The anatomy of midurethral slings and dynamics of neurovascular injury

The aim of this study was to investigate the course of midurethral slings using tension-free vaginal tape. The TVT procedure was performed on six fresh pelves, measurements were obtained, and the structures were cross-referenced in 16 embalmed pelves. The midurethral sling enters the suburethral tissue 2.2–3 cm caudad to the internal urethral meatus, pierces the paraurethral musculature and vascular plexus, and exits 2±0.5 cm from the midline lateral to the point of insertion of the arcus tendineus fasciae pelvis. On the pubic tubercle the sling is 4±0.5 cm, 4±1 cm and 6±1 cm from the accessory obturator, the inferior epigastric and the external iliac vessels, respectively. The critical angle of error resulting in the external iliac vessel injury is 7–15°. A current knowledge of pelvic anatomy may help the surgeon avoid the neural and vascular structures that are in the path of the sling.Editorial Comment: The authors are to be commended for the completion of a detailed observational study further investigating the course of the TVT tunneler during placement of the sling material. An unpublished study reported by Walters et al. found similar relationships between the TVT tunneler and the surrounding pelvic vasculature. Both of these studies highlight the importance of avoiding excessive lateral deviation or rotation of the TVT tunneler during placement.The conceptualization of a dynamic pelvic anatomy in relation to the advancing tip of a midurethral sling trocar is advocated to lessen intraoperative complications.S. Abbas Shobeiri can also be reached at