An omphalocele is characterized by extension of viscera, often including the liver, from a small abdominal cavity into the umbilical stalk with the viscera covered by a translucent bilaminar sac consisting of fused amnion and peritoneum (see Image 5). The sac may tear prenatally or during delivery. The umbilical vessels insert onto the sac and traverse serpiginously to the abdominal wall on the left superior aspect of the sac. Gastroschisis, not covered by a sac, is almost always immediately to the right and inferior to the abdominal wall opening and has extracorporeal viscera exposed to the amniotic cavity in utero or to the atmosphere postnatally (see Image 4).

Frequency: As much as 10% of the population develops some type of hernia during life. More than a half million hernia operations are performed in the United States each year. Fifty percent are for indirect inguinal hernias, with a male-to-female ratio of 7:1. Twenty-five percent are direct inguinal presentations. Fourteen percent are umbilical, with a female-to-male ratio of 1.7:1. Five percent are femoral, with a female-to-male ratio of 1.8:1. Ten percent are incisional, with a female-to-male ratio of 2:1. The prevalence of all varieties increases with age.

Umbilical hernia is much more common in those of African ethnicity. Epigastric hernias occur at a prevalence of 0.5%, with a male-to-female ratio of 3:1. Spigelian hernias are rare, sex and side of presentation are nearly equal, and they occur in people aged 50 years. Obturator hernias occur in older women, more commonly on the right side. Interparietal, supravesical, lumbar, sciatic, and perineal hernias are very rare.

Interparietal hernias are 70% right-sided, and a similar percentage involves testicular maldescent (ie, Denis Browne pouch). Reports of internal supravesical hernias are very limited, but internal supravesical hernias occur more often in men and elderly people. Primary perineal hernias occur most often in elderly, multiparous women.

Richter hernias manifest late in life, most often in women with femoral hernias. Littre hernias have a broad spectrum of hernia sites and occur in people of all ages. The clinical presentation is umbilical (30%), femoral (25%), and inguinal (50%).

A sliding component is found in 3% of inguinal hernias, with a left-to-right ratio of 4.5:1. Inguinal hernias occur with overwhelming predominance in men. Significant increases occur with age. Female infants have a high incidence of sliding tube, ovary, or broad ligament hernias.

The incidence of omphalocele has remained static at about 1 out of 7000 live births, while that of gastroschisis has markedly increased over the past 25 years to a current level of 1 out of 3500 live births.

Etiology: The embryology of the groin and of testicular descent largely explains indirect inguinal hernias. An indirect inguinal hernia is a congenital hernia regardless of the patient's age, and it occurs because of protrusion of an abdominal viscus into the open processus vaginalis. If the processus contains viscera, it is an indirect hernia; if peritoneal fluid fluxes between the space and the peritoneum, it is a communicating hydrocele, a noncommunicating scrotal hydrocele without exchange, or a hydrocele of the cord. In girls, it is a hydrocele of the canal of Nuck.

The inguinal canal forms by mesenchyme condensation condensing around the gubernaculum (Latin for rudder because it guides the testis into the scrotum). During the first trimester, it extends from the testis and to the labioscrotal fold. The processus vaginalis and its fascial coverings also form during the first trimester. A bilateral oblique defect in the abdominal wall develops during the sixth or seventh week of gestation as the muscular wall develops around the gubernaculum. The processus vaginalis protrudes from the peritoneal cavity and lies anteriorly, laterally, and medially to the gubernaculum by 8 weeks' gestation. The testis produces many male hormones beginning at 8 weeks' gestation.

At the beginning of the seventh month of gestation, the gubernaculum begins marked swelling influenced by a nonandrogenic hormone, probably m'an inhibiting substance, which results in expansion of the inguinal canal and the labioscrotal fold, forming the scrotum. The genitofemoral nerve also influences migration of the testis and gubernaculum into the scrotum under androgenic control. The female inguinal canal and processus is much less developed than is the male equivalent. The inferior aspect of the gubernaculum is converted to the round ligament. The craniad part of the female gubernaculum becomes the ovarian ligament.

Gonads develop on the medial aspect of the mesonephros at 5 weeks' gestation. The kidney then moves cephalad, leaving the gonad to reside in the pelvis, with a ligamentous attachment to the proximal gubernaculum, until the seventh month of gestation.

The gonads migrate along the processus vaginalis, with the ovary descending into the pelvis and the testis being enwrapped within the distal processus, the tunica vaginalis. The processus in 40-50% of boys fails to close adequately at birth. Therefore, other factors are involved in having a clinical indirect hernia. A familial tendency exists, with a relative risk of inguinal hernia of 5.8 for brothers of male cases and 4.3 for brothers of female cases and 3.7 for sisters of male cases and 17.8 for sisters of female cases.

Pathophysiology: The pinchcock action of the musculature of the internal ring during abdominal muscular straining prohibits protrusion of intestine into the patent processus. Paralysis or injury to the muscle can disable the shutter effect. Secondly, the transversus abdominis aponeurosis flattens during tensing, thus reinforcing the inguinal floor. A congenitally high position of the aponeurotic arch might preclude the buttressing effect. Neuropraxic or neurolytic sequelae of appendectomy or femoral vascular procedures might contribute to a greater incidence of hernia in these patients.

Repetitive stress is suggested by clinical presentations. Increased intra-abdominal pressure may be caused by cough; ascites; increased peritoneal fluid from biliary atresia, peritoneal dialysis, and ventriculoperitoneal shunts (see Images 12-13); intraperitoneal masses or organomegaly; obstipation; or muscular effort. Aberrant collagen states such as Aarskog, Ehlers-Danlos fetal hydantoin, Freeman-Sheldon, Hunter-Hurler, Kniest, Marfan, Morquio, and osteogenesis imperfecta; pseudo-Hurler polydystrophy and Scheie syndromes; exstrophy of bladder; neonatal intraventricular hemorrhage; myelomeningocele; and undescended testes are associated with an increased incidence of inguinal hernia. Prematurity has a strong association (9-13% incidence) with inguinal hernia in infants, with an inverse relation to weight.

The rectus sheath adjacent to groin hernias is thinner than normal. The rate of fibroblast proliferation is less than normal. The rate of collagenolysis appears increased. Sailors who developed scurvy had an increased incidence of hernia. In 1981, Cannon and Read found that increased serum elastase and decreased alpha1-antitrypsin in smokers contributes to an increase in the rate of hernia in heavy smokers. The role of biochemical or metabolic factors in the creation of inguinal hernia remains speculative.

Umbilical hernia in children is secondary to failure of closure, but only 1 out of 10 adults has a clear history of an umbilical hernia as a child. The adult umbilical hernia occurs through a canal bordered anteriorly by the linea alba, posteriorly by the umbilical fascia, and laterally by the rectus sheath. Proof that umbilical hernias persist from childhood to manifest as problems in adults is intimated by an increased incidence among black Americans. Multiparity, increased abdominal pressure, and a single midline decussation are associations.

Consider congenital hypothyroidism; fetal hydantoin syndrome; Freeman-Sheldon syndrome; Beckwith-Wiedemann syndrome; and disorders of collagen and polysaccharide metabolism, such as Hunter-Hurler, osteogenesis imperfecta, or Ehlers-Danlos syndrome, as possibilities in children with large umbilical hernias.

