Amyotrophic Lateral Sclerosis Flashcards
What is ALS? Pathophysiology?
“Creeping Paralysis”
- Progressive degeneration & loss of motor neurons (MN) in spinal cord & brainstem (LMN) and motor cortex (UMN)
- 60% of individuals die within 3 years of onset - usually of respiratory failure
- SYNDROME rather than single disease
Who is more at risk for aquiring ALS?
a) 45 YO female
b) 22 YO female
c) 57 YO male
d) 35 YO male
C) 57 YO male
- more common in males
- risk peaks between 50-75 YO, median age of onset is 55 YO
What are the risks of ALS?
- Age (50-75 YO)
- Family history
What are potential causes of ALS?
- oxidative stress
- mitochondrial dysfunction
- defective glutamate metabolism
- protein aggregation in cell body and proximal axon
- impaired axonal transport
- dysregulated endosomal trafficking
What is impacted early on in ALS?
bad wording but couldnt think of anything else :(
Motor neurons
- affected earliest & most severely
What are some diagnostic tests for ALS?
No specific diagnostic test for ALS, diagnosis reached after observing clinical signs associated with ALS and ruling out other pathologies with tests/imaging
* disease progression MUST be seen for diagnosis of ALS (other mimic syndromes dont progress as fast
What are the EL Escorial Criteria?
- Evidence of LMN degeneration by clinical/elecrophysiological exam
- Evidence of UMN degeneration by clinical exam
- Progressive spread of symptoms/signs within a region or to other regions
What is the general clinical course of ALS?
- gradual, over months
- asymmetrical
- first symptoms often UMN & LMN signs in 1 limb that spreads
- initial weakness usually in isolated muscles - distally
- normal sensation
- normal oculomotor, bowel & bladder functions
What are the UMN and LMN symptoms that occur in the beginning?
UMN: spasticity, hyperreflexia, clonus
LMN: atrophy, weakness, fasciculations
What are the types of onset that could occur?
- Bulbar- onset (20-30% of pts)
- cervical onset (AKA limb onset - 65-80%)
- lumbar onset (AKA limb onset - 65-80%)
- Respiratory onset (5% of pts)
What would someone with Bulbar onset present with?
- Dysarthria &/or dysphagia
- LMN: bulbar palsy -> weakness of facial muscles & tongue, fasciculation (brief small contractions) of tongue, decrease palatal mov’t & atrophy
- UMN: pseudobulbar palsy - brisk jaw jerk, emotional lability (pathological laughing or crying), tongue spasticity
- more frequent in women and in late-onset disease
What would someone with cervical onset present with?
bilateral or unilateral UE symptoms
- proximal weakness (e.g., shoulder abduction)
- distal weakness (e.g., pincer grip)
- UMN (hyperreflexia) &/or LMN signs (e.g., atrophy, fasciculations)
What would someone with Lumbar onset present with?
- LMN signs in legs (e.g., foot drop, proximal weakness manifested as difficulty ascending/descending stairs)
- UMN signs often follow (e.g., hyperreflexia, clonus)
- Degeneration of ant horn cells in lumbar enlargement
What would someone with Respiratory onset present with?
- Dyspnea - attacks can cause anxiety
- respiratory muscle weakness
- chronic nocturnal hypoventilation
➜ leads to disordered sleep & daytime fatigue
➜ can occur months/years before repsiratory failure
➜ significantly decreases quality of life - thick mucous secretions from decrease fluid intake, & decrease coughing pressure
- pneumonia common
What symptoms might an individual present with regardless of disease phenotype?
- Dysphagia
- Dysarthria
- Respiratory muscle weakness (accessory muscles for breathing, paradoxic breathing)
- pain (MSK pain in later stages due to atrophy & altered tone around joints, muscle contractures & joint stiffness)
- cognitive impairment
- Affect social life
- quality of life -> pts friends, family, caregivers show greater depression & anxiety than general population
What is the typical terminal stage?
> 60% die within 3 years of diagnosis
What are some favourable prognostic indicators?
- age <50 years
- lower limb onset
- long interval from first symptom to diagnosis
- hyperlipidemia
- attendence at MTC clinic
- pure UMN/LMN conditions
what are some poor prognostic indicators?
- age >65 years
- bulbar onset
- respiratory onset
- short interval from first symptom to diagnosis
- malnutrition
- impaired executive function
- low cardiovascular risk (a favourable lipid profile)
- rapidly declining Revised ALS Functional Rating scale score
- forced vital capacity <50%
what is the medical management of ALS?
Riluzole - inhibitis presynaptic release of glutamate (decrease toxic effect of excessive glutamate) & increases lifespan by a median of 11-14 months
Edaravone - antioxidant & free radical scavengar
What would PT management include?
*Rehabilitation in Reverse - standyby assistance -> moderate/max assistance -> mechanical lift
- education
- mobility training
- cardioresp PT
- ROM
- strengthening
- prevention of secondary complications (prevent contractures, maintain respiratory health)
- reduction of pain, spasticity
What would you include in your assessment?
- MMT or hand-held dynamometry
- Forced vital capacity (FVC)
- ALS functional rating scale
these are important for tracking disease progression
What is the ALS functional rating scale?
10-item ordinal rating scale
0= unable to attempt, 4= normal function
Instrument for evaluating the functional status of patients with Amyotrophic Lateral Sclerosis.
What could you educate the pt on?
safe mobility, fall prevention, energy conservation, positioning/pressure relief, ROM exercises to prevent contractures & MSK pain, prevenion of pulmonary complications, resources, disease progression - what to expect
Is it safe for pts with ALS to exercise?
Yes in early stages when pts have sufficient strength, respiratory function & endurance to exercise without excessive fatigue
Research now says that it is safe if tolerable and carefully supervised
What are some pulmonary complications that can occur?
in the early stages pulmonary impairment can go unnoticed becuase of limb weakness - pts tend to not exert themselves & reespiratory symptoms like dyspnea might not be experienced
- dysphagia
- poor secretion removal
- respiratory failure -> Non-invasive positive pressure ventilation (NIPPV) preferred method of ventilatory support
