Saint Thomas Health's Medical Mondays
Monday, November 5, 2012
TOPIC: Back Pain | Non-Surgical Treatment
Chad L. Calendine, MD | radiologist
Premier Radiology | SAINT THOMAS IMAGING NETWORK
News notes via www.webmd.com
Epidural steroid injections for lumbar spinal stenosis
How It Works
An epidural steroid injection (ESI) is a combination of a corticosteroid with a local anesthetic pain relief medicine. Corticosteroids are strong anti-inflammatory medicines used to relieve pain. The local anesthetic medicine helps give you immediate pain relief. Corticosteroid medicines take longer to have an effect.
Within the spinal canal, an ESI is injected into the space around the spinal cord and nerve roots (epidural space). The injection does not go into the membrane (thecal sac) that contains the spinal cord and nerve roots.
ESIs sometimes are used to treat pain and inflammation from pressure on the spinal cord. ESI is usually not tried unless symptoms caused by lumbar spinal stenosis have not responded to other nonsurgical treatment.
Imaging tests, such as magnetic resonance imaging (MRI) or computed tomography (CT) scans, should be done before you are given the injection. These tests are used to identify the exact location where nerve roots are being squeezed. During the injection, an X-ray machine (fluoroscope) is often used to guide placement of the needle.
Why It Is Used
An epidural steroid injection (ESI) may be tried when other nonsurgical treatments have failed to relieve severe leg pain from lumbar spinal stenosis.
The corticosteroids in an ESI can help provide relief from leg pain by reducing swelling and inflammation. Local anesthetics help relieve pain but do not reduce inflammation. Lidocaine can also help relieve pain quickly, before the corticosteroid has taken effect.
How Well It Works
Lumbar spinal stenosis may cause pain that radiates from the lower spine to the hips or down a leg. Epidural steroid injections (ESIs) are used for leg pain rather than back pain from lumbar spinal stenosis.
Steroid injections can help relieve pain for a short time (2 to 3 weeks) in some people. Experts do not know how well injections work over longer periods of time.1 Some people get enough pain relief that they can delay or no longer need surgery.2
These injections may relieve symptoms and reduce inflammation but do not cure spinal stenosis.
Epidural steroid injections (ESIs) should be used with caution. This treatment may only relieve symptoms for a short time, and the long-term effects are not well studied. Most experts recommend that no more than 3 ESIs be given in a 12-month period. Doctors usually wait at least 2 months between injections. And they do not usually give more than 3 or 4 injections into one area.
If side effects occur, they are usually minor and may include:
More serious side effects are very rare but can include bleeding, infection, nerve root injury.
People who have an increased risk for infections, such as those with diabetes or those with immune system problems, may be at a higher risk for problems from ESIs. People with mental health disorders may also have a higher risk for problems from this treatment.
Injections for Back Pain Relief
Injecting medicines to reduce back pain and inflammation is helpful for some people. The injections usually consist of a steroid and a numbing medicine.
However, it's important to keep in mind that not everyone gets the same relief.
Injections for Back Pain
Back injections may help treat two major back pain problems: radiculopathy and spinal stenosis. Doctors also use injections for other types of back pain. Sometimes, they also use them to help find out what's causing the pain.
Radiculopathy refers to inflammation or damage to a nerve usually in the neck or the low back. The problem originates where the nerve exits the spine. With radiculopathy, sharp pain shoots from the lower back down into one or both legs or from the neck into the arm. A herniated disc can cause radiculopathy.
With spinal stenosis, the lower spine becomes narrowed. As a result, it compresses the nerves inside. This usually causes pain in the buttock or leg and may or may not be accompanied by back pain. The pain from spinal stenosis may increase with activity. It may also lessen when you lean forward.
Medications for back pain can be injected into the area around the inflamed or damaged nerves. There are several kinds of injections, including:
Epidural Injections for Back Pain
Epidural means "around the spinal cord." Typically, epidural injections are performed in a doctor's office or the hospital. They're usually given by anesthesiologists, physiatrists, or interventional radiologists with special training.
Before receiving an epidural injection, you will probably undergo an imaging test. This may involve a CT scan or an MRI of the back. The test allows the doctor to identify possible causes of back pain.
At the doctor's office, you will lie face down on a table or special bed. The doctor might give you a sedating medication. But sedation is not usually necessary. The epidural injection takes place in several steps:
The epidural injection is usually not painful because of the numbing medicine used at the start. Many people do have mild tenderness for up to a few days after the injection.
