motor neuron disease Flashcards
(91 cards)
1
Q
motor neuron disease
A
a neurodegenerative disease characterized by progressive muscular paralysis reflecting degeneration of motor neurons
2
Q
where does degeneration of motor neurons happen
A
- primary motor cortex
- corticospinal tracts
- brainstem
- spinal cord
3
Q
heterogeneous or homogeneous
A
heterogeneous
4
Q
hallmarks of MND
A
- rapidly progressive disorder of the nervous system
- does not affect sensory or autonomic systems
5
Q
life expectancy from first symptom
A
4-5 years
6
Q
MND causes degeneration in the UMN or LMN
A
both
7
Q
motor neuron degeneration results in what symptom and dysarthria type
A
- muscle weakness
- flaccid or spastic dysarthria
8
Q
how does spasticity cause muscle weakness
A
- reduced mobility leading to muscle atrophy from disuse
- impaired coordination, reducing overall strength and control
- fatigue
9
Q
terms synonymous with MND
A
- amyotrophic lateral sclerosis (ALS)
- Lou Gehrig’s disease
10
Q
typical onset
A
- as early as 20s
- usually early 60s
11
Q
do women or men have a higher risk
A
women
12
Q
prognosis
A
- no cure/remission
- no effective drug treatment
- 50% live < 3 years post-diagnosis
- 20% live 5+ years
13
Q
peak incidence between ages ?
A
55 - 75 years
14
Q
types of MND and %
A
- sporadic (90%)
- inherited (10-15%)
15
Q
inherited familial cause
A
- genetic link
- 30+ genes identified
16
Q
how to differentiate MND from PD/MS
A
never sensory changes in MND
17
Q
MND general symptoms
A
- weakness
- slurred speech
- dysarthria
- muscle cramps and twitches
- weight loss
- emotional lability
- cognitive changes
18
Q
emotional lability suggests ?
A
UMN involvement
19
Q
which CN are resistant to degeneration
A
- CN III, IV, VI motor
- eye movements
20
Q
emotional lability
A
- inability to control emotions
- crying/laughing but not sure why
21
Q
fronto-temporal dementia (FTD) in ?% of MND
A
5-15%
22
Q
subtypes of MND
A
- amyotrophic lateral sclerosis (ALS)
- progressive bulbar disease (PBP)
- progressive muscular atrophy (PMA)
- primary lateral sclerosis (PLS)
- Kennedy’s disease
23
Q
amyotrophic lateral sclerosis (ALS)
A
- UMN + LMN
- weakness and wasting in the limbs
- life expectancy from symptom onset: 2-5 year
24
Q
progressive bulbar disease (PBP)
A
- affects 1/4 of people diagnosed with MND
- UMN + LMN
- slurred speech and dysphagia
- life expectancy from symptom onset: 6 months-3 years
25
progressive muscular atrophy (PMA)
- rare
- LMN only
- life expectancy: 5+ years
26
primary lateral sclerosis (PLS)
- rare
- UMN only
- mainly weakness in lower limbs
- some clumsiness with hands and/or slurred speech
- life expectancy: normal (unless it develops into ALS)
27
Kennedy's disease
- slowly progressive disorder of motor neurons
- genetic mutation
- rare form of muscular atrophy causing weakness
- only affects men (women can be a carrier)
- life expectancy: normal
28
? features are intrinsic to some subtypes of MND
cognitive
29
cognition changes in MND are associated with ?
- aggressive disease
- genetic mutation
- non-compliance
- caregiver burden
30
up to ?% of MND patients develop a cognitive impairment
50%
31
cognitive screening tests
- ALS Brief Cognitive Assessment
- ALS Cognitive Behavioral Screen
32
after MND diagnosis, patients should be screened for ?
cognitive and behavioral changes
33
cognitive changes
- executive function
- fluency
- language
- social cognition
34
behavioral changes
- apathy
- loss of sympathy
35
?% have concomital behavioral-variant FTD
13%
36
theories for causes of MND
- genetic
- traumatic
- toxic
- viral
- excitotoxicity
- oxidative stress
37
excitotoxicity
toxins interacting with glutamate receptors resulting in cellular calcium overload
38
oxidative stress
motor neuron damage from a cascade of reactions initiated
39
MND initial presentation
- stumbling
- foot drop
- loss of dexterity (increased conscious effort needed)
- weakened grip
- cramps
- voice changes
- fasciculations
- swallowing problems
40
average delay from onset of symptoms to diagnosis is ?
