Exam 2 Flashcards
Stroke Death Prevelence
- stroke kills almost 130,000 americans each year
- 1 out of every 19 deaths
- every year, more than 795,000 people in the US have stroke
- 185,000 strokes (1 in 4) are people who have had previous stroke
- stroke is a leading cause of serious long-term disability
Risk factors of Stroke that CANNOT be changed
- age: risk doubles for each decade of life after age 55
- gender: more common in men than women, women use of birth control pills and pregnancy pose stroke risks though
- prior stroke, TIA, or heart attack: person with 1+ TIA is 10X more likely to have a stroke than someone of same age/gender. if patient has had heart attack, 3X higher risk of having a stroke
TIA
- transient ischemic attack
- aka “mini stroke’
Can stroke risk be influenced by race and ethnicity?
- YES
- risk of first stroke is nearly twice as high for African Americans and African American’s are more likely to die following a stroke than caucasians
- hispanic americans’ risk for stroke falls between caucasians and african americans
CVA Risk Factors that CANNOT be changed but CAN be TREATED or controlled
- sickle cell anemia
- african american and hispanic children more common
- sickle cells tend to stick to blood vessel walls, which block arteries and cause a stroke
CVA Risk factors that CAN be CHANGED, TREATED, AND CONTROLLED
- high blood pressure
- cigarette smoking
- diabetes mellitus
- carotid or other artery disease (peripheral)
- atrial fibrillation
- high blood cholesterol
- poor diet
- physical inactivity/obesity
Carotid artery
- narrowed by atherosclerosis
- plaque builds up in artery walls
- may become blocked by blood clot
Peripheral Artery Disease
- narrowing of blood vessels carrying blood to leg and arm muscles
- plaque in artery walls
- higher risk of artery disease and therefore stroke
Poor Diet that increases stroke risk
- high in saturated fat and cholesterol
- high sodium (salt)
- diets with excess calories > obesity
- 5+ servings of fruits and vegetables per day may reduce the risk of stroke
Physical inactivity and obesity effects on stroke
- being inactive, obese, or both can increase risk of high blood pressure, high blood cholesterol, diabetes, heart disease, and stroke
- recommendation: at least 30 minutes of activity on most or all days
Ischemic Prevelence with strokes
- ischemic: lack of blood
- 83-87% of all strokes are ischemic strokes, when blood flow to brain is blocked
Two types of ischemic strokes
- cerebral thrombus
- cerebral embolism
Cerebral Thrombus
- type of ischemic stroke
- blood vessel narrows
- from atherosclerosis
- thrombosis = blood clot
Cerebral embolism
- type of ischemic stroke
- clot from heart, upper body, or neck dislodges and move to brain and blocks artery
DVT
- deep vein thrombosis
- expect swelling, red and warm to touch, paon
- don’t vigorously exercise with DVT!
Hemorrhagic Stroke
- 17% of all strokes
- weakened vessel that ruptures and bleeds into the surrounding brain
- blood accumulates and compresses the surrounding brain tissue
- weakened blood vessels are from aneurysms or arteriovenous malformations (AVMs)
Aneurysm
- ballooning of a weakened region of a blood vessel
Arteriovenous Malformation (AVM)
- a cluster of abnormally formed blood vessels
- the vessels can rupture, causing bleeding into the brain
MCA
- middle cerebral artery
- most common stroke location
Areas affected by a MCA stroke
- optic radiation = homonymous hemianopia (contralateral visual fields cut)
- broca’s and wernicke’s area = expressive and receptive aphasia
- motor and sensory homunculus
Broca’s Area #
44
Wernicke’s Area #
22
Homonymous Hemianopsia
- due to a stroke involving the optic tract or radiations on the opposite side
- usually from MCA
- homonymous hemianopsia is when you cannot see the same 1/2 of each eye (i.e. both eyes lose their field of vision of the R side)
Unilateral optic field loss
- i.e. left optic nerve compression
- this is when you can see completely out of one eye but not at all out of the other
- eye that is blind is one with nerve compression
Bitemporal hemianopia
- chiasmal compression from “pituitary tumor”
- means both the outside/lateral visual fields are blinded/blocked
Contralateral Hemiparesis and Sensory impairment due to MIDDLE Cerebral Artery affects what areas first
- arm > leg
Apraxia
- can be caused by MCA stroke
- inability to plan or carry out a motor plan
- ideomotor apraxia
- ideational apraxia
What does the MCA supply?
