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Cerebrovascular Accident/Stroke
=INTRODUCTION=

Cerebrovascular accidents (CVAs), or strokes, continue to be a national health problem despite recent advances in medical
technology

Stroke ranks as the third leading cause of death behind heart disease and cancer
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S
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
Each year, 795,000 people suffer a new or recurrent stroke
...
For people older than 55, the incidence of stroke more than doubles
with each successive decade

The incidence of stroke is about 1
...

- left CVA = right hemiplegia
- right CVA = left hemiplegia
- accompanying dysfunctions:
- sensory disturbances
- cognitive and perceptual dysfunction
- visual disturbances
- personality and intellectual changes
- complex range of speech and associated language disorders
- neurologic deficits must persist longer than 24 hours to be labeled a CVA
=ANATOMY=
BRAIN
> The two cerebral hemispheres are divided into four lobes: frontal, parietal, occipital, and temporal
...

- All behavioral motor output originating in the frontal lobe, including mobility, object manipulation, directional eye
movement, and verbal expression, are assisted by the basal ganglia and cerebellum
...

> There are also significant interconnections between primary motor cortex and somatosensory cortex, premotor and ventral motor
areas, as well as connections from the thalamus to the motor cortex and from the motor cortex to the basal ganglia,
superior and inferior colliculi, and cerebellum
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falx cerebelli - separates the two hemispheres of the cerebellum
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- It also contains many nuclei and ascending and descending nerve fibers
Cerebellum
- situated on:
= posterior cranial fossa of the skull
= posterior to the pons and the medulla oblongata
- consists of two laterally placed hemispheres connected by a median portion, the vermis
- connected to:
= midbrain by superior cerebellar peduncles
= pons by the middle cerebellar peduncles
= medulla by the inferior cerebellar peduncles
Midbrain - narrow part of the brain that connects the forebrain to the hindbrain
Forebrain
Diencephalon
- almost completely hidden from the surface of the brain
- consists of:
> dorsal thalamus
> ventral hypothalamus
Cerebrum
- largest part of the brain
- consists of two cerebral hemispheres
- corpus callosum – a mass of white matter that connects the two cerebral hemispheres
-Brainstem
> collective term for the medulla oblongata, pons, and midbrain
> part of the brain that remains after the cerebral hemispheres and cerebellum are removed
CIRCLE OF WILLIS
- is a confluence (actually a hexagon) of vessels that gives rise to all of the major cerebral arteries
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anterior cerebral artery- The anterior cerebral artery thus supplies the “leg area” of the precentral gyrus
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MCA- Cortical branches supply the entire lateral surface of the hemisphere, except for the narrow strip supplied by the anterior cerebral artery,
the occipital pole, and the inferolateral surface of the hemisphere, which are supplied by the posterior cerebral artery This artery thus supplies
all the motor area except the “leg area
...

anterior inferior cerebellar artery passes posteriorly and laterally and supplies the anterior and inferior parts of the cerebellum
superior cerebellar artery- It also supplies the pons, the pineal gland
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Age
1
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Those
2
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Race
pressure
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Ethnicity
2
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Heredity
abnormalities (patent foramen ovale and atrial septal aneurysm), can reduce the risk for stroke
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Management of diabetes and glucose metabolism can also reduce the risk for stroke
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Cigarette smoking increases the relative risk for ischemic stroke nearly two times
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Although excessive use of alcohol is a risk factor for many other diseases, moderate consumption of
alcohol may reduce the incidence of cardiovascular disease, including stroke
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Use of illegal drugs, particularly cocaine, is commonly associated with stroke
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7
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- Pathophysio
> disruption of the cerebral blood flow due to obstruction of a blood vessel
> disruption in blood flow initiates a complex series of cellular metabolic events referred to as the ischemic cascade
- begins when cerebral blood flow falls to less than 25 mL/100 g/min
- At this point, neurons can no longer maintain aerobic respiration
- The mitochondria must then switch to anaerobic respiration, which generates large amounts of lactic acid, causing a
change in the pH level
- This switch to the less efficient anaerobic respiration also renders the neuron incapable of producing sufficient quantities
of adenosine triphosphate (ATP) to fuel the depolarization processes
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- S/Sx:
> Numbness or weakness of the face, arm, or leg, especially on one side of the body
> Confusion or change in mental status
> Trouble speaking or understanding speech
> Visual disturbances
> Difficulty walking, dizziness, or loss of balance or coordination
> Sudden severe headache
HEMORRHAGE
- Hemorrhagic strokes
- subarachnoid and intracerebral hemorrhages, which account for only 13% of the total number of strokes
- CAUSES:
> deep hypertensive intracerebral hemorrhages
> ruptured saccular aneurysms
> bleeding from arteriovenous malformations
> spontaneous lobar hemorrhages
- Pathophysiology
> depends on the cause and type of cerebrovascular disorder
> Symptoms are produced when an aneurysm or AVM enlarges and presses on nearby cranial nerves or brain tissue or, more
dramatically, when an aneurysm or AVM ruptures, causing subarachnoid hemorrhage (hemorrhage into the cranial
subarachnoid space)
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RELATED SYNDROMES
- Cerebral anoxia and aneurysm can also result in hemiplegia
- other causes of hemiplegia:
> head injuries
> neoplasms
> infectious diseases of the brain

