For patients with radiculopathy or spinal stenosis, epidural corticosteroid injections are unlikely to provide effective pain relief, according to the study.
Lead study author Dr. Roger Chou, of the Oregon Health & Science University in Portland, and colleagues publish their findings in the Annals of Internal Medicine.
Low back pain is the leading cause of disability worldwide. In the US, around half of all workers admit to experiencing symptoms of back pain each year, and approximately 80% of us will suffer a back problem at some point in our lives.
Primary treatment for low back pain involves nonsurgical options, such as narcotic pain medication and nonsteroidal anti-inflammatory drugs (NSAIDs). Other nonsurgical treatments include epidural corticosteroid injections, administered directly to the epidural space in the spine.
Epidural corticosteroid injections work by reducing inflammation and, in turn, relieving pain. According to Dr. Chou and colleagues, the injections are commonly used for radiculopathy (inflammation of a spinal nerve) and spinal stenosis (narrowing of the spinal canal) - two conditions that cause radiating low back pain.
Use of epidural corticosteroid injections for these conditions is increasing, despite the fact that numerous studies have questioned their effectiveness for low back pain.
Epidural corticosteroid injects had no effect on spinal stenosis
For their study, the team reviewed 30 trials assessing the short- and long-term effects of epidural corticosteroid injections for individuals with radiculopathy or spinal stenosis, comparing them with a placebo.
Specifically, the researchers looked at how epidural corticosteroid injections impacted patients' pain, function and risk for surgery.
Fast facts about back pain
- Around 31 million Americans experience back pain at any given time
- Back pain is one of the most common reason for missed work days, and it is the second most common reason for doctors' visits
- Back pain costs Americans around $50 billion annually.
While the injections provided greater immediate pain relief for radiculopathy than a placebo, the team found that this effect was small and short term. What is more, the treatment did not prevent patients' need for surgery in the long term.
For spinal stenosis, the researchers found epidural corticosteroid injections offered patients no significant pain relief compared with placebo.
These findings remained regardless of what injection techniques and corticosteroids were used, according to the authors.
"We found that the injection technique used (transforaminal, interlaminar, caudal), type or dose of corticosteroid, selection of patients with imaging guidance, and other patient and technical factors had no impact on the findings," Dr. Chou told Medical News Today. "Really, the results were the same no matter how you sliced the data."While severe side effects from corticosteroid injections were rare, some minor side effects were identified, which included bleeding, blood clots and nerve root irritation.
Explaining why epidural corticosteroid injections appear to be ineffective for radiculopathy and spinal stenosis, Dr. Chou told us:
"Corticosteroids are supposed to reduce inflammation and associated swelling. Perhaps it is that inflammation is not a prominent factor in most patients. It's also possible that patients improve over time with or without a treatment. Finally, we know that low back pain treatments have strong placebo effect, so that could be what we're seeing."
Patients should be aware of alternative treatment options
Based on these findings and those from previous studies, Dr. Chou told MNT it is important patients are aware of alternative treatment options for both radiculopathy and spinal stenosis:
"I think that it's important for patients to understand that the benefits of epidural corticosteroid injections for radiculopathy appear small and short-lived.
Patients should be aware of options that range from simple analgesics like acetaminophen or NSAIDs, exercise and non-pharmacological therapies like manipulation, massage, acupuncture etc., and surgery - for which there is evidence of benefit. For some patients, the short-term benefits might be worth it, if they have tried noninvasive therapies and aren't interested in surgery or not a good candidate."
"For spinal stenosis," he added, "the evidence to date indicates no benefit, so it would seem appropriate to consider the alternatives described above."
However, the results of this study have been met with some criticism. Dr. Zack McCormick, of the Northwestern University Feinberg School of Medicine in Chicago, IL, told Reuters that the trials analyzed in this research were of low quality, so the findings "cannot be applied to the realistic day-to-day practice of spine medicine."
He noted, however, that the aim of epidural corticosteroid injections is to improve short-term symptoms and quality of life for the patient, not to provide a long-term cure. As such, he says the treatment should "not be used as an isolated therapy."
Earlier this year, a study published in The BMJ found acetaminophen to be ineffective for lower back pain and osteoarthritis.