Deficient closure of the developing anterior wall at the umbilical stalk is the underlying embryogenic factor in both omphalocele and gastroschisis. Duhamel (1967) proposed that maldevelopment of the superior (cephalad) of the 4 folds producing the abdominal wall creates thoracic, sternal, and diaphragmatic defects with an omphalocele sac containing liver and a primitively developed heart (the upper midline syndrome or pentalogy of Cantrell). Maldevelopment of the inferior fold produces pelvic, hindgut, sacral, genital, and bladder defects with an omphalocele sac, the vesicointestinal fissure. Lateral fold maldevelopment results in omphalocele and gastroschisis. In 1980, deVries postulated that an omphalocele results from persistence of the umbilical stalk in the somatopleure. Gastroschisis follows mesenchymal damage in the developing somatopleure in the paraumbilical area, where the involuting right umbilical vein makes it vulnerable to rupture.

Chromosome abnormalities such as trisomy 13, trisomy 18, trisomy 21, and Klinefelter syndrome may be associated in about 20% of infants with omphalocele. Neurologic, urinary tract, cardiac, skeletal, and/or chromosomal anomalies are found in 67% of patients with omphaloceles. Most children with omphalocele and all children with gastroschisis have intestinal malrotation, meaning their extracoelomic location precludes normal attachment of the intestines to the posterior peritoneum.

A high coincidence of Meckel diverticulum with small omphaloceles exists, and gastroschisis has an increased incidence of intestinal atresia due to interference with the vascular supply to the intestine. Experimentally, administration of the insecticide methyl-parathion has produced gastroschisis. Transplacental transmission of such teratogens helps explain gastroschisis in siblings with different fathers.

Aberrant formation of the decussations of the linea alba, with most occurring with a midline pattern of single anterior and posterior lines, predisposes to formation of epigastric hernia (epiplocele). Abnormal orientation of the semilunar and semicircular lines in combination with obesity, increased intra-abdominal pressure, aging, and weight loss leads to production of spigelian hernias.

Internal supravesical hernias probably arise from congenital deficiency in the fasciae. The perihernial fasciae or musculature may be malformed in lumbar, femoral, and other abdominal hernias. Interparietal hernias are often a product of ectopic testicular descent. Multiparity and age produce laxity of the pelvic floor, causing obturator hernias and perineal hernia in women.

Clinical: History and physical examination axiomatically are the best means of diagnosis of hernias. Associated conditions such as ascites, constipation, obstructive uropathy, chronic obstructive pulmonary disease, or cough are carefully sought in the review of systems.

The diagnosis of hernia is usually made because a patient, parent, or physician observes a bulge that may be intermittent (see Image 6). The herniating viscus may or may not enter the space, and the bulge may disappear depending on intra-abdominal pressure. Premature infants with inguinal hernias may have accelerated growth postoperatively and have resolution of apnea after repair. Older children and adults may have a dull ache or burning pain, often worsened by exercise or straining such as coughing. Neuralgia of the ilioinguinal nerve may manifest with a sudden stabbing pain in the distribution. Infants sometimes are irritable, especially with a large hernia.

In adults, a seated examiner can best observe the patient. Examine the inguinal canal areas for the bulge. A provocative cough may help. The cough is repeated during invagination of the scrotum while feeling for the impulse. The diameter of the internal ring is assessed. Palpation of the cord structures with the finger gently rolling perpendicular to the long axis of the cord just medial to the internal ring reveals thickening of the cord. The steps are repeated with the patient prone.

Invaginating the scrotum is counterproductive in the examination of a child because a hyperactive cremasteric muscle contraction reduces hernial contents into the peritoneum. Palpation of the cord in a subtle hernia in a child reveals a thickened cord, particularly during straining, which is easily prompted by tickling the child. The sensation may be similar to rubbing layers of silk together (silk sign).

If the hernia is not demonstrable in the supine position, examine the child while applying intermittent manual pressure to the abdomen. When looking down at an angle from the infant's chest level toward the groin, a combination of gravity and increased intra-abdominal pressure inflates the open sac, confirming the hernia or hydrocele. Even with a significant hernia, the rings may be of normal size.

A hydrocele usually transilluminates. Gas-filled intestine also transilluminates, precluding diagnostic aspiration. If the scrotal size vacillates or fluid can be squeezed from the sac into the peritoneum, a communicating hydrocele is causing the swelling. Communicating hydroceles without hernia should have elective repair. Hydroceles are insignificant if they present at birth or are bilateral, soft, blue, or peritesticular or do not persist beyond 6 months and are without fluctuation in size.

An acute hydrocele may manifest as rapid, painful scrotal swelling at several years of age, simulating an incarcerated hernia. Palpation of the cord structures at the internal ring while assessing mobility helps distinguish between hydrocele and incarcerated hernia. A hydrocele moves more than an incarcerated hernia, has a defined proximal margin, and is not thick. A hydrocele of the cord manifests in the inguinal canal as a nontender, rubbery, round, nonpainful mass.

An abdominoscrotal hydrocele extends from the abdominal cavity through the inguinal canal into the scrotum. With an infant, a digital rectal examination with careful internal examination of the ring can differentiate an incarcerated hernia from a hydrocele. The child should have an operation for clarification if the situation is equivocal. Because most physiologic hydroceles resolve, operation is generally confined to those older than 1 year, those who develop communication, or those with pain.

In a sliding hernia, a portion of viscus or its mesentery constitutes part of the hernia sac. The bladder medially, the cecum on the right side, or the sigmoid colon or its mesentery on the left side may be parts of the sac.

If the visceral contents of a hernial sac do not easily reduce into the peritoneal cavity, the hernia is incarcerated, and, if it cannot be reduced, it is irreducible. In chronic hernias, adhesions may impair reduction. Up to 15% of children, especially young infants, present with incarceration. Four out of 5 do not need immediate operation because an attempt at reduction is often successful, and emergency operation has 20 times the risk of complications of elective repair. A solid, almondlike mass within the labium majus is an ovary, which is the most frequently incarcerated viscus in a girl, particularly an infant.

Hernias are the leading cause of intestinal obstruction in the world. Hidden hernias, such as obturator, femoral, or lumbar, should be considered as causes of bowel obstruction. Intense pain suggests strangulation (necrosis). Torsion of the bowel on entry into the sac may lead to precipitous symptoms; a more gradual onset arises from lymphatic, then venous, then arterial compromise from occlusion at the neck of the sac.

Spigelian hernias manifest with local pain and signs of obstruction from incarceration. Pain increases with abdominal tensing.

Interparietal hernias between layers of the abdominal wall manifest similarly. A mass may be just superior and lateral to the external ring, and the scrotum may not contain a testis. Internal supravesical hernias may have obstructive symptoms of the intestinal tract or those resembling urinary tract infection. Vague flank discomfort combined with a mass effect in the flank suggests the diagnosis of lumbar hernia. The mass gradually enlarges.

A testicular tumor is usually presumed when splenogonadal fusion presents as a scrotal mass. Splenic tissue recognized on frozen section negates the need for orchiectomy. A 2- to 4-mm mass of yellow-tan tissue found in 1 out of 40 hernia repairs is an ectopic adrenal rest. The proximity of the developing testis and adrenal gland invites adherence of the two, with the adrenal fragment accompanying the testis into the ectopic position.

