Clinical Question

Is epidural corticosteroid injection effective for reducing pain and improving function in patents with radicular low back pain or spinal stenosis?

Bottom Line

It is hard to figure out what to do with these results. On the one hand, steroid injection did not provide a significant benefit compared with placebo injection in patients with radicular pain or spinal stenosis. However, part of the reason for this may be the significant and sustained improvement of pain scores seen with the placebo injection. This improvement might reflect natural history, but it may reflect the ability of patients treated with either injection to reframe the pain, because short-term improvement in function was (unlike pain relief) quickly lost in patients treated with steroid or placebo injection. (Level of Evidence = 1a−)

Synopsis

To conduct this review, the authors searched two databases, including the Cochrane database, as well as reference lists and a trial registry. Two investigators independently reviewed studies for inclusion, considering randomized trials of epidural corticosteroid injection vs. placebo, other steroid, or other injection techniques for patients with radicular low back pain (sciatica) or spinal stenosis of any duration. They included periradicular injections. One investigator extracted the studies and a second checked the results for accuracy. Of the 63 studies, most (n = 40) were of fair quality and five studies were rated as high quality. In six studies of 701 patients, steroid injection provided, on average, immediate pain relief and functional improvement that was not clinically different from placebo treatment. There was no difference in pain and function at short-term (two weeks to three months) or intermediate-term (three months to one year) follow-up. There was no effect on symptoms of spinal stenosis. Pain scores were reduced to a greater degree initially with a steroid, but patients who received the placebo reported pain improvement at short-, intermediate-, and long-term follow-ups, essentially catching up with steroid-treated patients. For function, scores initially improved with steroid injection but then regressed.

Study design: Meta-analysis (randomized controlled trials)

Funding source: Government

Setting: Various (meta-analysis)

Reference: ChouRHashimotoRFriedlyJet alEpidural corticosteroid injections for radiculopathy and spinal stenosis: a systematic review and meta-analysis. Ann Intern Med2015; 163( 5): 373– 381.