Epidural Steroid Injection (ESI)
An epidural steroid injection is a frequently-used treatment for chronic pain. This minimally-invasive procedure may provide profound pain relief where other conservative treatments have failed and can also help you avoid more interventional surgery. With epidural steroid injections, doctors use an injected pain reliever and an anti-inflammatory medication to reduce pain signals to your brain and relieve inflammation that affects the nerves of your spine.
A common characteristic among the syndromes treated with epidural steroid injections is a pain described as “radicular pain.” The word radicular means “root” and typically refers to an irritated nerve root (radiculitis) or weakness of an affected nerve root (radiculopathy).
Radicular pain is pain that radiates from the spine down an irritated spinal nerve root. Irritation of this spinal nerve in your lower back, called lumbar radiculopathy, can cause pain that typically travels down a leg. Likewise, cervical radiculopathy describes pain that travels from neck nerves down an arm.
Epidural injections can help treat nerve compression and damage in your neck (cervical spine), as well as the low back (lumbar spine). They’re best for moderate to short-term relief of pain. A major benefit of these types of injections, however, is that they allow you to undergo other pain relieving therapies.
Physical therapy, for example, may be too painful to do when you’re suffering from chronic pain. An epidural steroid injection manages your pain while you undergo physical therapy to treat the underlying cause of your pain.
Conditions commonly treated with epidural steroid injections include: degenerative disc disease, spinal stenosis, herniated discs, spondylosis and/or sciatica. Again, the most important benefit of the use of epidural steroid injections is the rapid relief of symptoms that allows patients to experience enough relief to become active again. With this help, patients can regain the ability to resume their normal daily activities.
Epidural steroid injections are considered routine and relatively painless. Approximately 72% of patients experienced immediate pain relief in a research trial that evaluated the usefulness of a cervical interlaminar epidural steroid injection in patients with neck pain and cervical radiculopathy. If pain relief is only moderately achieved with the first injection, then another injection can be given in two weeks that may provide additional relief.
The use of multiple injections was studied by the Department of Anesthesiology and Intensive Care at the University of Pavia, Italy. They concluded that therapy with multiple epidural steroid injections provide better control of chronic neck pain compared to that with a single injection. If you experience neck pain, your doctor may recommend multiple epidural steroid injections (often completed in sets of three).
The Department of Rehabilitation Medicine at the University of Washington conducted a study that compared the risks and efficacy between surgical alternatives versus lumbar epidural steroid injections (ESIs). In their conclusion, they noted that: “When weighing the surgical alternatives and associated risk, cost, and outcomes, lumbar epidural steroid injections are a reasonable non-surgical option in select patients.”
Types
There are several types of epidural steroid injections, and the specific type you receive depends on the cause of your pain. Your doctor will decide which procedure is most beneficial to you after reviewing your history, performing a physical exam, and determining the cause of your pain.
The main difference in the types of epidural steroid injections is the position where the needle inserts as well as the amount of nerve roots treated.
Intralaminar injections - An intralaminar injection occurs in the mid-line of your back between your spinous processes (most prominent bones in the mid-line of your spine). The needle enters between the lamina of two vertebrae through the back of your vertebrae (as opposed to the side). The combination of steroid and anesthetic is delivered into the epidural space in the midline and spreads to the nerve roots on both sides of your spine. The evidence for interlaminar epidural steroid injections is strong for short-term relief, however the evidence is limited for long-term relief in managing radiculopathy.
Transforaminal injection- This type of epidural steroid injection enters through the side of your vertebra above the opening for the exiting nerve root where the pain is thought to originate. This approach treats one side at a time and is typically more specific. Pain specialists often use these for patients who have undergone previous spine surgery and have foreign bodies (surgical pins, surgical rods, or screws) as well as previous scarring. This type of injection allows them to avoid these structures. Transforaminal ESIs are especially effective for short-term and moderate improvement in managing lumbar back pain.
Caudal injection - Caudal injections are delivered into the epidural space by your tailbone. This technique allows for a catheter to be placed (Racz catheter) and larger volumes of steroid and anesthetic to be delivered. The additional medication can be used to treat more nerve roots that are going to the inflamed area at the same time. Often caudal epidural steroid injections are combined with another procedure called lysis of adhesions (also known as the Racz procedure), which is used to treat epidural scarring.
Overview
The epidural steroid injection procedure is generally painless and begins with your doctor sterilizing the injection area. You may be positioned on your side or your stomach to receive the injection.
Once the area to be injected is prepared with a local anesthetic, your doctor will inject medication into the epidural space (the space between your spinal cord and vertebrae) where irritated nerve roots are located.
This injection includes both a long-lasting steroid and a local anesthetic (i.e., lidocaine or bupivacaine). The steroid reduces inflammation and irritation. The anesthetic works to interrupt the pain-spasm cycle and nociceptor (pain signal) transmission. The combination medicine then spreads to other levels and portions of the spine, reducing inflammation and irritation.
The entire procedure usually takes less than 30 minutes. Watch a cervical epidural steroid injection below.
Risks
Epidural steroid injections are considered an appropriate non-surgical treatment for many patients who suffer from back and neck pain. Although epidural steroid injections are generally safe and a commonly-performed procedure, there are still risks.
The major risks associated with this procedure include: bleeding, infection, post-dural puncture headache, and/or nerve damage. The other risks of epidural steroid injections relate to the medications. For example, some of the potential side effects of corticosteroids include: elevated blood sugar, weight gain, anxiety, arthritis, stomach ulcers, bone loss in post-menopausal women, and/or brief decrease in immune system function. Before treatment, you should talk with your doctor and inform them of any potential risk factors or allergies.
Patients with an allergy to any anesthetic, are on blood thinning medications, have an active infection, or are pregnant may not be able to receive epidural steroid injections.
Recovery
Some patients may experience relief that lasts from just a few weeks to a full year with one injection. Others may require multiple injections several weeks apart. Each patient is different and will have a different response.
For all patients, taking the day of the procedure off to rest is a good idea. You may experience some pain around the injection site. Treat this with ibuprofen and ice packs. Do not drive on the day of the injection, and take your time to gradually return to normal levels of activity.
If you experience a fever, increased pain around the injection site, or just generally feel unwell, give your doctor a call. This could be a sign of infection or reaction to the medications.
The amount and duration of pain relief vary from person to person is dependent on many factors, including the cause of your pain, health history, and activity level.
Some may find relief that lasts for years while others have short-term relief. It is important to discuss with your physician your response to epidural steroids in order to plan future treatment options.
