Talk:Epidural space

cranial vs spinal
There are two epidural spaces, which are both important. Perhaps this article should refer to both. I propose:

In human anatomy, epidural space (from Ancient Greek ἐπί, "on, upon" + dura mater also known as "epidural cavity", "extradural space" or "peridural space”) may refer to either of two anatomical structures. One is the potential space between the outer lining of the brain (the periosteal layer of the dura mater) and the internal surface of the skull. The other is the actual space, containing lymphatics, spinal nerve roots, loose connective tissue, fatty tissue, small arteries, and a network of internal vertebral venous plexuses which lies between the outer lining of the spinal cord (the meningeal layer of the dura mater) and the internal surface of the spinal canal. When the term ‘epidural space’ is used without qualification, it usually refers to the spinal epidural space.

Relationship between the spinal and cranial epidural spaces
These two spaces are not joined together; they are separate anatomical structures. The dura mater of the cranial cavity has two layers, an inner ‘meningeal layer’ and an outer ‘periosteal layer’. It therefore delimits three spaces, the epidural space (outside the periosteal layer), the interdural space, between the two layers, and the subdural space, (inside the meningeal layer). The periosteal layer extends from the inside of the skull to wrap around the outside of the skull, where it is referred to as the periosteum. The meningeal layer, by contrast, extends down the spinal canal, encasing both the brain and the spinal cord. The spinal cord therefore has only one layer of dura mater, which delimits only two spaces, a ‘subdural space’, which is continuous with the subdural space of the cranium, and an ‘epidural space’, which is continuous with the interdural space of the cranium. — Preceding unsigned comment added by 130.56.72.15 (talk) 03:09, 20 August 2015 (UTC)

Periosteum in spinal canal
In Epidural_space, "the periosteal layer" is understood at first reading as a layer of the dura mater, due to other references in the same article to "layers" of the dura mater. Should this be modified (maybe "periosteum" instead of "periosteal layer"?) to clarify that the spinal dura mater consists of the meningeal layer only? This concurs with Dura_mater. — Quaeram (talk) 19:58, 18 April 2020 (UTC)