HERNIASHERNIASDANIEL IGO

What is a hernia?A hernia is protrusion of an organ or the muscular wall of an organ through the cavity that normally contains it.

As a rule, a hernia consists of three parts - the sac, the coverings of the sac and the contents of the sac.

Hernias by themselves may be asymptomatic, but nearly all have a potential risk of becoming strangulated.

If the blood supply is cut off at the hernia opening in the abdominal wall, it becomes a medical and surgical emergency.

Pathophysiology of Hernias

By far the most common hernias develop in the abdomen, when a weakness in the abdominal wall evolves into a localized hole, or "defect", through which adipose tissue, or abdominal organs covered with peritoneum, may protrude.

Hernias may or may not present either with pain at the site, a visible or palpable lump, or in some cases by more vague symptoms resulting from pressure on an organ which has become "stuck" in the hernia, sometimes leading to organ dysfunction. Fatty tissue usually enters a hernia first, but it may be followed by or accompanied by an organ.

Most of the time, hernias develop when pressure in the compartment of the residing organ is increased, and the boundary is weak or weakened.

Weakening of containing membranes or muscles is usually congenital, and increases with age, but it may be caused by other factors, such as stretching of muscles during pregnancy, losing weight in obese people, etc., or because of scars from previous surgery.

Many conditions chronically increase intra-abdominal pressure, and hence abdominal hernias are very frequent.

Causes of HerniaAlthough abdominal hernias can be present at birth, others develop later in life. Some involve pathways formed during fetal development, existing openings in the abdominal cavity, or areas of abdominal-wall weakness.

• Any condition that increases the pressure of the abdominal cavity may contribute to the formation or worsening of a hernia. Examples include,

◦ heavy lifting,

◦ obesity

◦ coughing,

◦ straining during a bowel movement or urination,

◦ chronic lung disease, and

◦ fluid in the abdominal cavity.

• A family history of hernias can make you more likely to develop a hernia.

Complications of Hernia

An untreated hernia may complicate by:

■ Inflammation - contents of sac have become inflamed ■ Irreducibility - contents cannot be returned to their nomal site

with simple manipulation■ Obstruction - bowel in the hernia has good blood supply but

bowel is obstructed■ Strangulation - blood supply of bowel is obstructed

Hydrocele of the hernial sac -The neck of the hernial sac gets plugged with omentum or by adhesions. Fluid then accumulates in the sac by secretion from the peritoneum , thus creating a hydrocele.

■ Haemorrhage

Hernias

Inguinal Hernia

Direct

Indirect

Femoral Hernia

Umbilical Hernia

INGUINAL HERNIA

Inguinal HerniaAnatomy - The Inguinal Canal

In infants the superficial and deep inguinal rings are almost superimposed and the obliquity of the canal is slight.

In adults the inguinal canal which is about 3.75cm long, is directed downwards and medially from the deep to the superficial inguinal ring.

In the male, the inguinal canal transmits the spermatic cord, the ilioinguinal nerve and the genital branch of the genitofemoral nerve.

In the female the round ligament replaces the spermatic cord.

Inguinal HerniaAn 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.

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.

Direct inguinal hernias occur medial to the inferior epigastric vessels when abdominal contents herniate through the external inguinal ring.

Inguinal HerniaOrigin

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.

Inguinal HerniaClinical Features

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.

Indirect Inguinal Hernia

An indirect inguinal hernia is an inguinal hernia that results from the failure of embryonic closure of the internal inguinal ring after the testicle has passed through it. Like other inguinal hernias, it protrudes through the inguinal ring. It is the most common cause of groin hernia.

In the male fetus, the peritoneum gives a coat to the testicle as it passes through this ring, forming a temporary connection called the processus vaginalis. In normal development, the processus is obliterated once the testicle is completely descended. The permanent coat of peritoneum that remains around the testicle is called the tunica vaginalis. The testicle remains connected to its blood vessels and the vas deferens, which make up the spermatic cord and descend through the inguinal canal to the scrotum.

The internal inguinal ring, which is the beginning of the inguinal canal, remains as an opening in the internal oblique muscle, which forms the muscular outer wall for the spermatic cord. When the opening is larger than necessary for passage of the spermatic cord, the stage is set for an indirect inguinal hernia. The protrusion of peritoneum through the internal inguinal ring can be considered an incomplete obliteration of the processus.

In indirect inguinal hernia, it passes through the deep inguinal ring and is located lateral to the inferior epigastric artery. Hence, the conjoint tendon is not weakened.

Indirect Inguinal Hernia

There are three types of indirect inguinal hernia

Bubonocele - The hernia is limited to the inguinal canal

Funicular - The processus vaginalis is closed just above the epididymis. The contents of the sac can be felt seperately from the the testis which lies below the hernia

Complete - A complete inguinal hernia is rarely present at birth but is commonly encountered in infancy. It also occurs in adoloscence or adult life. The testes appear to lie within the lower part of the hernia.