TRANSIENT ISCHEMIC ATTACKS
- characterized by mild, isolated, or repetitive neurologic symptoms that develop suddenly, last from a few minutes to several hours but not
longer than 24 hours, and clear completely
- seen as a sign of an impending stroke
- Most TIAs occur in people with atherosclerotic disease
=EFFECTS OF STROKE=
- Diagnostic Tools:
> computed tomography (CT)
> magnetic resonance imaging (MRI)
> positron emission tomography (PET)
> single-photon emission computed tomography (SPECT)
INTERNAL CAROTID ARTERY
- absence of adequate collateral circulation, occlusion:
> contralateral hemiplegia
> hemianesthesia
> homonymous hemianopia
- involvement of the dominant hemisphere associated with:
> aphasia
>agraphia or dysgraphia
> acalculia or dyscalculia
> right-left confusion
> finger agnosia
- Involvement of the nondominant hemisphere associated with:
> visual perceptual dysfunction
> unilateral neglect
> anosognosia
> constructional or dressing apraxia
> attention deficits
> loss of topographic memory
MIDDLE CEREBRAL ARTERY
- most common cause of stroke
- results of ischemia in MCA:
> contralateral hemiplegia with greater involvement of the arm, face, and tongue;
> sensory deficits
> contralateral homonymous hemianopia
> aphasia - lesion is in the dominant hemisphere
- pronounced deviation of the head and neck toward the side on which the lesion is located
- Perceptual deficits in in the nondominant hemisphere lesion:
> anosognosia
> unilateral neglect
> impaired vertical perception
> visual spatial deficits
> perseveration
*** TABLE 33-1: upper trunk, lower trunk and both
ANTERIOR CEREBRAL ARTERY
- OCCLUSION: contralateral lower extremity weakness that is more severe than that of the arm
> Apraxia
> mental changes
> primitive reflexes
> bowel and bladder incontinence may be present
- TOTAL OCLUSION
> contralateral hemiplegia with severe weakness of the face, tongue, and proximal arm muscles
> marked spastic paralysis of the distal end of the lower extremity
- Cortical sensory loss – present in LE
- Intellectual changes:
> confusion
> disorientation
> abulia
> whispering

