Perineal hernia: surgical anatomy, embryology, and technique of repair.

Perineal hernia is the protrusion into the perineum of intraperitoneal or extraperitoneal contents through a congenital or acquired defect of the pelvic diaphragm. The first case was reported by de Garangeot in 1743. Perineal hernias may occur anteriorly or posteriorly to the superficial transverse perineal muscles. Congenital perineal hernia is a rare entity. Failure of regression of the peritoneal cul de sac of the embryo is considered a predisposing factor for hernia formation. Acquired perineal hernias are primary or secondary. Primarily acquired perineal hernias are caused by factors associated with increased intra-abdominal pressure. They are more common in females as a result of the broader female pelvis and the attenuation of the pelvic floor during pregnancy and childbirth. Secondarily acquired perineal hernias are incisional hernias associated with extensive pelvic operations such as abdominoperineal resection of the anorectum and pelvic exenteration. Pain in the perineal area, intestinal obstruction, topical skin erosion, and difficulty with urination necessitate the surgical repair of a perineal hernia. This can be accomplished through transabdominal, perineal, or combined abdominoperineal approaches. The defect in the muscles of the pelvic diaphragm may be closed either with direct suturing or by using autogenous tissues or synthetic mesh.