Effects of Posterior Tibial Nerve Stimulation on Fecal Incontinence: An Umbrella Review.

Purpose: This study aimed to summarize relevant data from previous systematic reviews (SRs) and conduct comprehensive research on the clinical effects of posterior tibial nerve stimulation (PTNS), via the transcutaneous posterior tibial nerve stimulation (TPTNS) or percutaneous posterior tibial nerve stimulation (PPTNS) method on fecal incontinence (FI).

Materials And Methods: In adherence to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic search was conducted on PubMed, Embase, Scopus, and Web of Science databases. We included English-language, full-text SRs reporting outcomes for FI following either PPTNS or TPTNS. The quality of included studies was assessed using the Joanna Briggs Institute checklist. In addition, reanalyzing the meta-analyses was conducted using Comprehensive Meta-Analysis (CMA) software version 3.0 to achieve effect sizes and the level of statistical significance was set at p ≤ 0.05.

Results: From a total of 835 citations, 14 SRs met our inclusion criteria. Four of these also conducted a meta-analysis. Most SRs reported an overall improvement in different study parameters, including bowel habits and quality of life. However, there were major inconsistencies across the results. The most studied outcome was FI episodes, followed by incontinence score. The summary outcomes showed no statistically significant changes in comparing PTNS with sham or sacral nerve stimulation (SNS) for FI (p > 0.05). However, the results of subgroup analysis based on the type of intervention in the control group revealed that FI episodes were significantly fewer than in the PTNS arm, whereas PTNS led to fewer episodes of FI than did the sham. In terms of incontinence score, the results showed that PTNS compared with sham did not change the incontinence score; however, SNS improved the score significantly in one eligible study for reanalysis when compared with PTNS (p < 0.001).

Conclusions: The findings of the current umbrella review suggest that PTNS can potentially benefit patients with FI. However, this is concluded from studies with a limited population, disregarding the etiology of FI and with limited follow-up duration. Therefore, caution must be taken in contemplating the results.