Periradicular infiltration for sciatica: a randomized controlled trial. (University Hospital of Oulu, Helsinki, Finland). Spine. 2001;26:1059–1067.

In this study, 160 consecutive, eligible patients with sciatica who had unilateral symptoms of 1 to 6 months duration, and who never underwent surgery were randomized for a double-blinded injection with methylprednisolone bupivacaine combination or saline. Objective and self-reported outcome parameters and costs were recorded at baseline, at 2 and 4 weeks, at 3 and 6 months, and at 1 year. Recovery was better in the steroid group at 2 weeks for leg pain, straight leg raising, lumbar flexion, and patient satisfaction. Back pain was significantly lower in the saline group at 3 and 6 months. Sick leave and medical costs were similar for both treatments, except for cost of therapy visits and drugs at 4 weeks, which were in favor of the steroid injection. By 1 year, 18 patients in the steroid group and 15 in the saline group underwent surgery. Conclude improvement during the follow-up was found in both the methylprednisolone and saline groups. The combination of methylprednisolone and bupivacaine seems to have a short-term effect, but at 3 and 6 months, the steroid group seems to experience a "re-bound" phenomenon.