Transcript Neurological Exam

The Neurological
Examination
Robin Meek, M.D.
Introduction to the Medical Profession
March 22, 2006
Objectives:
1. List and discuss the 3 essential questions
to consider when assessing neurological
function.
2. Describe the 6 components of the
neurological exam.
Three Key Questions
1.
Is there evidence of nervous system
disease or dysfunction?
2.
Where is the problem located?
3.
What is the nature of the problem?
1. Is there evidence of nervous
system disease or dysfunction ?

Focal – stroke

Diffuse – multiple sclerosis

Systemic –peripheral neuropathy
2. Where is the problem?

CNS vs. PNS

Tracts vs. neurons

UMN vs. LMN

Cortical vs. subcortical
Peripheral vs. Central

Peripheral
- Muscle
- Neuromuscular junction
- Spinal or cranial nerves
- Plexus
- Nerve roots

CNS
-
-
Spinal cord
Brainstem
Cerebellum
Cerebrum
-
Right vs. left
Cortex vs. subcortical
3. What is the nature of the
problem?
PIT VET 3-D
PIT VET 3 - D
PIT
- pressure
- infection
- toxic or metabolic
VET
- vascular
- epilepsy
- trauma
3-D
- demyelinating
- degenerative
- developmental
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6. Coordination
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
Mental Status

Alertness or awareness

Orientation
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
The Cranial Nerves
I
II
III
IV
V
VI
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
VII
VIII
IX
X
XI
XII
Facial
Acoustic
Glossopharyngeal
Vagus
Spinal accessory
Hypoglossal
Olfaction (CN I)
Almost never tested
 Smell
 Coffee, mint, essence of orange
 Impaired olfaction:

Inflammation (allergies or colds)
 Smoking
 Aging


Anosmia
CN II - Vision

Three steps:
1.Visual fields by confrontation
2. Visual acuity testing – patient should wear
their usual corrective lenses
3. Funduscopic examination –red reflex, optic
disc, retinal vessels
Pupillary Light Reflex (CN II,III)
Check pupil symmetry
 Swinging penlight– pupils should remain
equally constricted
 Anisocoria – one pupil is larger than the
other

- Normal variant
- Sympathetic vs. parasympathetic

Sympathetic – responsible for dilation
- asymmetry greatest in the dark

Parasympathetic – responsible for
constriction
- asymmetry greatest in the light
IV Trochlear

Downward and inward movement of the
eye

Innervates the superior oblique
VI Abducens

Lateral deviation of the eye

Innervates the lateral rectus
Nystagmus
Experiment on your buddy!
V Trigeminal

Mixed nerve – somatic sensory and
somatic motor

Sensory nucleus – pons and medulla,
becoming continuous with the posterior
horn of the spinal cord

Motor nucleus – confined to the pons
Trigeminal - Sensory

Three branches: opthalmic, maxillary,
mandibular

Sensory input from the face and mucus
membranes (ocular, nasal, and oral)
excluding the external ear and the
posterior head, via the trigeminal ganglion
Trigeminal - Motor

Supplies the muscles of mastication
(masseter, temporal, internal and external
pterygoid) muscles and other minor
pharyngeal muscles
Trigeminal Examination
1.
2.
3.
4.
Pinprick and fine touch sensation in
forehead, cheek, and mandible bilaterally
Corneal reflex
Jaw movements and jaw reflex
Palpation of jaw muscles for tone and
strength with teeth clenched
VII Facial

Mixed nerve

Motor – facial musculature except for
levator palpebrae (CN III)

Superior salivatory nucleus –
submandibular and sublingual glands
VII Facial Sensory

Nucleus solitarius – taste from anterior 2/3
of the tongue ( sweet and salty)

Sensory nucleus 5 – sensation from the
external ear
VII – Three Steps
1.
Inspection at rest and with facial
expression
2.
Wrinkling the forehead – differentiates
central from peripheral lesion
3.
Identifying sweet and salty tastes on both
sides of the tongue
Try it out!
VIII Acoustic

Hearing - cochlear division

Balance – vestibular division
- seldom tested in basic neuro. exam
VIII – Two Steps
1.
2.
Assess hearing, covering opposite ear:
whispered words
rubbing your fingers
ticking watch
Rinne test – bone and air conduction
IX Glossopharyngeal

Mixed nerve

Motor – pharynx

Sensory – posterior portions of the
eardrum and ear canal, the pharynx, and
the posterior tongue (salty, sweet, sour,
and bitter)
X Vagus



Mixed
Motor – palate, pharynx, and larynx
Sensory – pharynx and larynx
Testing IX and X

Listen to the patient’s voice – is it hoarse
or does it have a nasal quality?

Say “ah” – look at the soft palate and the
pharynx.