- supplied internal capsule and basal ganglia
- damage will result in both UE and LE involvement
- remember: internal capsule deals with a lot of motor output
Contralateral Hemiparesis and Sensory impairment due to ANTERIOR cerebral artery affects what areas first
- leg > arm
Anterior Cerebral Artery Stroke impairments
- contralateral hemiparesis
- contralateral sensory impairments
- loss of bowel/bladder control
- apraxia
- mental impairment with perseveration, confusion, memory loss
Perseveration
- do the same thing or say the same words repeatedly
Posterior Cerebral Artery Stroke Impairments
- contralateral homonymous hemianopia
- Dyslexia
- Memory deficits
- Topographical disorientation
- cranial nerve III Palsy (oculomotor)
- contralateral hemiparesis
- Thalamic Syndrome
Thalamic Syndrome
- can be due to posterior cerebral artery stroke
- sensory impairments in all modalities
- pain
- paresthesias
- pain and temperature sensory loss
- ataxia, athetosis, choreiform movement
- visual agnosia: not recognizing familiar object with vision
- tactile agnosia: not recognizing object based touch
Dyslexia
- learning disorder characterized by difficulty reading due to problems identifying speech sounds and learning how they relate to letters and words
- also called specific reading disability
- common learning disability with children
- can be from posterior cerebral artery stroke
Patesthesia
- an abnormal sensation such as tingling, tickling, pricking, numbness or burning of a person’s skin
- can be symptom of thalamic syndrome due to posterior cerebral artery stroke
Athetosis
- slow, characterized by slow, involuntary, convoluted, writhing movements of the fingers, hands, toes, and feet
- in some cases arms, legs, neck and tongue
- can be symptom of thalamic syndrome post posterior cerebral artery stroke
Choreiform movements
- involuntary, forcible, rapid, jerky movements which are mostly manifestations of basal ganglia diseases (relatively small amplitude)
- can be from thalamic syndrome from posterior cerebral artery
Carotid Arteriogram
- arteriogram of the R carotid artery showing a severe narrowing (Stenosis) of the internal carotid artery just past the carotid fork
- there is enlargement of the artery after the stenosis
Basilar Artery Stroke Impairments
- brainstem
- coma
- quadriplegia
- “locked in” syndrome
- bilateral cerebellar ataxia
- thalamic pain syndrome
- diplopia or other visual field deficits including blindness
Locked-in syndrome
- can be from basilar artery stroke
- pure motor
- can’t move but they might be able to move their eyes and possibly communicate through the movement of their eyes
- intact consciousness
Vertebral Artery Stroke Impairments
- ataxia
- vertigo
- nausea
- vomitting
- nystagmus
- impaired pain and temperature sensation in ipsilateral face
- Horner’s syndrome (sympathetic dysfunction causing ptosis)
- dysphagia
- sensory impairment in contralateral arm, trunk, and leg
Vertebral Artery Test
- rotating away from side that testing, and extending of cervical vertebra
- look for pupil to dilate, for dizziness of individual
- can also check for nystagmus
Muscle Fiber type I
- slow, oxidative
- motor unit is slow
Muscle fiber type IIA
- fast, oxidative glycolytic
- motor unit is fast, fatigue-resistant
Muscle fiber type IIB
- fast, glycolytic
- motor unit fast, fatigable
Slow oxidative muscle fiber info (SO, Type I)
- motor units: many
- muscle fibers: few
- axon diameter: small
- tetanic tension: low
- fatigability: low
- speed of contraction: slow
- muscle fiber diameter: small
- capillarization: rich
- mitochondria: many
- ATPase: low
- oxidative enzymes: high
FF Motor Unit/FG Muscle Fiber Info (Type IIB)
- motor units: few
- muscle fibers: many
- axon diameter: large
- tetanic tension: high
- speed of contraction: fast
- muscle diameter: large
- capillarization: poor
- mitochondria: few
- ATPase: high
- Oxidative enzymes: low
Henneman Principle
- there exist an order to motor unit recruitment when GRADUAL CONTROL OF TENSION is important
- small motor units are recruited 1st and larger last
- large motor units are de-recruited 1st and small de-recruited last
- *THIS ORDER IS VIOLATED WHEN ONE IS PERFORMING BALLISTIC OR RELATIVELY FAST MOVEMENTS
Henneman Principle slope
- shows the control of speed of muscle force generation (graded)
Tactile Sensation
- identify pattern of sensory loss
- glove-like or sock-like loss = cortical lesion
- cortical lesion
Scapula Subluxation
- common occurrence after stroke
- humerus subluxes inferiorly out of glenoid fossa
- due to weakness or spasticity
- weight of humerus causes upward rotation of inferior angle of scapula
- abnormal position of scapula
- flaccid or low tone or weak muscles at shoulder and trunk lead to altered alignment of scapula and humerus
- dynamic stabilizers not present
- reliance on static stabilizers which overstretch due to weight of arm in dependent position
- inferior subluxation is most common
- assume due to low tone, but also hypertonicity pullin scap up that may not even be related to RCM
- best to position sidelying or with table/armrest under
Impairment if have an optic nerve lesion
- blind in one eye
Impairment if have an optic chiasm lesion
- Bilateral temporal field deficit
- i.e. blind in the outside/lateral of both eyes
Impairment if have an optic tract, optic radiations, and/or occipital lobe lesion
- L homonymous hemianopsia
- cannot see the L half of the visual field for BOTH eyes
Temporal lobe lesion eye impairment
- L upper quadrant homonymous hemianopsia
- Cannot see the upper left 1/4 in BOTH eyes
Parietal lobe lesion visual impairments
- L lower quadrant homonymous hemianopsia
- cannot see in the lower left 1/4 of visual field in BOTH eyes
occipital lobe lesion visual impairments
- homonymous hemianopsia
Optic Nerve Testing
- usually test with glasses on
- screen both eyes at the same time
- if deficit noted, test each individual eye
- know the optic nerve pathway (optic nerve, chiasm, tract, radiation)
Test 1 for Optic Nerve
- determine peripheral vision “edges”
- find the visual deficit in which quadrant
Test 2 optic nerve test
- which finger moving in each quadrant
Test 2/3?
