions
Inertial: acceleration and deceleration
Strain: deformity when mechanical force is applied
Differential movements
Brain hernias?
Uncal herniation Central transtentorial herniation Subfalcine herniation Extracranial herniation Upwards cerebellar herniation Tonsillar herniation https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=2ahUKEwj4zb2HvOnhAhWD3eAKHfMJC_QQjRx6BAgBEAU&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FBrain_herniation&psig=AOvVaw0O1pUWRy8GBLvxUUHda2Qh&ust=1556220710633814
Delirium definition?
Acute onset Fluctuating course Inattention Disorganised thinking and/or altered LOC There is a precipitating cause
Dementia definition?
Due to disease of the brain
Chronic/progressive
Disturbance of multiple higher comical functions
Conscious not changed
Cognitive functions result in functional impairment
Progressive
Irreversible (in most cases)
Frontal lobe functions?
Executive function Adaptive behaviour Personality- especially motivation, inhibition Impulse control Planning and initiation Behaviour sequencing Social behaviour Language production- in Broca's area
Temporal lobe functions?
Memory
Language comprehension- in Wernicke’s area
Parietal lobe functions?
Visuospatial skills
Praxis
Occipital lobe functions?
Vision
Alzheimer’s pathogenesis?
Beta amyloid plaques and tau tangles
Alzheimer’s features?
Gradual onset Cognitive impairment Progressive Visuospatial function affected early Defects: short-term memory, language, praxis, visuospatial, executive functioning
Alzheimer’s stages?
First 2-3 years post diagnosis
Moderately severe (3-6 years)
Severe (6-10 years)
Alzheimer’s management?
Cholinesterase inhibitors for symptoms
Vascular dementia features?
After stroke
Step wise deterioration
Vascular dementia management?
Optimise vascular risk Stop smoking Reduce cholesterol BP control AF treatment
Dementia with Lewy Bodies features?
Fluctuates
Visual hallucinations
Parkinsoniam
Can appear as delirium initially
Dementia with Lewy Bodies management?
Avoid antipsychotics
Cholinesterase inhibitors for symptoms
Frontotemporal dementia features?
45-65 year old onset
Different types
Overlaps with MND
Frontotempotal dementia management?
Non available
Dementia management?
Symptoms in Alzheimers and DLB: cholinesterase inhibitors
Treat exacerbating issues: remove sedation, treat depression
Post-diagnostic support for family etc.
Social support
Power of Attorney recommendation
Support for carers
Epilepsy defintion?
Manifestation of abnormal paroxysmal neuronal discharges
Recurrent spontaneous seizures
After ≥ 2 seizures
Types of epilepsy?
Focal onset
Generalised onset
Unknown onset
Sub-types of focal onset epilepsy?
Focal aware
Focal impaired awareness
Focal to bilateral tonic-clonic
What causes focal onset epilepsy?
Acquired after damage
What causes generalised onset epilepsy?
Usually genetic
Sub-types of generalised onset epilepsy?
Absence Tonic-clonic Myoclonic Atonic Infantile spasms
Focal seizure management?
Carbamazepine
Lamotrigine
Generalised tonic-clonic management?
Sodium valproate
Lamotrigine
Absence management?
Sodium valproate
Ethosuximide
Myoclonic management?
Sodium valporate
Tonic or atonic management?
Sodium valporate
Lamotrigine
What is epileptic surgery for?
Focal epilepsy
Symptomatic focal- temporal, frontal, occipital lobe
Status epilepticus definition?
> 30 minutes of continuous seizure activity or a series of seizures without full resolution between
How to manage status epilepticus?
ABCDE assessment Benzodiazepine IV If unable PR/buccal Repeat benzodiazepine Phenytoin IV- need cardiac monitoring and notify ICU/anaesthetist
Features of parkinsonism?
Bradykinesia
Rigidity
Tremor
Postural instability
Causes of Parkinsonism?
Drug-induced
Idiopathic Parkinson’s disease
Other primary degenerative disease
Miscellaneous conditions
Pathogenesis of idiopathic Parkinson’s disease?
Lewy bodies
Substantia nigra neuronal death
Related loss of neuromelanin
Can treatment cause disease modification/prophylaxis in Parkinsons?
