What is posterior median sulcus?

The posterior median sulcus is a shallow groove that runs along the posterior (back) aspect of the spinal cord, dividing it into two symmetrical halves. It is situated on the posterior midline of the spinal cord and is continuous with the posterior median sulcus of the brainstem.

The posterior median sulcus marks the location where the posterior spinal artery, which supplies blood to the posterior aspect of the spinal cord, divides into two branches. The sulcus also contains the posterior septum, a small amount of connective tissue that separates the two halves of the spinal cord.

The posterior median sulcus is important for anatomical orientation and is used as a landmark in neurosurgery and spinal cord research. It is one of the features that differentiates the spinal cord from the brain, as the brain lacks a similar structure on its posterior surface.