Lumbar puncture for diagnosis and treatment

An epidural or lumbar puncture is a routine medical procedure used to collect samples of cerebrospinal fluid. It is an important diagnostic tool and is generally considered safe, although it carries some risks. Because some people have trouble getting into the position needed for a lumbar puncture, doctors also use alternative methods when needed.

Lumbar Puncture Procedure

During an epidural, the patient lies on his side with the chin, hips and knees pulled into the chest to open up the space between the vertebra as much as possible. Once they are positioned, the doctor applies a local anesthetic to the patient’s lower back. When the area is numb, the doctor inserts a thin, hollow needle between two lower vertebrae to access the cerebrospinal fluid (CSF), which surrounds the brain and spinal cord.

When the doctor gets the needle in the right place, they determine the pressure of the cerebrospinal fluid and take a small amount for a sample. The procedure takes about 45 minutes and recovery is quite simple.

Surgeon, In, Blue, Surgical, Dress, Uniform, Doing, Lumbar, Puncture

CSF samples

Doctors use the cerebrospinal fluid (CSF) samples obtained from lumbar punctures for diagnosis inflammatory or cancerous disorders and infections involving the central nervous system.

These conditions include meningitis, brain cancer, bleeding between the brain and the tissues that cover it, and inflammation of the spinal cord. Doctors may also use epidural to investigate symptoms such as headaches when they have unknown causes, and to evaluate diseases that affect the covering of nerve fibers, such as multiple sclerosis.

gloved doctor researcher hand holding a bottle of cerebrospinal fluid

Other applications

In addition to taking a CSF sample, doctors can also use a lumbar puncture to inject medicines directly go inside the spine, such as anesthetics before spinal surgery or chemotherapy drugs. In some cases, X-rays and other scans require contrast dye to get an accurate picture, and doctors may also inject the dye with this procedure.

Hands of operating room personnel performing surgery


Once the doctor has obtained a CSF sample through an epidural it goes to the laboratory for analysis. Normal CSF is colorless. If the fluid is pink, cloudy, or yellow, it could indicate bleeding, while green CSF could mean an infection is present.

Samples are also checked for white blood cells, bacteria, viruses and sugar, as these things can also indicate an infection.

Scientist or biochemist holds cerebrospinal fluid test including glucose, protein, ADA


Spinal tapers or lumbar punctures are common, but because they involve the brain and spinal cord, watch out for complications is important. Some people experience numbness in their lower back or legs during or after an epidural and because the needle penetrates the skin, there is a risk of infection.

If too much fluid is drawn from the lumbar puncture, or if it leaks after the procedure, the person may develop a severe headache. These headaches usually start a few hours or days after the procedure and disappear when the person lies down.

Man with headache rubbing forehead

After the procedure

Immediately after a lumbar puncture or backbone, the person is instructed to lie flat to reduce the chance of developing a headache. Rolling from side to side is fine, but the person cannot sit up straight away.

Drinking plenty of fluids helps replace the CSF removed during the procedure. Patients sent home after the procedure should take it easy for the rest of the day and call the doctor if they notice numbness and tingling in the legs, have difficulty urinating, have persistent headaches, or see drainage or blood from the injection. Place.

Nurse with elderly male patient


People who should not have a lumbar puncture include those with spinal trauma, skin infections near the insertion site, and an increased risk of bleeding, either from a low platelet count, a bleeding disorder, or blood thinners taken within the last 24 hours.

When a doctor suspects increased intracranial pressure or increased pressure around the brain, they will order a CT scan before the lumbar puncture to determine the cause.

X-rays of the spine and abdominal area

Alternative to lumbar puncture

A safe alternative to a lumbar puncture is a lateral cervical puncture. This procedure is similar to a lumbar puncture. if the doctor inserts a long thin needle between the vertebrae to collect a CSF sample, but the needle goes between the cervical vertebrae at the top of the spine instead of the lower lumbar vertebrae.
A study shows that the fluid samples collected in this way were comparable to fluid obtained from a traditional lumbar puncture. This procedure may be a better option for those with an infection near or affecting the lumbar spine or those who cannot get into the correct position for a lumbar puncture.

A model of part of the spine in focus in the hands of a doctor in the blurred background.  A doctor or scientist refers to the spinous process as an anatomical part of the spine

Fluoroscopy Guided Lumbar Puncture

Fluoroscopy is a imaging technique which uses continuous X-rays to create a moving image, almost like an X-ray film. A fluoroscopy-guided lumbar puncture uses this imaging to guide the physician through the procedure.

A physician may choose this modified lumbar puncture procedure if there have been previous failed attempts at a standard lumbar puncture or if the patient has a condition that makes normal epidural surgery difficult, such as previous spinal surgery or obesity. This technique improves success rates and may reduce the chances of traumatic lumbar punctures, which occur when the procedure causes bleeding into the CSF.

word Fluoroscopy with check box

Ultrasound guidance

Another alternative to a traditional lumbar puncture used ultrasound guidance.

Fluoroscopy-led procedures are not ideal for everyone, especially pregnant women concerned about radiation. Ultrasound creates an image using sound waves, eliminating that risk. One study found that ultrasound guidance successfully reduced insertion attempts and failed procedures, making it a viable option that is likely to become more common in the future.

Physiotherapist using ultrasound to treat patient's back