Download 09. Assessment of Neurologic System

Assessment of
Neurologic System
Anatomy and Physiology
Nervous system controls
body functions through
voluntary and autonomic
responses to external and
internal stimuli
Nervous system consists
of the central nervous
system (brain and spinal
cord), peripheral nervous
system and the
autonomic nervous
system
Anatomy and Physiology:
Central Nervous System

Protective structures
Skull protects the brain
Foramen magnum – spinal
cord extends from medulla
oblongata in brainstem
Meninges – between the
skull and the brain
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Dura mater, arachnoid and
pia mater
Subarachnoid, between
arachnoid and pia mater,
where cerebrospinal fluid
(CSF) circulates
• Cerebral ventricular system – four
interconnecting chambers (ventricles) that
produce and circulate CSF
One lateral in each hemisphere, 3rd adjacent to
thalamus, 4th adjacent to brainstem.
Cerebrospinal fluid and cerebral ventricular system
 CSF –colorless, odorless fluid that contains glucose,
electrolytes, oxygen, water, carbon dioxide, protein
and leukocytes
 Produced in choroid plexus of ventricles
 Circulates around brain and spinal cord to provide
cushion, maintain normal intracranial pressure,
provide nutrition and remove metabolic wastes
CSF circulation: from lateral ventricle through
interventricular foramen to 3rd ventricle through aqueduct
of Sylvius to 4th ventricle into cisterna magna (small
reservoir for CSF).
From cisterna magna, CSF flows up around brain and
down around spinal cord.
CSF absorbed through arachnoid villi and returned to
venous system
Anatomy and Physiology:
Brain
Consists of cerebrum, diencephalon, cerebellum
and brainstem
Gray matter (cell bodies) and white matter
(myelinated nerve fibers)
Anatomy and Physiology:
Brain (cont)

Cerebrum – Largest part of brain
Composed of two hemispheres divided into four lobes ( frontal lobe,
parietal lobe, temporal lobe, and occipital lobe)
Frontal lobe –primary motor cortex and responsible for voluntary
motor activity functions, controls intellectual function, awareness of
self, personality and autonomic responses related to emotion

Left frontal lobe – Broca’s area – formulation of words
Parietal lobe – contains primary somesthetic (sensory) cortex

Major function to receive sensory input such as position sense, touch,
shape and texture of objects
Temporal lobe –contains primary auditory cortex and interprets
auditory, visual and somatic sensory inputs that are stored in
thought and memory

Left temporal lobe – Wernicke’s area – responsible for comprehension
of spoken and written language
Occipital lobe – contains primary visual cortex and is responsible for
receiving and interpreting visual information
Anatomy and Physiology:
Brain (cont)
Diencephalon – comprises thalamus,
hypothalamus, epithalamus and subthalamus
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Thalamus – relay station
Hypothalamus – maintain homeostasis
Regulation of body temperature, hunger and thirst,
formation of autonomic nervous system responses
and storage and secretion of pituitary gland hormones

Basal ganglia - create smooth, coordinated
voluntary movement by balancing production of
two neurotransmitters: acetylcholine and
dopamine
Anatomy and Physiology:
Brain (cont)
Brainstem – midbrain, pons and
medulla oblongata
Midbrain – relay stimuli
concerning muscle movement
to other brain structures,
Pons – relays impulses to brain
centers Medulla oblongata –
reflex centers for controlling
involuntary functions of
breathing, sneezing,
swallowing, coughing, vomiting
and vasoconstriction.
Cerebellum –
separated from
cerebral cortex by
tentorium cerebelli

Coordinate movement,
equilibrium, muscle
tone and
proprioception.
Controls movement for
same side of body
(ipsilateral)
Anatomy and Physiology:
Brain (cont)
Blood flow
 Carotid arteries supply 80% to brain and
two vertebral arteries supply 20%
 Blood to cerebrum by posterior, middle
and anterior cerebral arteries
 Posterior and anterior communicating
arteries to circle of Willis
 Blood leaves brain through venous
sinuses into jugular veins
Anatomy and Physiology:
Spinal Cord

