Neurological Flashcards
Important points to cover in cerebellar examination?
DANISH
- Dysdiadochokinesia
- Ataxia (gait and posture)
- Nystagmus
- Intention tremor
- Slurred, staccato speech
- Hypotonia/heel-shin test
Clinical signs in cerebellar exam?
- Abnormal posture
- Speech abnormalities
- Scars
- Gait
Objects or equipment in cerebellar exam?
- Walking aids
- Hearing aids
- Prescriptions
Truncal ataxia?
Affects proximal musculature that is involved in gait stability - caused by damage to cerebellar vermis and associated pathways
Appendicular ataxia?
- Affects musculature of the arms and legs involved in the control of limb movement - caused by damage to cerebellar hemispheres
What are you assessing the patients gait for in a cerebellar exam?
- Stance
- Stability
- Turning
Tandem gait - sensitive to identify?
Dysfunction of the cerebellar vermis (eg. alcohol induced cerebellar degeneration)
Causes of cerebellar degeneration?
- Chronic alcohol misuse
- Nutritional deficiency (typically B12)
- Paraneoplastic disorders
- neurological diseases (eg. MS, spinocerebellar ataxia)
Clinical features of cerebellar degeneration
- Broad- based ataxic gait
- Truant ataxia
- Dysmetria
- Nystagmus
Rombergs test - deficit in?
proprioception or vestibular function (opposed to cerebellar dysfunction)
How can ataxic dysarthria present?
- Scattato speech (broken into syllables)
- Slurred speech
Gaze disturbances in cerebellar exam?
- Nyastagmus
- Dysmetric saccades
- Impaired smooth pursuit
Further investiagiotn and assessment after cerebellar exam?
- Full neurological exam (cranial nerves, upper and lower limb)
- Neuroimaging
- Formal hearing assessment
UMN tone?
Increased (spasticity or rigidity)
UMN inspection?
No fasciculation or significant wasting
UMN power?
Classically pyramidal pattern of weakness - extensors weaker than flexors in arms and vice versa
UMN reflexes?
Exaggerated or brisk
UMN plantar reflex?
Upgoing/extensor
LMN inspection?
wasting and fasciculation of muscles
LMN tone?
Decreased (hypotonia) or normal
LMN power?
Different depending on cause (eg. proximal weakness in muscle disease, distal in peripheral neuropathy)
LMN reflexes?
Reduced or absent
Spasticity - associated with?
Pyramidal tract lesions eg. stroke
Rigidity - associated with?
Extrapyramidal tract lesions (eg. Parkinson’s disease)
Spasiticy vs rigidity - velocity?
Spasticity is “velocity-dependent”, meaning the faster you move the limb, the worse it is
Rigidity is “velocity independent” meaning it feels the same if you move the limb rapidly or slowly.
Two types of rigidity?
- Cogwheel (Parkinson’s)
- Lead pipe (neurepileptic malignant syndrome)
Hip flexion - myotome?
L1/2
Hip flexion - muscle?
iliopsoas
Hip extension - muscle?
Gluteus maximus
Hip extension - nerve?
Inferior gluteal nerve
Knee flexion - myotome + nerve?
S1 + sciatic nerve
Knee flexion - muscle?
Hamstrings
Knee extension - myotome + nerve?
L3/4 + femoral nerve
Knee extension - muscle?
Quadriceps
Ankle dorsiflexion - myotome + nerve?
L4/5 - deep peroneal nerve
Ankle dorsiflexion - muscle?
Tibialis anterior
Ankle plantar flexion - myotome + nerve?
S1/2 - tibial nerve
Ankle plantar flexion - muscles?
- Gastrocnemius
- Soleus
Big toe - myotome + nerve?
L5 - deep peroneal nerve
Big toe - muscles?
Extensor hallucis longus
Knee jerk reflex?
L3/4
Ankle jerk reflex?
S1
Plantar reflex?
L5, S1
right touch assesses?
Dorsal columns and spinothalamic tracts
Pin prick assesses?
Spinothalamic tracts
Vibration assesses?
Dorsal columns
Proprioception assesses?
Dorsal columns
Further assessments and investigations after lower limb neurological exam?
- Full neurological examination (cranial, upper and lower)
- Neuroimaging
Shoulder aBduction - myotome + nerve?
C5 - axillary nerve
Shoulder Adduction - myotome + nerve?
C6/7 - thoracodorsal nerve
Shoulder aBduction - muscles?
Primarily deltoid
Shoulder adduction - muscles?
Trees major, lat dorsi, pec major
Elbow flexion - myotomes + nerve?
C5/6 (musculocutaneous and radial nerve)
Elbow flexion - muscles?
biceps brachii, coracobrachialis and brachialis
Elbow extension - myotomes + nerve?
C7 (radial nerve)
Elbow extension - muscles?
triceps brachii
Wrist extension - myotomes + nerve?
C6 (radial nerve)
Wrist extension - muscles?
extensors of the wrist
Wrist Flexion - myotomes + nerve?
C6/7 (median and ulnar nerve)
Finger extension - myotome + nerve?
