title: Sacral nerve stimulation.
abstract: BACKGROUND
  Sacral nerve stimulation implies electrical stimulation of a sacral nerve root by an electrode and a pacemaker. Within the past few years, sacral nerve stimulation has become a possible treatment option for selected patients with urinary retention, urinary incontinence, anal incontinence and constipation. The method is furthermore being tested for several other conditions.
  
  
  METHODS
  The article presents the method and treatment results following various indications based on the authors' own experience and non-systematic PubMed search.
  
  
  RESULTS
  During a test period an external pacemaker is used for 3-30 days, with length of test differing according to the indication. A positive test (improvement of symptoms by 50 % or more) is achieved by 70-90 % of patients with anal incontinence, 70 % with urinary non-obstructive retention, 52-77 % with urinary urge incontinence and 43-72 % with constipation. Sacral nerve stimulation may also be effective in patients with chronic pelvic pain. Following implantation of a pacemaker a sustainable effect is seen in 50-90 % of patients with a positive test. Up to 75 % of patients will need repeated follow-up including pacemaker reprogramming or reoperations due to diminished effect. The longevity of the pacemaker is 3-10 years, and it must be replaced operatively when the battery has depleted.
  
  
  CONCLUSIONS
  Treatment with sacral nerve stimulation may be efficient over time in patients with various pelvic floor dysfunctions, especially anal incontinence and non-obstructive urinary retention. Most of the patients will need close follow-up in order to maintain an optimal result.
authors.affiliation: Department of Gastroenterological Surgery andNorwegian Continence and Pelvic Floor Centre, University Hospital of North Norway, Norway. stig.norderval@unn.no
authors.forename: Stig
authors.initials: S
authors.lastname: Norderval
authors.forename: Mona
authors.initials: M
authors.lastname: Rydningen
authors.forename: Rolv-Ole
authors.initials: RO
authors.lastname: Lindsetmo
authors.forename: Dag
authors.initials: D
authors.lastname: Lein
authors.forename: Barthold
authors.initials: B
authors.lastname: Vonen
mesh_terms: D003248:Constipation / Q000628:therapy; D004599:Electric Stimulation Therapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D005242:Fecal Incontinence / Q000628:therapy; D005500:Follow-Up Studies; D006801:Humans; D058542:Implantable Neurostimulators; D008160:Lumbosacral Plexus / Q000502:physiology; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000628:therapy; D016055:Urinary Retention / Q000628:therapy