Inguinal hernia
From Freepedia
| Inguinal hernia | ||
|---|---|---|
| ICD-10 code: | K40 | |
| ICD-9 code: | 550 | |
Inguinal hernias are protrusions of abdominal cavity contents through an area of the abdominal wall, commonly referred to as the groin, and known in anatomic language as the inguinal area. They are very common and their repair is one of the most frequently performed surgical operations. They usually arise as a consequence of the descent of the testis from the abdomen into the scrotum during early fetal life, and are therefore far more commonly seen in men than women. They present as painless bulges in the groin area that can become more prominent when coughing, straining, or standing up. The bulge commonly disappears on lying down. The presence of pain, or the inability to "reduce" the bulge back into the abdomen, usually indicates the onset of complications.
As the hernia progresses, contents of the abdominal cavity, such as the intestine, can descend into the hernia and run the risk of being strangulated within the hernia, causing an intestinal obstruction. If the blood supply of the portion of the intestine that is caught in the hernia is compromised, gut ischemia and gangrene can result, with serious consequences. The time of occurrence of complications is not predictable; some hernias can remain static for years, others can progress rapidly from the time of onset. Therefore, provided there are no serious co-existing medical problems, patients are advised to get the hernia repaired surgically at the earliest convenience after a diagnosis is made. Emergency surgery for complications such as obstruction and strangulation carry much higher risk than planned, "elective" procedures.
Despite the profusion of medical technology that is now available, the diagnosis of inguinal hernia rests on the history given by the patient and the physician's findings on examination of the groin. No tests are needed to confirm the problem.
Surgical correction of inguinal hernia is a simple operation that is now done in most places as a "short stay" or "day care" procedure. The operation was first described by Bassini, but has since undergone numerous modifications. Currently, the repair of choice is one that involves placement of a synthetic mesh to strengthen the back wall of the inguinal canal and is called the Lichtenstein repair after the surgeon who has popularised it. The synthetic mesh used to strengthen the back wall has been made using polypropylene. The operation can be done under local anesthesia and patients can be permitted to return home the same day. Early ambulation and return to work is encouraged. Recurrence rates of the hernia after a "mesh" repair are very low.
In recent years, much like in all other areas of surgery, laparoscopic repair of inguinal hernia has emerged as an option. As the evidence exists today, it has no proven superiority to the open method other than a slightly earlier return to activity. Unlike the open method, general anesthesia is a must. It is more expensive (in most parts of the world) than open repair, and most of all, has higher rates of recurrence.
There are two types of inguinal hernia, direct and indirect, and they have different causes.
Indirect inguinal hernia
An indirect inguinal hernia is ultimately the result of the failure of embryonic closure of the internal inguinal ring after passage through it of the testicle and the trailing supply of blood vessels and nerves which make up the spermatic cord. The internal ring, which is the beginning of the inguinal canal, was initially formed by the processus vaginalis, a fold of peritoneum which breaches the abdominal wall to make way for the descending testicle. An indirect hernia occurs when intra-abdominal contents, commonly including preperitoneal fatty tissues and intestines, traverse the ring to enter the inguinal canal. As time passes, the hernia contents may enlarge, extend the length of the canal, and even exit the canal through the external inguinal ring into the scrotum. During surgical repair, or herniorraphy, a surgeon recognizes the "indirect" hernia by noting that its bulge begins lateral to the inferior epigastric vessels, indicating that it arose at the top of the inguinal canal. Conversely, the "direct" inguinal hernia enters part way down the canal through a weak point in the canal's posterior wall, and its bulge is noted to be medial to these vessels.
Direct inguinal hernias
A direct inguinal hernia protrudes through a weakened area in the back of the inguinal canal, entering the inguinal triangle, an area defined by rectus abdominis muscle, the inguinal ligament and the inferior epigastric artery.
