Surface and boney landmarks for sacral neuromodulation: a cadaveric study.

Introduction And Hypothesis: Standard external landmarks have been suggested as a guide for in-office percutaneous nerve evaluation (PNE), but validity of these landmarks has not been assessed. Our objective was to determine whether the standard 9 cm from the tip of the coccyx indicates the position of the S3 sacral foramen and whether other boney landmarks and measurements improved positioning.

Methods: Measurements and distances between external boney landmarks were obtained in 22 embalmed cadavers.