The differential diagnosis of a groin mass inferior to the inguinal ligament and medial to the femoral vessels includes an incarcerated femoral hernia, involvement of the lymph nodes with a variety of inflammatory or neoplastic processes, and soft tissue tumors of the region. Peritoneal signs and intestinal obstruction are suggestive of an incarcerated femoral hernia.

With common lymph node swelling, the mass usually feels lobulated and is superficial and inferior to the femoral ring. A primary lesion should be sought by careful examination of the lymph node drainage area. Culture of the aspirate guides antibiotic therapy.

Children commonly have catscratch disease lymphadenitis. Feline contact by a scratch or bite causes Bartonella henselae infection. A papule develops in 3-5 days, followed by regional lymphadenopathy in 1-2 weeks. Attendant symptoms of fever, malaise, myalgia, anorexia, encephalitis, oculoglandular disease, or severe systemic disease complicate 12% of cases. By age 2 months, symptoms usually resolve spontaneously. Infections such as toxoplasmosis, tularemia, infectious mononucleosis, Actinomyces israelii, and human immunodeficiency virus can also cause inguinofemoral adenopathy. Some athletes may have painful reactive inguinal or femoral lymph nodes from repeated trauma.

Prevascular femoral hernia is rare and presents as a bulge. It may be mistaken for a femoral aneurysm. External femoral hernias pass beneath the inguinal ligament to lie lateral to the femoral vessels and deep to the iliopubic tract. The hernia of Laugier traverses a defect in the lacunar ligament. A hernia of Cloquet results from an abnormal insertion of the pectineus muscle, which allows perforation of the aponeurosis as the hernia sac courses over the femoral canal. The retrovascular hernia sac descends in the posterior sheath of the femoral vein.

Obturator hernia has intermittent, acute, severe hypesthesia, hyperesthesia, or pain in the medial thigh or the greater trochanter. The symptoms are usually relieved by flexion of the thigh and worsened by medial rotation, adduction, or extension. Rarely, a palpable mass in the medial upper thigh is present.

A tender, increasing mass in the gluteal area, sometimes with bowel sounds, is the usual symptom of sciatic hernias. Sciatic neuropathy and symptoms of intestinal or ureteral obstruction also occur. Perineal hernias generally manifest as a perineal mass with discomfort on sitting and obstructive symptoms with incarceration. Umbilical hernia presents as a mid abdominal bulge. Altered sensorium and obesity enhance the danger of incarceration. Hypertrophic, hyperpigmented, papyraceous skin is testimony to high pressure on the skin. The size of the fascial defect and whether it is circular provides management clues.

Diastasis recti or a widened linea alba has no significance. Small openings in the linea alba through which preperitoneal fat protrudes can be present. This occurs in children as well as adults, suggesting that the defects are congenital. The name paraumbilical hernia applies when this defect is adjacent to the umbilicus. The term epiplocele, or ventral hernia, is used for more craniad positioning. They manifest with a lump anywhere along the linea alba and have a tendency to produce sudden, severe pain with exercise.

Some neonates have delayed separation of the umbilical cord remnant associated with secondary bacterial colonization and low-grade infection. A salmon pink, cobblestone-appearing, friable mass persists at the umbilicus (ie, umbilical granuloma). A polyp with a glistening, cherry red, smooth surface is an umbilical polyp (ie, omphalomesenteric duct or urachal remnant) with intestinal or bladder mucosa present.

The 3 characteristic clinical patterns for congenital abdominal wall defects are simple omphalocele, gastroschisis, or one of the rare syndrome omphaloceles.

Maternal serum alpha-fetoprotein screening can help identify ventral wall defects in the fetus during the second trimester. Prenatal ultrasonography can define the location of the abdominal wall defect, the status of the viscera, its involvement with associated structures, and the presence of additional malformations. Recognition of a small omphalocele or hernia of the umbilical cord stalk may not occur prior to or during delivery. Compromise of small bowel or an omphalomesenteric duct then happens as the cord is clamped. The cord should be clamped away from the abdomen to prevent iatrogenic damage to the intestine in an infant with an unusual cord base or widened umbilical cord base.

Indications

In general, the presence of a hernia in the absence of mitigating factors dictates repair to obviate the complications of prolonged exposure such as incarceration, obstruction, and strangulation. Although taxis reduction of incarcerated hernia is generally safe, failure to reduce is not infrequent and mandates prompt exploration. Signs of inflammation or obstruction should obviate attempts at reduction (see Images 10-11). Difficult reduction should promptly be followed by repair. Unintentional reduction of intestine with vascular compromise leads to perforation and peritonitis with high morbidity and mortality rates. En masse reduction following vigorous attempts at reduction in a hernia with a small fibrous neck results in ongoing compromise of the entrapped bowel. Strangulation can occur in a Richter hernia without evidence of incarceration or obstruction.

Umbilical hernia repair in adults is indicated for incarceration, small neck in relation to the size of the hernia, ascites, chromatic skin change, or rupture. A rational approach to management of an umbilical hernia in a child relates to the natural history of umbilical hernias and their importance in adulthood. Most umbilical hernias close spontaneously in the preschool period, and incarceration is rare; therefore, repair of an umbilical hernia is not indicated until age 5 years unless the child has a large proboscoid hernia with thin hyperpigmented skin, the child is undergoing an operation for other reasons, or the hernia is a familial or social problem. The size of the fascial defect rather than the size of the external protrusion predicts potential for spontaneous closure. Walker (1967) showed that fascial rings measuring less than 1 cm in diameter close, while rings larger than 2 cm in diameter seldom close.

The Johns Hopkins Hospital reported only 7 children in a 15-year period with an incarcerated umbilical hernia. Omentum is the most frequently incarcerated organ. During the same 15-year period at the Johns Hopkins Hospital, 101 cases of umbilical hernia incarceration occurred in adults.

Painful preperitoneal fat in an epiplocele or paraumbilical hernia is also sometimes incarcerated. Because the defects do not close spontaneously and propensity for painful strangulation exists, repair is indicated, usually as an outpatient procedure.

Because of the potential for incarceration, spigelian hernias should be repaired, as should interparietal hernias, supravesical hernias, lumbar, obturator, sciatic, and perineal hernias.

RELEVANT ANATOMY AND CONTRAINDICATIONS

Relevant Anatomy:

Anterior abdominal wall

The anterior abdominal wall is composed of multilaminar mirror-image muscles and the associated aponeuroses, fasciae, fat, and skin. Laterally, 3 muscle layers exist with fascicles running obliquely in relation to each other. Each inserts into a flat, white tendon, ie, an aponeurosis.

The rectus abdominis muscles are the pair originating on the pubis inferiorly and inserting on the ribs superiorly. The muscle has 4 transversely oriented tendinous bands variably spaced. The linea semilunaris is at the lateral margin of the rectus abdominis muscles, where the aponeurosis serves as an insertion for the lateral musculature. The lower edge of the posterior sheath, midway between the umbilicus and the pubis, with its concavity oriented toward the pubis defines the semicircular line. Above this line, anterior and posterior laminae form from division of the internal oblique aponeurosis.

The posterior lamina joins the transversus abdominis aponeurosis and forms the posterior rectus sheath. The anterior rectus sheath results from fusion of the anterior lamina and the external oblique aponeurosis. The external oblique aponeurosis forms the external lamina of the anterior sheath below the semicircular line.

