View
4
Download
0
Category
Preview:
Citation preview
Randa M. Albusoul
Neurological Assessment
Anatomy
The nervous system can be divided into:
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
# CNS includes brain and spinal cord
#PNS includes 12 pairs of Cranial Nerves (CN) and
31 pairs of spinal nerves.
The brain consists of:
•Cerebrum: vast network f interconnecting neurons.
Nerve cell = cell body and axon.
Brain tissue may be gray or white matter.
Gray matter (neuronal cell bodies)
White matter: (neuronal axons).
•Why cerebral cortex is gray?
Because it lacks myelin
•Hemisphere: is a half of the cerebrum.
•Each hemisphere has 4 lobes.
•Each lobe mediate specific function.
•Frontal lobe:
personality, behavior,
emotions, and
intellectual function.
•Contains Broca’s area
that mediates motor
speech; when injured
lead to expressive
aphasia; person cannot
talk.
•Parietal lobe: primary center for sensation.
•Occipital lobe: primarily visual receptor center.
•Temporal lobe: primarily auditory reception center.
•It also contains Wernicke’s area for language
comprehension (receptive aphasia: hear sounds but
have no meaning for him).
•Basal Ganglia: movement. Example; Arm and leg
swinging during movement.
•Thalamus: processes sensory impulses and relays
them to the cerebral cortex.
•Hypothalamus: maintain homeostasis, regulates
temperature, heart rate, blood pressure, sleep
center, emotional behavior, pituitary gland
regulator.
•Cerebellum: voluntary movements, equilibrium,
and muscle tone.
•Brain Stem: midbrain, pons, medulla (has vital
autonomic centers: respiratory, heart, gastro).
Spinal Cord:
•Long structure that connect the
brain with the spinal nerves.
•It can mediates reflexes.
•Ends at 1st or 2nd lumber
vertebra.
Pathways of the
CNS:
Sensory pathways:
•There are sensory
receptors in skin,
mucosa, muscles,
tendons, and
viscera..
•The brain monitor
the organ sensation,
position, function…
•Sensation travels in the afferent fibers in the
peripheral nerve then posterior root then spinal cord.
•Then there are two methods to go to the brain:
Spinothalamic tract for sensation of pain, temp, and
touch; from the posterior root these sensations travel
in the second sensory neuron to the opposite side and
ascend up the spinothalamic tract to the thalamus there
fibers synapse with a third sensory neuron that carry
them to sensory cortex.
Posterior columns: these fibers conduct the sensation
of position, vibration, and localized touch.
•From the posterior root by the same side proceed at
the medulla synapse with the second neuron and then
cross, then thalamus then synapse and proceed to the
sensory cortex.
Sensation of position: proprioception; without looking
you know where your body parts are in space and in
relation to each other.
Sensation of vibration: feeling vibrating objects.
Localized touch: stereognosis; without looking you
can identify familiar objects by touch.
Note that LT cerebral cortex receives sensory info
from and controls motor function to the RT side of the
body and visa verse this is called crossed
representation.
Motor Pathways:
Pyramidal tract
(corticospinal):
•Motor cortex then brain
stem, then (a) cross to the
opposite side pass down in
the lateral column; (b)
anterior column of the
spinal cord.
•For voluntary skilled,
discrete, purposeful
movements such as writing.
Extrapyramidal tracts: include motor fibers that
originate in motor cortex, basal ganglia, brain stem,
and spinal cord; this is lower more primitive motor
system that maintain muscle tone and control body
movements such as walking.
The PNS:
The Cranial Nerves (CN): emerge from cranium;
CN I and II from the brain.
CN III to XII fro diencephalon and the brainstem.
The peripheral nerves:
•31 nerve; 8 cervical, 12 thoracic, 5 lumbar, 5 sacral,
1 coccygeal.
•Each nerve has an anterior root containing motor
fibers, and posterior root containing sensory fiber.
•The anterior and posterior roots merge together to
form spinal nerve.
Reflexes: involuntary mechanism that permit a quick
reaction to painful or damaging situation.
Types of reflexes:
• deep tendon reflex.
•Superficial reflexes: such as corneal reflex and
abdominal reflex.
•Visceral reflexes (organic): pupillary response to light
and accommodation.
•Pathologic (abnormal) reflexes: such as Babinski’s
reflex.
Reflex arc:
Sensory stimulus,
posterior root, spinal cord,
synapse with a motor
neuron in the anterior
horn, anterior root,
muscle.
Dermatomes:
•Band of skin that is innervated by the sensory root
of a single spinal nerve
•Help to localize the lesion to a specific spinal cord
segment.