- number of fingers held up in each quadrant
TBI cause
- caused by a bump, blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain
- altered consciousness (no matter how brief)
CHI of TBI
- closed head injury
- no skull fracture or laceration of the brain
- coup-countercoup
OHI of TBI
- Open head injury
- meninges have been breached, brain is exposed
Coup-countercoup
- coup: primary injury at impact in one direction from blow
- countercoup: secondary injury on the opposite side from bounce back/counteraction of forces
TBI prevelance
- 1.7 million TBIs occur either as an isolated injury or along with other injuries each year
- about 75% of TBIs that occur each year are concussions or mild TBI
- TBI is a contributing factor to about 1/3 (30.5%) of all injury-related deaths
TBIs by AGE
- 3 large peaks in lifetime of TBI
- children 0-4 years
- older adolescents 15-19
- adults afed >65 years
- *adults 75+ have highest rates of TBI-related hospitalization and death
TBI by GENDER
- in every age group, TBI rates are higher for males as compared to females
Costs of TBI
- direct medical costs and indirect costs such as lost productivity totaled an estimated $76.6 billion in the USA in 2000
TBI causes
- MVA >60% (auto 70%, pedestrian 5%, motocycle 25%)
- other <40%
TBI Prevention
- risk of brain injury in hospitalized motorcyclists is 2X for un-helmed vs. helmeted motorcyclists
- acute care costs for unhelmeted drivers are 3X cost
- in Cali, first year’s implementation of 1992 helmet law resulted in 37.5% DECREASE in statewide crash fatalities
- 140,000 head injuries per year are attributed to children and adolescents in bicycle accidents (estimated 74-85% mod-severe TBIS are prevented by bike helmets)
- 14% decrease in fatality for front passangers wearing seat belts
General Risk Factors of TBI
- young (avg TBI = 29 yo)
- male
- risk taking behaviors
- low income, urban
- substance abuse (50% hospitaliations for TBI associated with alc)
- availability of firearm
- previous TBI (sports-related concussions)
- older age (more susceptible to tearing of blood vessels, declines in cerebrovascular circulation)
Skull Fractures
- 24% of all patients admitted for CNS trauma sustained a skull fracture
- 38% of fractures were open
- 10% were depressed (<3 mm)
Location of Skull fractures in order most to least common
- frontal
- basilar
- parietal
- occipital
- temporal
Extracranial Injuries with TBI
- 82% at admission had one or more extra-cranial injury with TBI
- most common: head laceration (61%)
- facial fractures 13%
- hemo/pneumothorax 9%
- rib fx/long contusion 10%
- spleen 4%
- liver or bowel 11%
- genitourinary 3%
- UE fracture 14%
- LE fracture 19%
- pelvic fracture 4%
- hip fracture 2%
- other laceration 20%
Scapula Subluxation
- common occurrence after stroke
- humerus subluxes inferiorly out of glenoid fossa
- due to weakness or spasticity
- weight of humerus causes upward rotation of inferior angle of scapula
- abnormal position of scapula
- flaccid or low tone or weak muscles at shoulder and trunk lead to altered alignment of scapula and humerus
- dynamic stabilizers not present
- reliance on static stabilizers which overstretch due to weight of arm in dependent position
- inferior subluxation is most common
- assume due to low tone, but also hypertonicity pullin scap up that may not even be related to RCM
- best to position sidelying or with table/armrest under
Impairment if have an optic nerve lesion
- blind in one eye
Impairment if have an optic chiasm lesion
- Bilateral temporal field deficit
- i.e. blind in the outside/lateral of both eyes
Impairment if have an optic tract, optic radiations, and/or occipital lobe lesion
- L homonymous hemianopsia
- cannot see the L half of the visual field for BOTH eyes
Temporal lobe lesion eye impairment
- L upper quadrant homonymous hemianopsia
- Cannot see the upper left 1/4 in BOTH eyes
Parietal lobe lesion visual impairments
- L lower quadrant homonymous hemianopsia
- cannot see in the lower left 1/4 of visual field in BOTH eyes
occipital lobe lesion visual impairments
- homonymous hemianopsia
Optic Nerve Testing
- usually test with glasses on
- screen both eyes at the same time
- if deficit noted, test each individual eye
- know the optic nerve pathway (optic nerve, chiasm, tract, radiation)
Test 1 for Optic Nerve
- determine peripheral vision “edges”
- find the visual deficit in which quadrant
Test 2 optic nerve test
- which finger moving in each quadrant
Test 2/3?
