Tethered spinal cord: the effect of neurosurgery on the lower urinary tract and male sexual function.

OBJECTIVE

To determine the effect of neurosurgical untethering on the lower urinary tract and male sexual function, in patients with tethered spinal cord.

PATIENTS AND METHODS

Thirty-six children with tethered spinal cord due to neurospinal dysraphism were assessed clinically and urodynamically before and after surgical untethering. Sexual function was evaluated in 14 boys before and after neurosurgery. In young boys, the assessment was by parental observation and was considered normal if erections had been observed regularly, or if the child had mentioned having an erection at any time. Older patients were asked if they had achieved voluntary erections and whether or not they were able to ejaculate.

RESULTS

The mean follow-up was 91 months and the mean follow-up after neurosurgery was 34 months. A lasting improvement of urinary tract function occurred in only one patient, while another became worse. Seven children had temporary changes of bladder/sphincter function; two developed detrusor overactivity with sphincter dyssynergia and five had signs of bladder denervation. Long-term follow-up showed no permanent changes of lower urinary tract function in 94% of 34 patients. Sexual function was considered normal in 13 boys. One boy apparently gradually lost erectile ability before untethering and regained it after surgery, while another boy had erectile dysfunction post-operatively for almost 6 months.

CONCLUSION

Changes in bladder-sphincter function after untethering are usually transient and often the result of partial denervation. Although a small group of children seem to benefit from untethering, others can become worse and the individual outcome cannot be predicted. Erectile dysfunction can occur and parents and patients have to be informed of this possible complication. As pre-operative progression of neurological symptoms and post-operative denervation were observed only in patients with myelomeningocele and lipomyelomeningocele, this group may be distinct from patients with occult forms of spinal dysraphism. The natural history in the latter group of patients is unclear and a beneficial effect of prophylactic untethering remains to be proven by controlled prospective studies.