Neuro Flashcards
Lesion to CN iiii
Diplopia when looks down and away from affected side
Usual causes of CN vi lesions
Trauma , wernikes encephalopathy
Features of CN vi lesions
Failure of lateral movement
LMN lesion of facial
Usual cause
Ipsilateral weakness of muscles of facial expression
Bell’s palsy
UMN of facial
Usual cause
Insulate real weakness of muscles of facial expression but SPARES FOREHEAD
Tumours / vascular events
Facial nerve involvement in hearing?
Damage ->
Motor supply to stapedius
Hyperacusis (loud distortion of sounds)
Hip flexion nerve
L1,2
Knee flexion / hip extension nerve
L5 s1,2
Knee extension nerve
L2,3,4
Knee jerk nerve
L3,4
Ankle jerk nerve
S1,2
Plantar reflex nerve
L5 s1,2
Dermatomes of legs
Upper thigh l2 Anterior knee l3 Inner calf l4 Outer calf l5 Lateral foot s1
Heel to toe walking tests for
Midline cerebellar lesion
Difficulty walking on toes
S1 lesion
Difficulty walking on heels ? (Foot drop )
L4/5 lesion
Parkinson’s gait
Hesitation in starting Shuffling Freezing Diminished swinging of arms Propulsion
Cerebellar ataxia gait
Broad based
Unstable
Tremulous
Sensory ataxia gait
Broad based and high stepping
Distal vs proximal weakness gait
Distal - affected leg raised high and foot slaps ground
Proximal - waddling
Never supply: Deltoid Pec major / lats Biceps Triceps Wrist flexion Wrist extension Finger flexion Finger extension. Dorsal interrossi (splay fingers) Palmar interrossi
Deltoid c5,6 Pec major / lats c6,7,8 Biceps c5,6 Triceps c7 Wrist flexion c6,7,8 Wrist extension Finger flexion Finger extension. Dorsal interrossi (splay fingers) Palmar interrossi
Lesion of CN III
Eye pointing down and out with a fixed dilated pupil
Pstosis
Never supply: Deltoid Pec major / lats Biceps Triceps Wrist flexion Wrist extension Finger flexion Finger extension. Dorsal interrossi (splay fingers) Palmar interrossi
Deltoid c5,6 Pec major / lats c6,7,8 Biceps c5,6 Triceps c7 Wrist flexion c 6,7,8 Wrist extension c7,8 Finger flexion c7,8 Finger extension. C7,8 Dorsal interrossi (splay fingers) c8,t1 Palmar interrossi c8, t1
Nerves for
Biceps reflex
Triceps
Supinator
Biceps c5,6
Triceps c7,8
Supinator c5,6
Dermatomes of arm
Lateral upper arm - c5 Lateral forearm and thumb - c6 Middle finger - c7 Little finger - c8 Medial upper arm - t1
Cerebellar signs
DANISH Disdiadokinesis Ataxia Nystagmus Intension tremor Slurred speech Hypotonia
Cerebellar function tests
Heel to shin
Finger to nose
Finger to nose to finger
Rapid alternating movements
Basic causes of cranial nerve lesions
Trauma, diabetes, tumours, MS
Used for visual acuity
Snellen chart
Why are muscles of forehead sometimes spared from UMN lesions
They have bilateral UMN supply
What does a bovine (non explosive cough suggest)
Vagal palsy
Key parts of Cerebellar exam
DANISH Disdiadokinesis Ataxia (gait and posture) Nystagmus Intention tremor Slurred, sticato speech Hypotonia / heel shin test
What does innatention suggest
Damage to frontal / parietal lobes (stroke/trauma etc)
Lack of consensual pupillary response could indicate ?
Damage to one or both optic nerves
Damage to edinger westphal nucleus
Swinging light test can detect?
What does it look like?
Caused by?
Eg?
Relative afferent pupillary defect (RAPD) (marcus-gunn pupil)
Dilation of the affected pupil when light shines into it (should constrict)
Damage to tract between optic nerve and chiasm
Eg optic neuritis in MS
What is a squint called
Strabismus
What is a saccade
Rapid jerky movement that corrects the gaze after a slower deviation
What is the red reflex?
Absent means?
Light reflecting back from the retina (30cm away)
Cataracts
In unilateral Cerebellar disease which way is the deviation?
Why?
Towards the side of lesion due to hypotonia
Why do you use the heel to toe walking for Cerebellar disease?
What does it assess?
Exaggerates any unsteadiness
Assesses function of Cerebellar vermis
What is the first function to be lost in alcoholic Cerebellar cortical degeneration
Heel to toe walking
In a Cerebellar exam what would a positive rombergs test indicate
Unsteadiness is due to sensory ataxia (damage to dorsal columns of spinal cord) rather then Cerebellar ataxia
What would a slow upward pronator drift indicate
Lesion in the contralateral cerbellum
What does a positive rebound phenomenon suggest
Cerebellar disease
What is a pendular reflex mean ?
