The decussatio pyramidum refers to the portions of the corticospinal tract that cross to the contralateral side in the ventral medulla oblongata and descend in the spinal cord as the lateral corticospinal tract, while the uncrossed fibers continue ipsilaterally in a caudal direction as the anterior corticospinal tract.
Anatomy
The decussatio pyramidum is located in the lower ventral medulla oblongata and contains approximately 70–90 % of the fibers of the corticospinal tract that cross to the contralateral side.
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