Fusion of the internal oblique and transversus abdominis aponeuroses forms the internal lamina of the anterior sheath. The posterior surface of the rectus muscles is covered with transversalis fascia below the semicircular line. The midline linea alba represents a decussation of these fibers from the different aponeurotic layers.

The external oblique muscle originates on the lower 8 ribs, with obliquely and inferiorly directed fascicles inserting into its aponeurosis. Deep to the external oblique muscle is the internal oblique muscle with obliquely and superiorly oriented fascicles arising from the iliac fascia deep to the lateral half of the inguinal ligament, the anterior two thirds of the iliac crest, and from the lumbodorsal fascia. It inserts into its aponeurosis, the rectus sheath, and into the lower ribs and cartilages superiorly.

The transversus abdominis muscle is the most internal of the lateral abdominal wall musculature. The fascicles are generally transversely oriented. It arises from the lateral iliopubic tract, from the iliac crest, the lumbodorsal fascia, and the caudad 6 ribs. It inserts principally into its aponeurosis and fuses with the internal oblique aponeurosis to become the posterior rectus sheath.

The caudad margin curves to form the transversus abdominis aponeurotic arch as the upper edge of the internal ring and above the medial floor of the inguinal canal. This arch may combine with the internal oblique aponeurosis to form the conjoined tendon in 3% of cases.

The innominate fascia overlies the external oblique muscle. The transversalis fascia forms an investing fascial envelope of the abdominal cavity. A variable layer of preperitoneal fat separates the peritoneum from the transversalis fascia.

Posterolateral (lumbar)

The iliac crest and the iliolumbar ligament lumborum from between the iliac crest and the fifth lumbar transverse process are the origins of the quadratus, and it inserts along the 12th rib. The psoas muscle arises from vertebrae T12 through L5 and passes downward under the inguinal ligament to insert on the lesser trochanter.

The serratus posterior inferior muscle originates from the lumbodorsal fascia and inserts along the 4 lowest ribs. The sacrospinalis muscle runs along the spinous processes for the entire length of the spine.

The latissimus dorsi muscle originates on the posterior third of the iliac crest, the spinous processes of the sacral and lumbar vertebrae, and the lumbodorsal fascia. From this wide origin, the muscle inserts as a tendon into the intertubercular groove of the humerus.

The superior lumbar triangle of Grynfeltt-Lesshaft is bounded superiorly by the 12th rib, the posterior lumbocostal ligament, and the serratus posterior inferior muscle; inferiorly by the superior border of the internal oblique muscle; and posteriorly by the lateral border of the sacrospinalis muscle. The deep margin of the superior lumbar triangle is the transversus abdominis muscle, and the superficial margin is the latissimus dorsi muscle. Spontaneous lumbar hernia more commonly occurs because the potential space is larger and more constant than the inferior lumbar triangle.

The inferior lumbar triangle of Petit has posterior bounds of the latissimus dorsi muscle, anterior bounds of the external oblique muscle, and inferior bounds of the iliac crest.

Inguinal region

Vessels regularly found during inguinal hernia repairs are the superficial circumflex iliac, superficial epigastric, and external pudendal arteries that arise from the proximal femoral artery and course superiorly. The inferior epigastric artery and vein course runs medially and craniad in the preperitoneal fat near the caudad margin of the internal inguinal ring.

The external iliac vessels pass posterior to the inguinal ligament and iliopubic tract and anterior to the pectineal ligament to enter the femoral sheath. The external spermatic artery arises from the inferior epigastric artery just caudad to the internal inguinal ring to supply the cremaster muscle.

The inguinal ligament bridges the space between the pubic tubercle and the anterior superior iliac spine to rotate posteriorly and then superiorly to form a shelving edge. It is the caudad edge of the external oblique aponeurosis. The ligament revolves more medially to create the lacunar ligament, which inserts on the pubis; its reflection courses medially and superiorly toward the midline. The external oblique aponeurosis has a triangular opening with a superior apex through which the cord enters the inguinal canal (external ring).

The transversus abdominis muscle predominates as a layer of the abdominal wall for the prevention of inguinal hernias. The transversus abdominis aponeurotic arch inserts inferiorly on the Cooper ligament and contributes to the anterior rectus sheath medially.

The pectineal ligament courses from the superior part of the superior pubic ramus periosteum. The components incorporate fibers from the lacunar ligament, the transversus abdominis aponeurosis, and the pectineus muscle.

An aponeurotic band from the caudad portion of the transversus abdominis muscle creates the iliopubic tract. It is the anterior margin of the femoral sheath and the caudad border of the internal ring. The course is from the superior pubic ramus medially to the iliopectineal arch and iliopsoas fascia, then anteriorly to the femoral vessels, and laterally to the anterior superior iliac spine.

The iliacus fascia thickens as it exits the pelvis to form the iliopectineal arch. The fascia curves forward, lateral to the external iliac vessels, combining with fibers from the inguinal ligament, the internal oblique and transversus abdominis muscles, and from part of the ligament lateral attachment of the iliopubic tract.

The external iliac vessels pass beneath the inguinal ligament and iliopubic tract and anterior to the pectineal ligament to enter the femoral sheath.

The femoral sheath, with contributions from transversalis, pectineus, psoas, and iliacus fasciae, has 3 compartments. A femoral hernia can occur in the most medial compartment. The femoral vein bounds the femoral canal laterally. The medial margin is transversus abdominis aponeurosis insertion and transversalis fascia.

The femoral canal holds lymphatic channels and lymph nodes. The Hesselbach triangle laterosuperior border is the inferior epigastric vessels. The inguinal ligament constitutes the lateroinferior side. The lateral edge of the rectus sheath is the medial side.

The borders of the internal inguinal ring are the transversalis fascia circumferentially and deep, the arch of the internal oblique and transversus abdominis muscles superomedially, and the iliopubic tract lateroinferiorly. The course of the spermatic cord or round ligament through the abdominal wall defines the inguinal canal.

Transversus abdominis aponeurosis and transversalis fascia combine to create the floor of the inguinal canal in 75% of people; the rest have only transversalis fascia. The external oblique aponeurosis is anterior, and the inguinal ligament is inferior.

The vas deferens and the testicular artery and vein constitute the spermatic cord. The innominate fascia extends onto the cord as the external spermatic fascia. The cremasteric fascia and the cremaster muscle extend from internal oblique muscle and its aponeurosis to provide the most external investment of the cord.

The next layer, the internal spermatic fascia, is an extension of the transversalis fascia and contains the cord structures and tunica vaginalis or an indirect hernial sac when present.

The inferior epigastric artery, which arises from the external iliac artery, courses vertically with its companion vein in the preperitoneal fat and is the defining differential between indirect inguinal hernias and direct inguinal hernias. Those presenting superolateral to the inferior epigastric vessels are indirect inguinal hernias; those arising inferomedial to these vessels are direct inguinal hernias.

The iliohypogastric and ilioinguinal nerves originate principally from the first lumbar nerve root and have contributions from the 12th thoracic root. The nerves traverse the transversus abdominis muscle in the middle of the iliac crest, are deep to the internal oblique muscle until the anterior superior iliac spine, and then become superficial just beneath the external oblique aponeurosis.