No
Parkinsons medication?
Direct dopamine agonists- ropinorole Levodopa Selegeline (alternative to DDAs) Amantadine (weak dopamine agonist) Anti-cholinergic drugs
Long term problems with Parkinsons medications?
Treatment is only symptomatic Drug toxicity CNS plasticity Reduced efficacy Shorter durations of response Fluctuations in disability Unpredictable and variable response Emergence of involuntary movements- chorea, athetosis, dystonia Confusion, hallucinations, dementia
Difference between stroke and TIA?
Stroke > 24 hours
TIA < 24 hours
Stroke due to: cerebral ischaemia or haemorrhage
TIA due to: inadequate cerebral/ocular blood supply
Fixed risk factors for stroke and TIA?
Age M > F Race Previous vascular event Hereditary High fibrinogen Cholesterol- high LDL
Modifiable risk factors for stroke and TIA?
Hypertension Smoking High hip to waist ratio Hyperlipidaemia Diabetes mellitus Alcohol Depression Heart disease- AF Oestrogen containing drugs Polycythae,oa
Stroke causes?
80% ischaemic
15% haemorrhage
5% unknown
Presentation of a vascular lesion in stroke?
Sudden onset No warning Maximal at onset Body parts affected simultaneously Gradual improvements over time Repeated events Hemispheric pattern of deficit LOC is uncommon
How to investigate a stroke/TIA if presentation is ≤ 7 days?
CT scan
How to investigate a stroke/TIA if presentation is ≥ 7 days?
MRI scan
Mimics of stroke/TIA?
Sepsis Syncope Seizure Spreading migraine aura Functional
How to diagnose a stroke/TIA?
Localise the lesion- symptoms, neurological signs, imaging confirmation
Types of stroke?
Total anterior circulation stroke
Partial anterior circulation stroke
Lacunar stroke
Posterior circulation stroke
How does a total anterior circulation stroke present?
All of:
Unilateral weakness of face, arm and leg
Homonymous hemianopia
Higher cerebral dysfunction
How does a partial anterior circulation stroke present?
2 of:
Unilateral weakness of face, arm and leg
Homonymous hemianopia
Higher cerebral dysfunction
How does a posterior circulation stroke present?
1 of:
Cranial nerve palsy and a contralateral motor/sensory deficit
Bilateral motor/sensory deficit
Conjugate eye movement disorder
Cerebellar dysfunction
Isolated homonymous hemianopia or cortical blindness
How does a lacunar stroke present?
1 of: Pure sensory stroke Pure motor stroke Sensori-motor stroke Ataxic hemiparesis
Which stroke types are usually caused by carotid disease?
Total anterior and partial anterior
Which stroke types have higher recurrence?
Partial anterior and posterior circulation
Which stroke type has the highest chance of death?
Total anterior
What increases risk of stroke following a TIA/minor stroke?
Older age Hypertension Clinical features- weakness, speech Longer duration Diabetes mellitus Positive imaging
Ischaemic stroke management?
Hyperacute:
Thrombolysis
CLOT retrieval
Neurosurgical decompression
Acute: Stroke unit Supportive care- fluids, feeding Prevention and management of complications e.g. DVT prevention if immobile Manage co-morbidities
Rehabilitation
Secondary prevention: Exercise Smoking cessation Healthy weight Diet BP control Antiplatelets Statin Anticoagulation if in AF PFO closure if needed Carotid endarterectomy
Haemorrhagic stroke management?
Hyper-acute:
Sometimes BP lowering
Acute treatment: Stroke unit Supportive care- fluids, feeding Prevention and management of complications e.g. DVT prevention if immobile Manage co-morbidities
Secondary prevention: Exercise Smoking cessation Healthy weight Diet BP control Avoid antiplatelets Avoid anticoagulation
What is the thrombolytic drug used?
Alteplase 1 mg/kg
Contraindications to thrombolysis after stroke?
Minor surgery in last 14 days
GI/urinary tract bleeding in last 21 days
History of ICH, intracranial malignancy or intracranial AVM
Symptoms suggestive of subarachnoid haemorrhage
BP > 185 systolic or > 110 diastolic
INR > 1.7
Hyperglycaemia > 20
Hypoglycaemia < 3
What is MS?
