Neurology Flashcards
Where test sensation in upper limbs - which dermatome is which?
in anatomical position
C5 = lat upper arm
C6 = lat lower arm
C6/median = lat index
C7 = middle finger
C8/ulnar = medial palm
C8 = med lower arm
T1 = med upper arm
turn hands over
radial = dorsal web
glove = back finger up
Where test sensation in lower limbs - which dermatome is which?
L2 = midpoint thigh
L3 = patella
L4 = medial calf
L5 = lateral calf
S1 = lat top foot
stocking = big toe up
Which movements in upper limb correspond to which myotome (nerve routes & peripheral nerves)?
Shoulder aBduction (C5)
Elbow flexion (C5-7, musculocutaneous nerve)
Elbow extension (C7-8, radial nerve)
Wrist extension (C7, radial nerve)
Grip (finger flexion, C8-T1, median & ulnar nerves).
Finger extension (C7, radial nerve)
Finger abduction (T1, ulnar nerve).
Thumb abduction (T1, median nerve)
Which movements in upper limb correspond to which myotome (nerve routes & peripheral nerves)?
Hip flexion (L1-3; femoral nerve)
Hip extension (L5-S2)
Knee extension (L3-4; femoral nerve)
Knee flexion (L5-S1; sciatic nerve)
Ankle dorsiflexion (L4-5; common peroneal nerve (CPN), a branch of the sciatic)
Ankle plantarflexion (S1-2; tibial nerve, a branch of the sciatic)
Ankle eversion (L5-S1; CPN; peroneus longus & brevis)
Tested in foot drop along with inversion to distinguish a CPN (foot drop & weak eversion) from L5 root lesion (foot drop, weak eversion & inversion)
Ankle inversion (L4-5; tibial nerve; tibialis posterior)
Big toe extension (L4-5; CPN; extensor hallucis longus)
Causes of myotonia 4
Myotonia congenita (Thomsen’s disease, Becker’s disease)
Paramyotonia congenita
Hypokalaemic periodic paralysis
Drugs: Clofibrate
DDx of distal wasting + weakness 4
HSMN (Charcot-marie-tooth)
Distal Spinal muscular atrophy
Inclusion-body myositis
Oculopharyngeaodistal myopathy
Causes of ptosis
6 bilateral, 2 unilateral
Bilateral: Myotonic dystrophy, myasthenia gravis, congenital, senile, mitochondrial cytopathies, bilateral Horner’s syndrome
Unilateral: CN III palsy, Horner’s syndrome
Causes of UNILATERAL cerebellar syndrome (4 ischaemic, 3 neoplastic)
Ischaemic: Cerebellar hemisphere stroke, lateral medullary syndrome, lacunar infarct, vertebral artery dissection
Neoplastic: Cerebellopontine angle tumour, cerebellar tumour/met, NF2
Causes of BILATERAL cerebellar syndrome (5 hereditary, 3 inflammatory/degenerative, 6 drug/toxin, 1 ischaemic, 4 neoplastic)
Hereditary: Friedreich’s ataxia, ataxic telangiectasia, spinocerebellar ataxia, Wilson’s disease, Arnold-Chiari malformation
Inflammatory: MS, Miller-Fischer syndrome, MSA (degen.)
Drug-induced: Alcoholic cerebellar degeneration, Wernicke’s encephalopathy, phenytoin, lithium, carbamazepine, phenobarbitone
Ischaemic bilateral cerebellar strokes
Neoplastic: Bilateral cerebellopontine angle tumours, NF2, VHL syndrome, paraneoplastic from lung/breast/ovarian cancer
?also vit A & E?
MRC power grades
0 None
1 Flicker
2 Moves with gravity neutralised
3 Moves against gravity
4 Reduced power against resistance
5 Normal
Causes of lower limb spasticity? 12 (some v rare….)
