Amyotrophic Lateral Sclerosis Flashcards
What are possible epidemiolgies of ALS
- sporadic/idopathic
- familial
Genes that are related to ALS
- C9orf72: ALS-FTD
- superoxide dismutase 1 (SOD1)
- TAR DNA-binding protein 43 (TARDBP/TDP-43)
- FUSED IN SARCOMA (FUS)
Known risk factors for ALS
- disease causing mutations
- sex: M>F
- age
- family history
- clusters: west pacific ALS/PDC
ALS
Potential/investigated risk factors
- Trauma: physical or emotional
- certain occupation characteristics: electrical workers, farmers, industrial occupation
- diet: high fat intake, high glutamate, low fibers, low antioxidant intake
- lifestyle factors: cigarette smoking, alcohol intake, anthropometric measures
- neurotoxicant exposure: lead, mercury, pesticide
- vigorous physical activity: heavy manual labor (corelation)
what is the pathophysiology
ALS
- progressive degeneration of motor neurons in spinal cord (LMN), brainstem (mixed), motor cortex (UMN)
- multisystem disease
- possible damage to NM junction where muscle sends “bad” signal
What does ALS affect as a multisystem disease
- autonomic nervous system (very common)
- basal ganglion
- cerebellum
- frontotemporal area of the cortex: executive function and memory
- oculomotor system: usually spared but can be affected
- sensory system: can be impaired as it progresses
Structures involved with ALS vs usually spared structues
- UMNs in cortex, lateral corticospinal tract
- CN: V, VII, IX, X, XII Affected
Spared
- CN: III, IV, VI: usually spared (eyes)
- onufroxicz nucleus in spinal cord usually spared: found in S1-S4 = spared bowel and bladder function
- sensation can be involved
Impairements: lower motor neuron
- weakness = cardinal sign/first sign
- focal weakness: 1 body part at first
- asymmetrical at first
- progress within a region
- UE weakness
- LE weakness
- cervical weakness
- fasciculations/cramping
Impairments: upper motor neurons
ALS
- spasticity
- hyperreflexia
- weakness
- clonus
- babinski
- usually there is a combination of UMNs and LMN => as th disease progresses UMNs become less evident due to decreased muscle fibers
Recovery of motor/neuronal function
with ALS
- collateral sprouting can occur
- good compensation until about 50% of original motor unit is lost
- EMG finding: large action potential where collatertal sprouting has occured
impairments: bulbar signs
- corticomotorneuronal (bulbar tracts)
- dysarthria: difficulty with forming words
- dysphagia: difficulty swalloing
- sialorrhea: excessive drooling
- pseudobulbar affect: not able to control emotions/inappropriate emotions
ALS
Impairments: respiratory
- decreased vital capacity
- fatigue: from muscle weakness and chronic loss of O2
- dyspnea on exertion
- orthopnea: difficulty breathing while lying down due to difficulty moving diaphragm
- daytime somnolence: decreased O2 and sleep distrubances
- headaches
Other impairments with ALS
less common but can happen
- cognitive: frontotemporal dementia
- sensory loss
- opthalmoplegia: weakness of eye function
ALS
how is ALS diagnosed
- mainly based on clinical findings
- may recieve another diagnosis at first
- LMN signs clinical or electrophysiological
- UMN signs
- progression
- absence of other disease: dx of exclusion
ALS
define clinically definite ALS
- LMN + UMNs 3 regions (bulbar +2 or 3 spinal)
ALS
Define clinically probable ALS
- LMNs + UMNs 2 regions here UMN is rostral to LMN signs
- LMN + UMNs 1 region or UMN 1 region and EMG evidence > regions
ALS
define clinically possible ALS
- LMN + UMN 1 region LMN is rostral to UMN
- UMN > 2 regions
Prognosis
- diagnosis at age younger than 35-40 has best prognosis (more than 5 year survival rate)
- limb onset has better prognosis than bulbar onset (problems with sallowing and speach)
- less severe involvement, plus no dyspnea at onset = better prognosis
Symptom management
ALS
- dysphagia: thickened liquid
- respiratory symptoms: pneumonia risk/coughing
- advanced directives: want to know in case they are with you and something happens
- sialorrhea: positioning and wipe mouth
- dysarthria: letter board
- depression and anxiety: losing respirtory function can cause anxiety
- muscle cramps, spasticity, fasciulations: PTs can treat
- pain: STM
Rehabiliation with ALS
can stage ALS into stages:
- early: prevent any secondary impairements and decrease the loss of function
- middle/late: preserve function
- disabilities increase over stages
- focus on prevention and restoration to compensation and preventions
exercise and ALS
- exercise in early restorative may help to slow disease progression and maintain function - secondary prevention
- monitor: fatigue and overwork weakness
overuse weakness with ALS
- patients with ALS can and should participate in strengthening exercises esp. in early stages
- no overuse weakness in MMT >3/5
- can use resistance
- avoid heavy eccentric exercise (fatigues quicker)
- still need to consider overwork fatigue
tertiary prevention with ALS
as disease progresses, focus on remediation of secondary pathology
- pressure ulcers
- edema
- atelectasis/pneumonia
- adhesive capsulitis
Compensatory interventions for ALS
- adapting activities: mobility and ADLs
- adapting environment: home, work
stages of ALS
stage: early
evaluation findings
- few/minimal impairments
- no/minimal activity limitations
- no participation restricitions
Stages of ALS
early stage: Procedural intervention strategies
- preventive
- restorative
- +/- compensatory
Stages of ALS
Stage: middle stage
evaluation findings
- increasing number/severity of impairments
- minimal/moderate activity limitations
- minimal/moderate participation limitations
Stages of ALS
middle stage procedural intervention strategies
- compensatory
- preventive
- +/- restorative
Stages of ALS
late stage
evaluation findings
- numerous/severe impairments
- severe activity limitations
- severe participation limitations
stages of ALS
late stage procedural intervention strategies
- compensatory
- preventive
- +/- restorative
other interventions and physical therpay roles in treatment of ALS
- patient/family/caregiver education and training
- psychological support
- referral to other health-care professionals
Cervical weakness problem
- hardest to fix
- can sometimes wear a collar
