The spinal cord and spinal roots are enveloped by three layers of meninges. Meninges consist of pia mater, attached to the nervous tissue surface; arachnoid, bounding a subarachnoid space that is filled with cerebrospinal fluid; and dura mater, a highly fibrous membrane which is surrounded within the vertebral canal by an epidural space that contains fat.

The spinal cord is suspended within subarchnoid space and dura mater by denticulate ligament ,a bilateral thickening of pia mater (not shown below).