Spinal muscular atrophy

Question 1

inheritance pattern?

Answer 1

autosomal recessive

Question 2

pathology?

Answer 2

degeneration of anterior horn cells, causes progressive loss of LMN –> progressive muscular weakness

Question 3

O/E?

Answer 3

LMN signs

• reduced tone & power
• fasciculations
• reduced muscle bulk
• reduced or absent reflexes

Question 4

types?

Answer 4

SMA type 1–> 4

• type 1: most severe (death by 18 months)
• type 2: most common
  
  • onset within first 18 months
  • most never walk but survive into adulthood
• type 4: onset in 20s

Question 5

Ix?

Answer 5

EMG, genetic testing

Question 6

Mx?

Answer 6

MDT approach