Neurology Flashcards
Features of Parkinsons disease
- Hypomimia
- Masked facies
- Slow blink rate (glabella tap)
- Hypophonia
- Gait - stooped, reduced arm swing (often asymmetric), short stride length/shuffling + note tremor –> festination, freezing, turning en bloc + multiple steps to turn
- Tremor - rest, asymmetric pill rolling - comfortable posture + distract (eyes closed, count backwards)
- Rigidity - cogwheeling, lead pipe (increase with coactivation; head turning, painting a wall)
- Bradykinesia with decrement
- May have duodopa running through PEG-J or subcut apomorphine pump); look for DBS battery
- Other exam:
- EOM (vertical first, PSP)
- Cerebellar signs (MSA), lying/standing BP, postural instability
- Other: writing (micrographia), Archimedes spiral (tremor), cognitive Ax (DLB)
DDx Parkinsons
- Drug induced PSP - impaired vertical gaze
- MSA
- DLB
- CBD
- Vascular parkinsonism
- Normal pressure hydrocephalus
Ax: Drug history MRI (if atypical features) Trial of levodopa
Features of Charcot Marie Tooth Disease (Hereditary Motor and Sensory Neuropathy)
- Pes cavus (short high arched feet with hammer toes)
- Distal muscle atrophy (from peripheral generation) –> inverted champagne bottle leg
- Does not extend above the elbows or above the middle one third of the thighs
- Areflexia/hyporeflexia (always show reinforcing manoeuvres)
- Slight or not sensory deficits in the limbs
- Thickened nerves
- Foot drop –> high stepping gait, look for AFOs/Dictus bands
Bedside: opthalmoscope (optic atrophy)
Ix: NCS, genetics (PMP22), OT for functional assessment
Differentials for Pes Cavus
- Charcot Marie Tooth
- Fredrichs ataxia
- Spina Bifida
- Long standing neuropathy –> cerebral palsy, muscular dystrophy, old polio, spinal muscular atrophy etc,
Ax: family history, neuropathy screen, NCS (axonal vs demyelinating), genetics
Features of Facioscapulohumeral (FSHD) Muscular Dystrophy
- Often asymmetric
- Polyhill sign (deltoid typically spared)
- Remember to test scapular winging: flexion + wall press
- Limited abduction + flexion
- Subtle facial weakness (ask pt to whistle, close eyes tightly, puff out cheeks)
DDx: other muscular dystrophies (LGMD etc), MG, DM, mitochondrial myopathies
Ax/Ix: FHx, CK, EMG, genetics
Majority AD
Features of Myotonic Dystrophy
- Frontal balding
- Bilateral partial ptosis
- Dull triangular facies
- Wasting of temporalis, masseter and sternomastoid atrophy
- Fine subscapular deposits
- PPM
- Upper limbs
- Wasting of small muscles of hands
- Long finger flexors early (uncommon) - test specifcially
- Grip myotonia (shake hands)
- Percussion myotonia
- Should not have sensory loss
- Testicular atrophy
- Associations: DM, cardiomyopathy
DDx: T1MD, T2MD, myotonia congenita, paramyotonia congenita
Ax/Ix: FHx, CK, EMG, genetics, RFTs/sleep study, ECG/TTE
AD inheritance, anticipated (particularly maternal transmission)
sporadic Inclusion Body Myositis
- Distinctive pattern
- Early involvement of long finger flexor + quadriceps (then ankles dorsiflexors)
- Relative preservation of flexion at MCPJs (lumbricals) - test long finger flexors specifically!