The ilioinguinal nerve then runs anterior to the spermatic cord in the canal to receive sensation from the pubis and the upper scrotum (labium majus). The genital branch of the genitofemoral nerve, which arises from first and second lumbar nerve roots, becomes superficial near the internal ring to supply motor fibers of the cremaster muscle and sensation for the scrotum and medial aspect of the upper thigh.

The intraperitoneal view has the medial umbilical ligament as the lateral border of the bladder, and the lateral umbilical ligament helps to identify the inferior epigastric vessels.

The internal inguinal ring is the apex of a triangle formed medially by the ductus deferens and laterally by the testicular vessels. The base of the triangle contains the external iliac vessels, which may be injured during laparoscopic hernia repair. The pubic tubercle, the iliopubic tract, the transversus abdominis muscular arch, the lacunar ligament, the pectineal ligament, and the lateral border of the rectus abdominis muscle are usually easily visualized.

The obturator internus muscle arises from the margins of the obturator foramen and the obturator membrane. The muscle fascicles exit the pelvis at the lesser sciatic foramen and have a tendinous insertion on the medial surface of the greater trochanter of the femur. The obturator vessels and nerve pass through the obturator canal, which is superior in the obturator foramen.

The obturator canal runs obliquely in the medial thigh, among the pectineal, external obturator, and long adductor muscles. The anterior surface of the second through fourth sacral vertebrae gives rise to the piriformis muscle, which terminates in a tendon traversing the greater sciatic foramen.

Above and below this tendon, in the greater sciatic foramen, are the suprapiriform and infrapiriform foramina. The superior gluteal vessels and nerves exit through the suprapiriform foramen, and the sciatic nerve, perineal nerves, and pelvic vessels pass through the infrapiriform foramen.

Contraindications: Contagious disease, diaper rash, nearby open wounds, an upper respiratory illness, or other intercurrent illness should delay an elective procedure. Other delays probably increase the risks of operative complications. Nonoperative observation is wise when the risk of operation exceeds that of potential problems from the hernia.

WORKUP

Lab Studies:

• Evaluation of provocative factors such as prostatism, cough, rectal cancer, and ascites for potential reversal is important.

Imaging Studies:

• Plain radiographs taken tangentially may show air in the intestine outside the abdomen, as may contrast studies of the bowel. Unfortunately, poor visualization of the perineum and pelvis occurs with these studies. Higher yields result from dynamic changes in position and/or intra-abdominal pressure during these and the following studies.

• Assessment of hidden areas is possible via external views of the intestine and their domain with herniography. The careful instillation of water-soluble, nonionic contrast through the abdominal wall can define most hidden hernias, such as interparietal, pelvic, obturator, sciatic, or other poorly palpable hernias (eg, small, recurrent hernias). Unintentional luminal contrast injection has led to infection.

• Computerized tomography scanning can elucidate extracoelomic location of bowel or bladder, as can ultrasonography.

• Ultrasonography can aid in the decision to drain or aspirate a nodal abscess. Stain or culture of nodal tissue can be used to diagnose atypical tuberculous adenitis.

Diagnostic Procedures:

• Sigmoidoscopy as a screen is no longer recommended.

Sedation and Trendelenburg positioning may aid in reduction of an incarcerated hernia. Ice cooling of an incarcerated hernia is counterproductive. Simple pressure over the distal sac usually is ineffective because the incarcerated viscera mushroom over the external ring (see Images 1-2). Pressure directed medially at the external ring and maintained for several minutes while simultaneously invaginating the distal sac often reduces a difficult incarcerated viscus. An hourglass configuration of a hernia/hydrocele complex does not reduce with pressure applied to the hydrocele portion. Properly applying pressure at the point of the hernia sac/hydrocele confluence allows reduction.

Massive hernias need prosthetic material to aid closure in most patients. Progressive pneumoperitoneum, using increasing volumes of air over time, may allow accommodation to increased intra-abdominal pressure but probably does little to increase the size of the abdominal cavity.

Cauterization with silver nitrate aids resolution of an umbilical granuloma. If a stalk is present, ligation of the base takes care of the problem. Delay until age 5 years for repair of umbilical or asymptomatic epigastric hernias can allow spontaneous closure in the majority of children. Strapping with or without a coin is not indicated in treatment of umbilical hernia because of problems with skin erosion and lack of effectiveness.

Grob introduced the use of mercurochrome as an escharotic for scarifying the intact sac of a giant omphalocele. However, the development of mercury poisoning terminated its use. Chemical dressings using silver sulfadiazine with the complication of leukopenia, povidone-iodine solution with the complication of hypothyroidism, silver nitrate solution (0.5%) with the complication of argyrism, and gentian violet have served as agents to protect against infection while the sac epithelializes. Only life-threatening associated conditions, poor probability of survival in infants, or failure of better means of coverage warrant this method today. A large residual ventral hernia results, which may be problematic because of loss of domain.

Progressive compression dressing of an omphalocele sac with an inner layer of saline-moistened dressings and an outer layer of Coban can reduce viscera over 5-10 days, after which, delayed primary fascial and skin closure is accomplished. External coverage with pigskin, skinlike polymer membrane, or human amniotic membranes can be used adjunctively in the treatment of giant omphalocele or after failed primary therapy.

Surgical therapy:

Inguinal hernia

After the diagnosis is established, an explanation of the signs, symptoms, and risks of incarceration and the timing, conduct, and risk of the procedure prepares the patient or the patient's family for the ensuing repair. Most repairs proceed within several weeks, depending on many factors, including employment, family, and insurance. Pediatric surgeons repair soon after diagnosis regardless of age or weight in healthy full-term infant boys with asymptomatic reducible inguinal hernias. In full-term girls with a reducible ovary, most operate at a close elective date; if the ovary is nonreducible but asymptomatic, more emergent timing is preferred. Premature infant repairs are usually scheduled prior to neonatal intensive care unit (NICU) discharge.

Apnea is common in infants. These infants should have an apnea monitor during the postoperative period. Adults with very large, chronic hernias should be admitted postoperatively due to the combination of ileus from extensive manipulation and the loss of domain with the attendant problems of increased pressure on the diaphragm, vena cava, kidneys, and hernia closure.

A surgeon who is unfamiliar with the special metabolic problems, tissue characteristics, and metabolic and psychological needs of children or who does not have a skilled pediatric anesthesiologist available should not attempt operation for hernia in a young child (see Image 8). Older children usually have general inhalation anesthesia, whereas anesthesia providers use spinal or continuous caudal anesthesia with preterm infants. Preemptive regional anesthesia by ilioinguinal and iliohypogastric nerve block or by caudal block decreases postoperative discomfort. Local anesthesia is sufficient for most repairs in adults, although prolonged procedures (eg, those with a large intraperitoneal component including laparoscopy) and those for recurrence may require spinal, epidural, or general anesthesia. Some cardiologists advise prophylactic antibiotics to lower the risk of endocarditis in children with associated cardiac defects; patients with ventriculoperitoneal shunts may also benefit.

Gastroschisis and omphalocele

The morbidity and mortality associated with the typical infants with omphalocele or gastroschisis over the past 35 years have greatly decreased because of better preoperative and postoperative care, ie, primarily, improved ventilator care and the ability to provide total parental nutrition during the period of transition to normal bowel function. Patients with syndromic omphaloceles have only modestly improved survival rates because of the severity of their associated defects. The improvement results from prenatal recognition, prenatal transport to pediatric surgical referral centers, and better perioperative care.

