In real life, a spinal tap is a test that takes a small sample of spinal fluid for examination by sticking a needle into one of the body’s most sensitive areas. In a spinal tap procedure, a needle is inserted between the bones of the lower spine to “tap” into the liquid, much in the way sap is tapped from a tree.
While unpleasant, the test is usually safe and completed within a short period of time.
Spinal taps can be used to determine the presence of infections like spinal meningitis, bleeding in the brain, nervous system conditions like Guillain-Barre syndrome or multiple sclerosis. They can also be used to insert chemotherapy medications into the spinal fluid.
Cerebrospinal fluid (known by its initials, CSF) is the material the test withdraws. It is a colorless liquid that is used to transmit nutrients from the brain and spinal cord while acting as a protective buffer for both.
PERFORMING THE TEST
A spinal tap takes about 30 minutes to perform. While there may be a small pinching sensation when the needle is inserted, a spinal tap is usually not painful, although it requires that the patient lie still while fluid is withdrawn. The actual tapping procedure takes about five minutes.