Chapter_024-Neurologic System.psdddddddddddddptx

Chapter 24
Neurologic System
Copyright © 2020 by Elsevier Inc. All rights reserved.

 Nervous system divided into two parts:
 Central nervous system (CNS), which includes brain
and spinal cord
 Peripheral nervous system (PNS), which includes all
nerve fibers outside brain and spinal cord
• Includes 12 pairs of cranial nerves, 31 pairs of spinal nerves,
and all their branches
• Carries sensory (afferent) messages to CNS from sensory
receptors
• Motor (efferent) messages from CNS to muscles and glands,
as well as autonomic messages that govern internal organs
and blood vessels
Structure and Function

Central Nervous System

 Cerebral cortex is cerebrum’s outer layer of nerve cells.
 Cerebral cortex is center of functions governing thought,
memory, reasoning, sensation, and voluntary
movement.
 Each half of cerebrum is hemisphere.
 Each hemisphere divided into four lobes: frontal, parietal,
temporal, and occipital
Cerebral Cortex

 Lobes have areas that mediate specific functions:
 Frontal lobe concerned with personality, behavior, emotions,
and intellectual function
• Broca’s area in frontal lobe mediates motor speech
 Parietal lobe’s postcentral gyrus is primary center for sensation
 Occipital lobe is primary visual receptor center
 Temporal lobe behind ear, has primary auditory reception
center, taste, and smell
• Wernicke’s area in temporal lobe associated with language
comprehension
Lobes of the Cerebral Cortex

 Damage to specific cortical areas produces a
corresponding loss of function:
 Motor weakness
 Paralysis
 Loss of sensation
 Impaired ability to understand and process language
 Damage occurs when highly specialized neurologic
cells are deprived of blood supply, such as when a
cerebral artery becomes occluded.
Damage to Cerebral Cortex

Cerebral Cortex

 Basal ganglia
 Gray matter in two cerebral hemispheres that form subcortical
associated motor system (extrapyramidal system)
 Thalamus
 Main relay station where sensory pathways of spinal cord, cerebellum,
and brainstem form synapses
 Hypothalamus
 Major respiratory center with basic function control and coordination
 Cerebellum
 Concerned with motor coordination and muscle tone of voluntary
movements
 Brainstem
 Central core of the brain—contains midbrain, pons and medulla
 Spinal cord
 Main pathway for ascending and descending fiber tracts that connect
brain to spinal nerves
Central Nervous System Components

 Crossed representation is notable feature of nerve
tracts.
 Left cerebral cortex receives sensory information from and
controls motor function to right side of the body.
 Right cerebral cortex likewise interacts with left side of body.
 Knowledge of where fibers cross midline will help
interpret clinical findings.
Pathways of CNS

 Sensation travels in afferent fibers in peripheral nerve
through posterior (dorsal) root and into spinal cord.
 There, may take one of two routes: anterolateral
(spinothalamic) tract or posterior (dorsal) columns
 Anterolateral tract
 Contains sensory fibers that transmit sensations of pain,
temperature, and crude or light touch
 Posterior (dorsal) columns
 These fibers conduct sensations of position, vibration, and
finely localized touch.
 Position (proprioception), vibration, and finely localized touch
(stereognosis)
Sensory Pathways

Sensory Pathways

 Corticospinal or pyramidal tract
 Fibers mediate voluntary movement, particularly very skilled,
discrete, purposeful movements.
 Motor nerve fibers travel to brainstem crossing to opposite,
contralateral side, (pyramidal decussation) and then pass down
in lateral column of spinal cord.
 Extrapyramidal tracts include
 motor nerve fibers originating in motor cortex, basal ganglia,
brainstem, and spinal cord outside pyramidal tract.
 subcortical motor fibers that maintain muscle tone and control
body movements, especially gross automatic movements, such
as walking.
Motor Pathways (1 of 2)

 Cerebellar system
 Coordinates movement, maintains equilibrium and
posture
 Receives information on position of muscles and
joints, body’s equilibrium, and kind of motor
messages sent from cortex to muscles
 Integrates information using feedback pathway to
exert control
Motor Pathways (2 of 2)

