Neurological Examination Flashcards
What are the three main components of the approach to neurological diagnosis?
- History
- Examination
- Investigations
What are the two main questions to consider when making a neurological diagnosis?
- Where is the lesion?
- What is the lesion?
What is the primary purpose of examining patients?
To localise pathology within the nervous system
For what other reasons might we examine patients?
▪️Evaluate function
▪️Monitor change
▪️Identify avenues for treatment
▪️Promote patient understanding
▪️Helpful if complaint is made
▪️Ritual
What is a myelopathy?
Abnormality/disease of the spinal cord
What is a radiculopathy?
Abnormality/disease of the nerve roots (leaving spinal cord in PNS)
Multiple = polyradiculopathy
What is plexopathy?
Abnormality/disease of the plexus
(bundles of nerves, either brachial or lumbar)
What is myopathy?
Abnormality/disease of the muscles
Examination should be….
Tailored to the clinical scenario
What are the three main elements of a standard neurological examination?
- Higher mental function
- Cranial nerves
- Motor and sensory examination of the limbs (including gait)
How many pairs of cranial nerves do we have?
12
What is the first cranial nerve (I)?
Olfactory nerve
When might be test the olfactory nerve and how?
▪️Rarely formally tested
▪️Might be relevant post-head injury or in patients with suspected PD as could be prodromal
▪️Formal test = UPSIT
What is the second cranial nerve (II)?
Optic nerve
How is visual acuity measured and what is the normal result?
▪️Snellen chart (opticians)
▪️6/6 - row 6 from 6 metres away
What elements of optic nerve function can we measure?
▪️Visual acuity
▪️Visual fields
▪️Pupillary reflexes (light, accommodation)
▪️Colour vision
▪️Fundoscopy - examination of fundus/retina
What is accommodation?
Pupils restrict when focuses on something close up
What is a healthy pupillary reflect to light?
They constrict
What can you infer about the location of a lesion if someone has complete loss of vision is one whole field (e.g. right)?
The problem is either in the eyes itself or early on in the optic nerve
(just behind the eye, after the optic chiasm)
What are the two main signs to look for when conducting a fundoscooy to look at the optic disk?
▪️Papilloedema (swelling of optic nerve head)
▪️Optic atrophy
What conditions might you see optic atrophy in?
Multiple sclerosis - optic nerve looks whiter and brighter where previously inflamed
What might papilloedema suggest?
Raised intracranial pressure
What are cranial nerves III, IV, and VI important for?
Eye movement
What two eye movements do you check for during exam?
▪️Pursuit movements (following finger)
▪️Saccadic movements (moving quickly to meet a target)
What is the fifth cranial nerve (V)?
Trigeminal nerve
What does the trigeminal nerve do?
▪️Sensation to the face
▪️Motor supply to muscles of mastication (chewing)
How do we examine the trigeminal nerve?
▪️Feel cotton wool or pinprick
▪️Strength and feel or muscles
▪️Corneal reflex
▪️Jaw jerk
What are the three branches of the trigeminal nerve?
▪️V1 - opthalamic
▪️V2 - maxillary
▪️V3 - mandibular
What is the seventh cranial nerve (VII)?
Facial nerve
What does the facial nerve do?
▪️Control muscles of facial expression
▪️Taste to front 2/3 of tongue
Where might damage be in the facial nerve pathway if someone has weakness in the whole of one side of the face?
The lower motor neuron
Where mignt damage be in the facial nerve pathway if someone has weakness at the bottom of one side of the face, but the top part is spared?
The upper motor neuron
(Top of the face receives bilateral supply which can protect it from damage)
What is the eighth cranial nerve?
Vestibulocochlear
What does the vestibulocochlear nerve control?
Hearing and balance
How can we examine the vestibulocochlear nerve?
▪️Screen hearing
▪️Vestibular function - assessment of gait and nystagmus
What can a tuning fork be used for?
Distinguishing sensorineural deafness from conductive deafness
What might nystagmus suggest?
▪️Vestibular problems (VIII cranial nerve)
▪️Cerebellar problems
What is the ninth cranial nerve (IX)?
Glossopharyngeal nerve
What is the tenth cranial nerve (X)?
Vagus nerve
What problems might arise from IX and X cranial nerve dysfunction?
Dysarthria and dysphagia
(speech articulation and swallowing)
How can we test the IX and X cranial nerves?
▪️Say ‘aaah’ and look for palatal elevation
▪️Check gag reflex
▪️Check speech and swallowing
▪️Cough
What does the glossopharyngeal nerve control?
▪️Taste to back 1/3 of tongue
▪️Pharyngeal sensation
▪️Gag reflex
What does the vagus nerve control?
▪️Gag reflex
▪️Vocal cords
What is the eleventh cranial nerve (XI) ?
Accessory nerve
What does the accessory nerve control?
▪️Upper part of trapezius muscles
▪️Sternocleidomastoid muscles
What is the twelth cranial nerve (XII)?
Hypoglossal nerve
What does the hypoglossal nerve control?
Motor supply to the tongue
How can you use tongue protrusion testing to determine location of a hypoglossal nevre lesion?
Tongue will often deviate to the side of the problem
How can you examine hypoglossal nerve function?
▪️Observe tongue for wasting and fasciculation
▪️Tongue protrusion
▪️Power and speed of movement
What might you see with damage to the left optic radiation?
Right hemianopia
When might you see loss of a quadrant of visual field?
If optic radiation is lost within the parietal or temporal lobes
What are the two main parts of limb examination?
- Motor
- Sensoryv
What are the main elements of examining limb motor function?
▪️Observations
▪️Tone and clonus
▪️Power
▪️Reflexes
▪️Coordination
▪️Gait
Where does the upper motor neuron originate and where does it cross over?