C7 (radial nerve)
Wrist Flexion - muscles?
flexors of the wrist
Finger extension - muscles?
extensor digitorum
Finger flexion - muscles?
First dorsal interosseous (FDI)
Abductor digiti minimi (ADM)
Finger flexion - myotome + nerve?
T1 (ulnar nerve)
Thumb abduction - myotome + nerve?
T1 (median nerve)
Thumb abduction - muscles?
abductor pollicis brevis
Biceps reflex?
(C5/6)
Supinator reflex
C5/6
Triceps reflex
C7
General inspection of the patient - CN exam?
- Speech abnormalities
- Facial asymmetry
- Eyelid/ pupil abnormalities
- Strabismus
- limbs
Objects and equipment - CN exam?
- Walking aids
- Hearing aids
- Visual aids
- Prescriptions
CN I?
Olfactory
CN II?
Optic nerve
Inspection of the pupils?
- Assess pupil size
- Assess pupil shape
- Assess pupil symmetry
Things to do in eyes - CN exam?
- Inspect pupils
- Visual acuity
- Pupillary reflexes
- Colour vision
- Visual neglect
- Visual fields
- Blind spot - offer
- Fundoscopy
How to assess visual acuity?
Patient wearing normal glasses
1. Stand patient 6 metres from snellen chart
2. Ask patient to cover one eye and read the lowest line they are able to
3. You can have the patient read through a pinhole to see if this improves their vision - indicates a refractive component
4. repeat with other eye
Further steps for patients with poor vision?
- Reduce snellen to 3m
- Reduce to 1m
- Assess if they can count number of fingers
- Assess if they can see gross hand movements
- Assess if they can detect light
What can cause decreased visual acuity?
- Refractive errors
- Ambylopia
- Ocular media opacities such as cataract
- Retinal diseases eg. age-related macular degeneration
- Optic nerve pathology eg. optic neuritis
- Lesion sin higher pathways
How to assess the direct pupillary reflex?
- Shine light into patients eye and observe for restriction in same eye
- Normal is constriction of the pupil with light shone in
How to assess consensual pupillary reflex?
- Shine light into the same pupil but observe for constriction in the contralateral eye
- normal involves the contralateral pupil constricting due to light in the other eye
How to assess the swinging light test
Move torch between pupils - checks for relative afferent pupillary defect
How to assess accommodation reflex?
- Ask patient to look into distance
- Place finger approx 20-30cm in front of their eyes
- Ask patient to switch and observe pupils - they should constrict and converge bilaterally
Afferent limb of pupillary light reflex?
Sensory input is transmitted from retina, along optic nerve to ipsilateral pretetal nucleus
Two efferent limb functions - of pupillary light reflex?
- Motor output is transmitted from the pretectal nucleus to the Edinger-Westphal nuclei on both sides of the brain (ipsilateral and contralateral)
- Each Edinger-Westphal nucleus gives rise to efferent nerve fibres which travel in the oculomotor nerve to innervate the ciliary sphincter and enable pupillary constriction
Direct pupillary reflex - assess which limb?
The direct pupillary reflex assesses the ipsilateral afferent limb and the ipsilateral efferent limb of the pathway.
Consensual pupillary reflex - assess which limb?
contralateral efferent limb of the pathway.
Swinging light test - assess which limb?
used to detect relative afferent limb defects.
Relative afferent pupillary defect?
When the afferent limb in one of the optic nerves is damaged, partially or completely, both pupils will constrict less when light is shone int o the affected eye compared to the healthy one
Unilateral efferent defect?
- commonly caused by extrinsic compression of the oculomotor nerve
- ipsilateral pupil is dilated and non-responsive to light entering either eye (due to loss of ciliary sphincter function)
- consensual light reflex in the unaffected eye would still be present as the afferent pathway (i.e. optic nerve) of the affected eye and the efferent pathway (i.e. oculomotor nerve) of the unaffected eye remain intact
Causes of colour vision deficiencies?
- Optic neuritis
- Vit A deficiency
- Chronic solvent exposure
Visual neglect occurs when?
In the contest of parietal love injury after stroke
Scotoma?
an area of absent or reduced vision surrounded by areas of normal vision. There is a wide range of possible aetiologies including demyelinating disease (e.g. multiple sclerosis) and diabetic maculopathy.
What to do in oculomotor, trochlear and abducens nerves?
- Inspect eyelids
- Eye movements
CN III?
Oculomotor nerve
CN IV?
Trochlear nerve
CN VI?
Abducens nerve
Ptosis - associated with?
Oculomotor nerve pathology
Horner’s syndrome
Neuromuscular pathology (e.g. myasthenia gravis)
Oculomotor nerve palsy - presentation?
‘Down and out eye’
Due to unopposed lateral rectus and superior oblique
Trochlear nerve palsy - presentation?
Vertical diplopia - when looking inferiorly
Abducens nerve palsy - presentation?
Convergent squint
Lactreal rectus palsy
3 subdivisions of the trigeminal nerve?
- Opthalmic
- Maxillary
- Mandibular
CN V?