 Complex of descending motor fibers that can influence
or modify lower motor neurons
 Located completely within CNS; convey impulses from
motor areas of cerebral cortex to lower motor neurons
 Examples of upper motor neuron diseases are
cerebrovascular accident, cerebral palsy, and multiple
sclerosis.
Upper Motor Neurons

 Final common pathway, providing final contact with
muscle
 Located in anterior gray column of spinal cord, but
nerve fibers extend to muscle
 Movement must be translated into action by lower motor
neuron fibers.
 Examples of lower motor neurons are cranial nerves and spinal
nerves of peripheral nervous system.
 Examples of lower motor neuron diseases are spinal cord
lesions, poliomyelitis, and amyotrophic lateral sclerosis.
Lower Motor Neurons

Motor Pathways

 Reflexes: basic defense mechanisms of nervous
system
 Involuntary; below level of conscious control permitting quick
reaction to potentially painful or damaging situations
 Three types of reflexes:
 Stretch on/deep tendon (myotatic), e.g., knee jerk
• DTR has 5 components: intact sensory (afferent) nerve, functional
synapse in the cord, intact motor (efferent) nerve, neuromuscular
junction and competent muscle
 Superficial (cutaneous), e.g., plantar reflex
 Visceral (organ), e.g., pupillary response to light and
accommodation
Reflexes

Reflex Arc

 LMNs that enter and exit brain rather than spinal cord:
 CN I and II extend from cerebrum.
 Cranial nerves III to XII extend from midbrain and brainstem.
 12 pairs of cranial nerves supply primarily head and
neck, except vagus nerve, which travels to heart,
respiratory muscles, stomach, and gallbladder.
Cranial Nerves

 31 pairs of spinal nerves arise from length of spinal cord
and supply rest of body.
 Named for region of spine from which they exit
 8 cervical 12 thoracic, 5 lumbar, 5 sacral, and
1 coccygeal
 “Mixed” nerves
 Contain both sensory and motor fibers
 Each innervates particular segment of body.
 Dermal segmentation
 Cutaneous distribution of various spinal nerves
Spinal Nerves

 Dermatome
 Circumscribed skin area supplied mainly from one spinal cord
segment through particular nerve
 Dermatomes overlap; if one nerve is severed, most of
sensations are transmitted by one above and one below.
 Useful landmark dermatomes
 Thumb, middle finger, fifth finger are C6, C7, and C8
 Axilla at T1
 Nipple at T4
 Umbilicus at T10
 Groin in region of L1
 Knee at L4
Dermatomes

 Peripheral nervous system composed of cranial nerves
and spinal nerves
 Carry fibers divided functionally into two parts:
 Somatic fibers innervate skeletal (voluntary) muscles.
 Autonomic fibers innervate smooth (involuntary) muscles,
cardiac muscle, and glands.
 Autonomic system mediates unconscious activity.
Autonomic Nervous System

 Neurologic system is not completely developed at birth.
 Movement is directed primarily by primitive reflexes.
 Persistence of primitive reflexes is an indication of CNS
dysfunction.
 Sensory and motor development proceed with gradual
acquisition of myelin needed to conduct most impulses.
 As myelinization develops, infant is able to localize stimulus
more precisely and make more accurate motor response.
Developmental Competence:
Infants

 Atrophy with steady loss of neuron structure in brain
and spinal cord
 Velocity of nerve conduction decreases making reaction
time slower in some older persons.
 Increased delay at synapse results in diminished
sensation of touch, pain, taste, and smell.
 Motor system may show general slowing down of
movement, muscle strength, and agility decrease.
 Progressive decrease in cerebral blood flow and oxygen
consumption may cause dizziness and loss of balance.
Aging Adult

 Racial/ethnic disparity noted relative to strokes
 5th most common cause of death in the United States
 Screening for hyperlipidemia and HTN with statin treatment
 Geographic disparity noted relative to strokes
 Existence of “Stroke Belt” —8 states with increased stroke
mortality
 Nationwide burden of stroke
 Higher for African Americans and Hispanic populations
 Global concern
 Research evidence indicates that 90% of stroke burden due to
modifiable factors.
Culture and Genetics