Perioperative treatment

The greatest loss of contractility and mucosal function of the bowel and the fibrous coating of the bowel in gastroschisis occurs late in gestation. Elective preterm cesarean delivery may obviate late-term intestinal damage. Reports of induced abdominal delivery after lung maturation have equal results. Elective, preterm cesarean delivery is recommended for infants with large omphaloceles to avoid damage to the sac from labor and delivery.

Placing the infant up to the axillae in a sterile plastic bag maintains sterility, prevents evaporative water loss, and decreases heat loss. The infant with gastroschisis is placed on his right side until operation to prevent vascular compromise by twisting or by kinking on the fascial edge. Wide-spectrum antibiotics should be administered.

A full preoperative assessment and adequate fluid resuscitation precede early operation. The fluid requirements for an infant with gastroschisis are 4-8 times the usual requirements for the first 24 hours of life due to visceral inflammation. Maintenance of a urinary output of 1-2 cc/kg/h by closely monitored administration of crystalloids maintains proper hydration. A sump-type nasogastric tube passed through the mouth into the stomach negates the effects of the ileus. The inflamed peritoneal and intestine capillary membranes stabilize in 12-18 hours after operation, and the fluid requirements then markedly decrease. When the capillary membrane stabilizes, exogenous albumin may be administered to elevate serum levels to 2.5-3 g/dL.

Preoperative details: Adults who present with bilateral hernias without the need for formal reconstruction can have simultaneous repair; whereas, more complex procedures should be metachronous, separated by a month or more. All children with bilateral presentation should have bilateral inguinal hernia repairs. Potential damage to the cord structures contradicts routine contralateral exploration. The surgeon can advise waiting for the contralateral hernia to appear, but peritoneoscopy through the ipsilateral inguinal sac is now recommended because only 50% of the patent processes identified become clinically apparent hernias during short-term follow-up.

If incarceration is present, a child with tachycardia, fever, or signs of obstruction must have an immediate operation. Fluid and electrolyte correction and antibiotic administration precede operation. Testicular atrophy occurs with incarcerated pediatric hernias, and the parents should be warned of the possibility.

Intraoperative details:

Basic repair techniques

The fundamentals of indirect inguinal hernia repair are more or less the same regardless of patient age at presentation. Reduction or excision of the sac and closure of the defect with minimal tension are the essential steps in any hernia repair. If tissue is attenuated sufficiently to preclude following those precepts, many techniques involving release of tension by flaps, prosthetic materials, or by a simple relaxing incision in adjacent tissue fulfills the requirements. Overlay, underlay, or sandwiching of the edges with plastic meshes makes up the majority of these techniques today.

The Bassini

The essence of the repair is apposition of the transversus abdominis and transversalis fascia and the lateral rectus sheath to the inguinal ligament, usually by imbrication (see Image 14). The Shouldice uses 2 layers of running suture in similar fashion.

The Cooper

The greatest proponent of the Cooper is McVay. The repair approximates the conjoint area, the transversus abdominis, and transversalis fascia to the pectineal ligament. Overlying the vein, these structures are sewn to the iliopubic tract. It provides a good repair for femoral hernias also.

The standard repair now uses prostheses, usually polypropylene mesh. The material can overlay, underlay, or sandwich the area or be used as a plug. It provides a tension-free repair and excellent results but has a slightly increased risk of infection.

Advocates of the preperitoneal approach claim ease in identifying the sac, reducing the contents, and dissecting the cord structures. The best uses are in incidental repair of a hernia during other abdominal procedures and repair of recurrent and femoral hernias. A Pfannenstiel, or other, incision is used to reach the preperitoneal plane. The internal inguinal ring and hernia sac are identified lateral to the inferior epigastric vessels. After dissecting the sac from the testicular vessels and vas, it is divided and the peritoneum is closed. The repair follows the pectineal approach, and mesh is often applied.

The laparoscopic approach, either properitoneal or transperitoneal, is used increasingly. Postoperative pain is lessened, full recovery is better, and return to work is faster with the scope, but price is increased when compared to more conventional approaches. Short-term recurrence data are similar, but follow-up time is insufficient to completely compare the laparoscopic approach to the more conventional approaches.

A simple repair is possible in children because of smaller size, better muscle tone in the canal, and rapid recuperation. Excision of the hernial sac (processus vaginalis) with little need for prosthetic or other reinforcement or repair of an attenuated internal ring or posterior wall of the inguinal canal is usually sufficient.

A small incision centered near the internal ring in the suprapubic skin crease provides the initial approach to pediatric hernia repair. The aponeurosis of the external oblique muscle is incised in the direction of its fibers, or the internal ring and external ring are transposed by laterally retracting the external ring. Tugging on the testis can help visualize the cord structures. The sac frequently bulges up amid the cord. The sac is elevated from the vas deferens and testicular vessels.

Short hernial sacs are freed to the internal ring, but hemisecting a long sac is helpful because unroofing the distal sac is unnecessary. Proximal dissection should extend until preperitoneal fat is circumferentially visible. Twisting the sac prior to ligation provides strength and narrows the internal ring. The sac is ligated at its base. Because of occasional postoperative "spitting" of a nonabsorbable suture such as silk, synthetic sutures are used for sac ligation. If fascial repair seems necessary, the transversalis fascia is sutured to the shelving margin of the ilioinguinal ligament.

Approximately 2% of girls with inguinal hernias have an intersex differentiation syndrome. Each girl should have the fallopian tubes and ovaries examined directly or by peritoneoscopy. The hernia sac of a female patient must be scrupulously examined for signs of testicular tissue if it contains an ovary. The most common cause is testicular feminization (androgen insensitivity) syndrome, which is a result of end-androgen resistance and causes a small testis and a rudimentary vagina (persistent genitourinary sinus) without fallopian tubes or a uterus. If a girl with a hernia has testicular feminization, perform a gonadectomy on one side and isolate the other gonad in a superficial position until puberty permits secondary sexual characteristics to develop. Hermaphrodites have an asymmetric ovotestis, which should not be removed.

The incision is closed in layers, and a single adhesive strip is placed. The testis must be pulled into the scrotum to prevent iatrogenic cryptorchidism (see Image 9).

An incarcerated object within an inguinal hernia in a girl, especially in an infant, is usually ovary. An incarcerated ovary is less reducible than is intestine, but strangulation is much less frequent, making surgical reduction of the irreducible ovary less urgent than reduction of incarcerated intestine. A child with an incarcerated hernia containing intestine that is successfully reduced should be admitted for a day to allow resolution of edema prior to repair.

A child with tachycardia, fever, or signs of obstruction must have an immediate operation. Fluid and electrolyte correction and antibiotic administration precede the operation. Testicular atrophy occurs with incarcerated pediatric hernias, and the parents should be warned of the possibility.

Exposure and opening of the sac prior to dividing the external ring permits the contained intestine to be controlled with a clamp, prohibiting unintentional release of the bowel into the abdomen. Once viability of the incarcerated intestine is assured, dividing the external ring, and sometimes the internal oblique muscles, laterally reduces it.

