What is an Epidural?
Spinal injections are not new — the use of spinal injections to treat low back pain was first documented in 1901, and in 1952 epidural steroid injections were first used to treat low back pain with associated sciatica (pain in the sciatic nerve due to lumbar disc herniation). Today, epidural steroid injections have become an integral part of non-surgical management of low back pain.
An epidural injection is typically used to alleviate low back and/or leg pain. While the effects of the injection can be temporary – providing relief from pain for one week up to one year – an epidural can be very beneficial for patients during an episode of severe back pain. Importantly, it can provide sufficient pain relief to allow the patient to progress with their rehabilitation program.
An epidural is effective in significantly reducing pain for approximately 75% of patients. It works by delivering steroids directly to the painful area to help decrease the inflammation that may be causing the pain. It is thought that there is also a flushing effect from the injection that helps remove or “flush out” inflammatory proteins from around the structures that may cause pain.
When is an epidural steroid injection typically recommended?
Epidural steroid injections for rehabilitation
In general, an epidural steroid injection is used to help provide pain relief to enable patients to progress with their rehabilitation. Individuals who have less back pain and feel more comfortable axe generally able to work on the active therapies—such as stretching, strengthening/pain relief exercises and low impact aerobic conditioning—that are critical in rehabilitating the lower back and helping prevent (or minimize) future episodes of low back pain.
Epidural steroid injections for pain
Several common conditions—including a lumbar disc herniation, degenerative disc disease, and lumbar spinal stenosis—can cause severe acute or chronic low back pain and/or leg pain. For these and other conditions that can cause chronic pain, an epidural steroid injection may be an effective non-surgical treatment option.
How to prepare for the injection?
The week before the injection you are not allowed to take any anti-inflammatories or blood thinners. This means you cannot take any aspirin, Plavix, coumadin, motrin, ibuprofen, naproxen or Aleve. The only anti-inflammatory that is safe is called Celebrex.
You will need a ride home from the injection. Sometimes after the procedure your leg may feel a little numb, so trying to press on the gas and/or brake may be difficult.
How is the epidural steroid injection performed?
Before the epidural steroid injection
An epidural steroid injection usually takes between 15 and 30 minutes. The patient lies flat on an x-ray table on their abdomen. Prior to the epidural injection, the skin is numbed with lidocaine, which is similar to the novocaine that the dentist uses (a “local” anesthetic).
Using fluoroscopy (live x-ray) for guidance, the physician directs a needle toward the epidural space. Fluoroscopy is considered important in guiding the needle into the epidural space, as controlled studies have found that medication is misplaced in 13% to 34% of epidural steroid injections that are done without fluoroscopy.
During and after the epidural steroid injection
Once the needle is in the exact position, the epidural steroid solution is injected. Following the injection, the patient is usually monitored for 15 to 20 minutes before being discharged to go home.
Patients are usually asked to rest on the day of the epidural steroid injection. Normal activities (those that were done the week prior to the epidural injection) may typically be resumed the following day.
What are the benefits of an epidural steroid injection?
Patients will find that the benefits of an epidural steroid injection include a reduction in pain, primarily in leg pain. Patients seem to have a better response when the epidural steroid injections are coupled with an organized therapeutic exercise program.
Pain relief from an epidural steroid injection
An epidural can not work at all, can last 2 minutes, 2 hours, 2 days, 2 weeks, 2 months, 2 years until forever. It is very difficult to predict, but as you will see a few paragraphs down, the risk of having a side effect from an injection is very unlikely; therefore the benefit outweighs the risk. —An epidural injection can be very beneficial for patients during an episode of severe back pain. Importantly, it can provide sufficient pain relief to allow the patient to progress with their rehabilitation program.
Epidural steroid injection success rates
An epidural steroid injection is generally successful in relieving pain for approximately 50-75% of patients. If a patient does not experience any back pain or leg pain relief from the first epidural injection, further injections will probably not be needed. However, if there is some improvement in back pain or leg pain, one to two additional epidural steroid injections may be recommended.
What are potential risks and side effects of an epidural steroid injection?
As with all invasive medical procedures, there are potential risks associated with lumbar (lower back) epidural steroid injections. Generally, however, there are few risks associated with epidural steroid injections and they tend to be rare. Risks may include:
- Infection: Minor infections occur in 1% to 2% of all injections.
- Bleeding: It is a rare and is more common for patients with underlying bleeding disorders.
- Nerve damage: While extremely rare, nerve damage can occur from direct trauma from the needle, or secondarily from infection or bleeding.
- Dural puncture: A dural puncture occurs in 0.5% of injections. It may cause a post-dural puncture headache (also called a spinal headache) that usually gets better within a few days. Although rare, a blood patch may be necessary to alleviate the headache.
- Paralysis is not a risk since there is no spinal cord in the region of a lumbar injection
Side effects of an epidural steroid injection
In addition to risks from the injection, there are also potential risks and side effects from the steroid medication. These side effects from an epidural steroid injection tend to be rare. Side effects from steroids are more common when taken daily for several months. Risks and side effects may include:
A transient decrease in immunity, high blood sugar, stomach ulcers, severe arthritis of the hips, (avascular necrosis), cataracts, transient flushing, and increased appetite.
How frequently can epidural steroid injections be performed?
There is no definitive research to dictate the frequency of how often a patient should have epidural steroid injections for low back pain and/or leg pain. In general, it is considered reasonable to perform up to three epidural injections per year.
Epidural steroid injection timing varies
Typically epidural steroid injections are done in two-week intervals. However, there is no general consensus in the medical community as to whether or not a series of three injections need always be performed. If one or two injections lessen the patient’s low back pain and/or leg pain, some physicians prefer to save the third epidural steroid injection for any potential recurrences of back pain.