Randomized clinical trial of sacral versus percutaneous tibial nerve stimulation in patients with faecal incontinence

BACKGROUND: Sacral nerve stimulation (SNS) is a well established therapy for faecal incontinence (FI). Percutaneous tibial nerve stimulation (PTNS) is a newer, less invasive, treatment. The effectiveness and acceptability of these treatments have not been compared systematically. METHODS: An investigator-blinded randomized pilot trial of PTNS versus SNS with a parallel qualitative study was performed. Quantitative clinical outcomes and qualitative data from patient interviews were collected for both interventions. RESULTS: Forty patients (39 women; mean age 59 years) met the eligibility criteria; 23 were randomized to receive SNS and 17 to PTNS. Fifteen patients progressed to permanent SNS implantation and 16 received a full course of PTNS. Within-group effect sizes were marginally greater for SNS than for PTNS on available-case analysis. Mean(s.d.) FI episodes per week at baseline, and 3 and 6 months of follow-up were: 11·4(12·0), 4·0(4·0) and 4·9(6·9) respectively for SNS compared with 10·6(11·2), 5·8(6·9) and 6·3(6·9) for PTNS. Mean(s.d.) Cleveland Clinic Incontinence Score values at baseline, and 3 and 6 months were: 16·2(3·0), 11·1(5·2) and 10·4(5·6) for SNS versus 15·1(2·7), 11·7(4·4) and 12·1(5·2) for PTNS. Improvement of at least 50 per cent in FI episodes per week at 6 months was seen in 11 of 18 patients in the SNS group compared with seven of 15 in the PTNS group. Effect estimates for SNS with chronic implanted stimulation were larger (10 of 15 patients at 6 months). Disease-specific and generic quality-of-life improvements complemented clinical outcome data. Qualitative analysis of interview data suggested that both treatments had high acceptability amongst patients. CONCLUSION: In the short term, both SNS and PTNS provide some clinical benefit to patients with FI. Registration numbers: 2010-018728-15 and 10479 (http://public.ukcrn.org.uk/search/StudyDetail.aspx?StudyID=10479).