Effectiveness of acupuncture in the treatment of chronic sciatica from herniated disks: a systematic review and meta-analysis

This systematic review and meta-analysis investigated the efficacy of acupuncture in the treatment of chronic sciatica caused by lumbar disk herniation, a condition that significantly affects patients' quality of life. Chronic sciatica has a global incidence that ranges from 1.6% to 43%, with 10% to 40% of cases progressing to a chronic condition that persists for more than 12 weeks. The researchers conducted a systematic search in four major databases (PubMed, EMBASE, Cochrane Library, and Web of Science) covering the period from May 2015 to May 2025. Eleven randomized clinical trials involving 868 participants were included, predominantly conducted in China.

The studies compared different acupuncture modalities (manual, electroacupuncture, and specific techniques) with control groups that included sham acupuncture, standard care, or conventional acupuncture. The primary outcomes assessed were pain intensity measured by the visual analog scale (VAS) and functional disability measured by the Oswestry Disability Index (ODI). The methodology followed PRISMA guidelines and used the Cochrane Risk of Bias 2.0 tool to assess study quality. Statistical analysis used fixed- and random-effects models as appropriate, with standardized mean difference (SMD) as the effect measure.

The results demonstrated that acupuncture significantly reduced sciatic pain compared with controls, with an SMD of -1.08 (95% CI: -1.41 to -0.75), exceeding Cohen's threshold for a large effect (d = 0.8). Subgroup analysis revealed consistent efficacy regardless of the type of control: sham acupuncture (SMD = -1.05), standard care (SMD = -1.02), and conventional acupuncture (SMD = -1.12). After exclusion of studies with high heterogeneity, eight studies (n=718) maintained significant efficacy with an SMD of -0.95 (95% CI: -1.10 to -0.79) and reduced heterogeneity (I² = 30.7%). For functional improvement, seven studies (n=621) demonstrated that acupuncture significantly outperformed controls on the ODI, with an SMD of -0.57 (95% CI: -0.84 to -0.31), reaching Cohen's threshold for a medium effect.

Sensitivity analysis using the leave-one-out method confirmed the robustness of the results, with SMD varying between -1.47 and -0.73 and maintaining statistical significance. Assessment of publication bias through funnel plot and Egger's (p=0.475) and Begg's (p=0.697) tests did not indicate significant bias. From a clinical standpoint, these findings suggest that acupuncture offers specific therapeutic benefits beyond the placebo effect, since efficacy was consistent even when compared with sham acupuncture. The observed effect size is clinically relevant and comparable to conventional therapies such as nonsteroidal anti-inflammatory drugs, but with a superior safety profile.

Despite the methodological heterogeneity observed among studies, related primarily to variations in acupuncture protocols, assessment tools, and types of control intervention, the consistent direction of effects strengthens the evidence of efficacy. Heterogeneity is inherent in meta-analyses of traditional medicine and does not invalidate efficacy conclusions when effects remain consistently favorable.