share email twitter ⋅ join discord whatsapp(2ck)
Free 120  NBME 24  NBME 23  NBME 22  NBME 21  NBME 20  NBME 19  NBME 18  NBME 17  NBME 16  NBME 15  NBME 13 
introducing : the “predict me” score predictor NEW!
NBME 16 Answers

nbme16/Block 1/Question#48 (26.1 difficulty score)
A 12-year-old boy is brought to the physician ...
Abnormal myelin sheathsπŸ”,πŸ“Ί

Login to comment/vote.

Tutor box

Members from the Leaderboard offering 1-on-1 help: Want to be listed here? Email us!

submitted by daddyyikes(1),
unscramble the site ⋅ remove ads ⋅ become a member ($39/month)

it si htocrac reima ototh eadisse as it is ndteeriih adn with roaamlbn ymenil ehtah,s foto o,pdr mhmear eto ec.t

cheesetouch  fa18 p 508 +2  

submitted by aoa05(30),

A high stepping gate implies distal more than proximal weakness. Hammer toes are a finding in Charcot-Marie-Tooth (hereditary motor and sensory) neuropathies, most of which also feature demyelination of peripheral myelin sheaths. Slowing of nerve conduction velocities could have demonstrated the same thing less invasively.?

notyasupreme  Ask me why I thought this was Friedreich Ataxia and not CMT fml lol +  
shakakaka  Why did you think that it's FA? +1  

submitted by topgunber(42),

hardest part for me was differentiating absence of schwann cells vs abnormal myeling sheaths. Schwann cells come from neural crest cells so we would expect to see other neural crest migration issues in my opinion. CMT disease has motor and sensory issues because PMP-22 peripheral myelinating protein is mutated. leads to abnormal myelination of the peripheral nerves. foot drop from sensory degradation, muscle atrophy from motoneuron involvement (also peripherally myelinated)

topgunber  foot drop from motor degradation , high stepping gait from sensory degradation. also associated with hearing issues. +  
proteinbound123  I think it should be: high stepping gait from foot drop from motor degradation from CMT neuropathy that can cause motor (like this) or sensory abnormalities. +