Subjective Data
Common symptoms
Headache
Dizziness or vertigo
Weakness
Numbness or loss of sensation
Loss of consciousness
Seizure
Tremors
Difficult swallowing
Difficult speaking
Objective Data
1) Mental status and level of Consciousness.
Is the pt oriented to time, place, and person?
2) CN:
*Olfactory (I) (S): test sense of smell.
*Optic (II) (S): test visual acuity and fields (by
confrontation).
*Oculomotor (III), Trochlear (IV), Abducens (VI) (M):
Pupils size, reflex, accommodation, & upper lid
movement (III) & asses extra ocular movement.
*Trigeminal (V) (M/S):
•Assess the muscles, jaw
clenching for temporal and
masseter, lateral jaw movement
for lateral pterygoids.
•Assess all three devision of
the nerve (ophthalmic,
maxillary, and mandibular).
Compare between sharp and
dull or hot and cold sensations
in each side.
•Corneal reflex: make the pt look up and away
from you. Touch the cornea by cotton, the
normal reaction is blinking, the sensory of this
reflex is carried by CN (V), and the motor by
CN (VII).
*Facial (VII) (M/S):
•M / facial expression during movements; smile, close
eyes then open, frown, lift eyebrows, show teeth, puff
cheeks, close mouth.
•S / taste (sugar, salt, sour, bitter) on the anterior two
third of the tongue.
*Acoustic (VIII) (S): hearing acuity; whisper, Weber,
Rinne.
*Glossopharyngeal (IX) & Vagus (X) (M/S):
M / uvula (in midline) & soft
palate rise, positive gag reflex
(CN X),
S / taste on posterior 1/3 of the
tongue (salty, sweet, sour, bitter)
CN (IX).
*Spinal accessory (XI) (M): assess the muscles,
shoulder shrug (trapezius), turn head to each side
against your hand (sternomastoid).
*Hypoglossal (XII) (M):
Ask the pt to protrude the tongue, look for
symmetry/midline, ask pt to talk (CN V, VII, X, XII).
3) The motor system:
Coordination requires muscle strength, cerebellar
system, vestibular system, and sensory system
(position sense).
•Assess rapid alternating movement:
Ask the pt to strike one hand on the thigh,
raise the hand, turn it over, and then strike
the back of the hand down n the same place.
Point-to-point movements:
•Finger to nose; smooth & accurate movement; move
your finger, or fix it and make the pt close her eyes.
•Heel to shin: moves heel in a straight line down the
shin.
•Gait:
Assess pts walking across the room (posture,
balance, swinging of the arms..).
Walk heel-to-toe in a straight line.
Walk on the toes.
Hop in place.
Do a shadow knee bend.
Rise from a sitting position.
•Stance:
Romberg test:
ask the person to stand up with feet
together and arms at sides, close eyes.
Maintain posture & balance with slight
swaying.
Pronator drift:
4) The sensory system:
To evaluate the sensory system, test the
following:
●Pain and temperature (spinothalamic tracts)
●Position and vibration (posterior columns)
●Light touch (both spinothalamic and posterior)
●Discriminative sensations, which depend on
some of the above sensations but also involve the
cortex.
*compare symmetrical areas and proximal and
distal areas.
*vary the pace of your testing.
*Map out the boundaries.
•Pain: you can use broken tongue blade and cotton
swap.
•Show the pt both sensations before closing his eyes.
•Use lightest pressure needed.
•If pain assessment is normal no need for temperature
assessment.
•Light touch: see if the pt feel the touch and can
compare between sides.
•Vibration: if he can feel it and when it stops.
•Proprioception: up and down.
•Discriminative sensation:
•Stereognosis:
•Graphesthesia: number identification.
•Two point discrimination:
•Find minimal distance in
different body parts.
•Point localization.
•Extinction; simultaneously
stimulate corresponding
areas on both sides
of the body and ask where
the pt feel it.
5) Dermatomes:
Assess dermatomes of the pt, some landmarks may
be:
C3: Front of the neck
T4: Nipples
T10: Umbilicus
L1: Inguinal
6) Tendon reflexes:
•Encourage the pt to relax before beginning the
procedure.
•In documentation, follow the following grading
scale:
The knee reflex (Patellar Reflex) (L2, L3, L4):
•The pt may be sitting or lying but knee should be
flexed.
•Tap the patellar tendon below the paterlla.
•Note contraction of the quadriceps with extension
of the knee.
The Plantar response (L5,S1):
•Stroke the foot from the heel moving up toward the
small toe to the ball of the foot, curving medially
across the ball.
•The normal response is a downward contraction of
the toes, called the plantar response.
•The abnormal response is called Babinski response.
Plantar response Babinski response
Recommended