Spinal cord – continuation of medulla oblongata
Begins at foramen magnum and ends at L1/2
vertebrae
At L1/2 branches into lumbar and sacral nerve
roots ( cauda equina)
Nerve fibers transmit sensory, motor and
autonomic impulses between brain and body
Descending (motor) tracts carry impulses from
frontal lobe to muscles for voluntary movement
and play role in muscle tone and posture
Ascending (sensory) tracts carry sensory
information from body through thalamus to parietal
lobe
Anatomy and Physiology:
Peripheral Nervous System
Cranial Nerves
 12 pairs: 5 pairs (motor fibers only), 3 pairs (sensory
fibers only) and 4 pairs (motor and sensory fibers)
Spinal Nerves
 31 pairs: 8 pairs cervical, 12 pairs thoracic, 5 pairs
lumbar, 5 pairs sacral and 1 pair coccygeal
 First seven cervical nerves exit above corresponding
vertebrae
 Rest exit below corresponding vertebrae
 Motor fibers carry impulses from brain (frontal lobe)
through spinal cord to muscles and glands
 Sensory fibers carry impulses from sensory receptors
of body through spinal cord to brain (parietal lobe)
Anatomy and Physiology:
Peripheral Nervous System (cont)
Reflex Arc

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Response to sensory stimuli
Deep tendon reflexes – responses to stimulation of a
tendon that stretches neuromuscular spindles of a
muscle group
Strike a deep tendon reflex – stimulates sensory neuron that
travels to spinal cord – stimulates interneuron – stimulates
motor neuron to create movement
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Superficial reflexes tested in same manner
Each reflex corresponds to specific spinal segment
Anatomy and Physiology:
Autonomic Nervous System
Regulates body’s internal environment with
endocrine system

Sympathetic nervous system
Activated during stress (flight or fight response)
Increase blood pressure and heart rate, vasoconstricting
peripheral blood vessels, inhibits gastrointestinal peristalsis
and dilates bronchi