Inflammatory disease affecting all of the CNS
Types of MS?
Relapse-remitting (+ secondary progressive)
Fulimant
Primary progressive
Common nerves affected in MS?
Optic nerve -> optic neuritis
Medial longitudinal fascicularis -> internuclear ophthalmoplegia
Corpus callous -> often asymptomatic
Spinal cord
MS presentation?
Visual:: optic neuritis, optic atrophy, Uhthoff’s phenomenon, internuclear ophthalmoplegia
Sensory: pins and needles, numbness, trigeminal neuralgia, Lhermitte’s syndrome
Motor: spastic weakness (legs), transverse myelitis
Cerebellar: ataxia, tremor
Other: urinary incontinence, sexual dysfunction, intellectual deterioration
Features contraindicatory to MS?
Diminished/lost reflexes Patterns of weakness that fit a single root/nerve/very variable Lots of pain Seizures Reduced consciousness Respiratory compromise
Investigations in suspected MS?
Exclude other diagnoses
Routine bloods
MRI brain and spine
Consider LP if brain scan is normal
How to diagnose MS?
≥ 2 attacks with ≥ 2 objective clinical lesions
if there is lower clinical presentation you need MRI, SCF evidence
Types of treatment for MS?
Symptomatic
Acute relapse treatment
Disease modifiers
Symptomatic treatment for MS?
Physiotherapy Ani-spasmodics Neuropathic pain treatment Aids Fatigue Spasticity: baclofen, danrolene, tizanide, physiotherapy, botox Bladder dysfunction: unstable bladder (oxybutynin, tolterodine), uncoordinated bladder (self catheterisation) Erectile dysfunction: sildenafil
Acute relapse treatment for MS?
Oral steroids- 500 mg methylprednisolone
Disease modifying treatment for MS?
Beta-interferon: avonex, rebid, betaferon, extavia
Glatiramer acetate
Natalizumab
Is there any treatment for progressive MS?
No licensed treatment
Potential neuroprotective treatment- lamotrigine/phenytoid
What is myasthenia gravis?
Disorder of neuromuscular junction
Myasthenia gravis presentation?
Fatiguable weakness Diurnal variation Diplopia (double vision) Dysarthria Ptosis Dysphagia Dyspnoea Neck weakness
What exacerbates the features of myasthenia gravis?
Pregnancy Hypokalaemia Infection Over-treatment Change of climate Emotion Exercise Gentamicin Opiates Tetracycline Quinine Beta blockers
Investigations in suspected myasthenia gravis?
Neuroimmunology- anti-AChR antibody, anti-MUSK antibody
Bloods: TFTs, B12
CT mediastinum
Electromyography
What types of treatment options are there for myasthenia gravis?
Symptomatic
Surgical
Immunosuppression
Symptomatic treatment for myasthenia gravis?
Anti-cholinesterase
Surgical treatment for myasthenia gravis?
Thymectomy
When to consider surgery for myasthenia gravis?
Generalised myasthenia gravis
< 50 years
AChR antibody positive
Immunosuppression treatment for myasthenia gravis?
Corticosteroids
Azathioprine
Alternatives: methotrexate
IV immunoglobulin or plasmapheresis
What medications to avoid in myasthenia gravis?
Gentamicin Clarithromycin Beta blockers Sedative drugs Calcium channel blockers Aminoglycoside antibiotics and erythromycin Benzodiazepines Curare-type muscle relaxants
Presentation of Lambert-Eaton myasthenia syndrome?
Subacute proximal weakness
Gait difficulty
Sensory and autonomic disturbances, especially dry mouth
Bulbar and ocular muscles are rarely affected
Treatment of Lamber-Eaton myasthenia syndrome?
Symptomatic: 3,4-diaminopyridine
Immunosuppression and plasmapheresis
Treat underlying tumour
What is a myopathy?
Primary disorder of muscle with gradual onset symmetrical weakness
Acquired causes of myopathy?
Inflammatory Endocrine Associated with systemic illness Drug induced Toxic
Hereditary causes of myopathy?
Muscular dystrophies Myotonias Channelopathies Metabolic myopathies Mitochondrial myopathies
Signs in favour of a myopathy?
