Lumbar Puncture

Synonyms

Lumbar tap; Spinal puncture; Spinal tap

Definition

Lumbar usually refers to that part of the back or spine between the ribs and the pelvis. Lumbar puncture (LP) used to be called a spinal puncture or in common parlance a “spinal tap.” Before CT scans were invented, the majority of the “neurological” exam would have consisted of a 2 or 3 h history and physical, appropriate X-rays, and a lumbar puncture. Lumbar punctures could generate headaches, infections, or worse (i.e., herniation). With the advent of the much less invasive CT and MRI brain scans, the importance of the lumbar puncture as a diagnostic or treatment tool has greatly declined. It is now especially used for the evaluation of infectious, malignant or immunological disorders. It also has been used to evaluate suspected hydrocephalus through serial taps and CSF drainage. Prior to any LP, the clinician must assure the absence of increased intracranial pressure to avoid possible downward brain herniation. A lumbar...