Inguinal hernia
Encyclopedia
An inguinal hernia is a protrusion of abdominal-cavity
contents through the inguinal canal
. They are very common (lifetime risk 27% for men, 3% for women), and their repair is one of the most frequently performed surgical
operations.
There are two types of inguinal hernia
, direct and indirect, which are defined by their relationship to the inferior epigastric vessels. Direct inguinal hernias occur medial to the inferior epigastric vessels when abdominal contents herniate through a weak spot in the fascia of the posterior wall of the inguinal canal, which is formed by the transversalis fascia. Indirect inguinal hernias occur when abdominal contents protrude through the deep inguinal ring
, lateral to the inferior epigastric vessels; this may be caused by failure of embryonic closure of the processus vaginalis
.
In the case of the female, the opening of the superficial inguinal ring
is smaller than that of the male. As a result, the possibility for hernias through the inguinal canal in males is much greater because they have a larger opening and therefore a much weaker wall for the intestines to protrude through.
Inguinal hernias, in turn, belong to groin
hernias, which also includes femoral hernia
s. 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
.
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.
Differential diagnosis
of the symptoms of inguinal hernia mainly includes the following potential conditions:
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. Based on hundreds of observations during dissection, the physiological school of thought has concluded that the risk of hernia is due to a physiological difference between patients who suffer hernia and those who do not, namely the presence of aponeurotic extensions from the transversus abdominis aponurotic arch. [5]
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
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. A truss also increases the probability of complications,which include strangulation of the hernia, atrophy of the spermatic cord, and atrophy of the fascial margins.This allows the defect to enlarge and makes subsequent repair more difficult. 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. The elasticised pants used by athletes also provide useful support for the smaller hernia.
Surgical correction of inguinal hernias, called a hernia repair, is commonly 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.
Constipation after hernia repair results in strain to evacuate the bowel causing pain, and fear that the sutures may rupture. Opioid analgesia makes constipation worse. Promoting an easy bowel motion is important post-operatively.
Abdominal cavity
The abdominal cavity is the body cavity of the human body that holds the bulk of the viscera. It is located below the thoracic cavity, and above the pelvic cavity. Its dome-shaped roof is the thoracic diaphragm , and its oblique floor is the pelvic inlet...
contents through the inguinal canal
Inguinal canal
The inguinal canal is a passage in the anterior abdominal wall which in men conveys the spermatic cord and in women the round ligament. The inguinal canal is larger and more prominent in men.-Site:...
. They are very common (lifetime risk 27% for men, 3% for women), and their repair is one of the most frequently performed surgical
Surgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
operations.
There are two types of inguinal hernia
Hernia
A hernia is the protrusion of an organ or the fascia of an organ through the wall of the cavity that normally contains it. A hiatal hernia occurs when the stomach protrudes into the mediastinum through the esophageal opening in the diaphragm....
, direct and indirect, which are defined by their relationship to the inferior epigastric vessels. Direct inguinal hernias occur medial to the inferior epigastric vessels when abdominal contents herniate through a weak spot in the fascia of the posterior wall of the inguinal canal, which is formed by the transversalis fascia. Indirect inguinal hernias occur when abdominal contents protrude through the deep inguinal ring
Deep inguinal ring
The deep inguinal ring is the entrance to the inguinal canal.-Location:...
, lateral to the inferior epigastric vessels; this may be caused by failure of embryonic closure of the processus vaginalis
Processus vaginalis
The processus vaginalis is an embryonic developmental outpouching of the peritoneum.It is present from around the 12th week of gestation, and commences as a peritoneal outpouching.-Gender differences:...
.
In the case of the female, the opening of the superficial inguinal ring
Superficial inguinal ring
The superficial inguinal ring is an anatomical structure in the anterior wall of the human abdomen. It is a triangular opening that forms the exit of the inguinal canal, which houses the ilioinguinal nerve, the genital branch of the genitofemoral nerve, and the spermatic cord or the round ligament...
is smaller than that of the male. As a result, the possibility for hernias through the inguinal canal in males is much greater because they have a larger opening and therefore a much weaker wall for the intestines to protrude through.
Classification
| Type | Description | Relationship to inferior epigastric vessels Inferior epigastric vessels In human anatomy, inferior epigastric vessels refers to the inferior epigastric artery and inferior epigastric vein.... |
Covered by internal spermatic fascia Internal spermatic fascia The internal spermatic fascia is a thin layer, which loosely invests the cord; it is a continuation downward of the transversalis fascia.... ? |
Usual onset >- | indirect inguinal hernia Indirect inguinal hernia An indirect inguinal hernia is an inguinal hernia that results from the failure of embryonic closure of the deep inguinal ring after the testicle has passed through it. Like other inguinal hernias, it protrudes through the superficial inguinal ring... |
protrudes through the inguinal ring and is ultimately the result of the failure of embryonic closure of the internal inguinal ring after the testicle Testicle The testicle is the male gonad in animals. Like the ovaries to which they are homologous, testes are components of both the reproductive system and the endocrine system... passes through it |
Lateral | Yes | >- | enters through a weak point in the fascia of the abdominal wall (Hesselbach triangle) | Medial | No | Adult |
Inguinal hernias, in turn, belong to groin
Groin
In human anatomy, the groin areas are the two creases at the junction of the torso with the legs, on either side of the pubic area. This is also known as the medial compartment of the thigh. A pulled groin muscle usually refers to a painful injury sustained by straining the hip adductor muscles...
hernias, which also includes femoral hernia
Femoral hernia
A hernia is caused by the protrusion of a viscus through a weakness in the containing wall. This weakness may be inherent, as in the case of inguinal, femoral and umbilical hernias. On the other hand, the weakness may be caused by surgical incision through the muscles of the abdominal/thoracic wall...
s. A femoral hernia is not via the inguinal canal, but via the femoral canal
Femoral canal
The femoral sheath has three compartments. The lateral compartment contains the femoral artery, the intermediate compartment contains the femoral vein, and the medial and smallest compartment is called the femoral canal. The femoral canal contains efferent lymphatic vessels and a lymph node...
, which normally allows passage of the common femoral artery
Femoral artery
The femoral artery is a general term comprising a few large arteries in the thigh. They begin at the inguinal ligament and end just above the knee at adductor canal or Hunter's canal traversing the extent of the femur bone....
and vein from the pelvis to the leg.
In Amyand's hernia
Amyand's hernia
Amyand's hernia is a rare form of inguinal hernia which occurs when the appendix is included in the hernial sac and becomes incarcerated. The condition is an eponymous disease named after an English surgeon, Claudius Amyand , who performed the first successful appendectomy in 1735.Amyand's hernia...
, the content of the hernial sac is the vermiform appendix
Vermiform appendix
The appendix is a blind-ended tube connected to the cecum , from which it develops embryologically. The cecum is a pouchlike structure of the colon...
.
In Littre's hernia, the content of the hernial sac contains a Meckel's Diverticulum
Meckel's diverticulum
A Meckel's diverticulum, a true congenital diverticulum, is a small bulge in the small intestine present at birth. It is a vestigial remnant of the omphalomesenteric duct , and is the most frequent malformation of the gastrointestinal tract...
.
Signs and symptoms
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 requires surgery to correct.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
Ischemia
In medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...
and gangrene
Gangrene
Gangrene is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies . This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood...
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.
Differential diagnosis
Differential diagnosis
A differential diagnosis is a systematic diagnostic method used to identify the presence of an entity where multiple alternatives are possible , and may also refer to any of the included candidate alternatives A differential diagnosis (sometimes abbreviated DDx, ddx, DD, D/Dx, or ΔΔ) is a...
of the symptoms of inguinal hernia mainly includes the following potential conditions:
- Femoral herniaFemoral herniaA hernia is caused by the protrusion of a viscus through a weakness in the containing wall. This weakness may be inherent, as in the case of inguinal, femoral and umbilical hernias. On the other hand, the weakness may be caused by surgical incision through the muscles of the abdominal/thoracic wall...
- EpididymitisEpididymitisEpididymitis is a medical condition in which there is inflammation of the epididymis . This condition comprises gradual onset of testicular pain that can vary from mild to severe, and the scrotum may become red, warm and swollen...
- Testicular torsionTesticular torsionTesticular torsion is when the spermatic cord to a testicle twists, cutting off the blood supply. The most common symptom is acute testicular pain and the most common underlying cause is a congenital malformation known as a "bell-clapper deformity". The diagnosis is often made clinically but if it...
- LipomaLipomaA lipoma is a benign tumor composed of adipose tissue. It is the most common form of soft tissue tumor. Lipomas are soft to the touch, usually movable, and are generally painless. Many lipomas are small but can enlarge to sizes greater than six centimeters. Lipomas are commonly found in adults...
s - Inguinal adenopathy (Lymph nodeLymph nodeA lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...
Swelling) - Groin abscessAbscessAn abscess is a collection of pus that has accumulated in a cavity formed by the tissue in which the pus resides due to an infectious process or other foreign materials...
- Saphenous veinSaphenous veinSaphenous vein may refer to:*Great saphenous vein*Small saphenous vein...
dilation, called Saphena varixSaphena varixA saphena varix, or a saphenous varix is a dilation of the saphenous vein at its junction with the femoral vein in the groin.-Clinical features:... - Vascular aneurysmAneurysmAn aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart...
or pseudoaneurysmPseudoaneurysmA pseudoaneurysm, also known as a false aneurysm, is a hematoma that forms as the result of a leaking hole in an artery. Note that the hematoma forms outside the arterial wall, so it is contained by the surrounding tissues. Also it must continue to communicate with the artery to be considered a... - HydroceleHydroceleA hydrocoele denotes a pathological accumulation of serous fluid in a body cavity. It can also be noted as a minor malformation of newborns due to high levels of lead in the mother's blood during pregnancy....
- VaricoceleVaricoceleVaricocele , also known as varicoscele or varicose seal, is an abnormal enlargement of the vein that is in the scrotum draining the testicles. The testicular blood vessels originate in the abdomen and course down through the inguinal canal as part of the spermatic cord on their way to the testis...
- CryptorchidismCryptorchidismCryptorchidism is the absence of one or both testes from the scrotum. It is the most common birth defect regarding male genitalia. In unique cases, cryptorchidism can develop later in life, often as late as young adulthood. About 3% of full-term and 30% of premature infant boys are born with at...
(Undescended testes)
Pathophysiology
In men, indirect hernias follow the same route as the descending testes, which migrate from the abdomenAbdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
into the scrotum during the development of the urinary and reproductive organs
Development of the urinary and reproductive organs
The development of the urinary and reproductive organs as a part of the prenatal development, concerns the urinary system and sex organs. The latter is a part of the stages of sexual differentiation....
. The larger size of their inguinal canal
Inguinal canal
The inguinal canal is a passage in the anterior abdominal wall which in men conveys the spermatic cord and in women the round ligament. The inguinal canal is larger and more prominent in men.-Site:...
, which transmitted the testicle and accommodates the structures of the spermatic cord
Spermatic cord
The spermatic cord is the name given to the cord-like structure in males formed by the ductus deferens and surrounding tissue that run from the abdomen down to each testicle.-Contents of 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. Based on hundreds of observations during dissection, the physiological school of thought has concluded that the risk of hernia is due to a physiological difference between patients who suffer hernia and those who do not, namely the presence of aponeurotic extensions from the transversus abdominis aponurotic arch. [5]
Medical
The hernia trussTruss (medicine)
In medicine, a truss is a kind of surgical appliance, particularly one used for hernia patients. A truss provides support for the herniated area, using a pad and belt arrangement to hold it in the correct position....
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
Truss (medicine)
In medicine, a truss is a kind of surgical appliance, particularly one used for hernia patients. A truss provides support for the herniated area, using a pad and belt arrangement to hold it in the correct position....
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. A truss also increases the probability of complications,which include strangulation of the hernia, atrophy of the spermatic cord, and atrophy of the fascial margins.This allows the defect to enlarge and makes subsequent repair more difficult. 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. The elasticised pants used by athletes also provide useful support for the smaller hernia.
Surgical
Outpatient surgery
Outpatient surgery, also known as ambulatory surgery, same-day surgery or day surgery, is surgery that does not require an overnight hospital stay. The term “outpatient” arises from the fact that surgery patients may go home and do not need an overnight hospital bed...
. 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
Laparoscopy
Laparoscopy is an operation performed in the abdomen or pelvis through small incisions with the aid of a camera...
, 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.
Constipation after hernia repair results in strain to evacuate the bowel causing pain, and fear that the sutures may rupture. Opioid analgesia makes constipation worse. Promoting an easy bowel motion is important post-operatively.