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The gracile and cuneate nuclei are the targets of the DRG axons that form the dorsal column pathway. The lowest cord segments contribute to the most medial part of the Gracile N. and decussates first followed by the leg, thigh, buttock, and lower trunk. The cuneate nuclei send out axons connected from DRG of the upper trunk, arms and neck and project as internal arcuate fibers crossing ventral to the canal forming the dorsal 1/2 of the medial lemniscus on the opposite side. All internal arcuate fibers (axons of dorsal column nuclei) cross the midline to the medial lemniscus that is positioned directly dorsal to the pyramid. The lower extremity is most ventral and the upper extremity is most dorsal.