Laparoscopy through the hernia sac can be used to assess visceral viability if hernial content reduces before visualization. The gangrenous bowel is resected, an end-to-end anastomosis is performed, and the intestine is returned to the abdomen. Repair of a contralateral side is deferred. An apparently infarcted testis is left in place after performing a capsulotomy.

Sliding hernias

In about 40% of girls with inguinal hernia, the fallopian tube, infrequently with the ovary or uterus, is a sliding component that does not easily reduce into the abdominal cavity. The sac wall may seem too thick in the medial or lateral quadrants, or the contained viscus (particularly the tube and ovary) may not reduce into the peritoneum. The walls must then be inspected for a sliding component. The hernia sac is ligated distal to the fallopian tube and divided. The proximal sac is ligated and then invaginated into the peritoneal cavity. The internal ring is closed with sutures from the transversalis fascia to the iliopubic tract.

Masses in the femoral canal

Atypical tuberculous adenitis is adequately treated with local excision. Painful, reactive inguinal or femoral lymph nodes from repeated trauma respond to excision of the involved node. The possibility of malignancy of a mass in the femoral canal that persists despite antibiotic therapy warrants biopsy. A suspected femoral hernia, usually after a missed inguinal hernia repair, also warrants exploration. The best approach for both adenopathy and the femoral hernia is a preperitoneal approach. Reduction of incarcerated intestine is easy, and access to the lymph node is clear. A pectineal ligament repair or laparoscopic mesh placement closes the opening into the femoral canal. Groin incisions usually heal better than thigh incisions, particularly with lymph channel disruption.

Repeated trauma may cause painful reactive inguinal or femoral lymph nodes. Excision of the involved node relieves the symptoms.

Umbilical hernias

General anesthesia is used in most children, but regional or local anesthesia can be used in older children or adults. A semicircular incision in a skin crease exposes the umbilical sac. A plane encircling the sac at the level of the fascial ring, without attempt to dissect the distal sac from the skin, expedites repair. The defect is closed transversely in a single layer, or, if the defect is very large, mesh is needed. If excessively wrinkled skin appears troublesome, elasticity and growth usually correct it because the skin incision is within the umbilical fold. Removal of a circle of skin and peritoneum provides good access, and a purse sting closure provides an excellent cosmetic result. A pressure dressing is applied for several days after repair.

Epigastric hernias

Immediately prior to operation, the defect should be marked. After anesthetic induction, a small transverse incision directly overlying the defect is carried to the linea alba. Incarcerated preperitoneal fat may be either removed or returned to the properitoneum. The edges of the fascial defect are approximated with interrupted sutures. Recurrence is rare, although a second epigastric hernia may develop elsewhere in another defect.

Spigelian hernias

Despite their rarity and difficulty in diagnosis, spigelian hernias have an easy approach. A transverse incision to the sac with dissection to the neck and clean approximation of the internal oblique and transversus abdominis is all that is necessary. Laparoscopic repair allows very accurate delineation of the anatomy and ensures the diagnosis in suspect instances.

Interparietal hernias

Because most interparietal hernias have an associated undescended testis, the spermatic cord should be sought. In a young child, if the testis is nongangrenous, an orchiopexy is performed. The testes should be removed in older children and adults. The usual presentation of bowel incarceration means a properitoneal indirect inguinal hernia repair is the best approach.

Supravesical hernias

These are repaired with standard techniques for inguinal/femoral hernias, usually by way of a paramedian or midline incision. The internal supravesical hernia repair should include division and closure of the neck of the sac.

Lumbar hernias

A lumbar hernia is best approached with the patient in lateral decubitus position using a lumbar roll or kidney rest. A skin-line oblique incision extends from the 12th rib to the iliac crest. A layered closure or mesh onlay for large defects is successful.

Pelvic hernias

Obturator hernias

Obturator hernias are approached abdominally and have been repaired laparoscopically. If hernia content is difficult to reduce, incision of the obturator membrane at the inferior margin lessens the risk to the obturator vessel or nerve. Mesh closure is necessary. The other side must be viewed to preclude problems with a contralateral hernia.

Sciatic hernias

A transperitoneal approach is used in the event of incarceration. Possible neurovascular injury during reduction and repair requires careful attention posteriorly and inferolaterally for the suprapiriformis hernia, superomedially for the infrapiriformis hernia, and medially for the subspinous hernia. The defect is closed with prosthetic material.

A transgluteal repair can be used with established diagnoses of the hernia and intestinal viability. The patient is prone. The incision extends from the hernia toward the greater trochanter. The fibers of the gluteus maximus are spread to expose the piriformis muscle, the gluteal neurovascular bundle, and the sciatic nerve. A prosthetic patch closes the defect between the piriformis and the iliac or ischial bone.

Perineal hernias

A transabdominal approach with prosthetic closure is the preferred approach.

Gastroschisis and omphaloceles

The major problems with gastroschisis are reduction of the inflamed viscera into the abdomen and maintenance of effective nutrition (see Image 3). The 2 major problems in the management of omphaloceles are closure of the defect without undue tension and treatment of associated anomalies, particularly cardiac anomalies and pulmonary hypoplasia. Associated anomalies must swiftly be stabilized prior to operation.

Primary closure of both fascia and skin is the best approach for both omphalocele and gastroschisis and is always possible for hernia of the umbilical cord (see Image 7). However, increased intra-abdominal pressure with compromised ventilation can produce abdominal compartment syndrome, characterized by inferior vena caval compression, intestinal and renal poor perfusion, and lower extremity edema. Enlarging the abdominal cavity by stretching the abdominal wall, decompression of the stomach, irrigation of the intestine and colon to remove meconium, and postoperative use of ventilators and muscle relaxants frequently allows primary closure. The sac is removed at the fascial edge.

Umbilical artery and/or vein catheters can be transposed to an extraumbilical location for postoperative monitoring and fluid delivery. Vigorous attempts to decompress can cause intestinal tears and should be avoided. Intra-abdominal pressure measurements help avoid an intra-abdominal compartment syndrome. Excessively high pressures mandate immediate conversion to a Silon chimney sutured to the skin or the fascial rim (see Image 4). The gradual reduction of liver and intestine is an improvement over previous methods. Most pediatric surgeons use this technique. Fascial and skin closure occurs after complete reduction (ie, 3-7 d).

An alternative to the silo, when primary closure cannot be achieved, is abdominal binding. With sequential pressure, the viscera can be reduced into the abdomen in a similar period, followed by delayed primary closure.

A prosthetic patch can bridge the gap between the rectus muscles. Orchiopexy can be performed for cryptorchid testes at the time of final closure.

Syndrome omphaloceles

Beckwith-Wiedemann syndrome

The diagnosis should be suspected in a large neonate with macroglossia. Early administration of glucose can prevent the serious sequelae of hypoglycemia.

Pentalogy of Cantrell

This malformation of the upper abdominal fold involves anterior diaphragm and pericardial defects, a short bifid sternum, and cardiac defects associated with an omphalocele sac or, at least, hypotrophic epigastric skin. Coverage of the omphalocele during evaluation of the cardiac defects allows subsequent complete repair of cardiac, diaphragmatic, and pericardial defects.

