Summary Book Neurology Flashcards
What is the anatomical structures of the upper motor neuron pathway?
Cerebrum Hemispheres, Cerebellum, Brain Stem, Spinal Cord
What is the anatomical structures of the lower motor neuron pathway?
Anterior Horn Cell, Roots, Nerves, Neuromuscular Junction, Muscles
What neurological deficits are seen with issues with the cerebrum hemispheres?
Contralateral motor and sensory loss
What neurological deficits are seen with issues with the cerebellum?
Ipsilateral past-pointing and ataxia, as well as nystagmus
What neurological deficits are seen with issues with the brain stem?
Autonomic features, cranial nerve palsy, crossed limb signs
What neurological deficits are seen with issues with the spinal cord?
If cervical then bilateral upper and lower limbs affected, if thoracolumbar then bilateral lower limbs and if conus medullaris then bilateral lower limb with bladder and bowel dysfunction
What neurological deficits are seen with issues with the anterior horn cells?
Mixed upper and lower features in same region
What neurological deficits are seen with issues with the roots?
Ipsilateral, single limb involved with lower motor signs and often painful
What neurological deficits are seen with issues with the nerve plexus?
Ipsilateral, single limb, painful, not attributable to single nerve or level
What neurological deficits are seen with issues with the peripheral nerve?
Discrete deficit in one limb, one dermatome
What neurological deficits are seen with issues with the neuromuscular junction?
Generalised weakness, fatigable on repetitive testing, minimal sensory involvement
What neurological deficits are seen with issues with the muscles?
usually symmetrical in all limbs, sometimes with wasting, pattern usually proximal / limb girdle or distal
Conditions which affect the cerebrum hemispheres?
Stroke, MS, cerebral abscess, AVM, tumour
Conditions which affect the cerebellum?
Alcohol, stroke, AVM, tumour, paraneoplastic, sarcoidosis, multiple sclerosis, vitamin B12 deficiency, multiple system atrophy, congenital (spinocerebellar ataxia - dominant, Fredrich’s ataxia - recessive)
Conditions which affect the brain stem?
Stroke, MS/NMOSD, Bickerstaff
Conditions which affect the cervical spinal cord?
Trauma, MS/NMOSD, syringomyelia, cord compression, stroke
Conditions which affect the thoracolumbar spinal cord?
Trauma, compression, cord stroke, epidural abscess
Conditions which affect the conus medullaris?
Trauma, malignant cord compression, abscess
Conditions which affect the anterior horn cells?
MND, past polio
Conditions which affect the roots?
Degenerative disease, malignant compression
Conditions which affect the nerve plexus?
Trauma, malignant infiltration, paraneoplastic, inflammatory
Conditions which affect the peripheral nerve?
Extrinsic compression, metabolic, endocrine, toxic, drug, induced, vasculitis
Conditions which affect the neuromuscular junction?
Drug induced, MG, ES
Conditions which affect the muscles?
Myositis, muscular dystrophy, acquired myopathy, metabolic / mitochondrial myopathy
Upper motor neuron signs
Increased tone, clonus, increased reflexes, upgoing plantar
Lower motor neuron signs
Decreased tone and reflexes
Which cranial nerves enter the midbrain?
3 and 4
Which cranial nerves enter the pons?
5, 6, 7 and 8
Which cranial nerves enter the medulla?
9, 10, 11 and 12
Define Neuromyelitis Optica Spectrum Disorder
Inflammation of CN2, with painful eye movements, AQP4/MOG positive
Investigations for myopathies
Autoimmune screen + anti-Jo1 + biopsy of muscle
Causes of myopathies
Inflammatory (inclusion body myositis, sarcoidosis), Autoimmune (dermatomyositis, polymyositis), Metabolic (alcohol), Neoplastic, Degenerative (critical illness), Iatrogenic (steroids, statins), Congenital (Becker muscular dystrophy, Duchenne’s muscular dystrophy, myotonic dystrophy, facioscapulohumeral, limb girdle), Endocrine (acromegaly, thyroid issues, hypercortisolism)
Key sign of Duchenne’s muscular dystrophy
Calf pseudohypertrophy
Key signs of Muscular dystrophy
Myotonia, frontal bossing, ptosis
Two categories of peripheral neuropathy
Axonal (75%) and Demyelinating
Features of demyelinating peripheral neuropathy
Proximal predominant, neuropathic tremor, loss of proprioception, muscle wasting
General causes of peripheral neuropathy
Compression, diabetes, EtOH, uraemia, heavy metal, paraneoplastic, vitamin B12 deficit, congenital (charot mary tooth), iatrogenic (chemotherapy), infective (Guillain barre syndrome), inflammatory (sarcoidosis) and autoimmune (polyarteritis nodosa, systemic lupus erythematous, rheumatoid arthritis)
Causes of painful peripheral neuropathy
Vitamin B deficiency, heavy metal, paraneoplastic
Nerves of pectoralis
