Lumbar disk herniation often presents with sciatica pain radiating from the lower back to the lower leg and foot. Though radiculopathic pain usually begins to resolve within 2-4 weeks with conservative management, the pain may persist for greater than 1 year in up to 30% of patients (BMJ 2007 Jun 23;334(7607):1313). Systemic steroids are often prescribed as part of conservative management, but data on the efficacy of this approach is limited (Rheumatology (Oxford) 2011 Sep;50(9):1603). A recent randomized trial compared oral prednisone vs. placebo for 15 days in 269 adults with acute radiculopathy due to lumbar disk herniation. The steroid dosing regimen consisted of prednisone 20 mg capsules given as 60 mg daily for 5 days, then 40 mg daily for 5 days, and then 20 mg daily for the final 5 days. Patients randomized to placebo received identical appearing capsules and dosing schedule. Nonsteroidal anti-inflammatory drugs were prohibited for 3 weeks following randomization.
For trial inclusion, patients were required to have radicular pain for ≤ 3 months, a herniated disk confirmed by magnetic resonance imaging (MRI), and an Oswestry Disability Index (ODI) score ≥ 30 indicating at least moderate disability (mean ODI score 51). The minimum clinically important difference was predefined as a 7-point difference between groups in the ODI score. At 3 weeks after randomization, the mean ODI score in patients randomized to prednisone decreased by 19 points compared to 13.3 points for patients receiving placebo (adjusted mean difference 6.4 points, p = 0.006). Predinsone was also associated with a greater number of patients achieving a ≥ 50% reduction in ODI score at this time point (33% vs. 19.8%, p = 0.01, NNT 8). By 52 weeks, the mean difference from baseline ODI scores was 37.8 points the prednisone group vs. 30.4 points for the placebo group (adjusted mean difference 7.4 points, p = 0.005). Prednisone did not improve pain scores at 3 or 52 weeks, but prednisone was associated with an increased risk of adverse events. At least 1 adverse event was reported in 49.2% of patients with prednisone vs. 23.9% with placebo (p < 0.001, NNH 4). Insomnia, nervousness, and increased appetite were all significantly more common with prednisone compared to placebo.
Treatment with prednisone resulted in a significantly greater proportion of patients having at least a 50% improvement their ODI scores at 3 weeks. Although the adjusted mean difference between groups was just below the 7-point minimum clinically important difference, mean outcomes can mask significant benefits for subgroups (although whether there is an identifiable subgroup that might be specifically targeted remains to be seen). Prednisone did not decrease pain or the risk of back surgery, and was associated with an increase in adverse events. Overall, these findings suggest that prednisone may improve disability in some patients with acute radiculopathy due to lumbar disk herniation, but it does not improve pain status, and will result in some type of adverse effect in nearly half of patients. Benefits and risks seem closely balanced and the decision to use steroids for this indication should be made on an individual basis.