Deep branch of the perineal nerve

Deep branch of the perineal nerve is a significant nerve in the human body, primarily involved in the innervation of the perineum. It is a branch of the pudendal nerve, which is itself a branch of the sacral plexus, originating from spinal nerves S2-S4. The deep branch of the perineal nerve plays a crucial role in the sensory and motor innervation of the urogenital diaphragm and associated structures.

Anatomy

The deep branch of the perineal nerve diverges from the pudendal nerve in the region of the ischial spine. It travels through the Alcock's canal, a passage in the obturator fascia, before entering the deep perineal space. Within this space, it supplies motor innervation to the muscles of the urogenital diaphragm, including the deep transverse perineal muscle, the sphincter muscles of the urethra and the external anal sphincter. Additionally, it provides sensory innervation to the anterior part of the perineal skin and the skin of the scrotum or labia majora.

Function

The primary function of the deep branch of the perineal nerve is to control the muscular contractions in the perineal region, which includes the pelvic floor muscles. These muscles play a vital role in urinary and fecal continence, as well as in sexual function. The nerve's sensory fibers are responsible for conveying sensation from the perineal area to the central nervous system, allowing for the perception of touch, temperature, and pain.

Clinical Significance

Damage or injury to the deep branch of the perineal nerve can lead to various disorders, including perineal pain, erectile dysfunction, and difficulties in urination or defecation due to impaired muscle control. Causes of injury to this nerve may include childbirth, pelvic surgery, or trauma to the perineal area. Diagnosis of deep branch perineal nerve injury involves a combination of clinical examination, patient history, and sometimes nerve conduction studies. Treatment options vary depending on the cause and severity of the injury but may include physical therapy, pain management strategies, and in some cases, surgical intervention.

See Also

• Pudendal nerve
• Sacral plexus
• Perineum
• Urogenital diaphragm
• Pelvic floor