Indirect Inguinal Hernia

Differentials

Male

Vaginal hydrocele

encysted hydrocele

spermatocele

femoral hernia

lipoma of the cord

Female

Hydrocele of the canal of Nuck

femoral hernia

Indirect Inguinal Hernia

TreatmentOpen surgery is the most common type of treatment, accounting for 95 percent of inguinal repairs. This procedure is done under local anesthesia and requires a 4- to 6-inch incision in the groin. The doctor then pushes the herniated tissue back into place and sutures the opening shut.

Laparoscopy is done under general anesthesia and involves three small incisions (1/2 inch or less) in the abdomen which is then inflated with carbon dioxide. A laparoscope and other instruments are inserted through the incisions. Using a monitor the surgeon pushes the herniated tissue back into place and staples a patch over the opening.

Direct Inguinal Hernia

A direct inguinal hernia protrudes through a weakened area in the transversalis fascia near the medial inguinal fossa within an anatomic region known as the medial or Hesselbach’s triangle, an area defined by the edge of the rectus abdominis muscle, the inguinal ligament and the inferior epigastric artery.

These hernias are capable of exiting via the external ring, but unlike indirect inguinal hernias, they cannot move into the scrotum.

Since their abdominal walls weaken as they age, direct hernia tends to occur in the middle-aged and elderly. This is in contrast to indirect hernias which, although their etiology includes a congenital component, can occur at any age.

Direct Inguinal Hernia

Treatment

The principles of repair of a direct hernia are the same as an indirect hernia.

FEMORAL HERNIA

Femoral HerniaAnatomy - The Femoral Canal

The femoral canal is located below the inguinal ligament on the lateral aspect of the pubic tubercle.

It is bounded by the inguinal ligament anteriorly, pectineal ligament posteriorly, lacunar ligament medially, and the femoral vein laterally.

It normally contains a few lymphatics, loose areolar tissue and occasionally a lymph node called Cloquet's node.

The function of this canal appears to be to allow the femoral vein to expand when necessary to accommodate increased venous return from the leg during periods of activity.

Femoral HerniaFemoral hernias occur just below the inguinal ligament, when abdominal contents pass through the femoral canal.

Femoral hernias are a relatively uncommon type, accounting for only 3% of all hernias.

While femoral hernias can occur in both males and females, almost all of them develop in women because of the wider bone structure of the female pelvis.

Femoral hernias are more common in adults than in children.

Those that do occur in children are more likely to be associated with a connective tissue disorder or with conditions that increase intra-abdominal pressure.

Seventy percent of pediatric cases of femoral hernias occur in infants under the age of one.

Femoral Hernia

Epidemiology

The female to male ratio is about 2:1, but it is interesting that, whereas the female patients are frequently elderly, the male patients are usually between the ages of 30 and 45. The condition is more prevalent in women who have borne children than in nulliparae.

Femoral HerniasClinical Features

They typically present when standing erect as a groin lump or bulge, which may differ in size during the day, based on internal pressure variations of the intestine.

The bulge or lump typically is smaller or may not be visible in a prone position.

They may or may not be associated with pain. Often, they present with a varying degree of complication ranging from irreducibility through intestinal obstruction to frank gangrene of contained bowel.

The incidence of strangulation in femoral hernias is high. A femoral hernia has often been found to be the cause of unexplained small bowel obstruction.

The obvious finding may be a lump in the groin. Cough impulse is often absent and should not be relied on solely when making a diagnosis of femoral hernia. The lump is more globular than the pear shaped lump of the inguinal hernia.

The bulk of a femoral hernia lies below an imaginary line drawn between the anterior superior iliac spine and the pubic tubercle (which essentially represents the inguinal ligament) whereas an inguinal hernia starts above this line. Nonetheless, it is often impossible to distinguish the two preoperatively.

Femoral HerniaDifferential Diagnosis

An inguinal hernia

Saphena varix - a saccular enlargement of the termination of the great saphenous vein, usually accompanied by other signs of varicose veins.

An enlarged femoral lymph node

Lipoma

Femoral aneurysm

A distended psoas bursa

Rupture of the adductor lungus

Femoral HerniaDiagnosis

The diagnosis is largely a clinical one, generally done by physical examination of the groin.

However, in obese patients, imaging in the form of ultrasonography, CT or MRI may aid in the diagnosis.

An abdominal x-ray showing small bowel obstruction in a female patient with a painful groin lump needs no further investigation.

Femoral herniaTreatment - Surgery

Younger surgeons frequently use laparoscopic surgery (also called minimally invasive surgery) rather than "open" surgery. With key-hole surgery one or more small incisions are made that allow the surgeon to use a surgical camera and small tools to repair the hernia.

Conventional open surgery requires an incision large enough for the surgeon's hands to enter the patient.

Either open or minimally invasive surgery may be performed under general or regional anaesthesia, depending on the extent of the intervention needed. Three approaches have been described for open surgery.

■ Lockwood’s infra-inguinal approach

■ Lotheissen‘s trans-inguinal approach

■ McEvedy’s high approach

The infra-inguinal approach is the preferred method for elective repair. The trans-inguinal approach involves dissecting through the inguinal canal and carries the risk of weakening the inguinal canal. McEvedy’s approach is preferred in the emergency setting when strangulation is suspected. This allows better access to and visualisation of bowel for possible resection. In any approach, care should be taken to avoid injury to the urinary bladder which is often a part of the medial part of the hernial sac.

• Repair is either performed by suturing the inguinal ligament to the pectineal ligament using strong non-absorbable sutures or by placing a mesh plug in the femoral ring. With either technique care should be taken to avoid any pressure on the femoral vein.

UMBILICAL HERNIA

Umbilical HerniaAn umbilical hernia is an abnormal bulge that can be seen or felt at the umbilicus. This hernia develops when a portion of the lining of the abdomen, part of the intestine, and/or fluid from the abdomen, comes through the muscle of the abdominal wall.

Umbilical hernias are common, occurring in 10% to 20% of all children. They are, however, more common in people of African origin.

Low birth weight and premature infants are also more likely to have an umbilical hernia. Boys and girls are equally affected.Among adults, it is three times more common in women than in men; among children, the ration is roughly equal. An acquired umbilical hernia directly results from increased intra-abdominal pressure and is most commonly seen in obese individuals.

Umbilical Hernia

Umbilical Hernia

Umbilical HerniaPresentation

A hernia is present at the site of the umbilicus in the newborn; although sometimes quite large, these hernias tend to resolve without any treatment by around the age of 5 years.

Obstruction and strangulation of the hernia is rare because the underlying defect in the abdominal wall is larger than in an inguinal hernia of the newborn.

The size of the base of the herniated tissued is inversely correlated with risk of strangulation (i.e. narrow base is more likely to strangulate).

Babies are prone to this malformation because of the process during fetal development by which the abdominal organs form outside the abdominal cavity, later returning into it through an opening which will become the umbilicus.

Umbilical Hernia

Differential Diagnosis

Importantly this type of hernia must be distinguished from a paraumbilical hernia, which occurs in adults and involves a defect in the midline near to the umbilicus, and from omphalocele.

Umbilical HerniaTreatment

When the orifice is large (< 1 or 2 cm), 90% close within 3 years (some sources state 85% of all umbilical hernias, regardless of size, and if these hernias are asymptomatic, reducible, and don't enlarge, no surgery is needed (and in other cases it must be considered).

In some communities mothers routinely push the small bulge back in and tape a coin over the palpable hernia hole until closure occurs. This practice is not medically recommended as there is a small risk of trapping a loop of bowel under part of the coin resulting in a small area of ischemic bowel. The use of bandages or other articles to continuously reduce the hernia is not evidence-based.

An umbilical hernia can be fixed 2 different ways. The surgeon can opt to stitch the walls of the abdominal or he/she can place mesh over the opening and stitch it to the abdominal walls. The latter is of a stronger hold and is commonly used for larger tears in the abdominal wall. Most surgeons will repair the hernia 6 weeks after the baby is born.

OTHER HERNIAS

Paraumbilical Hernia

A paraumbilical hernia is a protrusion of the intestines or gut into the abdomen through a weak point of the muscles or ligaments near the navel. It can lead to discomfort when fatty tissue gets trapped and a lump can be felt or seen. Whilst they are not usually life-threatening, routine surgical treatment is usually advised to prevent enlargement or strangulation of the gut.

Treatment

The protrusion is put back within the abdomen in the correct position. Stitches are used to strengthen the weakness where the hernia has broken through.

The operation is usually performed under a general anaesthetic.

Spigelian HerniaA Spigelian hernia is a hernia through the spigelian fascia, which is the aponeurotic layer between the rectus abdominis muscle medially, and the semilunar line laterally.

These hernias almost always develop at or below the linea arcuata, probably because of the lack of posterior rectus sheath.

These are generally interparietal hernias, meaning that they do not lie below the subcutaneous fat but penetrate between the muscles of the abdominal wall; therefore, there is often no notable swelling.

Spigelian hernias are usually small and therefore risk of strangulation is high. Most occur on the right side. Most develop around age 50. Compared to other types of hernias they are rare.

Spigelian HerniaSymptoms and Diagnosis

Patients typically present with either an intermittent mass, localized pain, or signs of bowel obstruction.

Ultrasonography or a CT scan can establish the diagnosis, although CT scan provides the greatest sensitivity and specificity.