- number of fingers held up in each quadrant
TBI cause
- caused by a bump, blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain
- altered consciousness (no matter how brief)
CHI of TBI
- closed head injury
- no skull fracture or laceration of the brain
- coup-countercoup
OHI of TBI
- Open head injury
- meninges have been breached, brain is exposed
Coup-countercoup
- coup: primary injury at impact in one direction from blow
- countercoup: secondary injury on the opposite side from bounce back/counteraction of forces
TBI prevelance
- 1.7 million TBIs occur either as an isolated injury or along with other injuries each year
- about 75% of TBIs that occur each year are concussions or mild TBI
- TBI is a contributing factor to about 1/3 (30.5%) of all injury-related deaths
TBIs by AGE
- 3 large peaks in lifetime of TBI
- children 0-4 years
- older adolescents 15-19
- adults afed >65 years
- *adults 75+ have highest rates of TBI-related hospitalization and death
TBI by GENDER
- in every age group, TBI rates are higher for males as compared to females
Costs of TBI
- direct medical costs and indirect costs such as lost productivity totaled an estimated $76.6 billion in the USA in 2000
TBI causes
- MVA >60% (auto 70%, pedestrian 5%, motocycle 25%)
- other <40%
TBI Prevention
- risk of brain injury in hospitalized motorcyclists is 2X for un-helmed vs. helmeted motorcyclists
- acute care costs for unhelmeted drivers are 3X cost
- in Cali, first year’s implementation of 1992 helmet law resulted in 37.5% DECREASE in statewide crash fatalities
- 140,000 head injuries per year are attributed to children and adolescents in bicycle accidents (estimated 74-85% mod-severe TBIS are prevented by bike helmets)
- 14% decrease in fatality for front passangers wearing seat belts
General Risk Factors of TBI
- young (avg TBI = 29 yo)
- male
- risk taking behaviors
- low income, urban
- substance abuse (50% hospitaliations for TBI associated with alc)
- availability of firearm
- previous TBI (sports-related concussions)
- older age (more susceptible to tearing of blood vessels, declines in cerebrovascular circulation)
Skull Fractures
- 24% of all patients admitted for CNS trauma sustained a skull fracture
- 38% of fractures were open
- 10% were depressed (<3 mm)
Location of Skull fractures in order most to least common
- frontal
- basilar
- parietal
- occipital
- temporal
Extracranial Injuries with TBI
- 82% at admission had one or more extra-cranial injury with TBI
- most common: head laceration (61%)
- facial fractures 13%
- hemo/pneumothorax 9%
- rib fx/long contusion 10%
- spleen 4%
- liver or bowel 11%
- genitourinary 3%
- UE fracture 14%
- LE fracture 19%
- pelvic fracture 4%
- hip fracture 2%
- other laceration 20%
Primary vs. secondary TBI
- primary: direct injury to the brain (i.e. impact, missile, shearing)
- secondary: damage after the traumatic event caused by brain hypoxia (lack of oxygen), edema, herniation, hematoma, ischemia
Focal vs. Diffuse TBI
- focal: localized trauma (small blow or tumor)
- diffuse: trauma over a large area (coup-countercoup)
Four Types of Hemorrhages
- epidural hematoma
- subdural hematoma
- subarachnoid hemorrhage
- intracerebral hematoma
Epidural Hematoma
- in epidural space, between dura mater and skull
- acute bleeding
- common in temporal bone fracture
Subdural Hematoma
- beneath the dura
- laceration of cortical veins during sudden head deceleration
- a feature of shaken baby syndrome
- seen in children because of firm adherence of dura to the inner skull
Subarachnoid Hemorrhage
- poor prognosis if bleeding into ventricular system
Intra-cerebral Hematoma
- in brain parenchyma (neurons & glial cells)
- hematoma may enlarge during the first few days after injury
Concussion
- mild TBI
- alteration of consciousness and memory
- CT or MRI usually normal
- good prognosis
- cumulative effects of repeated concussion (can cause dimentia)
Post-concussion
- dizziness, disorientation, nausea, headache, fatigue
- decreased control of emotions and personality changes
- attention deficit