Editing Epidural administration (section)

=== Anatomy ===
[[File:Epiduraldiagram.png|thumb|[[Sagittal]] section of the spinal column (not drawn to scale). ''Yellow'': spinal cord; ''blue'': [[pia mater]]; ''red'': arachnoid; ''light blue'': [[subarachnoid space]]; ''pink'': [[dura mater]]; ''pale green'': epidural space; ''taupe'': vertebral bones; ''teal'': interspinous ligaments.]]
{{Main|Epidural space}}
An epidural is injected into the epidural space, inside the bony [[spinal canal]] but just outside the [[dura mater|dura]]. In contact with the inner surface of the dura is another membrane called the [[arachnoid mater]], which contains the cerebrospinal fluid. In adults, the spinal cord terminates around the level of the disc between L1 and L2, while in neonates it extends to L3 but can reach as low as L4.<ref name="episteroid">{{cite journal |last1=Schneider |first1=Byron |last2=Zheng |first2=Patricia |last3=Mattie |first3=Ryan |last4=Kennedy |first4=David J. |title=Safety of epidural steroid injections |journal=Expert Opinion on Drug Safety |date=2 August 2016 |volume=15 |issue=8 |pages=1031–1039 |doi=10.1080/14740338.2016.1184246|pmid=27148630 |s2cid=27053083 }}</ref> Below the spinal cord there is a bundle of nerves known as the [[cauda equina]] or "horse's tail". Hence, lumbar epidural injections carry a low risk of injuring the spinal cord. Insertion of an epidural needle involves threading a needle between the bones, through the ligaments and into the epidural space without puncturing the layer immediately below containing CSF under pressure.<ref name="episteroid" />