Epidural steroid injections (ESIs) are one of the most common procedures done for pain that originates in the lumbar (low back) or cervical (neck) spine, sometimes in the thoracic (mid back). When done by an experienced, skilled physician, ESIs are safe and effective for some of the most common types of pain. We’ll talk a little about ESIs today – but keep in mind that this is not an exhaustive coverage of ESIs, and your particular situation should be discussed with your provider before you make a decision on whether the procedure is right for you.
First, a little bit about the spine. The bones of the spine look almost like closed padlocks that are laid flat and stacked up on each other. There are squishy cushions (the disks) between the bodies of the padlocks, and the spinal cord runs through the stacked-up loops of the padlocks. Large nerves leave the spinal cord, exiting the spine through the spaces between the padlock loops. These large nerves travel to specific parts of the body, in a fairly predictable pattern.
Got the general picture? Now imagine that one of the squishy cushions gets a little flat and starts to bulge out, or develops a bubble on it that protrudes out, or even gets a little rip in it so that the jelly inside the cushion starts to leak out a little. And imagine that the bulge or protrusion or leaked material starts to push on the spinal cord, or on one of the large nerves leaving the spinal cord. It turns out that when this happens it can be really painful, and the pain is perceived as running along all or part of where the large nerve runs.
Epidural steroid injections are used to put a steroid medication and a local anesthetic around where the nerve is irritated, with the intent of calming the area, reducing inflammation, and opening things up a little, so the nerve can function more normally. ESIs do not fix the disk (sometimes the body will do that, but it can take months or years), but the procedure can reduce pain, and sometimes reduce numbness, pins-and-needles sensations, and tingling. There is a lot of research indicating that ESIs can provide relief for weeks or months, with minimal risks, and may allow people to avoid having back surgery.
Sounds great, right? Most of us will agree that reducing pain is a good thing. But there are risks, and sometimes ESIs don’t work very well. Fortunately, the chance of bad things happening is minimal when the procedure is done by someone who knows what they are doing, and the chance of good things happening is pretty high when it is done for the right kind of pain.
Risks of ESIs are generally associated either with the needle or with the steroid. When ESIs are done by someone who is skilled and experienced, the risks associated with the needle are quite low, but can happen. We are, after all, putting a needle into an area that is already pretty cranky, and everybody’s anatomy is a little different. We use fluoroscopy, a type of X-ray that allows instant identification of where the needle is, and contrast dye to make doubly sure the needle is in the right place. In a study done a few years ago, 1,857 patients had a total of 4,265 ESIs, and there were no major complications noted. The most common minor complication was an increase in pain for a few days, which occurred in 2.4% of the ESIs. Another possible mild adverse effect includes weakness or limited paralysis that can last a few hours. More severe adverse effects, such as infection, bleeding, permanent paralysis or nerve/spinal cord damage, are extremely rare when ESIs are done in a sterile fashion by a skilled physician.
The idea of an epidural steroid injection is to put steroid medication right where it is most needed to reduce inflammatory processes, and this is mostly what happens. However, there is often some spread into the rest of the body where the steroid can cause side effects. Side effects are generally temporary, and go away once the steroid is cleared from the body, but can be bothersome.
- Facial flushing is a side effect that can occur in some people who are sensitive to it, and is more common in women than men. It usually lasts less than 48 hours, but can be uncomfortable while it occurs. An over-the-counter antihistamine may be helpful, if flushing is really bothersome.
- In people with diabetes or pre-diabetes, steroid injections can cause a temporary jump in blood sugars, and a temporary resistance to the effects of insulin. This is more common, and more of a problem, in people whose diabetes is poorly controlled, which is why we won’t do ESIs if blood sugars are high.
- Steroid injections can cause heavier and more painful periods in some women, and reduced fertility in men and women, due to changes in sex hormone levels.
- Steroids can reduce the immune system, which increases the chance of infection.
- A few adverse effects are more likely if too many steroid injections are given in too short a time. These include osteoporosis, mood changes like increased irritability, and insomnia. This is why we limit the number of ESIs a person can have in a year.
When ESIs don’t work
Remember the picture of the stacked padlocks? The spine isn’t really that simple, of course, and it can be really difficult to tell for sure where the origin of pain is, even when you can give us a good description of your pain pattern, and we do a good physical exam, and we have a recent MRI. When an ESI doesn’t seem to work, it might mean that we need to put another dose of medication in the area, or we might need to change exactly where we put the medication. It might also mean that we need to look for the origin of the pain in another place, or that the problem is severe enough that injections won’t help and we need to consider another kind of treatment. It’s important to keep your follow-up appointments so that we can evaluate what your response is, and what should be done next.
Epidural Steroid Injections: Pros and Cons
- ESIs can be helpful in a number of situations, but usually work best when pain is caused by irritation or compression of one or more of the large nerves that leave the spine.
- Remember that there can be an increase in pain for up to a few days after an ESI, and it can take 7-10 days to see a response.
- ESIs should be limited to no more than 3 in 3 months and 6 in 12 months, and should be avoided if you are a woman who is or is trying to get pregnant.
- There is a greater risk of adverse effects if your blood pressure or blood sugar levels are not controlled.
- It’s harder to do epidural injections safely and effectively in people who are very obese.
- Anticoagulant or antiplatelet medications increase the risk of bleeding into the spine during or after ESI – if it is not safe for you to stop this type of medication, you may not be a candidate for ESIs.
- ESIs are safer and more effective when done by an experienced physician, using fluoroscopy to visualize where the needle tip is, and using a small amount of contrast dye to verify placement of the needle.
- You should not drive for several hours after an ESI.
At North Shore Pain Management we provide advanced, evidence based, multidisciplinary and cost effective pain management. Our goal is to improve your ability to return to the activities you have been missing as well as provide a meaningful reduction in pain.