decussation of the pyramids

variants: or decussation of pyramids

Definition of decussation of the pyramids

: pyramidal decussation An acute right-sided corticospinal system lesion above the decussation of the pyramids or a left-sided lesion below the decussation but above the seventh dorsal cord segment will abolish the left abdominal reflexes.— Robert T. Ross, How to Examine the Nervous System, 2006

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First Known Use of decussation of the pyramids

1810, in the meaning defined above

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The first known use of decussation of the pyramids was in 1810

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Cite this Entry

“Decussation of the pyramids.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2020.

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