Ramification of the dorsal clitoral nerve along its course on the human clitoris

The detailed anatomy of the human bulboclitoral organ remains, despite recent efforts of morphological disciplines, a largely unstudied area. In particular, to understand the functional role of the clitoris it requires detailed anatomical studies of the nervous structures supplying the organ, especially the dorsal clitoral nerve. Although there are rough descriptions of this nerve, there is little reliable information about its exact ramification and where and how many branches leave or enter the main trunk. This knowledge is essential in this era of highly specialized microsurgery and will help to understand clitoral physiology and to design novel surgical techniques to restore clitoral function.

We examined n = 9 human clitoris specimens from fresh body donors (age range: 64-90 years). These were harvested in an unfixed state, afterwards formaldehyde-fixed, and made transparent as macroscopic specimens using modified Sihler staining. The course and ramification of the stained nerve fascicles could be determined during diaphanoscopic microdissection with the help of a macroscope.

As result of the study, two ramification hotspots were determined. The first hotspot shows an average of 1.8 fascicles separate within the clitoral suspensory ligament, with 67% belonging to the ascending and 33% to the prepubic segment of the dorsal clitoral nerve. More distally and based on the information as to whether the glans and prepuce are innervated by medial or lateral fascicles, a classification (types I-IV) of the ramification possibilities as a second hotspot has been established. Furthermore, it has been found that clitoral innervation is not bilaterally symmetrical and that there is a nerve-free area ventral to the glans.

In addition to a general understanding of the course of the dorsal clitoral nerve, the knowledge gained also serves as a basis for the development of new and the improvement of established surgical techniques for the reconstruction of clitoral function after pathological changes or defective interventions (e.g., female genital mutilation/cutting).