14 months (1/3 expected survival)
41
UMN symptoms
muscle weakness, stiffness, slowness of movement, tightness, spasticity
42
UMN features
- increased limb tone
- muscular weakness
- brisk tendon reflexes
- extensor plantar responses
43
LMN symptoms
muscle weakness, atrophy, cramping, and twitching
44
LMN features
- muscle wasting/atrophy
- fasciculations
- weakness with reduced or absent tendon reflexes
45
how to differentiate MND, spinal muscular atrophy (SMA), and Kennedy's disease
fasciculations only occur in MND
46
possible sites of onset for MND
- limb/spinal
- bulbar
- respiratory
47
which site of onset has the worst prognosis
bulbar
48
limb/spinal onset will almost always progress to ? site of onset
bulbar
49
limb/spinal onset
- most common (60-70%)
- asymmetrical early symptoms
- upper limb presentation more common
- cramps/fasciculations
- heaviness or stiffness of legs
- often reported/stumbling
50
respiratory onset
- least common
- respiratory failure due to loss of bulbar, cervical, and thoracic motor neurons
- inspiratory muscles preferentially affected
- decrease in lung vital capacity to 50%
- initial report of mild dyspnea on exertion, morning sleepiness, headaches
51
why does respiratory onset manifest as morning sleepiness and headaches
lack of oxygen (retaining CO2)
52
respiratory onset assessments
- pulmonary function (PFTs)
- spirometry
- arterial blood gas (ABGs)
53
respiratory stage (not onset) features
- typically in advanced disease
- shortness of breath on exertion
- daytime sleepiness
- fatigue
- headache
- orthopnea
- weak cough/sniff
- nighttime restlessness/sweating
54
SOBOE
shortness of breath on exertion
55
orthopnea
shortness of breath when lying down that's relieved by standing or sitting up
56
bulbar onset
- speech, swallowing, and OMA changes
- mostly bulbar as advanced stages not onset
- associated with: shorter survival, faster function decline, reduced QOL, increased support needs
57
symptoms of respiratory insufficiency in MND
- orthopnea
- SOBOE
- disturbed nighttime sleep
- excessive daytime sleepiness
- difficulty clearing secretions
- fatigue
- anorexia
- depression
- poor concetration/memory
- morning headaches
- nocturia
58
signs of respiratory insufficiency in MND
- increased respiratory rate
- use of accessory muscles
- paradoxical movement of abdomen
- decreased chest movements
- weak cough
- sweating
- tachycardia
- weight loss
- confusion
- papilloedema (rare)
59
nocturia
waking up more than once during the night because you have to pee
60
paradoxical movement of abdomen
chest wall or the abdominal wall moves in when taking a breath and moves out when exhaling
61
papilloedema
swelling of the optic discs due to intracranial hypertension
62
direct MND symptoms
- weakness/atrophy
- fasciculations
- spasticity
- dysarthria
- dysphagia
- dyspnea
- emotional lability
63
indirect MND symptoms
- psychological problems
- sleep disorders
- constipation
- drooling
- secretions
- pain (cramping)
- hypoventilation
64
are direct or indirect MND symptoms associated with a lower QOL
indirect
65
how to diagnose MND
- no one specific test, based on clinical findings
- Gold Coast Criteria (Shefner et al., 2020)
- El Escorial Criteria (1994)
66
Gold Coast Criteria
- newer set of simpler criteria for diagnosing MND
- presence of UMN and LMN dysfunction in 1+ body region
OR
- signs of LMN dysfunction in 2+ body regions
67
El Escorial Criteria
- established by WFN (World Federation of Neurology), updated in 2000
- mixed UMN and LMN damage in the absence of other causes
68
indirect MND diagnostic tests
- needle electromyography (EMG; monitor the electrical signals in 1 muscle and look for irregular activity)
- nerve conduction studies (look at efficiency)
- chest x-ray
- autoantibody screen
