July 3, 2014
News Review From Harvard Medical School -- Steroid Shots May Not Improve Back Pain
A new study suggests that steroid shots may not help people with a common back pain problem. The study focused on spinal stenosis. With this condition, the open space in the spinal canal is narrowed. This squeezes nerves, causing pain. Doctors sometimes give injections of a corticosteroid to reduce swelling and inflammation. This is combined with a local anesthetic such as lidocaine to numb the area as the shot is given. The new study included 400 people with back and leg pain from spinal stenosis. They were randomly divided into 2 groups. One group received either 1 or 2 injections that contained a steroid plus lidocaine. The other group got injections of lidocaine only, without the steroid. Six weeks later, there were no differences between the groups in their levels of pain or function. About two-thirds of people who got the steroid injection were satisfied with their treatment. Just over half of the lidocaine group reported being satisfied. The New England Journal of Medicine published the study. HealthDay News wrote about it July 2.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Back pain is remarkably common. Most people, at some point in their lives, will have back pain severe enough to seek medical attention.
Standard medicines and physical therapy don't always reduce the most common types of back pain. When that happens, spinal injections are often used. Generally, they include a corticosteroid drug plus a numbing medicine, such as lidocaine. Doctors use high-tech pictures to guide the needle. Injections are made into the joints at the back of the spine or into the space near the spinal cord.
The goal is to reduce inflammation and interrupt the pain signals from compressed or irritated nerves. It's considered a safe treatment as long as proper precautions are taken and the injections aren't repeated too often.
But a new study calls into question just how good these injections are for one spinal condition, lumbar spinal stenosis.
With this condition, the spinal cord in the lower back is compressed. Causes include arthritis, calcium buildup in ligaments and disk disease. Sometimes the narrowing is present from birth and gets worse with age. Symptoms include pain in the back, legs or both. The pain is worse when standing or walking and better when sitting or leaning forward.
The definitive treatment is surgery. This is a major operation. Therefore it's usually considered a last resort.
In this new study, researchers gave epidural injections to 400 people with lumbar spinal stenosis. They used either the standard combination of drugs or lidocaine alone. Lidocaine is a short-acting anesthetic that would not be expected to provide lasting relief. So, the lidocaine-only treatment is a useful comparison group.
Six weeks later:
- People in both groups reported improvement. For example, on a scale of 0 to 10, the average person's pain improved from 7 to 4.5.
- Those receiving both drugs did not report any more improvement in pain than those receiving lidocaine alone.
- Responses to questions about disability were similar between the two groups.
- There were more reported side effects (including headache and infections) in the combination treatment group. Side effects were minor and did not last.
Despite these findings, I think it's too soon to give up on these injections. Here's why:
- Although the two treatment groups were similar at 6 weeks, both groups were better than before the injections.
- A majority of patients were satisfied with their treatment. More people receiving the combination treatment reported satisfaction than the lidocaine-only group (67% vs. 54%).
- People in this study had moderate to severe leg pain and disability. Others who had milder symptoms or different spine conditions might be more responsive to treatment.
- People received only 1 or 2 injections over 3 weeks. It's common to offer a third injection, especially if there was at least some improvement with the first ones.
- The study was not large enough to predict which people are more likely to improve than others.
Still, if other researchers confirm these findings, we may need to reconsider this common treatment. And that's a big deal for the millions of people who receive these injections in the United States each year.
What Changes Can I Make Now?
See your doctor if you have unexplained and lasting back or leg pain. It's important to do this right away if you have "red flag" symptoms such as:
- Recent, significant trauma
- A prior history of cancer
- Leg weakness or numbness
- Loss of ability to control your urine or bowels
- Unexplained weight loss
The common causes of back pain, such as arthritis or muscle spasm, can usually be well-treated with conservative measures. These include:
- Analgesics, such as acetaminophen (Tylenol and others)
- Anti-inflammatory medicines, such as ibuprofen or naproxen
- Muscle relaxants
- Physical therapy or stretching
If your doctor recommends epidural steroid injections, ask about this study. As with any elective procedure, discuss the risks, benefits and other treatment options.
In 2012, a multistate outbreak of fungal infections after epidural steroid injections affected 751 people. These infections caused 64 deaths. It was a reminder that serious complications can occur. This outbreak was traced back to contaminated medicines from a Massachusetts compounding pharmacy that did not follow standard precautions. Fortunately, such infections are quite rare.
What Can I Expect Looking to the Future?
This study may lead to a drop in the popularity of epidural steroid injections. This may be appropriate. But the study also raises question for future research to address:
- Should injections be offered that contain only lidocaine?
- Is it possible to identify which people are most likely to be helped by epidural spinal injections?
- If steroid injections don't help, what else can a person with lumbar spinal stenosis do (short of surgery) to get relief?
We need larger and longer-term studies to sort out the role of these injections for spinal stenosis and other spinal conditions.