Permanent sacral nerve modulation for fecal incontinence and associated urinary disturbances

Sacral nerve modulation (SNM) using an implantable pulse generator is gaining increasing acceptance in the treatment of several functional disturbances of the urinary and intestinal tract. This new therapeutic approach offers new possibilities in the treatment of fecal incontinence (FI) by means of its possible effects on anorectal physiology.

Fourteen patients with FI, six of whom had associated urinary disturbances, underwent permanent SNM after successful peripheral nerve evaluation tests. All had a clinical evaluation including FI grading systems (American Medical systems, AMS; Continence Grading System, CGS) and quality of life questionnaires (Fecal Incontinence Quality of Life, FIQL), and anorectal physiology tests performed before and during electrostimulation. Two patients had a lead displacement which was repositioned. Median follow-up was 14 months (range 6-48 months).

AMS scores decreased significantly from 101 to 67 after 24 months CGS scores from 15 to 2 after 2 months. The median number of episodes of major incontinence per 2 weeks decreased from 14 to 1 after 24 months. FIQL scores improved significantly in the nine patients tested from an overall score of 1.59 to 3.3, with improvement in all areas of the FIQL. Four of the six patients with associated urinary disturbances had a significant improvement in their symptoms. Anal resting and squeezing tone did not change significantly, nor did rectal volumetry, compliance, rectoanal inhibitory reflex, or length of the anal high-pressure zone, while 24-h rectal manometry showed inhibition of the spontaneous rectal motility complexes after meal and on awakening in the only two patients undergoing this investigation.

Although the mechanism of action of SMN is still unclear and requires further investigations, clinical results are very encouraging, confirming the role of this new and safe procedure in the treatment of FI and associated urinary disturbances.