Sacral stimulation for neurogenic bladder outlet obstruction

There are four anatomical sites at which functional electrical stimulation may be applied to the sacral neural outflow to achieve voiding of urine in patients with neurogenic bladder dysfunction: the micturition centres of the conus medullaris; the sacral anterior nerve roots; the mixed sacral nerves in their intraspinal, extradural course; and the pelvic nerves. This paper reviews the surgical and physiological advantages and disadvantages of each of these stimulation sites.