Perineal Nerve - Podcast Version 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The perineal nerve (S2-4) is a nerve of the pelvic region and the largest terminal branch of the pudendal nerve. It supplies motor innervation to the perineal muscles as well as contributing to the sensory supply of the perineum. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Course The perineal nerve arises from the pudendal nerve within the pudendal canal – a passageway within in the lateral wall of the ischioanal fossa. After leaving the pudendal canal, the perineal nerve continues for another 2-3cm (acccompanied by the perineal artery) and then terminates by dividing into into two branches: Superficial perineal nerve – gives rise to posterior scrotal/labial sensory branches. Deep perineal nerve – supplies motor innervation to the perineal muscles and sensation to the vestibule and inferior vagina. By TeachMeSeries Ltd (2026) Fig 1The perineal nerve arises from the pudendal nerve within the pudendal canal. Pro Feature - Dissection Atlas Muscles of the female perineum Muscles of the female perineum You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Sensory Functions The perineal nerve supplies cutaneous sensation via its two main branches: Superficial perineal nerve – gives rise to posterior scrotal/labial sensory branches. In males, supplies the skin of the perineum and posterior scrotum In females, supplies the skin of the labia minora and majora Deep perineal nerve – supplies the sensation to the vestibule and inferior vagina in females. Adapted from work by Cancer Research UK [CC BY-SA 4.0] Fig 2The perineal nerve supplies sensation to the labia, vestibule and inferior vagina in females. Motor Functions The deep branch of the perineal nerve provides motor innervation to the perineal muscles: Bulbospongiosus Ischiocavernosus Superficial transverse perineal muscle External urethral sphincter Levator ani muscle Frequent questions What is the perineal nerve and its origin? The perineal nerve is the largest terminal branch of the pudendal nerve, originating from the sacral segments S2 to S4. It is responsible for motor innervation to the perineal muscles and contributes to sensory innervation in the perineal region. What are the primary functions of the perineal nerve? The perineal nerve has both motor and sensory functions. It innervates perineal muscles and provides sensory supply to the skin of the perineum, posterior scrotum in males, and labia in females. How does the perineal nerve course through the pelvic region? The perineal nerve emerges from the pudendal nerve within the pudendal canal, located in the lateral wall of the ischioanal fossa. After exiting the canal, it travels approximately 2-3 cm before branching into the superficial and deep perineal nerves. What muscles are innervated by the deep branch of the perineal nerve? The deep branch of the perineal nerve supplies motor innervation to several key muscles, including the bulbospongiosus, ischiocavernosus, superficial transverse perineal muscle, external urethral sphincter, and levator ani muscle. What sensory areas does the perineal nerve supply? The perineal nerve provides cutaneous sensation through its branches, with the superficial perineal nerve supplying the skin of the perineum and posterior scrotum in males, and the labia in females. The deep perineal nerve contributes sensory innervation to the vestibule and inferior vagina. Rate This Article