- Dysphagia (look for PEG)
- (facial weakness can occur)
DDx: muscular dystrophy, myopathy, DM
Ax/Ix: CK, EMG, muscle biopsy, anti-cN1a/NT5C1A
Features of Fredreich’s Ataxia
Autosomal recessive
- Cerebellar signs (bilateral) including nystagmus
- Posterior column loss in the limbs (vibration/proprioception loss)
- UMN Sx in limbs (but absent ankle jerks)
- Peripheral neuropathy
- Pes cavus/hammertoes/kyphoscoliosis
- Optic atrophy
- Cardiomyopathy (usually LVH)
- Diabetes mellitus
- Hearing loss
DDx: MS, acquired ataxia (ETOH/structural), spinocerebellar ataxia, neuropathies, spinal cord lesions etc
Ax: family history, ETOH, neuropathy screen, MRI (brain and spine), genetics
Features of Hereditary Spastic Paraparesis
- Progressive LL spasticity +/- weakness
- Hyper-reflexia, clonus, extensor plantar
- Concomitant dorsal column deficits (no pinprick level/touch)
- Pes cavus (sometimes)
DDx: cerebral palsy, spinal cord pathology, MS, MND, SCDC, TSP, HIV, syphilis, FA, X-ALD etc
Ix: FHx, MRI (spine +/- brain), myelopathy screen, genetics
Features of Motor Neurone Disease
- Combinattion of UMN + LMN
- UL/LL, respiratory muscles, bulbar muscles (look for PEG)
- Sensation and bowel/bladder usually preserved
- Split hand sign - thenar muscles disproportionally wasted to hypothenar
- Check tongue fasciculations/wasting + jaw jerk
- Pseudobulbar affect - inappropriate/excessive laughing or crying)
- Consider FTD
DDx: cervical cord lesion, spinal muscular atrophy, paraneoplastic, HSP, Kennedy Disease
Ax: FHx, CK, NCS/EMG, MRI C-spine (often), consider genetic testing
Features of Kennedy’s Disease
X-Linked (men only)
- LMN - can be asymmetric
- Gynaecomastia
- Prominent bulbar involvement
- Perioral fasciculations
- Tongue wasting
- Subtle distal sensory deficits
Ax: FHx, CK, genetics
Causes of Peripheral Neuropathy
“DAM IT BICH”
- Drugs & toxins: isoniazid, vincristine, phenytoin, nitrofurantoin, cisplatin, amiodarone, large dose B6, heavy metals
- Alcohol
- Metabolic - DM, uraemia, hypothyroidism, porphyria
- Immune-mediated - GBS
- Tumour - lung ca (paraneoplastic)
- Vitamin B12, B1, B5, B6 deficiency
- Idiopathic
- Connective tissue disease/vasculitis - SLE, PAN
- Hereditary
30% DM, 30% hereditary, 30% idiopathic
Causes of Predominant Sensory Neuropathy
“BD TIPS”
- B6 intoxication/B12 deficiency
- Diabetes
- Tumour - lung/ovary/breast
- Idiopathic
- Paraproteinaemia
- Sjogrens/Syphilis
Causes of Painful Peripheral Neuropathy
“DAVP ACTH”
- Diabetes mellitus
- Alcohol
- Vitamin B12/B1 deficiency
- Porphyria
- Arsenic poisoning
- Carcinoma
- Thallium poisoning
- Hereditary (usually not painful)
Causes of Mononeuritis Multiplex
Acute
- Vascular
- Diabetes mellitus
- PAN
- CT disease - SLE/RA
Chronic
- Multiple compressing neuropathies - particularly with joint deforming arthritis
- Sarcoidosis
- Acromegaly
- Leprosy
- Carcinoma (rare)
- Idiopathic
Complete Brachial Plexus Injury
- Complete sensory loss
- LMN of whole arm
- Horner’s syndrome (if proximal in lower plexus –> T1)
Assess for axillary lymphadenopathy
Upper Trunk (C5/C6) lesion
- Loss of shoulder movement and elbow flexion –> waiter’s tip
- Sensory loss - lateral aspect of arm and forearm and over thumb
Lower Trunk (Klumpke’s) Lesion
- True claw hand with paralysis of intrinsic muscles
- Sensory loss along ulnar side of hand and forearm
- Horner’s syndrome
Features of Radial Nerve Palsy
- Wrist and finger drop (preserved wrist flexion)
- Triceps loss (elbow extension) is above the spiral groove
- Sensory loss over anatomical snuff box
- Finger abduction appears to be weak as cannot straighten the fingers
Features of Median Nerve Palsy and causes of Carpal Tunnel Syndrome
