Abdominal Hernias 

Updated: Jul 23, 2019
Author: Assar A Rather, MBBS, MD, FACS; Chief Editor: John Geibel, MD, MSc, DSc, AGAF 

Overview

Practice Essentials

Abdominal wall hernias are among the most common of all surgical problems. Knowledge of these hernias (usual and unusual) and of protrusions that mimic them is an essential component of the armamentarium of the general and pediatric surgeon. More than 1 million abdominal wall hernia repairs are performed each year in the United States, with inguinal hernia repairs constituting nearly 770,000 of these cases; approximately 90% of all inguinal hernia repairs are performed on males.[1, 2, 3] See the image below.

Anatomic locations for various hernias. Anatomic locations for various hernias.

Signs and symptoms

Hernias may be detected on routine physical examination, or patients with hernias may present because of a complication associated with the hernia.

Characteristics of asymptomatic hernias are as follows:

  • Swelling or fullness at the hernia site
  • Aching sensation (radiates into the area of the hernia)
  • No true pain or tenderness upon examination
  • Enlarges with increasing intra-abdominal pressure and/or standing

Characteristics of incarcerated hernias are as follows:

  • Painful enlargement of a previous hernia or defect
  • Cannot be manipulated (either spontaneously or manually) through the fascial defect
  • Nausea, vomiting, and symptoms of bowel obstruction (possible)

Characteristics of strangulated hernias are as follows:

  • Patients have symptoms of an incarcerated hernia
  • Systemic toxicity secondary to ischemic bowel is possible
  • Strangulation is probable if pain and tenderness of an incarcerated hernia persist after reduction
  • Suspect an alternative diagnosis in patients who have a substantial amount of pain without evidence of incarceration or strangulation

When attempting to identify a hernia, look for a swelling or mass in the area of the fascial defect, as follows:

  • For inguinal hernias, place a fingertip into the scrotal sac and advance up into the inguinal canal
  • If the hernia is elsewhere on the abdomen, attempt to define the borders of the fascial defect
  • If the hernia comes from superolateral to inferomedial and strikes the distal tip of the finger, it most likely is an indirect hernia
  • If the hernia strikes the pad of the finger from deep to superficial, it is more consistent with a direct hernia
  • A bulge felt below the inguinal ligament is consistent with a femoral hernia

Characteristics of various hernia types include the following:

  • Inguinal hernia - Bulge in the inguinal region or scrotum, sometimes intermittent; may be accompanied by a dull ache or burning pain, which often worsens with exercise or straining (eg, coughing)
  • Spigelian hernia - Local pain and signs of obstruction from incarceration; pain increases with contraction of the abdominal musculature
  • Interparietal hernia - Similar to spigelian hernia; occurs most frequently in previous incisions
  • Internal supravesical hernias - Symptoms of gastrointestinal (GI) obstruction or symptoms resembling a urinary tract infection
  • Lumbar hernia - Vague flank discomfort combined with an enlarging mass in the flank; progressive protrusion through lumbar triangles, more commonly through the superior (Grynfeltt-Lesshaft) triangle than through the inferior (Petit); not prone to incarceration
  • Obturator hernia - Intermittent, acute, and severe hyperesthesia or pain in the medial thigh or in the region of the greater trochanter, usually relieved by thigh flexion and worsened by medial rotation, adduction, or extension at the hip
  • Sciatic hernia - Tender mass in the gluteal area that is increasing in size; sciatic neuropathy and symptoms of intestinal or ureteral obstruction can also occur
  • Perineal hernias - Perineal mass with discomfort on sitting and occasionally obstructive symptoms with incarceration
  • Umbilical hernia - Central, midabdominal bulge
  • Epigastric hernia - Small lumps along the linea alba reflecting openings through which preperitoneal fat can protrude; may be adjacent to the umbilicus (umbilical hernia) or more cephalad (ventral hernia [epiplocele])

See Presentation for more detail.

History and physical examination remain the best means of diagnosing hernias. The review of systems should carefully seek out associated conditions, such as ascites, constipation, obstructive uropathy, chronic obstructive pulmonary disease, and cough.

