Lumbar Puncture: Understanding the Spinal Tap Procedure and Location

A spinal tap, also known as a lumbar puncture, is a procedure that involves inserting a thin needle into the subarachnoid space in the lower back to collect cerebrospinal fluid (CSF) for diagnostic or therapeutic purposes. The subarachnoid space is located around the spinal cord and contains CSF, which bathes the brain and spinal cord. The procedure is typically performed at the L3-L4 or L4-L5 intervertebral space, which are the spaces between the third and fourth and the fourth and fifth lumbar vertebrae.