Electrical stimulation in the treatment of faecal incontinence.

Abstract

Background There is a delay between obstetric injury and the onset of faecal incontinence (FI) for most females, yet traditional surgical management has focussed on the obstetric injury when treating FI. Recently, electrical stimulation has been used in a number of treatments however the modes of action and efficacies are unknown. This study aimed to assess the aetiology of FI, while exploring the efficacy of the three main modalities of electrical stimulation for FI, namely sacral nerve stimulation (SNS), percutaneous tibial nerve stimulation (PTNS) and electrically stimulated gracilis neosphincter (ESGN). Methods Data was analysed for 999 females, who had undergone anorectal physiology testing (ARP) excluding confounding factors other than aging and childbirth. Patients treated for FI with PTNS or SNS were investigated with ARP to assess their efficacy and any potential indicators of success. Patients with ESGN were evaluated to assess efficacy in the short, mid and long term. Results The function of the external anal sphincter is affected by childbirth, while the internal anal sphincter deteriorates with age. SNS can be effective in the treatment of FI, but only 26% of patients experience a resolution of symptoms with 74% remaining incontinent. PTNS performs slightly better with 32% of patients experiencing apparent continence; however this is significantly cheaper and less invasive than SNS. Outcome for ESGN also revealed a high failure rate, yet in the long term, this outperforms SNS and PTNS with 43% of patients being successfully treated. Discussion Both aging and childbirth contribute via different mechanisms to produce decreased anal sphincteric function. Symptomatic patients can be treated with electrical stimulation therapies however, a high failure rate is noted for all modalities. A treatment “ladder” is emerging, starting with minimally invasive PTNS, through SNS and finally the costly and demanding ESGN for highly motivated patients.