title: Effects of a magnetic field on pelvic floor muscle function in women with stress urinary incontinence.
abstract: BACKGROUND
  Magnetic fields have been found to affect neuromuscular function.
  
  
  OBJECTIVE
  To study the effect of a magnetic field on measurements of urethral function in women with stress urinary incontinence.
  
  
  METHODS
  Observational comparative study.
  
  
  METHODS
  Consecutive patients in a continence center.
  
  
  METHODS
  Twenty-six consecutive women with diagnosis of stress urinary incontinence (SUI).
  
  
  RESULTS
  History and physical examination, neurologic exam, urethrocystoscopy, urodynamic testing with water-filling cystometry, urethral profilometry at rest, during coughing, and during coughing while performing a levator ani contraction (knack maneuver).
  
  
  METHODS
  The same urodynamic procedures were performed again after the subjects were asked to step on specifically designed magnets (magnetic cushion device).
  
  
  METHODS
  Two-tailed student t test.
  
  
  METHODS
  Urethral pressure at rest, during coughing, and during coughing while performing a levator ani contraction.
  
  
  RESULTS
  Mean age was 58.3 years (range: 36-81), mean parity 2.8 (range: 0-8). The urodynamic parameters measured without and with the use of the magnetic cushion device were not found to be different except for the knack maneuver. The pressure in the urethra during the knack maneuver while the subjects were stepping on the magnetic device was significantly higher than the 1 obtained without the magnetic field.
  
  
  CONCLUSIONS
  In our patient population, a magnetic field increases the efficacy of voluntary levator ani contractions.
authors.affiliation: University of California, Los Angeles David Geffen School of Medicine, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Bergman
authors.forename: Jack R
authors.initials: JR
authors.lastname: Robertson
authors.forename: Giovanni
authors.initials: G
authors.lastname: Elia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California; D005260:Female; D006801:Humans; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000294:innervation; D017773:Pelvic Floor / Q000503:physiopathology*; D013997:Time Factors; D014521:Urethra / Q000503:physiopathology*; D014550:Urinary Incontinence, Stress / Q000175:diagnosis / Q000503:physiopathology; D014563:Urodynamics