World J Urol (1991) 9:126-132 World Journal of ]~ Urology © Springer-Verlag 1991 Intradural sacral rhizotomies and implantation of an anterior sacral root stimulator in the treatment of neurogenic bladder dysfunction after spinal cord injury Surgical technique and complications Ph. E.V. Van Kerrebroeck*, E. Koldewijn, H. Wijkstra, and E M. J. Debruyne Department of Urology, Unit for Neuro-Urology and Urodynamics, University Hospital St. Radboud, NL-6500 HB Nijmegen, The Netherlands Summary. Hyperreflexia of the detrusor is an important problem in the treatment of dysfunction of the lower uri- nary tract after spinal cord injury. Many treatment mo- dalities have been proposed but they mostly give only temporary relief or are accompanied by severe side ef- fects. In 1969, Brindley started animal experiments to ac- complish intradural electrical stimulation of the sacral roots. A serially produced intradural sacral root stimula- tor that has been available since 1986 enables elec- trostimulation of the appropriate sacral roots that is suf- ficient to induce bladder emptying. The combination of the implantation of this stimulator with a complete in- tradural sacral posterior rhizotomy from $2 to $4/$5 ap- pears to be an interesting treatment modality for the hyperreflexic bladder after spinal cord injury. The surgi- cal technique is described, as are the postoperative care and the possible complications. A spinal cord lesion above the sacral micturition center in the conus medullaris results in a reflex (or spastic) bladder after the initial phase of spinal shock. This reflex activity of the detrusor is the result of the separation of the bladder segmental reflexes from the higher cortico- spinal control [12]. Micturition can be induced by exter- nal triggering, but the quality is inferior as compared with normal urination. Externally triggered micturition often results in high levels of residual urine, is unpredict- able and produces high intravesical pressure due to unco- ordinated sphincter behaviour and augmented outflow resistance. In some cases it is difficult to trigger the blad- der artificially, and the occurrence of uncontrolled and uncoordinated contractions between the episodes of mic- turition are responsible for periods of severe incontinence in many patients. Residual urine can cause urinary tract * To whom correspondence should be addressed at: Department of Urology, University Hospital St. Radboud, Geert Grooteplein Zuid, 16, P.B. 9101, NL-6500 HB Nijmegen, The Netherlands infections, and the high intravesical pressure can provoke vesico-ureteral reflux and, eventually, pyelonephritis that can result in hydronephrosis and deterioration of renal function [11]. In some patients the detrusor-sphincter dyssynergia causes detrusor hypertrophy, which can also result in hydronephrosis and bladder decompensation [20]. Therefore, one of the most important goals in the neuro-urological treatment of patients presenting with a spinal cord injury must be the relief of bladder spasticity to restore the reservoir function. Incontinence treatment and controlled micturition also contribute to the quality of life and aid in the rehabilitation of the patient. Since many years or so, several treatment modalities have been proposed for the control of reflex activity so as to overcome the considerable morbidity of the spastic bladder and to cure incontinence. Different bladder denervation procedures have been proposed, including selective sacral rhizotomies [23]. However, although all of these techniques initially relieve the spasticity, there is a high rate of recurrence [24]. Modern pharmacological treatment enables good bladder control but often results in large amounts of residual urine or in retention, either of which necessitates intermittent catheterisation [27]. Even following treatment with high doses of parasympa- thicolytics, which usually produce severe side effects, continence at higher bladder capacities (> 300 cm 3) can- not be guaranteed. Different forms of cystoplasty have been applied in neurogenic bladder dysfunction [1]. Us- ing these techniques, a low-pressure reservoir can be cre- ated, but the high incidence of infections, the need for catheterisation and the possible malignant degeneration require the careful selection of potential candidates. In 1969, Brindley began performing experiments in baboons to accomplish intradural electrical stimulation of the sacral roots [2]. In 1972, this resulted in implant- driven micturition in normal and paraplegic baboons fol- lowing the separation of anterior from posterior roots and subsequent stimulation of the anterior roots [3]. In 1978 the first intradural sacral root stimulator was im- planted in a patient [6], and in 1986 a report was pub- lished on the first 50 persons to receive an intradural im-