 Headache
 Head injury
 Dizziness/vertigo
 Seizures
 Tremors
 Weakness
 Incoordination
 Numbness or tingling
 Difficulty swallowing
 Difficulty speaking
 Patient-centered care
 Environmental/occupational hazards
Subjective Data

 Headache: Ask about
 onset, frequency, and severity.
 location, quality description, and associated factors.
 Head injury: Ask about
 event history, type and description.
 loss of consciousness and recall of event.
 Dizziness/vertigo: Ask about
 onset, duration, description, and frequency.
 associated with change in position.
 vertigo characteristics—objective or subjective vertigo.
Subjective Data Questions (1 of 4)

 Seizures: Ask about
 course and duration.
 motor activity in body.
 associated clinical presentations.
 postictal phase.
 precipitating factors.
 medication therapy.
 coping strategies.
 Tremors: Ask about
 onset, type, duration, and frequency.
 precipitating and alleviating factors.
 Weakness: Ask about
 localized or generalized, distal or proximal.
 impact on mobility or ADLs.

 Incoordination: Ask about
 problems with balance while standing or ambulating.
 lateral drifting, stumbling, or falling.
 legs giving way and/or clumsy movements.
 Numbness or tingling: Ask about
 onset, duration, and location.
 whether it occurs with activity.
 Difficulty swallowing: Ask about
 With solids or liquids
 Drooling
 Difficulty speaking: Ask about
 onset, pattern, and duration.
 forming words or saying what you want to say.
 Patient-centered care: Ask about
 information regarding past pertinent medical history.

 Environmental and occupational hazards: Ask
about
 exposure history.
 medication history: Rx and OTC.
 alcohol history.
 substance abuse/drug history.

 Ask about
 maternal and/or fetal problems during pregnancy and delivery.
 gestational status, birth weight, and Apgar score.
 reflexes and motor performance.
 presence of seizure activity.
 meeting developmental milestones.
 environmental exposure to lead.
 learning problems identified.
 significant family history.
 participation in sports—injury history.
Additional History:
Infants and Children

 Dizziness: Ask about
 association with positional change or activity or medication.
 impact on ADLs.
 safety modifications.
 Memory: Ask about
 decrease in mental function or confusion.
 onset, duration, and frequency.
 Tremor: Ask about
 location.
 precipitating and alleviating factors.
 impact on ADLs.
 Sudden vision change: Ask about
 onset, duration, and frequency.
 loss of consciousness and safety.
 impact on ADLs.
Additional History: Aging Adult

 Perform screening neurologic examination on well persons with no
significant findings from history.
 Perform complete neurologic examination on persons with
neurologic concerns.
 Perform neurologic recheck examination on persons with
demonstrated neurologic deficits who require periodic
assessments.
 Integrate steps of neurologic examination with examination of
particular part of body.
 Use following sequence for complete neurologic examination:
• Mental status
• Cranial nerves
• Motor system
• Sensory system
• Reflexes
Objective Data: Preparation

 Penlight
 Tongue blade
 Cotton swab
 Cotton ball
 Tuning fork: 128 Hz or 256 Hz
 Percussion hammer
Objective Data: Equipment

 Cranial nerve I: olfactory nerve (not tested routinely)
 Test sense of smell in those who report loss of smell, head trauma,
and abnormal mental status, and when presence of intracranial lesion
suspected.
 Cranial nerve II: optic nerve
 Test visual acuity and visual fields by confrontation.
 Using ophthalmoscope, examine ocular fundus to determine color,
size, and shape of optic disc.
 Cranial nerves III, IV, and VI: oculomotor, trochlear, and abducens
nerves
 Check pupils for size, regularity, equality, direct and consensual light
reaction, and accommodation.
 Assess extraocular movements by cardinal positions of gaze.
 Assess for nystagmus.
Cranial Nerve Testing (1 of 5)

 Cranial nerve V: trigeminal nerve
 Motor function: assess muscles of mastication by palpating
temporal and masseter muscles as a person clenches his or
her teeth
 Sensory function: with a person’s eyes closed, test light touch
sensation by touching a cotton wisp to designated areas on a
person’s face: forehead, cheeks, and chin
 Assess corneal reflex if the person has abnormal facial
sensations or abnormalities of facial movement.
 Tests all three divisions of CN V: ophthalmic, maxillary, and
mandibular.

