Anatomical Variation of the Pudendal Nerve and Related Structures.

Background and objective: The pudendal nerve (PN) typically arises from sacral roots S2-S4 and gives rise to three main branches: inferior rectal, perineal, and dorsal genital nerves. However, conditions such as pudendal neuralgia and persistent genital arousal disorder exhibit great variability in clinical course and therapeutic responses. Anatomical variation of the PN may contribute to this variability by placing the nerve or its branches in vulnerable positions that lead to compression or traction. This scoping review examined PN anatomical variations to gain a better understanding of their role in pathophysiology and clinical outcomes. Methods: A scoping review was conducted according to the Preferred Reporting of Items for Systematic Reviews and Meta-Analyses-Extension for Scoping Reviews (PRISMA-ScR) guidelines to answer the following research question: What are the anatomical variations of the PN and related structures along its route? Searches were conducted in the MEDLINE and EMBASE databases, with manual screening. Studies on human anatomical investigations of PN variations, regardless of method, were included. Key findings and limitations: The review revealed substantial anatomical diversity in nerve roots, trunk, branches, and related structures, for which detailed schematic illustrations were developed. Limitations include methodological heterogeneity across studies, the predominance of elderly cadaver specimens, and lack of formal quality assessment. Conclusions and clinical implications: Anatomical variation is a key factor in the development and persistence of PN-related conditions. An understanding of this variability is critical for diagnosis, surgical planning, and effective management. This review challenges assumptions of "typical anatomy" and offers context for refinement of decompression techniques and therapeutic strategies. Patient summary: Our study shows that one of the nerves in the pelvis, called the pudendal nerve, varies between individuals. This could explain why standard treatments do not work in some patients and could help doctors to better understand these conditions.