Inguinal hernia

This refers to a condition in which an organ in the abdominal cavity protrudes into the groin (the outer side of the penis in men, and the labia majora in women), forming a mass. Strictly speaking, it is divided into external inguinal hernia and internal inguinal hernia, but the latter is rare. The protruding organ is called the hernia contents, the peritoneum that surrounds the organ is called the hernia membrane, and the exit from the abdominal wall is called the internal hernia gate and external hernia gate. In adults, it often occurs in elderly people with weakened abdominal walls, heavy laborers, and women. On the other hand, in children, it occurs without exception when the peritoneal sheath that has been present since the fetal period becomes patent and becomes a hernia membrane. External inguinal hernia accounts for the majority of cases, and it is the most common disease treated in pediatric surgery. There is no hope of a complete cure other than surgery. In adults, it is caused by the weakness of the abdominal wall, and in children, the cause is sought in the patency of the sheath, not the abdominal wall, so even though the disease has the same name, the treatment methods are fundamentally different. In other words, in adults, abdominal wall reinforcement is the most important, but in children, the purpose can be achieved by high amputation of the processus vaginalis alone. If abdominal wall reinforcement is performed in children, it may cause blood circulation disorders in the spermatic arteries and result in testicular atrophy.

If an inguinal hernia is left untreated, the intestine that is the contents of the hernia may become strangled at the hernia gate, causing intestinal obstruction or blood circulation disorders, and there is a risk of intestinal necrosis. For this reason, surgery should be performed as soon as possible, even in newborns, and advances in pediatric surgery have made this possible. Hernia bands, which were commonly used in the past, are no longer recommended as they are ineffective and have many adverse effects.

[Takuji Toya]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

鼠径部（男子では陰茎外側、女子では大陰唇）に腹腔(ふくくう)内臓器が脱出し、腫瘤(しゅりゅう)を形成するものをいう。厳密には外鼠径ヘルニア、内鼠径ヘルニアに区別されるが、後者はまれである。脱出した臓器をヘルニア内容、その臓器を包む腹膜をヘルニア膜、腹壁からの脱出口を内ヘルニア門、外ヘルニア門という。成人では腹壁の弱くなった老人や重労働者、婦人などによく発症する。一方、小児では例外なく胎生期からある腹膜鞘(しょう)状突起が開存(かいぞん)してヘルニア膜となり、発症する。外鼠径ヘルニアがほとんどを占め、小児外科で取り扱う疾患のうち、もっとも頻度が高い。治療は手術以外に完治を望めない。成人の場合は腹壁の脆弱(ぜいじゃく)性に起因し、小児では腹壁でなく鞘状突起の開存に原因を求められるため、同じ病名であってもその治療法は根本的に異なる。すなわち、成人では腹壁の補強がもっともたいせつであるが、小児では腹膜鞘状突起の高位切断のみで目的が達せられる。小児で腹壁補強を行うと、精管動脈の血行障害をおこして睾丸萎縮(こうがんいしゅく)をきたすこともある。

　鼠径ヘルニアを放置すると、ヘルニア内容となった腸管がヘルニア門で絞扼(こうやく)され、腸閉塞(へいそく)または血行障害をおこし、腸管壊死(えし)をきたす危険がある。そのため、新生児であっても、できるだけ早く手術を行うべきであり、小児外科の進歩がそれを可能にした。以前よく用いられていたヘルニアバンドは効果もなく、弊害も多いので薦められない。

［戸谷拓二］

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