> slowness
> distractibility
> limited verbal output
> perseveration
> amnesia
POSTERIOR CEREBRAL ARTERY
- symptoms is potentially broad and varied because this artery supplies the upper brainstem region, as well as the temporal and occipital lobes
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g
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Other important but less common stroke symptoms include:
Sudden nausea, fever, and vomiting distinguished from a viral illness by the speed of onset (minutes or hours vs several days)
Brief loss of consciousness or a period of decreased consciousness (fainting, confusion, convulsions, or coma)
Face, Arms, Speech Test
F = FACE: ask the person to smile – do both sides of the face move equally? (Normal) Or does one side of the face not move at all? (Abnormal)
A = ARM: ask the person to raise both arms – do both arms move equally? (Normal) Or does one arm drift downward compared to the other?
(Abnormal)
S = SPEECH: ask the person to speak a simple sentence – Does the person use correct words with no slurring? (Normal) Or do they slur their
speech, use inappropriate words or is unable to speak at all? (Abnormal)
T = TIME: to call 911 – if you observe any of these symptoms, call 911 immediately
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- neurologic recovery and functional recovery are different aspects to consider
Client-Centered Assessments
- Client-centered practice
> approach to providing occupational therapy which embraces a philosophy of respect for, and partnership with, people receiving
services
> concepts:
1
...
Offering the client a more active role in defining goals and desired outcomes
3
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Shifting to a model in which occupational therapists work with clients to enable them to meet their own goals
5
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Allowing the client to be the “problem definer” so that the client will in turn become the “problem solver”
7
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Inquiry into role competency and meaningfulness is the starting point for evaluation
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Inquiry is focused on the roles that are important to the client who sustained a stroke, particularly those in which the client was
engaged before the stroke
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Any discrepancy of roles in the past, present, or future is identified to help determine a treatment plan
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The tasks that define a person are identified, as well as whether those tasks can be performed and the reasons that the tasks are
problematic
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A connection is determined between the components of function and occupational performance
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g
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g
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g
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• Create an environment that includes the common challenges of everyday life
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• Provide opportunities for practice outside therapy time (e
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, homework assignments)
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=Functional Limitations Commonly Observed after Stroke=
Inability to Perform Chosen Occupations While Seated
Loss of trunk and postural control - commonly observed deficit after stroke
> Problems:
1
...
Increased risk for falls
3
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Visual dysfunction secondary to resultant head and neck malalignment
5
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Decreased independence in ADLs
> Manifestations:
- inability to sit in proper alignment
- loss of righting and equilibrium reactions
- inability to reach beyond the arm span because of lack of postural adjustments
- falling during attempts to function
>need to use the more functional UE for postural support to remain upright and prevent falls
Trunk Control
- an obvious prerequisite for the control of more complex limb activities that in turn constitute a prerequisite to complex behavioral skills
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Inability to perceive the midline as a result of spatial relationship dysfunction and leading to sitting postures that are misaligned
from the vertical
2
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g
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Multidirectional trunk weakness
4
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Inability to move the trunk segmentally (i
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, the trunk moves as unit; examples of this phenomenon are clients using “logrolling”
patterns during bed mobility and an inability to rotate the trunk while reaching for an item across the midline)
6
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upright standing postures
- characterized by asymmetric weight distribution
- weight distribution while standing is seen through the lower extremities
Reasons inability to bear weight through the affected leg:
> fear of falling or buckling of the knee
> patterns of weakness that will not support the weight of the body
> spasticity impeding proper alignment (i
...
, plantar flexion spasticity that effectively blocks weight bearing through the sole of the
foot)
> perceptual dysfunction
Ankle Strategies
- used to maintain the center of mass over the base of support when movement is centered on the ankles
- control small, slow, swaying motions such as standing in a movie line, engaging in conversations while standing, and stirring a pot on a
stovetop
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g
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- contribute to ineffective ankle strategies and balance:
> Ankle weakness
> loss of ankle ROM
> proprioceptive deficits
Hip strategies
- used to maintain or restore equilibrium
- used specifically in:
> response to larger, faster perturbations, when the support surface is compliant
> when the surface is smaller than the feet (e
...
, walking on a beam)
Stepping Strategies
- used when ankle and hip strategies are ineffective or are perceived to be ineffective
- results in movement of the base of support toward the center of mass movement
- A step is taken to widen the base of support
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Syntactic structure
- simplified because of the agrammatism,
- sometimes referred to as telegraphic speech
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Wernicke’s Aphasia
- impaired auditory comprehension and feedback, along with fluent, well-articulated paraphasic speech
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- Speech may occur at an excessive rate and may be hyperfluent
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- The client produces running speech composed of English words in a meaningless sequence
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- Reading and writing comprehension is often limited
- mathematic skills may be impaired

Anomic Aphasia
- difficulty in word retrieval
- Anomia, or word-finding difficulty - occurs in all types of aphasia
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- Mild to severe deficits in reading comprehension and written expression occur, and mild deficits in mathematic skills may be present
Dysarthria
- an articulation disorder
- absence of aphasia, because of dysfunction of the CNS mechanisms that control the speech musculature
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Extra noise creates confusion
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• Carefully phrase questions to make it easier for the client to respond; for example, use “yes/no” and “either/or” questions
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• Never force a response
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• Do not rush communication because this may increase frustration and decrease the effectiveness of communication
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g
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- very far transfer
> spontaneous application of what has been learned in treatment to everyday living
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Pain
2
...
Loss of selective motor control
4
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Superimposed orthopedic limitations