Gag reflex – stimulate both sides of the
back of the throat and note the gag
response (warn the patient)
XI Spinal accessory

Shoulder and neck movements
Look for atrophy or fasiculations in the
trapezius muscles, compare one side to
the other
 Shrug shoulders


Turn head against your hand
XII Hypoglossal

Somatic motor – muscles of the tongue

Observe the tongue for muscle atrophy or
fasiculations

Ask patient to protrude tongue and move it
from side to side – ? symmetry, deviation
from the midline
Your turn!
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
Motor Exam
Body position – abnormal positions alert
you to deficits such as paralysis
 Involuntary movements – tremors, tics, or
fasiculations
 Muscle bulk – atrophic, symmetric or
asymmetric? Especially shoulders, hands,
thighs
 Tone and strength

Muscle Strength
Grade 5 - full strength
Grade 4 - weak against resistance
Grade 3 - movement against gravity
Grade 2 – movement with gravity
eliminated
Grade 1 – minimal contraction
Grade 0 – no contraction
Muscle Tone
flaccid – a decrease in tone
normal – slight resistance to passive
movement
spastic – increased tone that varies,
often worse at the extremes of the
range
rigid – resistance that persists throughout
the range of motion and in both
directions
Lower Motor Neurons


Corticospinal tract or pyramidal system –
- mediates voluntary movements
- crosses over at the junction of the
brainstem and the spinal cord
Reticulospinal or rubrospinal tracts –
- extrapyramidal system
- connects basal ganglia with the LMN
- integrate motor activity and posture
UMN vs. LMN
UMN
LMN
Paralysis
spastic
flaccid
Muscle atrophy
no
yes
Fasiculations
no
yes
Reflexes
Hyper-reflexic
Hypo-reflexic
Babinski sign
May be present
Not present
Lower extremity nerve roots
Demonstration

Symmetric weakness of the proximal
muscles – myopathy or a muscle disorder

Symmetric weakness of the distal muscles
suggests a polyneuropathy or a disorder of
the peripheral nerves
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
Sensory Examination
1.
2.
3.
4.
5.
6.
Superficial pain and touch
Temperature
Deep pain or pressure
Vibration
Position
Discriminative functions
Ascending Tracts
Lateral spinothalamic – superficial pain
and temperature
 Posterior columns – vibration, deep
pressure, position sense, point location,
stereognosis, and two-point discrimination
 Spinocerebellar – proprioception
 Ventral spinothalamic – superficial touch
and deep pressure


Superficial pain – pinprick , “sharp or dull”

Light touch – fingertips or wisp of cotton

(Temperature – ice and warm water in test
tubes)
Deep pain – squeezing the calf or biceps
muscle
 Vibration sense – vibrating tuning fork
against bony prominences with patient’s
eyes closed, “When does it stop?”
 Position sense – holding a distal joint of
the fingers and toes and moving up or
down

Discriminative Function

Reflects the ability of the sensory cortex to
correlate, analyze, and interpret
sensations

Sterognosis – identify an object (coin)

Two-point discrimination - find the distance
where the patient no longer perceives two
stimuli
Graphesthesia – recognize numbers or
letters drawn on skin
 Extinction – touch both sides of the body
simultaneously with closed eyes
 Point location – with the patient’s eyes
closed, touch an area on the body,
withdraw the stimulus, and then ask the
patient to point to the area touched

Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
Reflexes

Superficial reflexes:
- abdominal reflex – contraction toward the
stimulus
- cremasteric reflex – elevation of the
ipsilateral scrotum and testicle by touching
the thigh
Deep Tendon Reflexes
0 Absent
1+ Hyporeflexic
2+ Normal
3+ Hyperreflexic
4+ Clonus
Eliciting Reflexes
1.
2.
3.
4.
5.
6.
7.
Biceps (C5, C6)
Brachioradialis (C5, C6)
Triceps (C6, C7)
Patellar (L2, L3, L4)
Achilles (ankle – S1)
Plantar (L5, S1)
Clonus – indicates CNS disease
Demonstration
Babinski sign
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination
Coordination

Four areas that need to work together:
1. Motor system
2. Cerebellum – for rhythmic movement
and steady posture
3. Vestibular system – for balance & for
coordinating eye, head, and body
movements
4.Sensory system – for position sense
Coordination

Rapid alternating movements

Point to point movements

Gait – walk down the hall, heel to toe, walk
on toes, and then on heels

Standing – Romberg test
Pronator Drift
Changes With Aging
Motor system – move and react with less
speed and agility, muscle mass decreases
 Benign essential tremor
 Vibration sense decreased or lost in feet
or ankles
 Reflexes – gag, ankle reflexes decreased
 “Benign forgetfulness”

Demo
Six Components
1. Mental status
2. Cranial nerves
3. Motor
4. Sensory
5. Reflexes
6.Coordination