Sacral nerve neuromodulation as primary treatment for faecal incontinence with disrupted anal sphincters: medium and long-term results

Introduction The standard treatment for faecal incontinence secondary to obstetric sphincterdamage is anal sphincter repair. However, the results of this procedure deteriorate withtime. Sacral nerve stimulation (SNS) has become an established therapy for faecal incontinencein patients with intact sphincter muscles, with good medium term results. We assess themedium and long-term results of SNS as first line treatment in patients with obstetric-relatedfaecal incontinence. Methods: All patients with obstetric-related faecal incontinence anddemonstrated external and internal sphincter disruption on anal endosonography wereincluded in the study. These patients would have normally undergone anterior anal sphincterrepair. Patients underwent temporary stimulation followed by assessment at 2 weeks. Permanentstimulator was then implanted in patients with significant improvement. Post implantationpatients were followed up 1, 3, 6, 12, 36, and 48 months. Demographic, clinical, operativeand anorectal physiology data was collected prospectively. Results: 20 consecutive womenwith a median age of 42 (35-62) years completed temporary screening and 19 went on topermanent implantation. Faecal incontinence improved in all patients from Wexner scoresof median 16 (10-20) preoperatively to median 5 (1-11) at 2 weeks. There was furtherimprovement in faecal incontinence with median Wexner scores of 3, 3.5, 4, 4, 3.5 & 3 at1,3,6,12,36 & 48 months respectively (p<0.0001). The remaining patient was followedup at 2 weeks post temporary SNS and demonstrated significant improvement in faecalincontinence (Wexner score 19 pre-procedure to 3 post-procedure), but was lost to followup thereafter. There was significant improvement in general and mental health, emotionalrole, social function and vitality in all patients. There were no major complications and noimplants were removed. Conclusion: This is the first study showing long-term results ofSNS for primary treatment of faecal incontinence with damaged anal sphincter. We haveshown that sacral nerve neuromodulation is a safe and effective minimally invasive first linetreatment for such patients. The improvement in faecal incontinence achieved in short termis sustained over a follow up of 4 years