Oct4 M1,2-Pediatric Neuro SG

Question 1

how UMN inhibits excessive firing of LMNs

Answer 1

via interneurons

Question 2

LMNs are where in the body

Answer 2

• spinal cord

- brainstem

Question 3

why measure baby’s head circumference

Answer 3

• direct reflection of head and brain geowth to eval growth and dev
• deviation form normal = congenital, genetic or acquired problem

Question 4

mutations in spinal muscular atrophy

Answer 4

• SMN1 gene mutation is the main one (autosomal recessive dz for this gene) (deletion mutation of exon 7)
• SMN2 modulates the dz (we can have between 0 and 8 copies of it. if have SMA + 0-1 SMN2 = sever pheno, if 3-4-5 = partial compensation of SMN1 absence

Question 5

reflexes that are usually tested for

Answer 5

• biceps (tip of triangle)
• brachioradialis (base of triangle)
• triceps (tip of triangle)
• knee (patellar) reflex
• ankle (Achilles) reflex

Question 6

how to test for tone

Answer 6

in arms and legs

• check diff joints
• spasticity is velocity dep (sudden catch)
• rigidity = velocity indep
• flexion, extension, pronation, supination, wrist for arm
• wiggle leg and see if ankle wiggles for leg, etc.
• check for clonus (repeated muscle contractions of the ankle when move knee up)
• fasciculations = for one motor unit (1 UMN, 1 LMN, its muscle fibers) IS NOT related to tone*