- Pen touching test –> ask to abduct thumb vertically to touch pen (loss of abductor pollicis brevis)
- Ochsner’s Clasping test –> clasp hands firmly together (index finger fails to flex) (loss of flexor digitorum sublimis)
- Sensory loss –> thumb, index, middle and lateral half ring finger palmar aspect
Causes of Carpal Tunnel
- Idiopathic
- Arthropathy - rheumatoid arthritis
- Endocrine - hypothyroidism, acromegaly
- Pregnancy
- Trauma and overuse
Features of Ulnar Nerve Palsy
- Wasting of intrinsic muscle of the hand (except LOAF)
- Weak finger abduction and adduction (loss of interosseous muscles)
- Ulnar claw-like hand
- Froment’s sign - ask patient to grasp a piece of paper between the thumb and lateral aspect of forefinger (affected thumb with flex - loss of thumb adductor)
- Sensory loss over the little and medial half of the ring finger (both palmar and dorsal aspect)
Features of Femoral Nerve Lesion
- Weakness of knee extension (quadriceps paralysis) and slight hip flexion weakness
- Loss of knee jerk
- Preserved adductor strength
- Sensory loss of inner aspect of thigh and leg
Features of Sciatic Nerve Lesion
- Weakness of knee flexion (hamstrings)
- Loss of power of all muscles below knee (can walk but cannot stand on toes or heels)
- Knee jerk intact, loss of ankle and plantar response
- Sensory loss along posterior thigh and total loss below the knee
Features of Common Peroneal Lesion
- Foot drop and loss of foot eversion only
- Sensory loss (minimal) over dorsum of foot
- Reflexes normal
Causes of Foot Drop
- Common peroneal nerve palsy
- Sciatic nerve palsy
- Lumbosacral plexus lesion
- L4/L5 root lesion
- Peripheral motor neuropathy
- Distal myopathy
- Motor neurone disease
- Precentral gyrus lesion
Test ankle jerk –> if absence, S1 lesion suspected; if normal common peroneal; if increased UMN/MND
Inversion is noraml in common peroneal but absent in L5 radiculopathy (eversion is absent in both)
Causes of Horner’s Syndrome
- Carcinoma of the lung apex (usually squamous cell carcinoma)
- Neck - thyroid malignant, trauma
- Carotid arterial lesion - carotid aneurysm/dissection, pericarotid tumour, cluster headache
- Brain stem lesions - vascular disease (especially lateral medullary syndrome), syringobulbia, tumour
- Retro-orbital lesions
- Syrindomyelia (rare)
Causes of 3rd Nerve Palsy
Central
- Vascular (eg brain stem infarction)
- Tumour
- Demyelination (rare)
- Trauma
- Idiopathic
Peripheral
- Compressive lesion
- Aneursym (PCOM)
- Raised ICP from tumour
- Nasopharyngeal carcinoma
- Orbital lesions - Tolosa-Hunt syndrome (superior orbital fissure syndrome; painful lesion of 3rd, 4th, 6th and first division of 5th cranial nerve)
- Basal meningitis
- Infarction (DM, arteritis) (pupil usually spared)
- Trauma
- Cavernous sinus lesion
Features of 3rd Nerve Palsy
- Complete ptosis (partial ptosis can occur with incomplete lesion) 2. Divergent strabismus (down and out) 3. Dilated pupil unreactive to direct/consensual light and unreactive to accomodation Exclude 4th nerve by tilt patient head to same side as lesion (will intort if intact) or ask patient to look down and across to opposite side of lesion
Causes of 6th Nerve Palsy
- Bilateral
- Trauma (head injury)
- Wernicke’s encephalopathy
- Raised ICP
- Mononeuritis multiplex
- Unilateral
- Central
- Vascular
- Tumour
- Wernicke’s encephalopathy
- Multiple sclerosis (rare)
- Peripheral
- Diabetes, other vascular lesions
- Trauma
- Idiopathic
- Raised ICP
- Central
Features of a 6th Nerve Palsy
- Failure of lateral movements
- Affected eye is deviated inwards in severe lesions
- Diplopia - maximal on looking to the affected side
