Posterior Median Sulcus Of The Medulla Oblongata Of The Brainstem, Anatomy

Description

Posterior median sulcus of the medulla oblongata forms a shallow midline groove on the dorsal surface of the brainstem, continuing superiorly from the posterior median sulcus of the cervical spinal cord. From this fixed posterior perspective, the sulcus lies medial to the paired dorsal column elevations, where the gracile fasciculus and cuneate fasciculus terminate in the gracile tubercle and cuneate tubercle of the closed (caudal) medulla. Inferiorly it approaches the cervicomedullary junction, while superiorly it fades as the medulla opens toward the floor of the fourth ventricle near the obex. Midline anatomy matters. Neurologically, this sulcus is the surface landmark for the dorsal midline partition between ascending posterior column pathways, making it a practical reference when teaching why lesions of the posterior spinal artery or dorsal medullary infarction produce ipsilateral loss of vibration and proprioception before the sensory decussation higher in the neuraxis. For operative planning and neuroradiology correlation, the posterior median sulcus helps orient the viewer on the back surface of the medulla oblongata when localizing dorsal exophytic tumors, cavernous malformations, or syringobulbia that expand toward the posterior surface while sparing more lateral brainstem tracts early. The restrained depth of the groove in this illustration supports accurate recognition without exaggerating topography. Use this illustration in neuroanatomy and clinical neuroscience courses to anchor discussion of dorsal column organization, brainstem surface landmarks, and how spinal cord midline cues extend into the caudal brainstem. It also suits textbooks and journal figures on posterior medullary stroke syndromes and dorsal approach corridors in brainstem surgery. Anatomical accuracy verified by SciePro's Medical Advisory Board.