Regional anesthesia guided by ultrasound in the pudendal nerve territory

Introduction Pudendal nerve blocks have a wide range of clinical applications for the management of acute post-operative pain in urologic and gynaecologic surgery, in coloproctology, as well as in pain medicine for differential diagnosis, and for the management of pudendal neuropathies. However, despite its benefits, it is infrequently used. Objective To perform a detailed description of the most recent ultrasound-guided techniques with the aim of encouraging safe and reproducible learning. Materials and methods We have performed a broad, non-systematic review of the literature through Medline, Embase and Science Direct between 1985 and 2016, to evaluate the most relevant articles, using the following key words: pudendal nerve anatomy; pudendal nerve; pudendal nerve blocks; pudendal nerve ultrasound; pudendal neuralgia; nerve entrapment; chronic pain; Alcock canal; and pelvic pain. The search was limited to articles published in Spanish; English and French. Results Recent descriptions were found of a large number of anatomic variants, which are described in detail and shown in graphic documents in order to facilitate the sonoanatomic correlation of nerve location as a guide for the performance of the pudendal nerve block through the different approaches. Conclusions The deep and detailed knowledge of the anatomy of the pudendal nerve and its variations is essential for the realization of Regional Anesthesia techniques guided by images. These promising techniques should continue to be evaluated with clinical studies.