- thyroid function tests
- creatine kinase
- biochemical screen (look at genes for familial link)
- full blood count
69
diagnostic materials for bulbar signs or MND
- cranial nerve exam
- needle EMG (genioglossus, SCM, trapezius)
- clinical MRI of bulbar regions
- auditory perceptual ax of dysarthria
- frenchay dysarthria ax
- videofluoroscopy swallowing exam
- EAT-10
- 3oz swallow test
- voluntary cough
70
outcome measures/rating scale test
- ALSFRS (Amyotrophic Lateral Sclerosis Functional Rating Scale)
- areas relevant for SLTs: speech, salivation, swallowing
71
MND treatment
- MDT
- mostly symptomatic relief
- individualized alleviation of symptoms/complications
- rizuole
- based on excitotoxicity theory of MND pafthogenesis
72
riluzole
- MND treatment
- primary line of defense
- prolongs median survival from 11.8 months to 14.8 months
73
newer drug treatments for MND
- ellorarxine
- tofersen (SOD1 gene)
- edaravone
- nuedexta
74
SLT input
- speech/communication
- swallowing
- sialorrhea (drooling)
75
dysarthria/dysphagia signs in MND
- flaccid or spastic
- strangled voice quality (if spastic)
- vocal cord paresis
- soft palate involvement
- dysphagia for solids and liquids
- nasal regurgitation
- choking episodes
- weak cough/throat clearing
- drooling
- tongue fasciculations
76
dysarthria in MND is associated with....
low mood, withdrawal from activities, social isolation
77
LMN MND
- bulbar palsy
- flaccid dysarthria
- nasal speech
- nasal regurgitation
- absent jaw jerk
- reduced/absent gag reflex
- lingual atrophy/fasciculations
78
UMN MND
- pseudobulbar palsy
- spastic dysarthria
- emotional lability
- brisk jaw jerk
- hypersensitive gag reflex
- shrunken immobile tongue
79
which therapeutic approach to MND (and why)
- compensatory approach
- to optimize intelligibility
80
speech subsystems and typical impairments in MND
- respiration (poor respiratory support for speech short phrases)
- phonation (strained-strangled voice, low pitch, weak breathy voice, audible inspiration, low volume)
- articulation (imprecise consonants, distorted vowels, rate and range of articulators)
- prosody (monopitch, monoloud, reduced stress)
- resonance (hypernasality)
81
dysarthria management
- education
- compensation
- AAC
- voice/message banking
82
AAC considerations
- upper limb function
- literacy
- computer confidence
- cognition
- socially acceptable
- timing
- decline
- prognosis
83
types of AAC switches
- click
- air pad
- bulb
- puff
- foot
- eye blink
84
goal of dysphagia management for MND
- safe and efficient oral intake of food and fluids
- maximum independence
- emphasis on patient's wishes and QOL
85
swallow management in MND usually involves use of ? strategies (and why)
- compensatory
- active exercises simply cause fatigue
86
which recommendations can SLTs make
- education/written info
- volume control beaker
- compensatory strategies (chin down, double swallow)
- diet modification
- list of foods to avoid
- saliva management
- discussion with MDT re: long term nutritional management (i.e. PEG insertion)
- EMST
87
what is important to consider with PEG insertion
- site of onset
- respiratory onset requires a quicker PEG insertion because of limited respiration
88
tube feeding in MND
- should not be seen as crisis intervention when the patient is malnourished and dehydrated
- ideally at 5% weight loss and before respiratory involvement
- consider respiratory reserve
89
PEG does not mean ?
NPO (aim for some form of oral intake for QOL)
90
sialorrhea treatments in MND
- behavioral changes
- education
- anticholinergic meds
- botox
- radiation (fewer side effects but shorter duration than botox)
- portable suctioning devices
91
anticholinergic medication function
block the receptors that stimulate saliva production
