The influence of sacral nerve stimulation on anorectal dysfunction.

Aim: Sacral nerve stimulation (SNS) has become an established option in the management of defaecatory disorders. There are many data on the end-organ effects of SNS, but limited consensus on its mechanism of action. The objective of this review was to determine the effect of sacral nerve stimulation (SNS) on anorectal function.
Method: Systematic literature review of the effect of sacral nerve stimulation (SNS) on anorectal function.
Results: There was significant heterogeneity of data pertaining to the effects of SNS on anorectal function, with no consistent change in physiological measures identified. Most data supported a mixed mechanism of action on anal motor and rectal sensory functioning.
Conclusion: To date, conflicting data exist on the mechanism of action of SNS as determined by end-organ changes in anorectal physiology. Nevertheless, the data as they stand best support a mixed mechanism of action on anal motor and rectal sensory functions.
(© 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.)