When do you get it?
Leg keeps swinging after you elict the knee reflex
Cerebellar disease
Reflexes in Cerebellar disease
Mild hypo reflexes
What is an intention tremor
Gets worse at endpoint of a deliberate movement
Failure of Disdiadokinesis suggests
Cerebellar ataxia
Things to look for in lower limb inspection
SWIFT Scars Wasting Involuntary movements Fasiculations Tremor
Possible causes for abnormal heel to toe gait
Weakness
Impaired proprioception
Cerebellar disorder
What does heel walking test
Dorsiflexion power
Positive rombergs test suggests
Sensory ataxia (defective proprioception / vestibular system)
Hip nerve roots Flexion Extension Abduction Addiction
Flexion L1/2
Extension L5/s1
Abduction L4/5
Adduction L2/3
Knee nerve roots
Flexion
Extension
Flexion - S1
Extension - L3/4
Big toe extension nerve root
L5
Reflexes
Knee jerk
Ankle jerk
Plantar response
Knee jerk L3/4
Ankle jerk l5/s1
Plantar response S1
What is an abnormal plantar response ?
Indicative of?
Babinski sign (extension of great toe) UMN lesion
What tract is light touch
Dorsal / posterior columns
Pin prick sensation
Spinothalamic
Vibration sensation tract
Dorsal / posterior columns
Proprioception tract
Dorsal / posterior column
Inability of heel to shin test indicated
Loss of motor strength / proprioception
Cerebellar disorder
Pronator drift indicates
UMN pathology
Rigidity when assessing tone suggests
Parkinson’s
Shoulders
Abduction
Adduction
Ab - C5
Ad- C6/7
Elbow
Flexion
Extension
Flex - C5/6
Extension - C7
Wrist
Extension
Flexion
Extension - C6
Flex - C6/7
Finger
Extension
Abduction
C7
T1
Muscles for abduction of fingers
First dorsal interosseous
Abductor digiti minimi
Thumb abduction
C8/t1
Reflexes
Biceps
Triceps
Supinator
B- c5/6
T - c7
Sup - C6
Nose to finger test may indicate
Cerebellar pathology
Failure of Disdiadokinesis
Cerebellar ataxia
Axillary nerve Root Muscle Action Sensation
C5
Deltoid
Shoulder abduction
Regimental badge over deltoid
Musculocutaneous Root Muscle Action Sensation Reflex
C5/6 Biceps Elbow Flexion Lateral aspect of forearm Biceps
Radial Root Muscle Action Sensation Reflex
C7 Extensiors Wrist / finger extension Anatomical snuff box Triceps
Ulnar Root Muscle Action Sensation
T1
First dorsal interosseous
Index finger abduction
Medial side of palmar hand and medial border of ring finger
Median nerve Root Muscle Action Sensation
T1
Abductor pollicis brevis
Thumb abduction
Lateral side of hand palmar
What is strabismus
Eyes don’t quite point the same way
How is visual acuity measured
How far should the snellen chart be held away
Chart distance (m) / lowest line read 6m (can be reduced to 3 then 1 if top line can't be read)
How do you test colour Vision
Ishihara charts
How do you do fundoscopy
Dilate pupils with shirt acting mydriatic eye drops
Darken room
Ask patient to fixate on distant object
Assess for red reflex - look through ophthalmoscope and observe for reddish reflection of pupil
When might the red reflex be absent
Cataract
Rarely - neuroblastoma
What else is examined in fundoscopy
Begin medialy and assess optic disk (colour, contour, cupping)
Assess retinal vessels ( cotton wool spots, neovascularisation)
Assess macula (ask to look directly into light - drusen noted in degeneration (yellow deposits made of lipid))
Ptosis indicates
Oculomotor nerve pathology
Cover test responses
No movement - normal
Eye moves temporally - convergent squint
Eye moves nasally - divergent squint
Facial light touch sensation
Branches
Forehead - opthalmic v1
Cheek - maxillary - v2
Jaw - mandibular v3
Complete closure of jaw when testing jaw jerk indicates
UMN lesion
Normal corneal reflex
Direct and consensual blinking
When assessing facial why do you look at external auditory meatus
Herpes zoster lesions (Bell’s palsy)
Facial nerve supply
Muscles of face
Stapedius
Taste to anterior 2/3 of tongue
What is normal result in Rinnes test
Neural deafness
Conductive deafness
Air conduction > bone conduction
Air > bone (both reduced equally)
Bone > air
Webers test
Normal
Neural deafness
Conductive deafness
Sound heard equally
Neural - sound heard louder on intact ear
Conductive - sound heard louder on side of affected ear
How to test vestibular
Ask patient to march on spot with eyes closed
Vestibular lesion - patient will turn to that side