Spinal Muscular Atrophy Flashcards
Spinal muscular atrophy refers to neurogenic disorders whose underlying pathology affects what?
sensory and spinal interneurons and as a result anterior horn cells
SMA is an autosomal ______ disease
recessive
What are the 3 classes of SMA?
- Type I
- Type II
- Type III
What is SMA type I aka?
Werdnig-Hoffmann disease
How is a child diagnosed with SMA type I?
they are so weak that they have never learned to sit
When is SMA type I almost always noted?
within the first 3 months of life
What are the initial symptoms observe in SMA type I?
axial hypotonicity and difficulty feeding
Patietns with SMA type I have limited repiratory function, describe their general breathing pattern
Paradoxical, with the diaphragmatic muscles playing the primary role in ventilation
Approximately half of the children with infantile SMA do not survive beyond _ years of age
2
When does SMA type II initially present?
later in the first year of life when the child is noted to not pull to stand
What is a common sign in children with SMA type II?
Fasciculations of the tongue
What happens when children with SMA type II attempt to use their limbs?
fine tremors
What 2 muscle groups are most prone to contracture in SMA type II?
knee flexors and ankle plantarflexors
What is SMA type III aka?
Kugelberg-Welander Disease
When does SMA type III typically appear?
it varies anywhere from the toddler years into adulthood (may be considered type IV if this late)
