anterolateral sulcus of spinal cord anterolateral sulcus of spinal cord the anterolateral sulcus of spinal cord is a landmark on the anterior side of the spinal cord. it denotes the location at which the ventral fibers leave the spinal cord. anterolateral sulcus of spinal cordspinal cord (ventrolateral sulcus is "s5")detailsidentifierslatinsulcus anterolateralis medullae spinalista98a14.1.02.010ta26054fma79877anatomical terms of neuroanatomy the anterolateral sulcus is less visible than the posterolateral sulcus.