The smallest worthwhile effect of surgery versus non-surgical treatments for sciatica: a benefit-harm trade-off study

Question: What is the smallest worthwhile (SWE) effect of discectomy compared with non-surgical treatments amongst people with sciatica? Design: Benefit-harm trade-off study. Participants: People with sciatica of any duration living in Australia and recruited through social media. Outcome: The outcome of interest was leg pain intensity. Participants were asked to nominate the additional percentage reduction in leg pain from discectomy––above the reduction anticipated from non-surgical treatments––that would make discectomy worthwhile for them. The SWE was estimated as the median (IQR) of the smallest percentage reduction in leg pain with discectomy (compared with non-surgical treatment) that participants considered worthwhile. The SWE was estimated for the overall sample and those with acute (≤ 6 weeks), subacute (> 6 to 12 weeks) and chronic (> 12 weeks) sciatica, and investigated factors associated with the SWE. Results: Two hundred participants with a mean age of 59 years (SD 12) were included. The SWE was estimated to be an additional 15% (IQR 10 to 40) reduction in leg pain with discectomy, beyond any reduction in leg pain achieved by non-surgical treatments. Dissatisfaction with previous non-surgical treatments and low pain self-efficacy were associated with smaller SWE estimates. Conclusion: People with sciatica would require discectomy to provide an additional 15% reduction in their leg pain beyond the expected 50% improvement in leg pain from non-surgical treatments in the short term to consider discectomy worthwhile. These results can inform the interpretation of the effects of discectomy in randomised trials and meta-analysis from the perspective of consumers.