Anatomic relationships of the pudendal nerve branches

Objective: We sought to characterize the distribution of the pudendal nerve branches and to correlate findings with injury risk related to common midurethral sling procedures. Study Design: Dissections were performed in 18 female cadavers. Biopsies were obtained to confirm gross findings by histology. Results: In all dissections, most of the clitoral and perineal nerves coursed caudal to the ventral portion of the perineal membrane. The inferior rectal nerve did not enter the pudendal canal in 44% (n = 8) of specimens. Nerve tissue was confirmed histologically in tissue sampled. Conclusion: The clitoral and perineal branches of the pudendal nerve should be at low risk of direct nerve injury during midurethral slings and similar procedures as they course caudal to the ventral portion of the perineal membrane. The inferior rectal nerve might be at risk of injury during procedures that involve passage of needles through the ischioanal fossa.