▪️From motor cortex
▪️Crossed over in pyramids of the medulla (pyramidal/corticospinal tract)
Where does the spinal cord terminate?
At the L1 vertebra with the conus medullaris and L1 pedicle
What is below the conus medullaris?
▪️Cauda equina
▪️Lower motor neurons
How would pathology below the L1 vertebra/conus present?
As lower motor neuron signs
How many pairs of nerve roots do we have?
31
What is a myotome?
The spinal root supply of a muscle
(e.g. biceps are supplied by C5/6)
What is a dermatome?
The region of skin supplied by a particular spinal root
What is a plexus and what are the two main types?
▪️Structure where nerve roots come together, reorder, and project down to the limbs
, ▪️Brachial
▪️Lumbosacral
What signs can you look for during observation in the motor examination?
▪️Wasting - loss of muscle bulk
▪️Fasciculation - twitches
▪️Abnormal movements (hypokinetic/Hyperkinetic)
What might muscle wasting and fasciculation be a sign of?
Lower motor neuron pathology
What are fasciculations?
Twitchy movements due to spontaneous contractions as the muscle loses its nerve supply
What is tone?
The resistance to passive movement
What are the two main types of increased muscle tone?
▪️Spasticity
▪️Rigidity
How might spasticity present and what pathology does it suggest?
▪️Velocity dependent - worse when move limb quickly
▪️”Clasp-knife” - lots of resistance when try to extend which quickly gives way
▪️Sign of UMN lesion
How might spasticity present and what pathology does it suggest?
▪️”Lead pipe” - same throughout whole range of movement
▪️Not velocity dependent - same however fast you move it
▪️Basal ganglia pathology
What is ankle clonus?
▪️Multiple repetitive contractions (>2/3) in calf in response to flex of foot
▪️Often UMN sign alongside spasticity
What do you use to grade motor power?
MRC grading (0-5)
What are the most common patterns of weakness?
▪️Proximal
▪️Distal
▪️Pyramidal
▪️Focal
What might a proximal pattern of weakness suggest?
Muscle disease
(muscles near the trunk)
What might a distal pattern of weakness suggest?
Nerve disease
(hands and feet)
What is a pyramidal pattern of weakness and what might it suggest?
Upper motor neuron pathology
More weakness of extensors in arms and flexors in legs
What might a focal pattern of weakness suggest?
Damage to a single nerve root or peripheral nerve
What happens when you strike a tendon?
▪️Sensory impulse sent to spinal cord
▪️Signal returns via LMN to muscle
▪️Kept in check by UMN
How do muscles generate tone?
Constant activity of the reflex loop
(LMN and reflect arc stimulate each other)
What is the role of the UMN in the reflex loop?
Inhibitory control
What does a loss of reflex tell us about pathology?
LMN problem
How might an UMN problem affect reflexes?
▪️Loss of inhibitory control of loop
▪️Exaggerated reflex
(explains spasticity in UMN lesions)
What might loss of a single reflex suggest?
Problem with a specific nerve root
What is the plantar response (babinski sign)?
Scratch bottom of foot and observe big toe
Normal = flexor response (toe goes down
Abnormal (UMN) = extensor response (toes fan up)
Where might upper motor neuron damage occur?
▪️Brain
▪️Brainstem
▪️Spinal cord
Where might lower motor neuron damage occur?
▪️Nerve root (anterior horn of spinal cord)
▪️Plexus
▪️Nerve
What might you see on observation indicating UMN damage?
Contracture (limb pulled into weird position)
What might you see on observation indicating LMN damage?
Wasting and fasciculation
What is the difference between tone and power?
Tone = resistence to PASSIVE movement
Power = resistance to ACTIVE movement
What are the main signs of UMN damage?
▪️Increased tone (spasticity)
▪️Decreased power
▪️Brisk reflexes
▪️Extensor plantar response
What are the main signs of LMN damage?
▪️Decreased tone (flaccid)
▪️Decreased power
▪️Absent reflexes
What are the main elements of examining limb sensory function?
▪️Observe
▪️Delineate boundaries of any sensory loss
▪️Light touch
▪️Pinprick
▪️Vibration
▪️Proprioception
How can you test coordination and functioning of the cerebellar?
▪️Nystagmus and slurred speech (cranial nerve exam)
▪️Finger-nose test
▪️Rapid alternating movements (e.g. tap front and back of hand) (dysdiadochokinesis)
▪️Heel-shin test
▪️Gait
What are the two signs of cerebellar dysfunction you might see with the finger-nose test?
▪️Dysmetria (missing target)
▪️Intention tremor (increases as approaches target)
what gait disturbances might be observed in someone with cerebellar disease?
▪️Broad based gait
▪️Ataxia
▪️Fall to side of lesion
What patterns of sensory loss might you see with radiculopathy?
Dematomal pattern - sensory loss to areas served by those nerve roots
What patterns of sensory loss might you see with polyneuropathy and why?
Glove and stocking patterns
Usually longer nerves are first affected
What patterns of sensory loss might you see with mononeuropathy?
Loss to area supplied by that nerve
E.g. median loss with carpal tunnel syndrome, common peroneal
What are the main limitations of neurological examination?
▪️Hard to judge what is normal and abnormal (large range)
▪️May be affected by other factors (e.g. age, anxiety)
▪️”Hard” vs “soft” signs
▪️Bias
▪️Inter-rater reliability (subjective element)
When is neurological examination most relevant in neuropsychiatry?
▪️FND - diagnosis and treatment
▪️Movement disorders (e.g. PD)
▪️Dementia (e.g. DLB vs AD)
▪️Acute/subacute cognitive and behavioural symptoms