Parasympathetic nervous system
Controls vegetative functions (breed and feed)
Conserving energy: decrease heart rate and force of
myocardial contraction, decrease blood pressure and
respiration and stimulate gastrointestinal peristalsis
Anatomy and Physiology:
Gerontological Considerations
Dilation of ventricles
Cortical atrophy (greater
in frontal and temporal
lobes)
Decrease in brain weight
(decrease in neuron size)
Change in release of
neurotransmitter
Changes in motor
function – stooped,
forward-flexed posture
and slow gait
Loss of muscle strength
Changes in sensory and
motor function, memory, cognition
and proprioception
Decline in sensorimotor
function
Changes in eye-lens
thicken, smaller pupil size
Hearing loss (50% over 75)
Decrease in short term
memory
Decline in fluid intelligence
Slow reaction time
Health History: Present Health Status
Changes in ability to move around or participate
in usual activities
Any chronic diseases – Hypertension,
Myasthenia gravis, Multiple sclerosis
Chronic disease prevent maintaining healthy
lifestyle
Medications – anticonvulsant, antitremor,
antivertigo or pain medications
Alcohol consumption, legal or recreational
mood-altering drugs
Health History: Past History
Injury to head or spinal
cord. Residual changes
from experience
Surgery to brain, spinal
cord or any nerves.
Outcome of surgery
Stroke. Residual changes
Seizure disorder, type,
frequency, prevention
Health History: Family History
Stroke, seizures or tumor of brain or spinal cord
Risk Factors for Brain Attack
Non-modifiable
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Age
Gender
Family history
Race
Previous brain attack or heart attack
Modifiable
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Smoking
Control of Diabetes
Coronary artery disease
Transient ischemia attacks
Atrial fibrillation
High serum cholesterol
Obesity
Excessive alcohol intake
Cocaine use
Problem-Based History
Using symptom analysis or “OLD CARTS” for each of the following
symptoms
Headache, recent surgeries or medical procedures (spinal
anesthesia or lumbar puncture)
Dizziness or light headedness, difficulty keeping balance, feel like
may fall, associated with positional change or activity, sensation of
room spinning
Seizures, become unconscious, warning signs of impending seizure,
if unconscious – progress through body, change in color of face or
lips, loss of bowel or bladder control, length of time before back to
normal self, feelings afterwards, confused, headache or aching
muscles, sleep, factors that start seizure (stress, fatigue, activity or
stopping medication), methods initiated to prevent injury during
seizure, affect on your lifestyle, wear alert ID, occupation
Problem-Based History (cont)
Loss of Consciousness, blackout or faint –occurs suddenly, history
of diabetes, liver failure or kidney failure
Changes in movement – length of time had mobility change,
continuous or intermittent, tremors or shaking of hands or face,
affect of tremors or shaking on performance of ADL’s, history of
thyroid disease, twitches or sudden jerks, sense of weakness in or
difficulty moving parts of body, associated with an activity, problems
with coordination or keeping balance, lean to one side, legs give
way
Change in sensation – numbness or tingling, description of feeling,
associated with any activity
Dysphagia –length of time, involve liquids or solids or both,
excessive saliva or drooling, cough or choke when trying to swallow
Dysphasia/Aphasia – length of time, difficulty forming your words or
finding right words, understanding things said to you, change in
handwriting
Physical Examination
Many of the cranial nerves will be examined later under
the specific system, eg eyes etc. For this reason, we will
omit them here but they are considered indicative of
Neurological assessment.
Examination: Equipment
Aromatic material
Penlight
Tuning Fork
Cotton-tipped
applicator
Tongue blade
Disposable gloves
Paper clip
Cotton ball
Percussion hammer
Snellen’s chart
Glascow Coma Scale
Best eye opening response
Spontaneously
4
To verbal command
3
To pain
2
No response
1
Glascow Coma Scale cont
Best verbal response
Oriented, converses
5
Disoriented, converses
4
Inappropriate words
3
Incomprehensible sounds
2
No response
1
Glascow Coma Scale cont
Best motor response – to voice or pain
Obeys
6
Localizes pain
5
Flexion withdrawal
4
Flexion decorticate
3
Extension decerebrate 2
No response
1
Total
3-15
Physical Examination
Test cerebellar function for balance and
coordination
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General observation – gait of client walking across
room and turning around and walking back
Upper extremity
Tap thighs with hands using rapid pronation and supination
movements
Have client close eyes and stretch arms outward. Use index
fingers to alternately touch the nose rapidly.
Examine finger coordination by alternating movement of
fingers by having client touch each finger to thumb in rapid
sequence.
Have client rapidly move index finger back and forth between
his/her nose and your finger 18 inches apart
Coordination with Rapid Alternating
Movements
Coordination with Rapid Alternating
Movements
Examination of Finger Coordination
Fine Motor Function
Physical Examination (cont)
Test cerebellar function for balance and coordination
(cont)
Lower extremity
 With client in supine position, have them place
heel of one foot to the knee of other leg, sliding
it all the way down the shin.
 For all of the following, stand in front of client to
prevent falling:
Romberg test
Heel-toe walking a straight line
Hop in place on one foot
Walk on toes, then heels
Balance
Heel to Toe
Balance
Hopping on one
foot
Physical Examination (cont)
Evaluate extremities for muscle strength and
sensation
Evaluate extremities for deep tendon reflexes.
There are five deep tendon reflexes (triceps,
biceps, brachioradial, patellar and Achilles).
Refer to pg 630 in your textbook for the correct
method for position of the extremity and
placement of the reflex hammer. Scoring of deep
tendon reflexes are recorded from 0 = no
response to 4+ = brisk, hyperactive with
intermittent clonus. See Box 25-3 page 630 in
textbook.
Triceps Reflex
Biceps Reflex
Brachioradial Reflex
Patellar Reflex
Achilles Reflex
Plantar Reflex – Babinski sign
Verbalization of Findings
Client is a 55 yo white male who denies any
changes in ability to move or participate in usual
ADL’s. Denies any chronic diseases, only takes
multivitamin and low dose ASA. Denies alcohol
intake, tobacco or recreational or other moodaltering drugs. Has never had injury or surgery
to brain or spinal cord, stroke or seizure
disorder. No family history of stroke, seizures or
tumor of brain or spinal cord. Denies history of
headache, dizziness, seizures, loss of
consciousness, changes in movement or
sensation, dyspagia or dysphasia/aphasia.
Verbalization of Findings (cont)
Client speaks clearly with appropriate inflection and
sufficient volume to be heard. CN I – XII intact. (When
you are demonstrating each of these, you will identify the
name and number of the cranial nerve as well as what
you are examining.). Upright posture, gait smooth,
rhythmic and balanced as uses opposing arm swing.
Negative Romberg sign. Able to maintain balance when
walks heel to toe and hops on one foot. Maintains upper
extremity coordination with rapid alternating hand
movementand with finger to thumb sequence. Has fine
motor function. Maintains lower extremity coordination
with point to point testing. Differentiates sharp, dull and
light touch on arms and legs. Deep Tendon Reflexes
(DTR’s) bilaterally 2+. (When you perform the DTR’s,
you will identify each one and give the score for each
one as you compete it). Negative Babinski.