title: Sacral neuromodulation for faecal incontinence following obstetric sphincter injury - outcome of percutaneous nerve evaluation.
abstract: OBJECTIVE
  The purpose of this study was to assess the efficacy of percutaneous nerve evaluation (PNE) in women with faecal incontinence (FI) following obstetric anal sphincter injury and to relate the outcomes to baseline factors, with special emphasis on the extent of the sphincter defect.
  
  
  METHODS
  This was a prospective study at a tertiary colorectal referral unit at the University Hospital of North Norway conducted from 2012 to 2014. Sixty-three women underwent a 3-week PNE using a tined lead and the Verify®external neurostimulator. The primary outcome was efficacy, defined as the percentage reduction in weekly FI episodes, and patients with a reduction of 50% or more were defined as responders. Baseline factors affecting the primary outcome were explored. Sphincter defects were classified with a validated three-dimensional endoanal ultrasound defect score.
  
  
  RESULTS
  Fifty-six (89%) of the 63 women were responders with a reduction in weekly FI episodes of 94.5%, from a median (interquartile range) of 4.8 (2.0-11.0) to 0.5 (0-2.0) (P < 0.001). Twenty-nine (52%) reported no weekly FI episodes, and urgency episodes disappeared in 18 (32%). In the multivariable linear regression model, efficacy was related to concomitant urinary incontinence (P = 0.04), body mass index (BMI) (P = 0.03) and pain during PNE (P = 0.046) but not to the extent of the sphincter defect (P = 0.1). Responders had a higher St Mark's score than nonresponders (P = 0.046).
  
  
  CONCLUSIONS
  The vast majority of women had successful PNE tests. Responders had higher baseline St Mark's scores than nonresponders. Efficacy was related to concomitant urinary incontinence, BMI and pain, not to the extent of the sphincter defect.
authors.affiliation: Department of Gastroenterological Surgery, University Hospital of North Norway, Tromsoe, Norway.
authors.forename: M B
authors.initials: MB
authors.lastname: Rydningen
authors.affiliation: Department of Gastroenterological Surgery, University Hospital of North Norway, Tromsoe, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Dehli
authors.affiliation: Department of Community Medicine, The Arctic University of Norway, Tromsoe, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Wilsgaard
authors.affiliation: Department of Gastroenterological Surgery, University Hospital of North Norway, Tromsoe, Norway.|Institute of Clinical Medicine, The Arctic University of Norway, Tromsoe, Norway.
authors.forename: R O
authors.initials: RO
authors.lastname: Lindsetmo
authors.affiliation: Department of Radiology, University Hospital of North Norway, Tromsoe, Norway.|Narvik University College, Narvik, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Kumle
authors.affiliation: National Advisory Board of Continence and Pelvic Floor Health of Norway, University Hospital of North Norway, Tromsoe, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Stedenfeldt
authors.affiliation: Department of Gastroenterological Surgery, University Hospital of North Norway, Tromsoe, Norway.|Institute of Clinical Medicine, The Arctic University of Norway, Tromsoe, Norway.|National Advisory Board of Continence and Pelvic Floor Health of Norway, University Hospital of North Norway, Tromsoe, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Norderval
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000000981:diagnostic imaging / Q000293:injuries*; D036861:Delivery, Obstetric / Q000009:adverse effects*; D004599:Electric Stimulation Therapy; D019160:Endosonography; D005242:Fecal Incontinence / Q000209:etiology / Q000628:therapy*; D005260:Female; D006801:Humans; D016014:Linear Models; D008160:Lumbosacral Plexus; D008875:Middle Aged; D015999:Multivariate Analysis; D009664:Norway; D011446:Prospective Studies; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000209:etiology
keywords: BMI; Faecal incontinence; OASIS; PNE; sacral neuromodulation; urinary incontinence