Motor Neuron Diseases Flashcards
What is the most common adult onset motor neuron disease?
ALS
Does ALS affect UMN or LMN?
BOTH - it affects both UMN and LMN
Who is most often affected by ALS? Age of onset?
- White males and non-hispanics
- Typical age of onset is 55-75
What is the initial presentation of ALS?
- Asymmetrical, focal, distal weakness of one limb
* *Most commonly the UE > LE > bulbar
What does the progression of ALS look like?
It has a “contiguous progression” meaning it spreads to anatomically adjacent regions
**RUE»_space; LUE; RLE»_space; LLE
What is the clinical presentation of ALS?
- UMN signs (spasticity, clonus, hyper reflexia, and pathological reflexes)
- LMN signs (muscle weakness, muscle atrophy, fasciculations, hypo reflexia, hypotonicity)
- Other symptoms: sialorrhea, dysarthria, dysphagia, pseudobulbar affect, chronic fatigue, difficulties breathing, urinary changes
What functions and motor neurons are typically NOT affected by ALS
- Sensory
- Bowel and bladder
- Cognition
- Sexual function
- Cardiovascular
- Oculomotor
What is the life expectancy of ALS?
Average is 3 years from onset
**20% survive 5 years, 10% survive 10 years, and 5% survive 20 years
Better vs worse prognostic factors for ALS?
- Better = younger onset and having primary lateral sclerosis or spinal muscle atrophy vs classic ALS
- Worse = initial symptoms involving the bulbar muscles or respiratory system
What is the cause of ALS?
UNKNOWN, but it is associated with several genetic mutations
**90% is sporadic and 10% is hereditary, but no difference in clinical presentation
What criteria is used to Dx ALS?
- Presence of UMN signs, LMNS, and spread of sx within a region or to other regions
- Absence of other disease processes - electrodiagnostic testing
What do you expect to see on electrodiagnostic testing with ALS?
- EMG: Reduction in the number of motor units, fibrillations and fasciculations.
- Nerve conduction tests: Usually normal but might be slightly slowed
What medication is use to treat ALS? How does it work? Pros and cons?
Riluzole: It decreases the release of glutamate.
- It increases life expectancy by 2-9 months - It’s very expensive
Exercise intensity recommendations for people with ALS
- High intensity exercise is CONTRAINDICATED in all stages of ALS
- Moderate intensity exercise may be beneficial in EARLY stages only
Use of AD and DME for persons with ALS
- Manual w/c is often not recommended/ordered due to progressive nature of disease
- Power w/c is order early and can be adapted
What causes polio?
Virus poliomyelitis that causes inflammation to the meninges and anterior horn cell with loss of spinal and bulbar motor neurons
What is the clinical presentation of polio?
Asymmetrical, flaccid paralysis, usually LE > UE
What is post polio syndrome?
New onset of symptoms occurring 15-40 years post infection
What are symptoms of post polio syndrome?
- Fatigue
- New respiratory difficulties
- Cold intolerance
- Weakness
- Joint and muscle pain
- Decreased endurance
What is the progression like in post polio syndrome?
Slow and steady progression: 1-2% increase in weakness per year
Why do they think post polio syndrome occurs?
Failure of the oversized motor units that developed due to collateral sprouting
What factors increase the likelihood of developing post polio syndrome?
- > 10 years old
- Requiring hospitalization for the illness
- Paralytic involvement of all four limbs
- Vent dependent
- Rapid return of function following extensive involvement
Physical therapy management of persons with post polio syndrome (interventions, focus of treatment, etc)
- Energy conservation technique, submaximal short duration strength training, cardiovascular conditioning, stretching, decrease stress on joints, respiratory techniques,
- Education: Fatigue and over work weakness are common, need to educate on submax exercise and energy conservation
How many people who had polio will develop post polio syndrome?
25-40%
Does GBS affect UMN or LMN?
LMN, CNS is unaffected.
What is the mechanism of GBS?
- Autoimmune disorder of the PNS
- Inflammatory process affects the Schwann cells causing de-myelination of the axon
- Axon can remain intact or in some cases axonal damage occurs
What causes GBS?
- Following non specific viral syndrome (IE mild upper respiratiory infection)
- Also associated with viral infections, Campylobacter jejuni bacterial infection, vaccinations or recent surgery, lymphoma, systemic lupus, AIDS
Who is most affected by GBS?
- Men > women
- Ages 30-50 yr old
What is the clinical presentation of GBS?
- Progressive symmetrical weakness of the limbs and face; legs to arm, to face
- Paresthesias in the hands and feet in a glove and stocking distribution
- Back pain
- Diminished/absent DTR
- CN are affected in ~50% of all cases
How fast/slow does GBS progress?
Onset to peak disability ranges from hours to week
What type of disease is GBS
Autoimmune disorder of the PNS
Medical management of GBS- what is recommended? What is NOT recommended?
- ) (IVIg) intravenous immunoglobulin therapy is recommended over plasma exchange therapy because its easier to administer and is associated with fewer complications.
- ) Corticosteriods have not shown to be effective - actually delays recovery
PT/exercise considerations for patients with GBS?
- Watch for overwork weakness due to DOMS 1-5 days post activity and reduction in maximum force production that gradually recovers
- Train fast twitch muscle contractions
- Monitor vitals during aerobic exercise due to autonomic dysfunction
What is the hallmark sign of Myasthenia Gravis?
- Fluctuating fatigue and strength.
- Weakness/fatigue increase during activity and improves with rest
- *Environmental factors can also affect symptoms
What structures does Myasthenia Gravis affect?
- Oculomotor
- Facial
- Mastication
- Speech and swallowing muscles
What is the medical management for myasthenia gravis?
Corticosteroids or immunosuppressants
What are the rehab implications for people with myasthenia gravis?
- Energy conservation
- Risk for falls with decreased bone density
Who does myasthenia gravis usually affect?
Younger females and older males
What are some trophic changes that can occur with peripheral neuropathy?
Shiny skin and brittle nails
What are some autonomic symptoms that can occur with peripheral neuropathy?
- Abnormal sweating
- Changes in BP regulation (OH)
- Abnormal HR
- Bowel and bladder changes
Peripheral nerve anatomy
- Epineurium - entire nerve
- Perineurium - around fasciculations
- Endoneurium - around axons
Seddon Classification
Class I - neurapraxia
Class II - axonotmesis
Class III - neurotmesis
Sunderland Classificatrion
Grade I - neurapraxia, complete/fast recovery
Grade II - axonotmesis, full recovery
Grade III - disruption of axon/endoneruium, variable recovery
Grade IV - disruption of axon, endoneurium and perineurium with no recovery, surgery required
Grade V - nerve disection, surgery
Charcot-Marie-Tooth Disease
- Genetic condition that affects motor/sensory nerves
- Associated with leg weakness and foot deformities
- Progressive, no treatment available
