An epidural steroid injection is an injection of an anti-inflammatory steroid (e.g., Kenalog) in the epidural space. The epidural space is not an injection into the spinal cord itself. The spinal cord and spinal nerves are in a “sack” containing clear fluid (cerebrospinal fluid). The area outside this “sack” is called the epidural space. An epidural steroid injection is not the same injection as a labor epidural, which is commonly given to women in labor.
When the nerves in the epidural space are irritated or pinched by a bulging disk, narrowed “nerve canal” or bone spur, the resulting inflammation can cause pain, numbness, or tingling. The steroid injected can reduce inflammation of nerves in the epidural space and thus reduce pain and other symptoms.
The actual injection takes only a few minutes. Please allow about an hour and a half for the procedure; this will include talking to your doctor before the procedure, signing the informed consent, positioning in the room, and observation by the recovery room nurse afterwards.
The injection consists of a mixture of local anesthetics (e.g., bupivacaine) and the steroid medication (Kenalog).
All of our procedures begin by injecting a small amount of local anesthetic through a very small needle. It feels like a little pinch and then a slight burning as the local anesthetic starts numbing the skin. After the skin is numb, the procedure needle feels like a bit of pressure at the injection site. If you experience any pain during the procedure, your doctor will inject more local anesthetic as needed.
No, we offer mild IV sedation to calm you and local anesthesia to numb the skin.
It is typically done with you lying on your stomach. Your blood pressure, heart rate, and oxygenation will be monitored. In addition to your doctor and the x-ray technician, there will be a nurse in the room at all times if you have any questions or discomfort during the procedure. The skin in the back is cleaned with antiseptic solution and then the procedure is done.
Immediately after the injection, you may feel your legs becoming slightly heavy or numb. You may notice that your pain may be gone or considerably less. This is due to the effect of the local anesthetic and lasts only for a few hours. Your pain may return and you may have some soreness at the injection site for a day or so. You should start noticing pain relief starting about 2-3 days after the procedure.
We advise the patients to take it easy for a day or so after the procedure. Perform the activities as tolerated by you. Your recovery room nurse will give you more instructions upon discharge.
Your doctor or recovery room nurse will discuss this with you.
The long-term effect of the medication cannot be predicted. Usually, the immediate effect is from the local anesthetic injected. This wears off in a few hours. The steroid starts working in about 2-3 days and its effect can last for several days to a few months.
The typical series of injections is for about three, spaced about a week apart. You should expect a gradual overall improvement in pain after each injection.
It depends upon your response.
It is very difficult to predict how helpful injections will be. Generally, patients who have “radicular“ symptoms (radiating outward or downward, like sciatica) respond better to the injections than patients who have only back pain. Patients with recent onset of pain may respond much better than ones with longstanding pain. Patients with back pain mainly from bony abnormalities (e.g., a bone spur pressing on a nerve root) may not respond as well.
Overall, this procedure has very few risks. However, as with any procedure, there are some risks and side effects you should know about. Commonly encountered side effects are increased pain from the injection (usually temporary), inadvertent puncture of the “sack” containing spinal fluid (may cause headaches), infection, bleeding, nerve damage, or no relief from your usual pain. Side effects of the injected steroid may include weight gain, increase in blood sugar (mainly in diabetics), water retention, suppression of your own natural production of steroids, or temporary suppression of your immune system.
The following patients should not have this injection: if you are allergic to any of the medications to be injected or if you have an active infection going on. If you are on blood thinners, please talk with your doctor.