BACKGROUND: Peripheral nerve stimulation (PNS) has emerged as a promising neurostimulation modality, yet its effectiveness and durability for chronic pain remain uncertain. We conducted a systematic review and meta-analysis to evaluate changes in pain intensity following implantable PNS therapy.
METHODS: Eligible studies included adults (=18 years) with chronic pain treated with an implantable PNS system, and pain intensity was assessed at baseline and follow-up time points. The primary outcome was change in pain intensity from baseline to 6 months after PNS implantation. Secondary outcomes included changes in pain intensity at 3, 12 and 24 months after PNS implantation. Standardized mean differences (Hedges' g) were pooled using a random-effects model.
RESULTS: A total of 106 studies comprising 9272 patients were included. PNS was associated with large, statistically significant reductions in pain intensity from baseline to all time points: 3 months (Hedges' g 2.92; 95% CI 2.62 to 3.21), 6 months (Hedges' g 3.08; 95% CI 2.68 to 3.48), 12 months (Hedges' g 2.68; 95% CI 2.30 to 3.05) and 24 months (Hedges' g 2.08; 95% CI 1.68 to 2.48) (all p<0.001). However, the certainty of evidence as assessed by the Grading of Recommendations Assessment, Development and Evaluation criteria was rated as low for the primary outcome, due to pooling from observational studies, risk of bias, and heterogeneity (statistical, clinical and methodological). Subgroup analyses revealed no differences by study design or device type, while smaller effect sizes were reported in industry-funded studies and those with declared conflicts of interest. The largest effect sizes were observed in pelvic and upper extremity pain, whereas the smallest in truncal pain.
CONCLUSION: Implantable PNS provides persistent and clinically meaningful analgesia for chronic pain, with benefits sustained up to 24 months. These findings support broader clinical adoption and provide evidence to inform pay0r coverage and policy decisions.
| Discipline Area | Score |
|---|---|
| Physician |  |
Physician rater
Very optimistic assessment of the results that are not particularly positive. RAPM is not what it used to be.
Physician rater
This methodologically sound meta-analysis of a promising emerging analgesic technique yielded quantitatively significant results, but the certainty of the effect was reduced by heterogeneity, small study effect, and numerous patient selection biases within each study. Interestingly, sponsored studies (17% of the 106 included) were associated with a smaller effect than those identified in the absence of industry sponsorship.
, McMaster University