Nerve Block Injections for Back Pain
In a nerve block, a doctor injects the area around the nerve with a numbing medicine, or anesthetic. Lidocaine is the most common anesthetic used. After a nerve block injection, a person will usually rapidly experience numbness with near-complete pain relief. The numbness wears off, though, after several hours.
Some doctors use nerve block injections to try to diagnose what's causing the back pain. If your doctor does this, you'll be asked which injection causes the back pain to go away. That nerve may then be chosen for an epidural injection with both steroid and anesthetic medicine. Or the doctor may decide to try another treatment.
Nerve blocks are also performed as anesthesia during surgery or other medical procedures.
Discography Injections to Diagnose Back Pain
In some people back pain is caused by a damaged disc between spinal bones, or vertebrae. In discography, a doctor injects contrast dye into a spinal disc. The doctor then observes the disc on an X-ray video screen. If contrast dye leaks out of the disc, and the person's usual back pain occurs, the test is considered positive. Clinical studies, however, have not shown that discography is always a helpful test.
Risks of Injections for Back Pain
Mild soreness or pain at the site after an injection for back pain is common. Headache, nausea, and vomiting can also occur. In rare cases, injections can cause significant bleeding or infection. You should discuss these and any other possible risks with the doctor before having an injection.
Nerve Block for Pain Relief
A nerve block relieves pain by interrupting how pain signals are sent to your brain. It is done by injecting a substance, such as alcohol or phenol, into or around a nerve or into the spine.
Nerve blocks may be used for several purposes, such as:
Nerve blocks are used to treat chronic pain when drugs or other treatments do not control pain or cause bad side effects. A test block is usually performed with local anesthetic. If you achieve good pain relief from the local anesthetic, your doctor may inject a nerve block, such as alcohol or phenol.
What To Expect After Treatment
Nerve blocks numb the nerves touched by the drugs. This relieves pain by interrupting the pain signal sent by the nerves to your brain. Depending on the type of nerve block, your pain may be numbed for a short time or a long time.
Nerve blocks for chronic pain may work for 6 to 12 months. They may have to be repeated.
Why It Is Done
Nerve blocks are used to diagnose the causes of pain. They also are used to treat chronic pain when drugs or other treatments cause bad side effects or do not control pain.
How Well It Works
Nerve blocks often relieve pain. Nerve blocks work well for some types of cancer pain, such as pain from cancer in organs such as the pancreas.1
Nerve blocks can cause serious complications, including paralysis and damage to the arteries that supply blood to the spinal cord. Other possible side effects include severely low blood pressure (hypotension), accidental injection of the alcohol or phenol into an artery, puncture of the lung, damage to the kidneys, diarrhea, and weakness in the legs.
Nerve blocks are not recommended if you have a disease that affects blood clotting, are taking blood-thinning drugs (such as heparin or warfarin), have a bowel obstruction, or have any type of uncontrolled infection.
Herniated Disc - Exams and Tests
Your doctor will evaluate your symptoms of leg and back pain using a medical history and physical exam. Your diagnosis will be based on any features that point to irritation of one or more spinal nerves and to the loss of strength, sensation, or reflexes that are normally associated with the nerve or nerves. If your medical history and physical exam suggest you have a herniated disc, you will probably not need additional tests during your first medical visit.
Follow-up tests sometimes used
Imaging tests may help confirm a diagnosis of a herniated disc or may be needed when nonsurgical treatment has not worked to relieve pain. If you still have symptoms after 4 weeks of nonsurgical treatment, your doctor may recommend imaging tests. If the results of an imaging test are not expected to change a treatment decision, the test is probably not needed.
Recommended Related to Back Pain
An MRI is generally preferred over a CT scan for diagnosing a suspected herniated disc in the lower back (lumbar spine).
X-rays generally are not useful or needed for diagnosing a herniated disc. But if your medical history and physical exam suggest a more serious condition (such as a tumor, infection, fracture, or severe nerve damage), or if your leg pain and other symptoms do not get better after 4 weeks of nonsurgical treatment, your doctor may order X-rays. Other tests, such as blood tests, may be done to rule out other conditions.
Follow-up tests occasionally used
The following imaging tests are not used as often as an MRI or a CT scan, but they may give your doctor additional information: