Inguinal hernia

Inguinal hernia
Classification and external resources
Diagram of an indirect, scrotal inguinal hernia ( median view from the left).
ICD-10	K40.
ICD-9	550
DiseasesDB	6806
MedlinePlus	000960
eMedicine	med/2703 emerg/251 ped/2559
MeSH	C06.405.293.249.437

An inguinal hernia (pronounced /ˈɪŋɡwɨnəl ˈhɜrniə/) is a protrusion of abdominal-cavity contents through the inguinal canal. They are very common (lifetime risk 27% for men, 3% for women^[1]), and their repair is one of the most frequently performed surgical operations.

There are two types of inguinal hernia, direct and indirect. Direct inguinal hernias occur when abdominal contents herniate through a weak point in the fascia of the abdominal wall and into the inguinal canal. Indirect inguinal hernias occur when abdominal contents protrude through the deep inguinal ring; this is ultimately caused by failure of embryonic closure of the processus vaginalis.

Origin

In men, indirect hernias follow the same route as the descending testes, which migrate from the abdomen into the scrotum during the development of the urinary and reproductive organs. The larger size of their inguinal canal, which transmitted the testicle and accommodates the structures of the spermatic cord, might be one reason why men are 25 times more likely to have an inguinal hernia than women. Although several mechanisms such as strength of the posterior wall of the inguinal canal and shutter mechanisms compensating for raised intra-abdominal pressure prevent hernia formation in normal individuals, the exact importance of each factor is still under debate.^[2]

Symptoms

Frontal view of an inguinal hernia (area shaved prior to hospitalisation and surgical repair procedure).

Hernias present as bulges in the groin area that can become more prominent when coughing, straining, or standing up. They are rarely painful, and the bulge commonly disappears on lying down. The inability to "reduce", or place the bulge back into the abdomen usually means the hernia is 'incarcerated' which is a surgical emergency.

Significant pain is suggestive of strangulated bowel (an incarcerated indirect inguinal hernia).

As the hernia progresses, contents of the abdominal cavity, such as the intestines, can descend into the hernia and run the risk of being pinched within the hernia, causing an intestinal obstruction. If the blood supply of the portion of the intestine caught in the hernia is compromised, the hernia is deemed "strangulated," and gut ischemia and gangrene can result, with potentially fatal consequences. The timing of complications is not predictable; some hernias remain static for years, others progress rapidly from the time of onset. 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 incarceration and strangulation carry much higher risk than planned, "elective" procedures.

Surgical treatment

Surgical incision in groin after inguinal hernia operation.

See main article at herniorrhaphy.

Surgical correction of inguinal hernias, called a herniorrhaphy or hernioplasty, is now often performed as outpatient surgery. There are various surgical strategies which may be considered in the planning of inguinal hernia repair. These include the consideration of mesh use, type of open repair, use of laparoscopy, type of anesthesia, appropriateness of bilateral repair, etc. During surgery conducted under local anaesthesia, the patient will be asked to cough and strain during the procedure to help in demonstrating that the repair is "tension free" and sound.^[3]

Non-surgical treatment

The hernia truss (medicine) is intended to contain a reducible inguinal hernia within the abdomen. This device fell out of favour with the advent of hernia surgery. It is not considered to provide a cure, and if the pads are hard and intrude into the hernia aperture they may cause scarring and enlargement of the aperture. In addition, most trusses with older designs are not able effectively to contain the hernia at all times, because their pads do not remain permanently in contact with the hernia. The more modern variety of truss (medicine) is made with non-intrusive flat pads and comes with a guarantee to hold the hernia securely during all activities. Although there is as yet no proof that such devices can prevent an inguinal hernia from progressing, they have been described by users as providing greater confidence and comfort when carrying out physically demanding tasks^{[citation needed]}. Their popularity is likely to increase, as many individuals with small, painless hernias are now delaying hernia surgery due to recently published reports on the incidence of Post Herniorrhaphy Pain Syndrome.

Subtypes

Inguinal hernias, in turn, belongs to groin hernias, which also includes femoral hernias. A femoral hernia is not via the inguinal canal, but via the femoral canal, which normally allows passage of the common femoral artery and vein from the pelvis to the leg.

In Amyand's hernia, the content of the hernial sac is the vermiform appendix.

In Littre's hernia, the content of the hernial sac contains a Meckel's Diverticulum.

Additional images

Different types of inguinal hernias.

Inguinal fossae

Old & new hernia scars 2009

References

External links

• Inguinal Hernia Resources
• About Inguinal Hernia's
• Post Herniorrhaphy Pain Syndrome

Images

Wikimedia Commons has media related to: Inguinal hernia

• Posterior wall of the inguinal canal at rest, Figure 3
• Posterior wall of the inguinal canal during raised intra-abdominal pressure, Figure 4