 Cranial nerve VII: facial nerve
 Motor function:
• Note mobility and facial symmetry as a person responds to
selected movements.
• Have the person puff cheeks, then press puffed cheeks in, to see
that air escapes equally from both sides
 Sensory function: (not tested routinely)
• Test only when you suspect facial nerve injury.
• When indicated, test sense of taste by applying cotton applicator
covered with solution of sugar, salt, or lemon juice to tongue and
ask the person to identify taste.
 Cranial nerve VIII: acoustic nerve (vestibulocochlear)
 Test hearing acuity by ability to hear normal conversation and
by whispered voice test.
37

 Cranial nerves IX and X: glossopharyngeal and vagus
nerves
 Motor function
• Depress tongue with tongue blade, and note pharyngeal movement
as the person says “ahhh” or yawns; uvula and soft palate should
rise in midline, and tonsillar pillars should move medially.
• Touch posterior pharyngeal wall with tongue blade, and note gag
reflex; voice should sound smooth, not strained.
 Sensory function
• Cranial nerve IX does mediate taste on posterior one third of
tongue, but technically too difficult to test.

 Cranial nerve XI: spinal accessory nerve
 Examine sternomastoid and trapezius muscles for equal size.
 Check equal strength by asking the person to rotate head
against resistance applied to side of chin.
 Ask the person to shrug shoulders against resistance.
 Cranial nerve XII: hypoglossal nerve
 Inspect tongue; no wasting or tremors should be present.
 Note forward thrust in midline as the person protrudes tongue.
 Ask the person to say “light, tight, dynamite,” and note that
lingual speech (sounds of letters l, t, d, n) is clear and distinct.

 Size
 Inspect all muscle groups for size noting bilateral comparison.
 Strength
 Test muscle groups of extremities, neck, and trunk.
 Tone: normal tension in relaxed muscles
 Persuade the person to relax completely, and move each
extremity smoothly through a full range of motion; normally
note mild, even resistance to movement.
 Involuntary movements
 Normally none occur; if present, note location, frequency, rate,
and amplitude; note if movements can be controlled at will.
Inspect and Palpate Motor System:
Muscles

 Rapid alternating movements (RAM)
 Ask the person to pat knees with both hands, lift up, turn hands
over, and pat knees with backs of hands; then ask the person
to do this faster.
• Normally done with equal turning and quick rhythmic pace
 Alternatively, ask the person to touch thumb to each finger on
same hand, starting with the index finger, then reverse
direction.
• Finger-to-finger test
• Finger-to-nose test
• Heel-to-shin test
Coordination and Skilled
Movements

 Balance tests
 Gait: observe as the person walks 10 to 20 feet, turns, and
returns to starting point
 Normally the person moves with a sense of freedom; gait is
smooth, rhythmic, and effortless; opposing arm swing is
coordinated; the person turns smooth; step length about 15
inches from heel to heel.
 Tandem walking: Ask the person to walk straight line in heel-to-
toe fashion
Cerebellar Function Tests (1 of 2)

 Romberg sign
 Ask the person to stand up with feet together and arms at
sides; when in stable position, ask the person to close eyes
and to hold position for about 20 seconds.
• Normally the person can maintain posture and balance even with
visual orienting information blocked.
 Ask the person to perform shallow knee bend or hop in place,
first on one leg, then other.
• Demonstrates normal position sense, muscle strength, and
cerebellar function
• Some individuals cannot hop because of aging or obesity.
Cerebellar Function Tests (2 of 2)