Diagnosis

Laboratory studies include the following:

  • Stain or culture of nodal tissue
  • Complete blood count (CBC)
  • Electrolytes, blood urea nitrogen (BUN), and creatinine
  • Urinalysis
  • Lactate

Imaging studies are not required in the normal workup of a hernia. However, they may be useful in certain scenarios, as follows:

  • Ultrasonography can be used in differentiating masses in the groin or abdominal wall or in differentiating testicular sources of swelling
  • If an incarcerated or strangulated hernia is suspected, upright chest films or flat and upright abdominal films may be obtained
  • Computed tomography (CT) or ultrasonography may be necessary if a good examination cannot be obtained, because of the patient’s body habitus, or in order to diagnose a spigelian or obturator hernia

See Workup for more detail.

Management

Nonoperative therapeutic measures include the following:

  • Trusses
  • Binders or corsets
  • Hernia reduction
  • Topical therapy
  • Compression dressings

Surgical options depend on type and location of hernia. Basic types of inguinal hernia repair include the following:

  • Bassini repair
  • Shouldice repair
  • Cooper repair
  • Simple inguinal hernia repair in children

Surgical approaches to other hernia types may vary, as follows:

  • Umbilical hernia - After exposure of the umbilical sac, a plane is created to encircle the sac at the level of the fascial ring, and the defect is closed transversely with interrupted sutures; if the defect is very large (>2 cm), mesh may be required
  • Epigastric hernia - A small vertical incision directly over the defect is carried to the linea alba, and incarcerated preperitoneal fat is either excised or returned to the properitoneum; the defect is closed transversely with interrupted sutures
  • Spigelian hernia - A transverse incision over the hernia to the sac allows dissection to the neck, and clean approximation of the internal oblique muscle and the transversus abdominis followed by closure of the external oblique aponeurosis completes the repair
  • Interparietal hernia - Large interparietal hernias require mesh or component separation technique
  • Supravesical hernia - The standard techniques for inguinal and femoral hernias are used, usually via a paramedian or midline incision
  • Lumbar hernia - A skin-line oblique incision is made from the 12th rib to the iliac crest; a layered closure or mesh onlay for large defects is successful
  • Obturator hernia - Generally approached abdominally and often amenable to laparoscopic repair; mesh closure is necessary for a tension-free repair
  • Sciatic hernia - A transperitoneal approach is used in the event of incarceration; a transgluteal repair can be used if the diagnosis is established and the intestine is clearly viable
  • Perineal hernia - A transabdominal approach with prosthetic closure is preferred; a combined transabdominal-perineal approach can also be used
  • Gastroschisis and omphalocele - Primary closure of fascia and skin is usually best; nonoperative management of gastroschisis (plastic closure) is an alternative to conventional primary operative closure or staged silo closure
  • Femoral hernia - A standard Cooper ligament repair, a preperitoneal approach, or a laparoscopic approach may be used; the procedure includes dissection and reduction of the hernia sac and obliteration of the defect in the femoral canal by approximating the iliopubic tract to the pectineal (Cooper) ligament or by using a mesh

See Treatment and Medication for more detail.

Background

Uncommon in other animals, abdominal wall hernias are among the most common of all surgical problems. They are a leading cause of work loss and disability and are sometimes lethal. Knowledge of hernias of the abdominal wall (usual and unusual) and of the protrusions that mimic hernias is an essential component of the armamentarium of the general and pediatric surgeon.

Abdominal wall hernias are commonly described in terms of their anatomic location. Four of the most common types are shown in the image below.

Anatomic locations for various hernias. Anatomic locations for various hernias.

Operative management of hernias, despite being described since antiquity and constituting an essential part of the general surgeon’s repertoire of operations, remains controversial. By definition, a hernia is an abnormal protrusion from one anatomic space to another, with the protruded parts generally contained in a saclike structure formed by the membrane that naturally lines the cavity.

Variants on the definition of hernia exist with regard to congenital abdominal wall defects. An omphalocele is characterized by extension of viscera from the abdominal cavity into the umbilical stalk, with the contents covered by a translucent, bilaminar sac consisting of fused amnion and peritoneum. On occasion, the sac tears prenatally or during delivery, thus becoming harder to identify. The underlying abdominal wall defect exceeds 4 cm. The umbilical vessels insert onto the sac and travel along its left superior aspect to the abdominal wall.

On the other hand, gastroschisis is present when midgut viscera protrude through a central abdominal fascial defect and are not covered by a sac. In this case, the extracorporeal viscera are exposed to the amniotic fluid in utero or to the atmosphere postnatally. The responsible fascial defect is usually less than 4 cm and is almost always immediately to the right and inferior to the umbilicus.

