A lumbar puncture is a procedure in which a hollow needle is inserted between the bones of the lower back and into the fluid around the lower part of the spinal cord. A sample of the fluid is then drawn off to be examined in the laboratory.
A lumbar puncture is carried out by a doctor or specially trained nurse. It can be done in the outpatients department or on a ward at the hospital. Lumbar punctures are usually carried out under local anaesthetic. However, lumbar punctures for children are sometimes carried out under general anaesthetic.