The somatic and autonomic innervation of the clitoris; preliminary evidence of sexual dysfunction after minimally invasive slings.

INTRODUCTION: Vaginal sling procedures may have a negative effect on sexual function due to damage to vascular and/or neural genital structures. Even though autonomic innervation of the clitoris plays an important role in female sexual function, most studies on the neuroanatomy of the clitoris focus on the sensory function of the dorsal nerve of the clitoris (DNC). The autonomic and somatic pathways in relationship to sling surgery have up to the present not been described in detail.

AIM: The aim of this study is to reinvestigate and describe the neuroanatomy of the clitoris, both somatic and autonomic, in relation to vaginal sling procedures for stress urinary incontinence.

METHOD: Serially sectioned and histochemically stained pelves from 11 female fetuses (10-27 weeks of gestation) were studied, and three-dimensional reconstructions of the neuroanatomy of the clitoris were prepared. Fourteen adult female hemipelves were dissected, after a tension-free vaginal tape (TVT) (7) or tension-free vaginal tape-obturator (TVT-O) (7) procedure had been performed.

MAIN OUTCOME MEASURES: Three-dimensional (3-D) reconstruction and measured distance between the clitoral nerve systems and TVT/TVT-O.

RESULTS: The DNC originates from the pudendal nerve in the Alcock's canal and ascends to the clitoral bodies. In the dissected adult pelves, the distance of the TVT-O to the DNC had a mean of 9 mm. The cavernous nerves originate from the vaginal nervous plexus and travel the 5 and 7 o'clock positions along the urethra. There, the autonomic nerves were found to be pierced by the TVT needle. At the hilum of the clitoral bodies, the branches of the cavernous nerves medially pass/cross the DNC and travel further alongside it. Just before hooking over the glans of the clitoris, they merge with DNC.

CONCLUSION: The DNC is located inferior of the pubic ramus and was not disturbed during the placement of the TVT-O. However, the autonomic innervation of the vaginal wall was disrupted by the TVT procedure, which could lead to altered lubrication-swelling response.