 Ask the person to identify various sensory stimuli
in order to test intactness of peripheral nerve
fibers, sensory tracts, and higher cortical
discrimination.
 Routine screening procedures include testing
superficial pain, light touch, and vibration in few distal
locations, and testing stereognosis.
 Complete testing of sensory system warranted in
those with neurologic symptoms (e.g., localized pain,
numbness, and tingling) or if you discover
abnormalities.
Assess Sensory System (1 of 2)

 Compare sensations on symmetric parts of
body.
 When you find definite decrease in sensation, map it
by systematic testing in that area.
 Proceed from point of decreased sensation toward
sensitive area; ask the person to tell you where
sensation changes; you can map exact borders of
deficient area; draw results on diagram.
 The person’s eyes should be closed during tests.
 Take time to explain what will be happening and
exactly how you expect the person to respond.
Assess Sensory System (2 of 2)

 Pain
 Tested by the person’s ability to perceive pinprick
 Temperature
 Test temperature sensation only when pain sensation is
abnormal; otherwise, you may omit it because the fiber tracts
are much the same.
 Light touch
 Apply wisp of cotton to skin in random order of sites and at
irregular intervals; include arms, forearms, hands, chest,
thighs, and legs; ask the person to say “now” or “yes” when
touch is felt.
 Compare symmetric points.
Anterolateral (Spinothalamic) Tract

 Vibration
 Test the person’s ability to feel vibrations of tuning fork over
bony prominences.
 Position (kinesthesia)
 Test the person’s ability to perceive passive movements of
extremities.
 Always check for bilateral comparison.
Posterior (Dorsal) Column
Tract (1 of 2)

 Tactile discrimination (fine touch): tests also measure
discrimination ability of sensory cortex.
 Stereognosis: test the person’s ability to recognize objects by
feeling their forms, sizes, and weights
 Graphesthesia: ability to “read” a number by having it traced on
skin
 Two-point discrimination: test ability to distinguish separation of
two simultaneous pin points on skin
 Extinction: simultaneously touch both sides of body at same
point; normally both sensations are felt
 Point location: touch skin and withdraw stimulus promptly; ask
the person to put finger where you touched
Posterior (Dorsal) Column
Tract (2 of 2)

 Measurement of stretch reflexes reveals intactness of
reflex arc at specific spinal levels and normal override
on reflex of higher cortical levels.
 Limb should be relaxed and muscle partially stretched.
 Stimulate reflex by directing short, snappy blow of reflex
hammer onto muscle’s insertion tendon.
 Bilateral comparison: responses should be equal
Deep Tendon Reflexes (DTRs)

 Reflex response graded on 4-point scale
 4 = very brisk, hyperactive with clonus, indicative of disease
 3 = brisker than average, may indicate disease
 2 = Average, normal
 1 = diminished, low normal, or occurs with reinforcement
 0 = no response
 Subjective scale requires clinical practice; scale not
completely reliable; a wide range of normal exists in
reflex responses.
 Reinforcement
 Alternate technique to help elicit reflexes by performing an
isometric exercise in a different muscle group.
 Must document that this technique was used.
DTRs 4-Point Scale

 Biceps reflex, C5 to C6
 Support the person’s forearm on yours; place your
thumb on biceps tendon and strike a blow on your
thumb.
• Normal response is contraction of biceps muscle and flexion
of forearm.
 Triceps reflex, C7 to C8
 Tell the person to let arm “just go dead” as you strike
triceps tendon directly just above the elbow.
• Normal response is extension of forearm.
Testing Reflexes (1 of 2)

 Brachioradialis reflex, C5 to C6
 Hold the person’s thumbs to suspend forearms in relaxation and
strike forearm directly, about 2 to 3 cm above radial styloid
process.
• Normal response is flexion and supination of forearm.
 Quadriceps reflex, L2 to L4 (knee jerk)
 Let lower legs dangle freely to flex knee and stretch tendons;
strike tendon directly just below patella.
• Normal response is extension of lower leg.
 Achilles reflex, L5 to S2 (ankle jerk)
 Position the person with knee flexed; hold foot in dorsiflexion and
strike Achilles tendon directly.
• Normal response is foot plantar flexes against your hand.
Testing Reflexes (2 of 2)

