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Old 10-05-2012
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Hammer and Otoscope The pathophysiologic mechanims behing Babinski Reflex?

Hi all
Could somebody pls explain why we get the babinski response in UMN and why not in LMN
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Old 10-06-2012
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In UMN lesion (anywhere above anterior horn nucleus) the cortical inhibition of reflex arc is lost which inhibits the extensor withdrawal response>> fanning of toes n extension of great toe>> Babinsky sign on eliciting plantar reflex

Well in LMN, the motor component of the reflex arc itself is lost so primarily Plantar reflex is absent(but there is nothing like negative Babinsky sign)
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Old 10-07-2012
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Question

Quote:
Originally Posted by Rookie View Post
In UMN lesion (anywhere above anterior horn nucleus) the cortical inhibition of reflex arc is lost which inhibits the extensor withdrawal response>> fanning of toes n extension of great toe>> Babinsky sign on eliciting plantar reflex

Well in LMN, the motor component of the reflex arc itself is lost so primarily Plantar reflex is absent(but there is nothing like negative Babinsky sign)
Thanks for your explanation.
Just to confirm.. fanning of toes and extension of great toe is normally not seen because it is inhibited by the UMN .
Then how do we get the flexor response in normal adults?
I wish to know is it that: in this reflex, in healthy adults the same stimulus has two responses? plantar flexion is normally seen/visible and the inhibited extensor response which is latent
and in UMN , with the same stimulus the normal response of plantar flexion disappears and the now uninhibited extension response is seen?
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Clinical-Signs, Nervous-System-, Physiology-

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