A lumbar puncture is used to take a sample of the cerebrospinal fluid from the lower back. This fluid flows around the spinal cord and the brain, and clears waste products. Levels of certain proteins ...

Medically reviewed by Brigid Dwyer, MD The lumbosacral joint, also called L5-S1, is a term used to describe a part of the ...

A lumbar puncture is a test to check the fluid that circulates around the brain and spinal cord. This is called the cerebrospinal fluid or CSF. A lumbar puncture can check for cancer cells or for ...