 Clonus: test when reflexes hyperactive
 Support lower leg in one hand and with other hand,
move foot up and down to relax muscle; then stretch
muscle by briskly dorsiflexing foot; hold the stretch.
• Normal response: you feel no further movement
• When clonus present, you will note rapid rhythmic
contractions of calf muscle and movement of foot.
• Sustained clonus is associated with UMN disease.
Clonus

 Superficial (cutaneous) reflexes
 Sensory receptors in skin rather than in muscles;
motor response is localized muscle contraction.
 Abdominal reflexes: upper: T8 to T10;
lower: T10 to T12
• Person in supine position, knees slightly bent; use handle
end of reflex hammer to stroke skin
• Move from each corner toward midline at both upper and
lower abdominal levels.
• Normal response is ipsilateral contraction of abdominal
muscle with observed deviation of umbilicus toward stroke.
Superficial Reflexes (1 of 2)

 Cremasteric reflex, L1 to L2 (not routinely done)
 On male, lightly stroke inner aspect of thigh with reflex
hammer or tongue blade.
• Note elevation of ipsilateral testicle.
 Plantar reflex, L4 to S2
 Position thigh with slight external rotation.
 With reflex hammer, draw a light stroke up lateral side of sole
of foot and inward across ball of foot, like an upside-down “J.”
• Normal response is plantar flexion of toes and inversion and
flexion of forefoot.
Superficial Reflexes (2 of 2)

 Abbreviation of neurological exam for head trauma or
neurological deficit caused by systemic disease
 Level of consciousness—change in LOC—perform relative
assessments
 Motor function—check voluntary movement of each extremity by
giving specific commands
 Pupillary response—check for PERLA noting size in millimeters
 Vital signs—measure and monitor
• Glasgow coma scale—eye opening, motor and verbal response—
quantitative measurement tool to assess LOC
• Diabetic neuropathy screening—monofilament test—standardized
measurement tool to detect peripheral neuropathy
Neurological Recheck

Glasgow Coma Scale

 Note developmental milestones and disappearance of primitive
reflexes.
 Behavioral assessment includes observations of infant’s interaction
with the environment.
 Motor system
 Screen gross and fine motor coordination using Denver II test with its
age-specific developmental milestones.
 Sensory system
 You will perform very little sensory testing with infants and toddlers.
 Reflexes
 Infantile automatisms: reflexes that have predictable timetable of
appearance and departure
 For screening examination, check rooting, grasp, tonic neck, and Moro
reflexes.
Infants

 Rooting reflex: brush the infant’s cheek near mouth; note whether
infant turns head toward that side and opens mouth
 Appears at birth; disappears at 3 to 4 months
 Palmar grasp: place baby’s head midline to ensure symmetric
response; offer finger from baby’s ulnar side, away from thumb;
note tight grasp of all baby’s fingers
 Present at birth; strongest at 1 to 2 months; disappears at 3 to 4
months
 Plantar grasp: touch your thumb at ball of baby’s foot; note that toes
curl down tightly
 Reflex present at birth; disappears at 8 to 10 months
Infant Reflexes (1 of 2)

 Tonic neck reflex: with baby supine, turn head to one side with chin
over shoulder; note ipsilateral extension of arm and leg, and flexion
of opposite arm and leg; the “fencing” position
 Appears by 2 to 3 months; decreases at 3 to 4 months; disappears by
4 to 6 months
 Moro reflex: startle infant by jarring crib, making a loud noise, or
supporting head and back in semi-sitting position and quickly
lowering infant to 30 degrees
 Present at birth; disappears at 1 to 4 months
 Placing reflex: hold infant up next to table—able to place foot on
table
 Reflex appears at 4 days after birth
 Stepping reflex: hold infant on flat surface—note regular alternating
steps
 Reflex disappears before voluntary walking.
Infant Reflexes (2 of 2)