Trigeminal
3 elements to the trigeminal nerve assessment?
- sensory assessment
- Motor assessment
- Reflexes
Motor assessment of trigeminal nerve?
Muscles of mastication: temporals and masseter
Reflexes - trigeminal nerve?
- Jaw jerk reflex
- Corneal reflex
CN VII?
Facial nerve
Faical nerve - components of exam?
- Sensory
- Motor
sensory assessment of facial nerve?
Recent changes in taste?
Motor assessment of facial nerve?
- Hearing changes
- Inspection
- Facial movement
LMN facial nerve palsy?
All ipsilateral muscles of facial expression
Most common cause: bells palsy
UMN facial nerve palsy?
unilateral facial muscle weakness, however, the upper facial muscles are partially spared because of bilateral cortical representation (resulting in forehead/frontalis function being somewhat maintained)
The most common cause of upper motor neuron facial palsy is stroke.
Rinne’s test - how?
Place a 512 Hz tuning fork on the mastoid process and ask the patient to tell you when they can no longer hear it
Then move the fork in front of the external auditory meatus
Webers test - how
Place 512 Hz in midline of the forehead and ask where they hear the sound
Turning test?
Ask patient to march on the spot with arms outstretched and eyes closed
Glossopharangeal and vagus nerves - how to assess?
- ask if any issues with swallowing, voice or cough
- Ask patient to say ahh and cough
- Swallow assessment
- Gag reflex
Hypoglossal nerve - assessment?
- open mouth and inspect tongue for wasting + fasiculations
- Protrude tongue - observe for deviation
- Push tongue through cheek
Further assessments and investigations after CN exam?
- Full neurological exam
- Nueroimaging
- Formal hearing assessment + pure tone audiometry (If vestibulocochelear concern)
Inspection - Chracot Marie tooth?
- Guttering of dorsal interossei
- Claw hands
- Inverted champagne bottle appearance
- Pes cavus
- Fascilations - especially of distal muscles
- Food drop
- Walking aids
Tone in Charcot marie tooth?
Flaccid
Reflexes in Charcot marie tooth?
Typically absent or greatly diminished
Confirm absent with jendrassik manoeuvre
Power in Charcot marie tooth?
- Symmetrically affected
- Distall weakness usually predominates
- Plantarflexion relatively spared compared to dorsiflexion
- Proximal weakness typically only in severe
Coordination in Charcot marie tooth?
Normally preserved, only. impaired by weakness
Sensation in Charcot marie tooht?
May be spared till later on
- Sensory loss to pinprick and proprioception (glove and stocking)
- Demonstrate length dependant loss by running sharp object up the limb
Gait in Charcot marie tooth?
- High steppage
- May have sensory ataxia
Rhomberg - Charcot marie tooth ?
Positive Rhomberg’s sign as disease progresses
Differenital diagnosis in Charcot marie tooth presentation?
- Diabetic neuropathy
- Drugs (isoniazid, vincristine, amiodarone)
- Toxins (lead, alcohol)
- Metabolic (B12)
- Guillian barre
- HIV/Lyme
Investigations into a Charcot marie tooth presentation?
- Nerve conduction studies - to look for slowing velocity
- Consider genetic testing
- Fasting plasma glucose, Hba1c, B12, folate
- Detailed drug history
- Consider HIV, boreiella serology
Management of Charcot marie tooth?
- MDT approach
- Patient education
- Pysio + OT
- Analgesia for pain
- Orhtotics/ walking aids
Differential diagnosis for RAPD?
- OPtic neuritis (MS)
- other optic neuropathies (glaucoma, giant cell arteritis)
- Orbital disease (thyroid eye disease, orbital cellulitis)
- Infection (Lyme, herpes, syphylis)
Name the visual field defects?
- Total right eye visual loss
- Bitemporal hemianopia
- Left nasal hemianopia
- Right homonymous hemianopia
- Left homonymous hemianopia with macular sparing
Superior quadrantinopia - where lesion?
Temporal lobe
Inferior quadrantinopa - where lesion?
Parietal lobe
Homonymous hemianopia with macula sparing - where lesion?
Occipital lobe
Complete oculomotor palsy - presents with?
- Complete ptosis
- Dilated pupil (unopposed sympathetic action)
- Down and out eye
Isolated surgical third nerve palsy?
- Ipsilateral pupil dilation (parasympathetic fibres more superficial and susceptible to compression)
- Eye movements relatively spared
Medical third nerve palsy?
Due to microvascular infarction within the nerve fibres
Tend to cause pupil sparing lesions
Sixth nerve palsy?
Abducens nerve palsy = pure horizontal diplopia , paralysis go lateral gaze on affected side
Horners syndrome?
- Partial ptosis
- Miosis (pupil construction)
- Anhidrosis
Causes of Horners syndrome?
Various causes according to where the nerve is impaced
- 1st order: Pituitary tumour, high cervical myelopathy
- 2nd order: pancoats tumour, subclavian artery dissection, cervical rib
- 3rd order: Internal carotid artery dissection