Treatment

These hernias should be repaired because of the high risk of strangulation; fortunately, surgery is straight-forward, with only larger defects requiring a mesh prosthesis.

Varied Spigelian hernia mesh repair techniques have been described, although evidence suggests laparoscopy results in less morbidity and shorter hospitalization compared with open procedures. Mesh-free laparoscopic suture repair is feasible and safe.

This novel uncomplicated approach to small Spigelian hernias combines the benefits of laparoscopic localization, reduction, and closure without the morbidity and cost associated with foreign material.

Obturator HerniaAn obturator hernia is a rare type of abdominal wall hernia in which abdominal content protrudes through the obturator foramen.

Because of differences in anatomy, it is much more common in women than in men, especially multiparous and older women who have recently lost a lot of weight.

The diagnosis is often made intraoperatively after presenting with bowel obstruction. A gynecologist may come across this type of hernias as a secondary finding during gynecological open surgery or laparoscopy

The Howship-Romberg sign is suggestive of an obturator hernia, exacerbated by thigh extension, medial rotation and adduction. It is characterized by lancilating pain in the medial thigh/obturator distribution, extending to the knee; caused by hernia compression of the obturator nerve.

Epigastric HerniaAn epigastric hernia is a type of hernia which may develop in the epigastrium. Epigastric hernias are most common in infants but may occur in humans of any age.

They typically result from a minor defect of the linea alba between the rectus abdominis muscles. This allows tissue from inside the abdomen to herniate anteriorly. On infants, this may manifest as an apparent 'bubble' under the skin of the belly between the umbilicus and xiphisternum.

Epigastric hernias are rarely harmful, but they can be surgically corrected for cosmetic reasons.

In general, any cosmetic operation to be performed on an infant will be delayed until the infant is older and better able to tolerate anaesthesia.

Epigastric Hernia

Richter’s Hernia

A Richter's hernia occurs when the antimesenteric wall of the intestine protrudes through a defect in the abdominal wall. If such a herniation becomes necrotic and is subsequently reduced during hernia repair, perforation and peritonitis may result. A Richter's hernia can result in strangulation and necrosis in the absence of intestinal obstruction. It is a relatively rare but dangerous type of hernia.

Treatment

Surgery

Incisional HerniaAn incisional hernia occurs in an area of weakness caused by an incompletely-healed surgical wound. Since median incisions in the abdomen are frequent for abdominal exploratory surgery, ventral incisional hernias are termed ventral hernias. These can be among the most frustrating and difficult hernias to treat.

Clinically, incisional hernias present as a bulge or protrusion at or near the area of a surgical incision.

Virtually any prior abdominal operation can develop an incisional hernia at the scar area (provided adequate healing does not occur), from large abdominal procedures (intestinal surgery, vascular surgery), to small incisions (appendectomy, or abdominal exploratory surgery).

While these hernias can occur at any incision, they tend to occur more commonly along a straight line from the xiphoid process of the breastbone straight down to the pubic bone, and are more complex in these regions.

Hernias in this area have a high rate of recurrence if repaired via a simple suture technique under tension. For this reason, it is especially advised that these be repaired via a tension free repair method using mesh (a type of synthetic material).

Incisional HerniaTreatment

Traditional open repair of incisional hernias can be quite difficult and complicated operations. The weakened tissue of the abdominal wall is re-incised and a repair is reinforced using a prosthetic mesh. Complications frequently occur because of the large size of the incision required to perform this surgery. These are primarily wound complications such as infection of the incision. Unfortunately, a mesh infection after this type of hernia repair most frequently requires a complete removal of the mesh and ultimately results in surgical failure. In addition, large incisions required for open repair are commonly associated with significant postoperative pain.

Laparoscopic incisional hernia repair is a new method of surgery for this condition. The operation is performed using surgical telescopes and specialized instruments. The surgical mesh is placed into the abdomen underneath the abdominal muscles through small incisions to the side of the hernia. In this manner, the weakened tissue of the original hernia is never re-incised to perform the repair and one can minimize the potential for wound complications such as infections. In addition, performance of the operation through smaller incisions can make the operation less painful and recovery quicker. Laparoscopic repair has been demonstrated to be safe and a more resilient repair than open incisional hernia repair

Locations of Hernias

References

http://www.medicalgeek.com/viva/10661-hernia-hyrdocele-sac-hydrocele-hernial-sac.html

http://en.wikipedia.org/wiki/Hernia

http://www.gpnotebook.co.uk/simplepage.cfm?ID=1120927767

http://www.shantivedhospital.com/hernia.htm

http://www.gla.ac.uk/ibls/US/fab/images/anatomy/femoral2.gif

http://www.emedicinehealth.com/hernia/article_em.htm

http://www.cincinnatichildrens.org/health/info/abdomen/diagnose/umbilical-hernia.htm