Effectiveness of percutaneous tibial nerve stimulation in managing refractory constipation

Aim Chronic constipation can be aetiopathogenically classified in to slow transit constipation (STC), rectal evacuation difficulty (RED) or a combination (BOTH). Although the efficacy of percutaneous tibial nerve stimulation (PTNS) in faecal incontinence has been well proven, a current literature search identifies only one study which assessed its effect on constipation. We aimed to evaluate the effectiveness of PTNS in patients with different causes of constipation. Method 34 patients (30 women, median age 50 (20-79) years with constipation who had previously failed maximal laxative and biofeedback therapy participated in the study. All patients underwent a baseline radio-opaque marker transit study and anorectal physiology. All had 12 sessions of PTNS of 30 minutes per session. A fall in the Wexner constipation score to ≤15 or by ≥5 points was taken as the primary outcome. Secondary outcomes included the results of pre- and post- PTNS transit and anorectal physiology studies. Results There were patients with 11 STC, 14 with RED and 9 with BOTH. A response was seen in four patients (1/11 STC, 2/14 RED and 1/9 BOTH). Comparing pre- and post- PTNS, there was no significant change in the mean Wexner score (p = 0.10). There was no change in colonic transit time among the whole population (p = 0.56) or among those with STC (p=0.47). There was no improvement in balloon expulsion in the whole group (p=0.73) or in patients with RED (p=0.69). Conclusion Percutaneous tibial nerve stimulation is of no benefit to patients with constipation, whatever aetiopathogenic mechanism is responsible for the symptoms. This article is protected by copyright. All rights reserved.