pectoral, C6, c7, c8
Nerves of tricep
radial, c6, c7, c8
Nerves of bicep
musculocutaneous, c5, c6
Nerves of brachioradialis
medial, c5, c6
Nerves of flexor digitorum
median and ulnar, c7, c8, c9
Nerves of adductor
obturator, l2, l3, l4
Nerves of knee - quadriceps femoris
femoral, l2, l3, ;4
Nerves of ankle - soleus / gastrocnemius
sciatic / tibial, s1, s2
Nerves of plantar
plantar
Causes of bilateral foot drop
motor neuron disease, hereditary neuropathy (charot marie tooth), hereditary motor dystrophy (myotonic)
Presentation of foot drop due to common peroneal
inversion preserved, sensory loss of dorsum of foot, reflexes normal
Presentation of foot drop due to L5 root nerve palsy
inversion preserved, sensory loss of dorsum of foot, reflexes normal, weakness of hip extension / knee flexion / inversion and eversion of ankle, decreased sensation of lateral calf and dorsum of foot
Presentation of foot drop due to sciatica (l4,5) (s1,2)
weakness of knee flexion and below knee, no ankle jerk, decreased sensation of lateral thigh and below knee
Presentation of foot drop due to femoral nerve palsy (l2,3,4)
weakness of knee extension and hip flexion, decreased sensation of inner thigh, decreased knee flexion
Presentation of motor neurone disease
upper and lower motor neurone signs in same region, initially asymmetric weakness confined to one segment, late signs of respiratory muscle weakness and cardiomyopathy, 25 to 40% cognitive features with frontotemporal behaviour and executive dysfunction, sensory exam unremarkable
Signs of pseudo bulbar disease
upper motor neuron, laryngospasms, trismus, brisk jaw jerk, small spastic tongue, slow + monotonous speech, emotional lability
Signs of bulbar disease
lower motor neuron, dysarthria, dysphagia, flaccid tongue, nasal twang
5 types of motor neuron disease syndromes
- Primary Lateral sclerosis (isolated UMN), 2. Progressive Muscular Atrophy (isolated LMN), 3. Progressive Bulbar Palsy (U + LMN disorder of cranial nerves), 4. Flail Arm / Leg Syndrome (progressive LMN weakness of proximal arm and distal leg), 5. ALS (amyotrophic) plus - plus atypical features (pain, ocular motility disturbance, tremor, extra-pyramidal symptoms (akathisia = urge to move, tardive dyskinesia = involuntary movement, dystonia = involuntary muscle contraction, parkinsonism), ataxia, autonomic dysfunction
Causes of acute mononeuritis multiplex
diabetes mellitus, vasculitis (systemic lupus erythematous, polyarteritis nodosa (medium vessel), rheumatoid arthritis)
Causes of chronic mononeuritis multiplex
infection (leprosy), multiple compressive neuropathies, sarcoidosis
Examination findings for myotonic dystrophy
hand (finger grip, percussion myotonia, repeated grip improves), face (frontal balding, cataracts, temporal-mandibular wasting, ptosis), neck (decreased muscle power and rom), cardio (conductive defects - PPM, displaced apex - cardiomyopathy), hypogonadism - gynaecomastia
First cranial nerve
olfactory - smell
Second cranial nerve
optic - vision
Third cranial nerve
Oculomotor - pupil constriction, accommodation, moves eyes up / down / medially, opens eyelids
Fourth cranial nerve
trochlear - supplies superior oblique muscle - moves eye down and inward
Fifth cranial nerve
trigeminal - sensation to face, muscles of mastication
Sixth cranial nerve
abducens - supplies lateral rectus - moves eye laterally
Seventh cranial nerve
facial - supplies muscles of facial expression, taste (anterior 2/3), closes eyelids
Eight cranial nerve
Vestibulocochlear - hearing and balance
Nineth cranial nerve
Glossopharyngeal - taste (posterior 1/3), swallowing and salivation
Tenth cranial nerve
Vagus - parasympathetic supply to eye / heart / gut / lungs / larynx (vocal cords)
Eleventh cranial nerve
Accessory - sternocleidomastoid and trapezius
Twelfth cranial nerve
Hypoglossal - tongue muscles
Causes of positive jaw jerk reflex (deviates to weakness)
Peripheral - shingles and Sjogren’s, Central - MS, cerebellopontine angle tumour (acoustic neuroma, meningioma)
Which nerves travel through the cerebellopontine angle?
5,6,7,8
Sounds for testing lip, tongue and vocal cord function
lip = me, tongue = la, vocal cord = ee
Causes of unilateral ptosis
congenital, Horner’s, myasthenia gravis, third nerve palsy
Causes of bilateral ptosis
congenital, Horner’s, myasthenia gravis, myotonic dystrophy, neurosyphilis
Sign of positive relative afferent pupillary defect
dilation with direct light
Retinal causes of relative afferent pupillary defect
infective (CMV, HSV), neoplastic (melanoma), structural (detachment), vascular (ischaemic diabetic retinopathy; or central artery or vein occlusion)
Optic causes of relative afferent pupillary defect
glaucoma, optic neuropathy