I have obtained the full paper Am J Obstet Gynecol. 2015 Jun Anatomic variations of pudendal nerve within pelvis and pudendal canal: clinical applications, by Pedro A. Maldonado, MD; Kathleen Chin, MD; Alyson A. Garcia, MD; Marlene M. Corton, MD, MSCS,
The paper, coming out of the respected University of Texas OB/GYN department, is a study of 13 normal female cadavers. The pudendal nerve was found to be routinely "entrapped", to the point where the authors suggest that there is no such thing as pudendal nerve entrapment, and that attachments ("entrapments") are normal. This is an extract from the commentary section at the end:
This excellent study throws profound doubt on the whole field of PN surgery. Note that surgeons who perform PNE surgery claim that the pudendal nerve should "glide freely". The above study clearly shows that this is not the case in most people, thus undermining the basis of the theory of pudendal nerve entrapment.An interesting finding of this study was the fixation of the pudendal nerve (PN) on the dorsal surface of the sacrospinous ligament (SSL). These connective tissue attachments were found not only on the dorsal surface of the SSL-ischial spine junction but within the pudendal canal. Whereas previous authors have noted that the PN is surrounded by a connective tissue sheath in the pudendal canal,(4,9) we found no specific descriptions or assessments of the mobility or connective tissue interactions of the PN on the dorsal surface of the SSL. This finding has potential implications in the surgical treatment of pudendal neuralgia, and it may be misleading to attribute pudendal neuralgia to nerve entrapment. Thus, procedures seeking to decompress the PN may not address the true etiology. In fact, these procedures may potentially result in significant complications, given the complexity of surrounding nerve and vascular anatomy
For me, one of the most interesting things about this study, other than the fact that all pudendal nerves are attached by connective tissue to multiple sites, is the complexity of the region in which the PNE surgeons operate. It's a minefield I would not want any old surgeon messing about there, truly. This is not a simple operation; don't ever let anyone tell you that it is. Moreover, the cadavers show the wide variability of the nerve and its multiple trunks and diverse branching patterns. We all have pudendal nerves that are slightly differently located and which branch in different places, making any operation on this nerve fraught with difficulty. The nerve is only about 4.5mm wide, hidden away in a mass of muscle, sinew and connective tissue.
Here is a photo of how the pudendal nerve is connected ("entrapped") by connective tissue in normal people:
The study ends with these wise words of warning:
I will make the full paper available to all members soon, depending on interest.As health care providers, we should carefully weigh the risks and benefits of interventional procedures with limited clinical efficacy and potential for significant complications. A comprehensive knowledge of the complex pudendal nerve anatomy is essential in optimizing diagnostic and treatment modalities.