Gradual onset of symmetrical proximal weakness Specific muscle groups affected Preserved tendon reflexes No paraesthesia or bladder problems No fasciculation
Myopathy symptoms?
Cramp
Contractures
Myotonias- impaired muscle relaxation after forceful voluntary contraction
Investigations if suspect a myopathy?
Bloods- ESR, CK, AST, LDH
EMG
Muscle biopsy
Genetic testing
What is muscular dystrophy?
A group of genetic diseases with progressive degeneration and weakness of specific muscle groups
How do muscular dystrophies present?
Unusually firm muscles (infiltration by fat/connective tissue)
Marked variation in size of individual muscle fibres on histology
Types of muscular dystrophy?
Duchenne’s muscular dystrophy
Becker’s muscular dystrophy
Fascioscapulohumeral muscular dystrophy
What is a myotonic disorder?
Causes stiffness, limitation of movement, sometimes weakness and tonic muscle spasm
Contractions usually provoked by cold and direct muscle stimulation
What is radiculopathy?
Nerve root compression
What is myelopathy?
Compression of the spinal cord
Causes of radiculopathy?
Acute disc
Spondylosis
Tumours
Inflammatory conditions e.g. shingles
Presentation of radiculopathy?
Pain- in nerve root distribution, disc prolapse, mechanical causes e.g. coughing, spinal tenderness
Weakness and reflex changes- in nerve root distribution
Sensory loss- in nerve root distribution
What is myeloradiculopathy?
Presence of UMN signs or sensory signs below the level of the radiculopathy in cervical spine
What is polyradiculopathy?
Compression of more than one nerve root
Causes of polyradiculopathy?
Lumbar canal stenosis
Inflammatory e.g. Guillain-Barré syndrome, inflammatory meningitis, sarcoidosis, neoplastic process in the spinal fluid
Presentation of C5 radiculopathy?
Weak deltoid and supraspinatus
Reduced supinator jerks
Numb elbow
Pain in neck/shoulder and radiating down front of arm the elbo
Presentation of C6 radiculopathy?
Weak biceps and brachioradialis
Reduced biceps jerk
Numb them and index finger
Pain in shoulder radiating down arm below elbow
Presentation of C7 radiculopathy?
Weak triceps and finger extension
Reduced triceps jerk
Numb middle finger
Pain in upper arm and dorsal forearm
Presentation of T1 radiculopathy?
Was in all intrinsic hand muscles
Horner’s syndrome
Pain in upper anterior and medial arm
Presentation of L2 radiculopathy?
Weak hip flexion and adduction
Pain across upper thigh
Presentation of L3 radiculopathy?
Weak knee extension and hip abduction Reduced knee jerk Numb from mid thigh to just below knee Positive femoral stretch test Pain across lower thigh
Presentation of L4 radiculopathy?
Weak knee extension Reduced knee jerk Numb on medial portion of lower leg Positive femoral stretch test Pain across lower thigh
Presentation of L5 radiculopathy?
Weak toe dorsiflexion and eversion
Numb anterior lower leg down to foot and lateral lower leg
Positive sciatic stretch test
Pain across lateral shin to dorm of foot and great toe
Presentation fo S1 radiculopathy?
Was ankle plantarflexion, toe inversion, knee flexion
Reduced ankle jerk
Positive sciatic stretch test
Pain across posterior calf to lateral foot (sole) and little toe
Investigations in suspected radiculopathy?
MRI of relevant spinal level
EMG
CSF examination- in multiple radiculopathy or if evidence of systemic illness
Treatment of lumbar disk disease (radiculopathy)?
Rest then mobilise
Education to avoid injury
Consider surgery if: radicular pain continues, neurological deficit
Treatment of cervical disk protrusions (radiculopathy)?
Often improves spontaneously or with conservative treatment
Conservative treatment: physiotherapy, soft collar, traction
Consider surgery if: pain persists or marked radicular weakness
Treatment of benign compressive tumours (radiculopathy)?
Surgical decompression
Presentation of acute cauda equina compression?
Altering/bilateral root pain in legs Saddle anaesthesia Loss of anal tone Bladder/bowel/sexual changes Distal sensory loss in feet
Treatment of cauda equina syndrome?
