Clinical Question

Is an epidural steroid injection or gabapentin (Neurontin) more effective for pain relief in patients with lumbosacral radicular pain due to a herniated disk or spinal stenosis?

Bottom Line

After controlling for the placebo effect that may accompany an epidural steroid injection, treatment with gabapentin is as effective as the injection in reducing radicular leg pain in the short term (three months). A placebo bump in response, if present, is likely to be transient. (Level of Evidence = 1b)

Synopsis

Patients enrolled in this study were recruited from eight hospitals in different areas of the United States and from a U.S. military facility in Europe. The 145 patients (74% men) had lumbosacral radicular pain due to a herniated disk or spinal stenosis for less than four years in duration, and the leg pain was as severe or more severe than back pain. The patients were randomly assigned, using concealed allocation, to receive gabapentin (titrated to between 1,800 and 3,600 mg per day in three doses for three months) or a single epidural injection of depomethylprednisolone, 60 mg, with a local anesthetic. To mask patients to their treatment, thereby minimizing the placebo effect of the procedure or the daily medication use, all patients took daily medicine and all patients received an injection, with the patients in the gabapentin group receiving a saline injection. After one month, pain scores had decreased similarly in both groups. Patients receiving the steroid had a slightly better response to a reduction in their worst leg pain scores (a decrease of three points vs. two points; P = .04) and were more likely to report a positive successful outcome (number needed to treat = 5). By three months, though, improvement was similar in both groups.

Study design: Randomized controlled trial (double-blinded)

Funding source: Foundation

Allocation: Concealed

Setting: Outpatient (specialty)

Reference: CohenSPHanlingSBicketMCet alEpidural steroid injections compared with gabapentin for lumbosacral radicular pain: multicenter randomized double blind comparative efficacy study. BMJ2015; 350: h1748.