6
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Learned nonuse
8
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Inefficient and ineffective movement patterns
Integration into Function
- Standardized evaluations - objectively measure the client’s ability to use the affected extremity during performance of tasks
> Test d’Evaluation des Membres Supérieurs de Personnes Agées (TEMPA)
> Arm Motor Ability Test (AMAT)
> Jebsen Test of Hand Function
> AMPS
- self-reported measures of UE function
> Motor Activity Log
- reported by the patient or family
- six-point scale
- actual use of the involved UE outside structured therapy time
> 36-item Manual Ability Measure (MAM-36)
- Rasch-developed, self-reported disability outcome measure
- 36 gender-neutral, commonly performed everyday hand tasks
- four-point rating scale
- Upper Extremity Complications after Stroke Subluxation
Subluxation, or malalignment - caused by instability of the glenohumeral
> Types
- inferior (head of the humerus below the glenoid fossa)
= result of malalignment of the scapula and the trunk
- anterior (head of the humerus anterior to the fossa)
- superior (head of the humerus lodged under the acromion-coracoid)
> Tx: reduce subluxation should focus on achieving trunk alignment and scapula stability in a position of upward rotation
- support the flail shoulder in bed (e
...
, using pillows to maintain alignment)
- wheelchair (e
...
, with lap boards or pillows)
- upright position (e
...
, putting the hands in a pocket or taping the shoulder)
- Abnormal Skeletal Muscle Activity
low-tone stage
- acute state
- characterized by low tone
- limbs and trunk become increasingly influenced by the pull of gravity
- Little or no muscle activity
- Problems:
> edema
> Overstretching of the joint capsule of the glenohumeral joint
> Eventual shortening of muscles
> Overstretching of the antagonists
> Risk of joint and soft tissue injury during ADLs and mobility tasks
Progression to a state of increased or excessive skeletal muscle activity (increased tone
> clonus
> stereotypic posturing of the trunk and limbs
> hyperactive stretch reflexes
> increased resistance to passive limb movements that are dependent on velocity
- Prevention of Pain Syndromes and Contracture Protection of Unstable Joints
low-tone stage - joints tend to become malaligned secondary to loss of muscular stabilization
impingement syndrome - unstable glenohumeral joint is in a malaligned state
Key joint motions of concern:
> upward rotation of the scapula
> external (lateral) rotation of the shoulder
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- Soft Tissue Elongation
low-load prolonged stretch (LLPS)
- placing the soft tissues in question on submaximal stretch for prolonged periods
- program: - prevent contracture
> client rest in a supine position
> arm abducted to 45 degrees
> external rotation

- Splinting
Purpose during low-tone stage:
> maintaining joint alignment
> protecting the tissues from shortening or overstretching
> preventing injury to the extremity
> serving as an adjunctive treatment to control edema
> provide palmar arch support
> maintain neutral wrist deviation
> neutral position of the wrist between flexion and extension
effective for clients in whom spasticity is developing
- Client Management
Low tone - most important information to share with the client and significant others is the method for protecting the unstable joints and
maintaining full ROM
spastic stage - teach positioning that will provide prolonged elongation of the overactive muscles and prevent contracture
positions that may be prescribed during leisure or selfcare activities include the following:
1
...
In the supine position, hands behind the head while allowing the elbows to drop toward the bed (provides stretch of the internal rotators)
3
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Lying on a protracted scapula to maintain stretch of the retractors and scapulothoracic mobility
5
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)
6
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Cautionary note: Clasping the hands and lifting the affected arm overhead should be discouraged because of the risk for increasing
pain, causing an impingement syndrome, and stressing the carpal ligaments (Figure 33-8)
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The Nonfunctional Upper Extremity
- one-handed techniques
- prescription of appropriate assistive devices
- dominance retraining
- Control of deformity
Inability to Perform Chosen Tasks Secondary to Visual Impairment
Processing of visual information - complex act that requires intact functioning of multiple peripheral nervous system and CNS structures to
support functional independence
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