Disk prolapse -> MRI and neurosurgeons
Malignancy -> high dose steroids, radiotherapy, oncologists
Treatment: urgent surgical decompression
Treatment of lumbar canal stenosis (polyradiculopathy)?
Surgical decompression
Red flags for back pain?
< 20 years > 55 years Acute onset in elderly people Constant/progressive pain Nocturnal pain Worse pain on being supine Fever, night sweats, weight loss PMH of malignancy Abdominal mass Thoracic back pain Morning stiffness Bilateral or alternating leg pain Neurological disturbance Sphincter disturbance Current/recent infection Immunosuppression Leg claudication or exercise related leg weakness/numbness
What nerve roots contribute to the median nerve?
C6-T1
What is median nerve compression associated with?
Pregnancy Rheumatoid arthritis Hypothyroidism Diabetes Acromegaly Myeloma Idiopathic
Presentation of median nerve compression at the wrist?
Carpel tunnel syndrome
Weakness of abductor policies brevis
Sensory loss over radial 3.5 fingers
Presentation of median nerve compression due to anterior interosseous nerve lesions?
Weakness of flexion of distal phalanx of the thumb and middle finger
Treatment for carpel tunnel syndrome?
Splinting
Local steroid injection
Consider decompression surgery
Two causes of mononeuropathy?
Axonal injury
Focal demyelination/conduction block
Causes of axonal injury mononeuropathies?
Vasculitis Diabetes mellitus Sarcoidosis Leprosy HIV CMV Lyme Hepatitis C
Causes of focal demyelination/conduction block mononeuropathies?
Chronic inflammatory demyelinating polyradiculopathy- MADSAM, MMN
Multiple compression neuropathies- hypothyroidism, diabetes mellitus
Hereditary neuropathy with liability to pressure palsy (HNPP)
Lymphoma
Severe burns
Sickle cell disease
What nerve roots contribute to the ulnar nerve?
C7-T1
Presentation of ulnar nerve compression
Weakness/wasting of medial wrist flexors, interossei, medial lumbricals
Hypothenar eminence wasting
Weak 5th digit abduction and 4th and 5th DIP flexion
Sensory loss over medial 1.5 fingers and ulnar side of hand
Froment’s sign
Treatment of ulnar nerve compression?
Rest
Avoid pressure
Soft elbow splinting (if symptoms continue)
Hand splint- to prevent clawing
Surgery- if chronic associated with weakness/failure of splinting
Which nerve roots contribute to the radial nerve?
C5-T1
Presentation of radial nerve compression?
Wrist and finger drop with elbow fixed and arm pronated
Sensory loss is variable
Treatment of radial nerve compression?
Most resolve spontaneously
Lively splint may help to improve hand function during recovery
Which nerve roots contribute to the phrenic nerve?
C3-C5
Presentation of phrenic nerve compression?
Orthopnoea
Raised hemidiaphragm on CXR
Which nerve roots contribute to the common peroneal nerve?
L4-S1
Presentation of common perineal nerve compression?
Foot drop
Weak ankle dorsiflexion/eversion
Sensory loss over dorsal foot
Which nerve roots contribute to the tibial nerve?
L4-S3
Presentation of tibial nerve compression?
Inability to stand on tiptoe (loss of plantar flexion)
Inability to invert the foot or flex the toes
Sensory loss over sole
What is mononeuritis multiplex?
Involvement of ≥ 2 peripheral nerves in a mononeuropathy
Causes of mono neuritis multiplex?
Diabetes mellitus
Connective tissue disorders e.g. RA, SLE
Vasculitis
Rare: sarcoidosis, amyloid, leprosy
What is polyneuropathy?
Motor and/or sensory disorder of multiple peripheral or cranial nerves, usually symmetrical and widespread. Often worse distally
Broad causes of polyneuropathy?
Acquired
Hereditary
Demyelinating
Axonal
Acquired causes of polyneuropathy?
Dysmetabolic- diabetes Drugs- amiodarone, antibiotics, anti-retrovirals, chemotherapy, phenytoin Mechanical or compressive Cancer Immune related Toxins- alcohol, NO Infectious
Hereditary causes of polyneuropathy?
