Introduction and objective:

Overactive bladder syndrome is associated with motor disorders, such as hypertonic pelvic floor. The aim of the present study was to demonstrate the characteristics of pelvic floor muscle surface electromyography (SEMG) in patients with overactive bladder treated with percutaneous tibial nerve stimulation (PTNS).

Materials and methods:

A prospective, observational, controlled study was conducted. Seventeen patients with treatment-refractory overactive bladder volunteered to undergo pelvic floor muscle SEMG before, during, and 72 hours after treatment with PTNS. The study volunteers were divided into 2 groups: 14 in the PTNS group and 3 in the placebo group. The inclusion criteria were overactive bladder progression of at least 6 months, urinary frequency of 8 or more daily episodes, and no medication use. The exclusion criteria were positive urine or semen cultures, lithiasis, biopsy and/or pelvic organ surgery, pelvic cancer, and central nervous system lesions. The variables were analyzed using the anova and the Tukey post-hoc test, with a 95% ci. The SPSS version 10.1. software was employed.

Results:

Mean patient age was 34.23±12.90 years and mean progression time was 19.58±12.08 months, with no statistically significant difference between groups. There were significant differences in the PTNS group in the mean average SEMG (AVg SEMG) in relation to prePTNS vs intraPTNS (0.125 µV) and prePTNS vs the 72-hour postPTNS (0.171 µV) (p<0.05), whereas the differences in the mean AVg SEMGS of 0.013 µV and 0.006 µV in the placebo group were not statistically significant (p>0.05).

Conclusion:

The immediate change in the pelvic floor muscles that lasts up to 72 hours after PTNS is a possible mechanism of action of the neuroplasticity resulting from tibial nerve neuromodulation