Vesicointestinal fissure (cloacal extrophy)

This malformation of the lower fold has an inferior-sited omphalocele, exstrophy of the cecum between the hemibladders, diastasis of the symphysis pubis, a short distal colon, no rectum, a shortened small bowel, and, occasionally, meningosacral anomalies. Many infants now survive following multiple corrective intestinal and urinary tract procedures.

Umbilical remnants

Mucosal biopsy provides diagnostic confirmation of the clinical suspicion. A patent omphalomesenteric duct requires prompt excision to prevent intussusception. Fifty percent of the children with external mucosal remnants have an additional component within the abdomen. Urachal remnant should be locally excised at the umbilicus and followed caudally for a short distance toward the dome of the bladder, where it should be suture ligated and divided.

Postoperative details: Postoperatively, the patient is discharged when fully awake and drinking. Provide analgesics for the subsequent few days. Bathing is not allowed for a day or two after operation, and the adhesive strips are not replaced if they come off. Older children can return to school after 3 days; physical education and recess activities are interdicted for 2-3 weeks. Return to work is dictated by the approach and the amount of physical activity involved with the job.

Follow-up care: Accurate postoperative instruction and easy access to care if problems arise are as effective as a full postoperative visit following routine inguinal hernia repairs..

COMPLICATIONS

Inguinal hernia

Complications include recurrence, infarcted testis or ovary with atrophy, wound infection, bladder injury, iatrogenic orchiectomy or vasectomy, intestinal injury, and postoperative death usually related to complications or to coexisting risk factors. A hydrocele from fluid accumulation in the distal sac usually resolves spontaneously but sometimes may need aspiration. Most recurrences happen within 5 years of operation. The recurrence rate increases in children younger than 1 year; in elderly patients; after incarcerations; in those with ongoing increased intra-abdominal pressure, those with growth failure, prematurity, seizure disorder, orchiopexy, or chronic respiratory problems; and in girls with sliding hernias.

Technical factors increasing recurrence include an unrecognized tear in the sac, failure to repair a large internal inguinal ring, damage to the floor of the inguinal canal, and infection or other postoperative complications. A direct hernia sometimes results from vigorous dissection or simultaneous initially unrecognized hernia. A femoral hernia as a sequel of inguinal hernia repair may have primarily been overlooked. Transection of the vas deferens can cause infertility, even though unilateral, through antibody production. Iatrogenic cryptorchidism (1.3%) can occur in children if the testicle is not placed in the scrotum at the end of the operation, and this requires orchiopexy for correction. Iliohypogastric and ilioinguinal neuralgia usually regress within months. Nerve blocks or neurectomy can be used in refractory cases.

Other hernias

Recurrence, bleeding, infection, and persisting pain are potential complications for the other abdominal wall hernias. Incisional hernias may have a 30% rate of recurrence.

Gastroschisis and omphaloceles

Complications arise due to prolonged time required to reduce the included infection, dislodgment of the prosthesis, prolonged mechanical ventilation, intestinal obstruction, and Budd-Chiari syndrome due to kinking of the supra hepatic inferior vena cava.

Intestinal atresias occur in about 20% of infants with gastroschisis. Massive atresias infrequently manifest with attendant sequelae of a short gut syndrome. Maximal bowel preservation by second-look operations 24-48 hours after the initial management may be warranted.

An increased incidence of necrotizing enterocolitis has been reported. Operation seldom is needed. An increased incidence of postclosure gastroesophageal reflux and hiatus hernia may require late correction.

Uncomplicated abdominal wall hernias have a favorable prognosis. Strangulation may have a 10% associated mortality rate. Uncomplicated gastroschisis and omphalocele also have a favorable prognosis. Patients with atresia or severe associated anomalies may have a 15-50% mortality rate.


The future for treatment of most abdominal wall hernias probably lies in laparoscopic approaches. As the cost of instruments decreases, their utility in specific situations increases. Furthermore, as obliteration of the learning curve occurs, if all else is equal, less pain and better cosmesis is preferable. The proper approach to gastroschisis and omphalocele is in development. Decisions regarding method and timing of delivery and method and timing of closure have not been finalized.

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REFERENCES

• Anthony T, Bergen PC, Kim LT: Factors affecting recurrence following incisional herniorrhaphy. World J Surg 2000 Jan; 24(1): 95-100;discussion 101
• Bell C, Dubose R, Seashore J: Infant apnea detection after herniorrhaphy. J Clin Anesth 1995 May; 7(3): 219-23
• Carlson GW, Elwood E, Losken A: The role of tissue expansion in abdominal wall reconstruction. Ann Plast Surg 2000 Feb; 44(2): 147-53
• Collaboration EH: Laparoscopic compared with open methods of groin hernia repair: systematic review of randomized controlled trials. Br J Surg 2000 Jul; 87(7): 860-7
• deVries PA: The pathogenesis of gastroschisis and omphalocele. J Pediatr Surg 1980 Jun; 15(3): 245-51
• Duhamel B: [Symposium on hiatal hernia in children. VII. Surgical indications. The development of surgical indications according to pediatric opinion]. Ann Chir Infant 1967 Dec; 8(4): 317-21
• Given JP, Rubin SZ: Occurrence of contralateral inguinal hernia following unilateral repair in a pediatric hospital. J Pediatr Surg 1989 Oct; 24(10): 963-5
• Hamlin JA, Kahn AM: Herniography: a review of 333 herniograms. Am Surg 1998 Oct; 64(10): 965-9
• Heniford BT, Park A, Ramshaw BJ: Laparoscopic ventral and incisional hernia repair in 407 patients. J Am Coll Surg 2000 Jun; 190(6): 645-50
• Hodgson NC, Malthaner RA, Ostbye T: The search for an ideal method of abdominal fascial closure: a meta- analysis. Ann Surg 2000 Mar; 231(3): 436-42
• Holcomb GW 3rd: Diagnostic laparoscopy for contralateral patent processus vaginalis and nonpalpable testes. Semin Pediatr Surg 1998 Nov; 7(4): 232-8
• Kapur P, Caty MG, Glick PL: Pediatric hernias and hydroceles. Pediatr Clin North Am 1998 Aug; 45(4): 773-89
• Kundra P, Deepalakshmi K, Ravishankar M: Preemptive caudal bupivacaine and morphine for postoperative analgesia in children. Anesth Analg 1998 Jul; 87(1): 52-6
• Ramshaw BJ, Esartia P, Schwab J: Comparison of laparoscopic and open ventral herniorrhaphy. Am Surg 1999 Sep; 65(9): 827-31; discussion 831-2
• Ravichandran D, Kalambe BG, Pain JA: RANDOMIZED CLINICAL TRIAL: Pilot randomized controlled study of preservation or division of ilioinguinal nerve in open mesh repair of inguinal hernia. Br J Surg 2000 Sep; 87(9): 1166-1167
• Szymanski J, Voitk A, Joffe J: Technique and early results of outpatient laparoscopic mesh onlay repair of ventral hernias. Surg Endosc 2000 Jun; 14(6): 582-4
• Toms AP, Dixon AK, Murphy JM: Illustrated review of new imaging techniques in the diagnosis of abdominal wall hernias. Br J Surg 1999 Oct; 86(10): 1243-9
• Walker SH: The natural history of umbilical hernia. A six-year follow up of 314 Negro children with this defect. Clin Pediatr (Phila) 1967 Jan; 6(1): 29-32

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