 Assess the child’s general behavior during play activities,
reaction to parent, and cooperation with parent and with you.
 Much of motor assessment can be derived from watching
child undress and dress and manipulate buttons; indicates
muscle strength, symmetry, joint range of motion, and fine
motor skills.
 Use Denver II to screen gross and fine motor skills
appropriate for child’s age.
 Note child’s gait both walking and running; allow for normal
wide-based gate of toddler and normal knock-kneed walk of
preschooler.
Developmental Competence: Preschool
and School-Age Children (1 of 3)

 Observe child as rising from supine position to sitting position, then
to a stand; note muscles of neck, arms, legs, and abdomen.
 Normally child curls up midline to sit up, then pushes off with both
hands against floor to stand.
 Assess fine coordination using finger-to-nose test.
 Demonstrate procedure first, then ask child to do test with the eyes
open, then with eyes closed.
 Fine coordination not fully developed until child is 4 to 6 years;
consider it normal if younger child can bring finger to within 2 to 5 cm
of nose.
 Testing sensation very unreliable in toddlers and preschoolers
 May test light touch by asking child to close eyes and point to spot
where you touch

 When you need to test DTRs in young child, use your
finger to percuss tendon.
 Use reflex hammer only with an older child; coax child
to relax, or distract and percuss discreetly when child
not paying attention.
 Knee jerk present at birth; then ankle jerk and brachial
reflex appear; and triceps reflex present by 6 months

 Use same examination as with younger adults.
 Cranial nerves mediating taste and smell not usually
tested, may show some decline in function
 Decrease in muscle bulk most apparent in hand
 Dorsal hand muscles often look wasted, even with no apparent
arthropathy.
 Grip strength remains relatively good.
 Senile tremors occasionally occur.
 Benign tremors include an intention tremor of hands, head
nodding, and tongue protrusion.
Aging Adult (1 of 3)

 Dyskinesias: repetitive stereotyped movements in jaw, lips, or
tongue may accompany senile tremors; no associated rigidity
present
 Gait may be slower and more deliberate than in a younger person;
may deviate from midline path.
 RAMs Rapid alternating movements may be difficult to perform
 Loss of sensation and increased stimulus needed to elicit a
response.
 After 65 years of age, loss of sensation of vibration at ankle malleolus
common; loss of ankle jerk; tactile sensation may be impaired; may
need stronger stimuli for light touch; and especially for pain.

 DTRs less brisk; those in upper extremities usually
present, but ankle jerk commonly lost; knee jerks may
be lost; because aging people find it difficult to relax
limbs, always use reinforcement when eliciting DTRs
 Plantar reflex may be absent or difficult to interpret; often, you
will not see a definite normal flexor response; still should
consider definite extensor response abnormal.
 Superficial abdominal reflexes may be absent, probably
because of stretching of musculature through pregnancy or
obesity.

 F.A.S.T. plan—American Heart Association
 F = Face drooping
 A = Arm weakness
 S = Speech difficulty
 T = Time to call 9-1-1
 Review of risk factors:
 HTN
 Cigarette smoking
 Heart disorders
 Vaccination to reduce risk for Herpes Zoster (shingles) in
older adult
Health Promotion and Teaching

 Memory loss
 Losing track
 Forgetting words
 Getting lost
 Poor judgment
 Abstract failing
 Losing things
 Mood swings
 Personality change
 Growing passive
Warning Signs of Alzheimer Disease

 CN I, olfactory nerve
 Anosmia
 CN II, optic nerve
 Defect or absent central vision
 Defect in peripheral vision, hemianopsia
 Absent light reflex
 Papilledema
 Optic atrophy
 Retinal lesions
Abnormalities in
Cranial Nerves (1 of 4)

 CN III, oculomotor nerve
 Dilated pupil, ptosis, eye turns out and slightly down
 Failure to move eye up, in, down
 Absent light reflex
 CN IV, trochlear nerve
 Failure to turn eye down or out
 CN V, trigeminal nerve
 Absent touch and pain, paresthesias
 No blink
 Weakness of masseter or temporalis muscles
Abnormalities in

