ABSTRACT
Introduction: Management of intractable Functional Constipation (FC) can include antegrade enemas, transanal irrigation and in some cases sacral nerve stimulation (SNS). SNS is expensive, invasive and not available in all centers. Although the mechanism of action of SNS in the treatment of FC is unclear, one of its effects is through direct modulation of nerve activity. Percutaneous tibial nerve stimulation (PTNS) allows transmission of electronic impulses and retrograde stimulation to the sacral nerve plexus in a simple and non-invasive fashion. Methods: Single-center, prospective interventional study. Children between the ages of 4-14 with Rome IV diagnosis of FC. Exclusion criteria: Neurological problems or organic causes of fecal or urinary incontinence. Over a 2-week period, children received 10 daily sessions of PTNS (30 min/day) during weekdays. Electrodes were placed over the skin of the ankle posteriorly. Placement of electrodes on the anatomic route of the posterior tibial nerve was confirmed through visualization of rhythmic flexion of toes during initial stimulation. Strength of the stimulus was below pain threshold. Children recorded characteristics of bowel movements (BMs) daily during the intervention and the following 7 days. Consistency was assessed through Bristol scale and quality of life (QOL) via PedsQL GI questionnaire. Results: 23 children were enrolled. One child was excluded for acute gastroenteritis (on the 7th session of PTNS) and one child for COVID-19 exposure. 20 patients completed the study (4-14 years) (8,4+/-3,2years, 71.4 % female) day 1 (n=21) to day 17(n=20). By the end of the trial, there was a significant improvement in consistency of BMs, fecal incontinence (FI) (no episodes of FI), presence and intensity of abdominal pain and a trend for improvement in blood in the stools (no children had blood in the stools) (Table 1). In PedsQL GI questionnaire, there was a 91.3% improvement of incomplete BM and 86.3% improvement in abdominal pain. Only one child required rescue therapy (no BM for 3 days). This child was the only treatment failure. Two children reported leg cramps that resolved by changing the side of PTNS application. At 7 days follow-up, there was persistently significant improvement in presence and intensity of abdominal pain and no children had FI or blood in the stools. Conclusion We found an improvement in stool consistency, FI, blood in stools and QOL at the end of the trial with sustained benefits in abdominal pain, blood in stools and FI at follow-up. The study suggests that PTNS may be a promising noninvasive treatment for FC in children. Larger studies with long-term follow-up should confirm our findings. Controlled randomized clinical trials with various protocols are recommended. (Table Presented)