- Images are horizontal and parallel to each other
- Outermost image is from the affected eye and disappears when covering this eye
Causes of nystagmus
Horizontal
- Vestibular
- Fast phase away from the side of the lesion
- Cerebellar
- To side of lesion
- Drift is towards midline with fast phase in direction of gaze
- INO
- Failure of adduction of affected side with nystagmus in the abducting eye
Vertical
- Brain stem
- Upbeat - lesion in floor of fourth ventricle
- Downbeat - forament magnum lesion
- Toxic - phenytoin, alcohol
Causes of 5th Nerve Palsy
Central (pons, medulla, upper cervical cord)
- Vascular
- Tumour
- Syringobulbia
- Multiple Sclerosis
Peripheral (posterior fossa)
- Aneurysm
- Tumour (eg skull base - eg acoustic neuroma)
- Chronic meningitis
Cavernous Sinus (associated 3rd/4th/6th)
- Aneurysm
- Thrombosis
- Tumour
Trigeminal Ganglion (petrous temporal bone)
- Meningioma
- Fracture of middle fossa
Other
- Sjogren’s syndrome
- SLE
- Toxins
- Idiopathic
Subacute Combined Degeneration of the Cord
- Symmetrical posterior column loss (vibration and proprioception) –> ataxic gait
- Symmetrical UMN in lower limbs with absent ankle reflexes
- Peripheral sensory neuropathy
- Optic atrophy
- Dementia
Causes of Myelopathy
Compressive
- Syringomyelia
- Spondylotic myelopathy (disc prolapse)
- Neoplasm
- Abscess
Inflammatory
- Transverse myelitis
- Connective tissue disease
- MS
- NMO
- Sarcoidosis
- Paraneoplastic syndrome4
Infection
- Epidural abscess
- Acute viral myelitis (enterovirus, flavivirus)
- AIDS myelopathy
- Syphilis (dorsal column)
Vascular
- Spinal cord infarction
- Vascular malformation
- Epidural haematoma
Toxic
- Subacute combined degeneration
- Radiation myelopathy
- Intrathecal chemotherapy
Causes of Myopathy
- Hereditary muscular dystrophy
- Congenital myopathies
- Acquired (PACE PODS)
- Polymyositis or dermatomyositis
- Alcohol
- Carcinoma
- Endocrine (hypothyroidism, hyperthyroidism, Cushing’s syndrome, acromegaly, hypopituitarism)
- Periodic paralysis (potassium)
- Osteomalacia
- Drugs (eg steroids)
- Sarcoidosis or connective tissue disease
Tests
- CK
- EMG
- ECG
- Muscle biopsy
- TTE
Muscular Dystrophy
Duchenne’s (pseudohypertrophic) (X-linked recessive)
- Affects only males
- Calves and deltoids are hypertrophied early and weak later
- Early proximal weakness
- Tendon reflexes preserved in proportion to muscle strength
- Severe progressive kyphoscoliosis
- Dilated cardiomyopathy
- CK high
Becker’s
- Less severe than Duchenne’s
- Later onset and less rapidly progressive
Limb Girdle (autosomal recessive)
- Shoulder or pelvic girdle affected
- Face and heart spared
Facioscapulohumeral (autosomal dominant)
- Facial and pectoral girdle weakness
- Hypertrophy of the deltoids
Distal Dystrophies
- Myotonic dystrophy
Myotonic Dystrophy
- Frontal balding
- Dull triangular facies
- Temporalis, masseter and sternomastroid atrophy
- Partial bilateral ptosis
- Neck - SCM atrophy; flexion weak, extension normal
- UL
- Grip myotonia (shake hands)
- Percussion myotonia (tap over thenar eminence –> contraction then slow relaxation of abductor pollicis brevis)
- Wasting and weakness; especially of forearm muscles
- Sensory changes with peripheral neuropathy
- Gynaecomastia
- LL if time
- Test urine for sugar and CVS for cardiomyopathy
- EMG: dive bomber effect with needle movement in muscle at rest
Causes of Chorea
- Hungtington’s disease (autosomal dominant)
- Sydenham’s chorea (rheumatic fever)
- Senility
- Wilson’s disease
- Drugs (eg OCP, phenytoin, L-dopa)
- Vasculitis
- Thyrotoxicosis
- Polycythaemia and other causes of hyperviscosity
- Viral encephalitis (rare++)
