Week 8 Motor Neuron Disorders Flashcards
what is post polio syndrome (PPS)
new, slowly progressive muscle weakness occurring in individuals with a confirmed history of acute poliomyelitis following a stable period of functioning Attacks LMN, anterior horn cells
background and etiology of PPS
estimated 1352 cases worldwide, and unknown. 22-68% of polio survivors will develop PPS. women more then men
how long after polio does PPS peak
30-34 years
what is the pathology of PPS
motor unit dysfunction because of overuse, MSK overuse and disuse, loss of motor units and normal aging, predisposition to motor neuron degeneration, virus reactivation, immune mediated syndrome, effect of growth hormone, and combined effects.
what is the presentation of PPS
new weakness and atrophy abnormal fatigue pain decreased function slow progression cold intolerance cognitive deficits sleep disturbances decreased mobility
what is the prognosis of PPS
not life threatening, progressive weakness, and compensatory strategies are learned.
what is amyotrophic lateral sclerosis (ALS)
the destruction of UMN and LMN bilaterally, may be asymmetric. degeneration of the anterior horn cells and descending corticobulbar and corticospinal tracts.
astrocytes do not pick up the glutamate which leads to excitotoxicity
what is the genetic mutation and gene for familiar ALS
SOD1 enzyme is not made
and the gene is autosomal dominant (Chromosome 21)
what is the UMN signs of ALS
hyperreflexia weakness pathologic reflexes babinski pseudo bulbar affect spasticity
what are the LMN signs of ALS
hypo reflex and Tonia, fasciculations, fibrillations and atrophy and weakness
with ALS, what do you need, UMN or LMN signs
both!
what is the presentation of ALS
characterized by the absence of sensory symptoms (only about 20% will have sensory changes).
cognition, extraoccular eye movements, ANS, bowel and bladder, sexual functions, sight, smell and hearing is usually intact. Pseudo-bulbar S and S
what are the pseudo-bulbar S and S of ALS
dysarthria, dysphagia and emotional changes
additionally signs and symptoms of ALS
Autonomic dysfunctions (not usually, only in 1/3), muscle weakness, respiratory impairments, pain, cognition is normal, but depression is common
is cognition affected by ALS
usually normal
what are the 4 proposed pathologies of ALS
- excitotoxicity and glutamate transport
- oxidative stress
- mitochondrial dysfunction
- protein aggregation
excitotoxicity and glutamate transport:
excitotoxicity and glutamate transport: the glutamate transporter is lost, so glutamate clearance is interfered with, and calcium influx, which triggers apoptotic pathways and motor death
oxidative stress
mutation in antioxidant enzyme SOD in 20% familial. leads to a buildup of oxidative stress
what is mitochondrial dysfunction
suggests SOD 1 damage, impaired calcium handling, and promotes activation of cell death pathways
what is protein aggregation
during an increased physiological or environmental stress, cells with normally hold mutant proteins (with toxins), and keep them in check. they are overloaded and impaired, so toxins make a mess
what are the 3 ALS2 related disorders
- infantile-onset ascending hereditary spastic paralysis (IAHSP)
- juvenile primary lateral sclerosis (JPLS)
- autosomal recessive juvenile ALS (JALS)
what is IAHSP
onset of spasticity with increased reflexes, and sustained clonus of lower limbs within the first two years of life. weakness and spasticity increases in the upper limbs by 7-8 years, and then in the second decade bound to a WC, and progresses to spastic tetraplegia and pseudo bulbar syndrome.
what is JPLS
loss of ability to walk during the second year of life, sings one UMN disease, WC bound, and loss of motor speed production
what is JALS
onset around 6.5 years old, spasticity of facial muscles, uncontrolled laughter, dysarthria, spastic gait, atrophy, bowel and bladder dysfunction and sensory disturbances.
what is the prognosis of ALS
death from respiratory failure, 50% live longer then 30 months, 20% live 5 years or more, less then 10% survive longer than 10 years.
what is pseudo bulbar palsy
bilateral dysfunction of corticobulbar innervation of brainstem uncle, a central or UMN lesion like a corticospinal lesion disrupting function of anterior horn cells.
pseudo bulbar palsy produces similar symptoms as
bulbar palsy
what are some symptoms of pseudo bulbar
no gag reflex, hard to articulate, and phonate, and disruption of emotion, and inappropriate responses.
what is progressive bulbar palsy (PBP)
motor neuron disease of the bulbar muscles, degenerative of motor neurons in the cerebral cortex, spinal cord, brainstem and pyramidal tracts
involves glossopharyngeal, vagus and hypoglossal cranial nerve.
onset of 50-70 years old.
common symptoms to ALS
what is primary lateral sclerosis (PLS)
rare sporadic disorder with progressive spasticity of spinal and bulbar onset. UMN (LMN S\stays intact). spasticity, and typically begins in the Les. slower than ALS,
approximately 45% of those with PLS will develop what kinds of symptoms, which progresses to ___
LMN symptoms, progress to ALS
what is progressive muscular atrophy (PMA)
sporadic degenerative disease, affecting anterior horn cells, no UMN signs. Rare, and onset around 57. distal limb weakness and muscle atrophy. bulbar symptoms develop. 5-6 month survival
what is spinal muscle atrophy (SMA)
genetic disorder (autosomal recessive, deletion of motor neuron-1 gene). the motor neurons with cell bodies in the spinal cord degenerate (anterior horn cells). 1 in 6000 births
what is the presentation of SMA
muscle weakness and atrophy, skeletal muscles affected, and severity goes by type, which impacts more of the ability to use your muscles. premature death
when doing a motor neuron disease evaluation, what are we looking for
time of onset, and initial presenting symptoms. Patterns of weakness and spasticity (Bilateral or unilateral), distal and proximal, and limb or bulbar predominant.
