DEAR DOCTOR K:
I have terrible pain from sciatica. Will epidural injections help?
I wish I had a definite and non-controversial answer. But as with so many areas of medicine, not every study of that question comes up with the same answer. Some say “yes” and some say “no” — for the average patient in the study.
Sciatica is a persistent aching or burning pain felt along the sciatic nerve. The two sciatic nerves are the longest nerves in the body. They run from the lower back down through the buttocks and into each of the lower legs. The pain of sciatica can be severe. It can go away on its own, but for many people, sciatica is a chronic condition that keeps coming back.
Sciatica occurs when the sciatic nerve is pinched, irritated or injured. Inflammation, arthritis or a displaced disk in the lower spine are often to blame.
Doctors commonly treat sciatica with epidural injections into the spine. (The word “epidural” refers to a particular area in the spine.) The injections contain a steroid, which reduces inflammation. The injections can also contain a long-lasting painkiller.
The different causes of sciatica may be one reason that studies come to different conclusions. If a person’s sciatica is caused by inflammation rather than by arthritis, it may be more successfully treated by steroids — since the main effect of steroids is to reduce inflammation.
The best kind of study for any treatment procedure, like an injection of medicines, is a randomized trial that includes a sham procedure. In this kind of study, every person gets an injection but only some people, chosen at random, get an injection of the real medicine; the rest get just a placebo injected or nothing injected (a sham procedure).
One recent study found that there was only a short-term (one-month) relief of symptoms for most patients who got any relief (and not all did).
Another large recent study analyzed results from 23 previous studies comparing steroid injections to placebo (sham) injections. They found that for some people, an epidural injection gave good relief from leg pain (but not back pain) for several months. But for most people, the benefit was quite small. In addition, the pain relief did not last; after one year, there was no difference in pain between the sham and treatment groups.
Given the severity of your sciatica pain, it might be worth trying an epidural injection. But bear in mind that this treatment may offer only a small and short-lasting benefit.
In addition, you may have heard of the recent national outbreak of meningitis that was caused by epidural injections of steroids that were contaminated with fungus. This was a very unusual, but very serious, complication of the treatment. Some people might have had only brief or no pain relief. For them, the treatment was worse than the disease.
Talk to your doctor about whether simpler treatments such as exercises, physical therapy, compresses, painkilling medicines, chiropractic manipulation, massage, yoga or acupuncture might be worth considering.