MS
Spinal cord compression, cervical myelopathy
Trauma
MND
ASA thrombosis
Syringomyelia
Hereditary spastic paraplegia
Tropical spastic paraparesis
SCDC (Subacute combined degeneration of spinal cord)
Friedreich’s ataxia
Parasagittal falx meningioma
Primary lateral sclerosis
Causes of cord compression 5
Disc prolapse
Malignancy
Infection: Abscess, TB
Trauma: Vertebral fracture
Lower limb reflexes - which spinal level
Knee jerk L3/4
Ankle jerk S1/2
Upper limb reflexes - which spinal level
Biceps and supinator C5/6
Triceps C7/8
3 types of MND
Amyotrophic lateral sclerosis (50%)
Progressive muscular atrophy (25%)
Progressive bulbar palsy (25%)
Causes of generalised wasting of hand muscles
(4 anterior horn cell, 3 brachial plexus, 2 peripheral nerve, 1 muscle)
Anterior horn cell: MND, syringomyelia, cervical cord compression, polio
Brachial plexus: Cervical rib, pancoast tumour, trauma
Peripheral nerve: Combined median and ulnar nerve lesions, peripheral neuropathy
Muscle: Disuse atrophy e.g. RA
DDx of pure LMN signs (4 benign fasiculations, 8 other)
Benign fasciculations (thyrotoxicosis, alcohol, exercise, caffeine)
Cramp-fasciculation syndrome
Multifocal motor neuropathy with conduction block
Brachial neuritis
Spinobulbar muscular atrophy (Kennedy’s disease)
Motor-predominant CIDP
Inclusion-body myositis
Spinal muscular atrophy
Post-polio syndrome
DDx of mixed UMN + LMN signs (extensor plantars with absent knee jerks) 7
MND
Friedreich’s ataxia
SCDC (vitamin B12 deficiency)
Vitamin E deficiency
Taboparesis (tertiary syphilis)
Conus medullaris lesion
Combined pathology
Other mixed: Cervical myelopathy, syringomyelia
DDx of myelopathy / pure UMN signs
(3 compression, 3 autoimmune, 3 infections, 2 nutritional, 2 genetic)
Compression: Disc herniation, tumours (intra/extra-medullary, primary/secondary), spinal stenosis
Autoimmune: MS, lupus, sarcoid
Infections: HIV, VZV, HLTV1
Nutritional: Vitamin B12, Cu
Genetic: Hereditary spastic paraparesis, primary lateral sclerosis
Aside from spinal, other causes of pure UMN: 2 cortical, 1 infection, 2 deyelinating
Cortical: Stroke (ischaemic, haemorrhagic), SOL
Spinal: See prev card
Infection: Cortical/spinal
Demyelinating: MS (cortical/spinal), transverse myelitis (spinal)
parkinsonism definition
Bradykinesia + 2 of:
Rigidity
Resting tremor
Postural instability
Causes of parkinsonism (5 low dopamine, 3 normal dopamine)
Low dopamine:
- PD
- PSP, early falls, vertical gaze palsy (speed reduces then amount), symmetrical, mild tremor
- CBD - alien limb, pain, one sided, rapid onset, very high tone (may need botox)
- MSA: bowel/bladder, postural hypotension, erectile dysfunction, cerebellar dysfunction
- lewy body dementia (no response to tx, early cog dysfunction & hallucinations - often scary)
Normal dopamine:
- Drug-induced (symmetrical)
- Vascular - lower limbs predominant & symmetrical
- Wilsons
Parkinsons treatment options (4 first line groups, 3 advanced treatments, 2 for hallucinations)
give drug examples
L-dopa + peripheral Dopa-decarboxylase inhibitor (co-careldopa, co-beneldopa)
COMT inhibitors (entacapone, tolcapine)
Dopamine agonists (pergolide, cabergoline, bromocriptine, apomorphine, pramipexole, ropinorole, rotigotine)
MAO-B inhibitors (selegiline, rasagiline)
advanced: duodopa jej, apomorphine infusion, DBS
For disturbing hallucinations:
- quetiapine if normal cognition
- rivastigmine if reduced cognition
Four different types of tremor types of causes
Essential
Bilateral - hands, feet, head
Action (and at rest)
Worse when stressed
Better with alcohol
50% have family hx
Cerebellar
Unilateral / bilateral
Worse on intention
PD
Asymmetrical
Resting pill rolling tremor
Worse with distraction, stress, emotion (can also get re-ermergent)
Enhanced physiological
Fine tremor of both hands
Reversible
Alcohol withdrawal, drugs, thryoid
Causes of peripheral neuropathy
DANG THERAPIST is acronym
DANG THERAPIST
Diabetes - commonest (typically sensory predominant)
Alcohol
Nutritional (incl B12 - nb dif from subacute deden which is UMN), B1 & B6
Guillain barre
Toxins (chemo, drugs, amiodarone, abx)
Hereditary (eg charcot marie tooth) - look for features of chronicity - eg pes cavus
Environmental (lead - motor predominant) or NOS
Relapsing neuropathies - CIDP
Amyloidopathy (hereditary & acquired)
Paraproteinaemia
Infectious (HIV, syphillis, leprosy - thickened palpable peripheral nerve w leprsoy)
Systemic (hypothyroidism, uraemia)
Tumours (nerve sheath tumours, paraneoplastic syndrome)
Causes of predominantely sensory peripheral neuropathy? 4
Friedreich’s ataxia
Drugs (chemotherapy)
Sjogren’s syndrome
Paraneoplastic
Causes of mixed sensory and motor peripheral neuropathy 9 (some are groups)
DM
Alcohol
Nutritional deficiencies (vitamin B1/6/12, folate)
Hypothyroidism
HSMN
Drugs: Metronidazole, nitrofurantoin, isoniazid, vincristine, dapsone
Endocrine/metabolic: Hypothyroidism, uraemia, liver failure
Infection: HIV, HSV
Inflammatory: GBS (acute), CIDP (chronic), vasculitis
Causes of predominantly motor peripheral neuropathy
(7 nerve, 1 NMJ, 1 muscle)
Nerve: Inflammatory (GBS, CIDP, MGUS); Other (heavy metals e.g. lead, diabetic amyotrophy, inherited distal motor neuropathy, SMA)
NMJ: MG
Muscle: Myotonic dystrophy
Causes of mononeuritis multiplex (2 CTDs, 5 vasculitis, 3 infection, 2 other)
DM
CTDs: RA, SLE
Vasculitis: PAN, GPA, eGPA, SS, SLE
Infections: HIV, Lyme disease, leprosy
Paraneoplastic
Causes of extensor plantars with absent knee jerks 6
Friedrech’s ataxia
SCDC
MND
Taboparesis
Conus medullaris lesions
Combined upper and lower pathology
