spinal dura mater[TA]
single-layered strong membrane, comparable and continuous with (at the foramen magnum) the meningeal layer of the intracranial dura mater of the brain. It does not (in contrast to the dura mater of brain) adhere to the enveloping bony structures (vertebrae) or their periosteum, being separated from the latter by a considerable space, the vertebral epidural space-a true space containing the internal vertebral venous plexus embedded in a matrix of epidural fat.
endorrhachis(ĕn″dō-rā′kĭs) [Gr. endon, within, + rhachis, spine]
The membrane lining the spinal canal.