 CN VI, abducens nerve
 Failure to move laterally, diplopia on lateral gaze
 CN VII, facial nerve
 Absent or asymmetric facial movement
 Loss of taste
 CN VIII, acoustic nerve
 Decrease or loss of hearing
 CN IX, glossopharyngeal nerve
 No gag reflex
Abnormalities in

 CN X, vagus nerve
 Uvula deviates to side
 No gag reflex
 Voice quality:
• Hoarse or brassy, nasal twang or husky
 Dysphagia, fluids regurgitate through nose
 CN XI, spinal accessory nerve
 Absent movement of sternomastoid or trapezius muscles
 CN XII, hypoglossal nerve
 Tongue deviates to side.
 Slowed rate of tongue movement
Abnormalities in

 Flaccidity
 Spasticity
 Rigidity
 Cogwheel rigidity
Abnormalities in Muscle Tone

 Paralysis
 Fasciculations
 Tic
 Myoclonus
 Chorea
 Athetosis
 Seizure disorder
 Tremor
 Rest tremor
 Intention tremor
Abnormalities in Muscle Movement

 Spastic hemiparesis
 Cerebellar ataxia
 Parkinsonian (festinating)
 Scissors
 Steppage or footdrop
 Waddling
 Short leg
Abnormal Gaits

 Weakness/paralysis
 Location
 Example
 Muscle tone bulk
 Abnormal movements/reflexes
 Possible nursing diagnoses
Characteristics of UMN and LMN
Lesions

 Cerebral palsy
 Muscular dystrophy
 Hemiplegia
 Parkinsonism
 Cerebellar
 Paraplegia
 Multiple sclerosis
Patterns of Motor System Dysfunction

 Peripheral neuropathy
 Loss of sensation involves all modalities; loss most severe
distally at feet and hands.
 Individual nerves or roots
 Decrease or loss of all sensory modalities; corresponds to
distribution of involved nerve
 Spinal cord hemisection (Brown-Séquard syndrome)
 Loss of pain and temperature, contralateral side, loss of
vibration and position discrimination on ipsilateral side
Patterns of Sensory Loss (1 of 2)

 Acute compression of spinal cord
 Symmetric loss of sensation under a circumferential boundary
 Thalamus
 Loss of all sensory modalities on face, arm, and leg;
contralateral to lesion
 Cortex
 Loss of discrimination on contralateral side; loss of
graphesthesia, stereognosis, recognition of shapes and
weights, finger finding
Patterns of Sensory Loss (2 of 2)

 Decorticate rigidity
 Upper extremities
• Flexion of arm, wrist, and fingers
• Adduction of arm: tight against thorax
 Lower extremities
• Extension, internal rotation, plantar flexion; indicates hemispheric
lesion of cerebral cortex
 Decerebrate rigidity
 Upper extremities: stiffly extended, adducted, internal rotation,
palms pronated
 Lower extremities: stiffly extended, plantar flexion; teeth
clenched; hyperextended back
• More ominous than decorticate rigidity; indicates lesion in
brainstem at midbrain or upper pons
Abnormal Postures (1 of 2)

 Flaccid quadriplegia
 Complete loss of muscle tone and paralysis of all
four extremities, indicating nonfunctional brainstem
 Opisthotonos
 Prolonged arching of back, with head and heels
bent backward; indicates meningeal irritation
Abnormal Postures (2 of 2)

 Babinski
 Oppenheim
 Gordon Hoffmann
 Kernig
 Brudzinski
Pathologic Reflexes

 Snout reflex
 Sucking reflex
 Grasp reflex
Frontal Release Signs

Summary Checklist: Neurologic
Examination
Screening and complete
 Mental status
 Cranial nerves
 Motor function
 Sensory function
 Reflexes

Chapter_024-Neurologic System.psdddddddddddddptx

More Related Content

Similar to Chapter_024-Neurologic System.psdddddddddddddptx (20)

Recently uploaded (20)

Chapter_024-Neurologic System.psdddddddddddddptx