4 – The innervation of the superficial pelvic floor

The superficial pelvic floor is innervated by the three pudendal nerve branches: The dorsal nerve of the penis or clitoris, the perineal nerve (synonym: the posterior scrotal nerve (or posterior labial nerve), and the inferior rectal nerve (synonym: inferior haemorhoidal nerve).

The dorsal nerve of the penis (or clitoris) is the terminal and the deepest branch of the pudendal nerve. It innervates the skin of the shaft of the penis in males and the clitoris in females.

The perineal nerve is the other terminal branch of the pudendal nerve. In males it innervates the posterior part of the skin of the scrotum. In females it innervates the posterior part of the labia and the vaginal vestibule.

The inferior rectal nerve is a branch from the perineal nerve (or directly from the pudendal nerve). It innervates the anal canal, the external anal sphincter muscle, the muscles of the superficial pelvic floor, and the puborectalis part of the levator ani muscle.