Hereditary motor and sensory neuropathy Hereditary neuropathy with liability to pressure palsies Familial brachial plexopathy Familial amyloidosis Prophyria MND
Demyelinating causes of polyneuropathy
Immune related- Guillain Barré syndrome Multiple compression neuropathies Drugs Lymphoma Severe burns Hereditary e.g.Charcot Marie Tooth 1, HNPP Sickle cell disease
Axonal causes of polyneuropathy?
Dysmetabolic- diabetes Immune/infectious- HIV, CMV, Lyme, Hepatitis C, leprosy Hereditary- Charcot Marie Tooth Post infectious- Guillain Barré syndrome Sarcoidosis Drugs and toxins e.g. alcohol Cancer Vasculitis
Which type of polyneuropathy can you treat?
Demyelinating ones
Which type of polyneuropathy can you not treat?
Axonal damage ones
Investigations into polyneuropathies?
Bloods: glucose, ESR, CRP, U&Es, LFTs, vitamin B12, folate Serum protein electrophoresis ANA, ANCA Chest X-ray HIV serology Others: vitamin E, vitamin A, genetic testing, lyme serology, serum ACE, serum amyloid Nerve conduction studies Electromyography
Causes of sensory polyneuropathy?
Diabetes mellitus
CKD
Leprosy
Alcohol
Presentation of sensory polyneuropathy?
Numbness Pins and needles Paraesthesia Glove and stocking distribution Difficulty handling small object Signs of trauma e.g. finger burns Joint deformation Diabetic and alcohol are painful
Cause of diabetic neuropathy?
Axonal degeneration
Patterns of diabetic neuropathy?
Distal symmetrical neuropathy
Asymmetrical proximal neuropathy
Autonomic neuropathy
Mononeuropathies and radiculopathies
Causes of motor polyneuropathy?
Guillain Barré syndrome
Lead poisoning
Charcot-Marie Tooth syndrome
Alcohol
Presentation of motor polyneuropathy?
Often progressive Weak or clumsy hands Difficulty walking- stumbling, falls Difficulty breathing Signs of LMN lesion
Guillain Barré syndrome mechanism for motor neuropathy?
Acute inflammatory demyelinating polyneuropathy
Presentation of motor neuropathy due to Guillain Barré syndrome?
Acute Varying severity A few weeks after infection a symmetrical ascending muscle weakness starts Sensory symptoms in legs and arms at onset Examination findings minimal May have pain in back, buttock, thigh Muscle weakness affects legs > arms Arreflexia
Treatment for motor neuropathy due to Guillain Barré syndrome?
Monitor vital capacity, if < 1 -> ventilation
Monitor for evidence of autonomic dysfunction
Monitor: pressure areas
Venous thrombosis prophylaxis
Chest and limb physiotherapy
Supportive care for paralysed patients
Shortening the disease course- plasma exchange, IV immunoglobulin
Causes of autonomic polyneuropathy?
Diabetes mellitus Guillain Barré syndrome Sjögren's syndrome HIV Leprosy SLE Toxic Genetic Paraneoplastic
Presentation of autonomic polyneuropathies?
Sympathetic: postural hypotension, decreased sweating, ejaculatory failure, Horner’s syndrome
Parasympathetic: constipation, nocturnal diarrhoea, urine retention, erectile dysfunction, Holmes-Adie pupil
Effects of alcohol and drugs?
Intoxication Dependence Withdrawal/DTs Seizures ARBD Wernicke's encephalopathyKorsakoff's Pellagra Blackouts Central pointine and extrapontine myelinolysis Marchiafava-Bignami disease Hepatic encephalopathy Neuropathy Ataxia
Treatment of alcohol dependence?
Antabuse
Acamproate
Naltrexone
Baclofen
What two systems are within the UMN?
Cortico-spinal system
Cortico-bulbar system
Function of the cortico-bulbar system?
Controls the cranial LMNs
Function of the cortico-spinal system?
Control the spinal LMNs
What is the portico-spinal system also called?
The pyramidal system
Third nerve palsy presentation?
Eye down and out
Ptosis
Mydiasis (pupil dilated)
Sixth nerve palsy presentation?
Esotropia (one/both eyes turn in)
Diplopia (double vision)
Seventh nerve palsy (Bell’s palsy) presentation?
One sided facial droop