A lumbar puncture (LP) is a diagnostic and/or therapeutic procedure performed by inserting a hollow needle into the subarachnoid space of the lumbar (lower back) area of the spine that carries cerebrospinal fluid between the the brain and spinal cord. This procedure may be done for several reasons. It may be done to diagnose certain diseases or disorders. Some examples of those include (but are not limited to): Meningitis, Encephalitis, Subarachnoid Hemhorrage, certain cancers of the brain and spine, Myelitis, Neurosyphillis, and demyelinating diseases or disorders. It may also be used to obtain the opening pressure of the cerebrospinal fluid. A LP may also be used to administer certain medications (such as chemotherapeutic agents), spinal anesthetic, and contrast dye. A lumbar puncture is also frequently called a spinal tap, spinal puncture, and thecal puncture.
Though many consider the risks and complications for lumbar punctures to be relatively small, there are contraindications noted by many scholars in certain patient populations, such as those who have a Chiari Malformation or a heritable disorder of connective tissue, including but not limited to Ehlers-Danlos syndrome and Marfan’s syndrome. In this patient population, great care and consideration should be taken to minimize the risks associated with lumbar punctures; as well as to determine if an LP is truly medically necessary. LP’s should be avoided, if at all possible in those with these disorders. However, in the cases of medical necessity or a life threatening situation, it is not always possible to avoid them. Thus, the size of needle, method of insertion, amount of fluid collected by spontaneous drip only should be considered and adjusted to minimize risks and complications associated in this patient population. Additionally, lumbar punctures in this patient population should always be performed under fluroscopy by a competent physician. Patients and physicians should be aware of the more common complication of Post Dural Puncture Headache (PDPH) and cerebrospinal fluid leaks and both their acute and chronic symptoms (which very greatly between the acute and chronic phases).