Anatomy

Anterior abdominal wall

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

The paired rectus abdominis muscles originate on the pubis inferiorly and insert on the ribs superiorly. The muscle has four transversely oriented tendinous bands, variably spaced. At the lateral margin of the rectus abdominis muscles is the linea semilunaris, 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 eight 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 the lumbodorsal fascia. The internal oblique muscle inserts into its aponeurosis, the rectus sheath, and the lower ribs and cartilages superiorly.

The transversus abdominis is the most internal of the lateral abdominal wall muscles. The fascicles generally are transversely oriented. The transversus abdominis arises from the lateral iliopubic tract, the iliac crest, the lumbodorsal fascia, and the caudad six 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. In 3% of cases, this arch may combine with the internal oblique aponeurosis to form the conjoined tendon.

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 region

In the posterolateral (lumbar) region, the quadratus originates from the iliac crest and the iliolumbar ligament from between the iliac crest and the fifth lumbar transverse process. It then inserts along the 12th rib. The psoas arises from vertebrae T12-L5 and passes downward under the inguinal ligament to insert on the lesser trochanter.

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

The latissimus dorsi 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; inferiorly by the superior border of the internal oblique muscle; and posteriorly by the lateral border of the sacrospinalis. The deep margin of the superior lumbar triangle is the transversus abdominis, and the superficial margin is the latissimus dorsi. Spontaneous lumbar hernias occur more commonly because the potential space is larger and more constant than the inferior lumbar triangle.

The inferior lumbar triangle of Petit is bounded posteriorly by the latissimus dorsi, anteriorly by the external oblique muscle, and inferiorly by the iliac crest.

Inguinal region

Vessels regularly found during inguinal hernia repairs are the superficial circumflex iliac, superficial epigastric, and external pudendal arteries, which arise from the proximal femoral artery and course superiorly. The inferior epigastric artery and vein run medially and cephalad 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 and rotates posteriorly and then superiorly to form a shelving edge. It is the caudad edge of the external oblique aponeurosis. This ligament revolves medially to create the lacunar ligament, which inserts on the pubis and 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.

The transversus abdominis is the predominant abdominal wall layer 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.

An aponeurotic band from the caudad portion of the transversus abdominis 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, anterior to the femoral vessels, and then 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, and combines with fibers from the inguinal ligament, from the internal oblique muscle and the transversus abdominis, and from part of the ligament lateral attachment of the iliopubic tract. The external iliac vessels pass beneath the inguinal ligament and iliopubic tract but anterior to the pectineal ligament to enter the femoral sheath.

The femoral sheath, with contributions from the transversalis, pectineus, psoas, and iliacus fasciae, has three compartments. A femoral hernia most often occurs in the most medial compartment. The femoral canal is bounded laterally by the femoral vein. The medial margin is the transversus abdominis aponeurosis insertion and transversalis fascia. The femoral canal holds lymphatic channels and lymph nodes.

The superolateral border of the Hesselbach triangle is the inferior epigastric vessels. The inguinal ligament constitutes the inferolateral side. The lateral edge of the rectus sheath is the medial side.

The internal ring is bordered by the transversalis fascia circumferentially and deep, the arch of the internal oblique and transversus abdominis muscles superomedially, and the iliopubic tract inferolaterally. 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 make the floor of the inguinal canal in 75% of persons (a minority 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 and courses with its companion vein vertically in the preperitoneal fat, is the anatomic point differentiating indirect inguinal hernias from direct inguinal hernias. Hernias presenting superolateral to the inferior epigastric vessels are indirect inguinal hernias, whereas 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 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 the 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 the 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 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 usually are easily visualized.

The obturator internus 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 between the pectineus, obturator externus, and adductor longus. The anterior surface of sacral vertebrae 2-4 gives rise to the piriformis to have 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; the sciatic nerve, perineal nerves, and pelvic vessels pass through the infrapiriform foramen.

Pathophysiology

Inguinal hernia

The pinchcock action of the internal ring musculature during abdominal muscular straining prohibits protrusion of the intestine into a patent processus. Muscle paralysis or injury can disable the shutter effect. In addition, the transversus abdominis aponeurosis flattens during tensing, thus reinforcing the inguinal floor. A congenitally high position of the aponeurotic arch may preclude the buttressing effect. Neurapraxic or neurolytic sequelae of appendectomy or femoral vascular procedures may increase the incidence of hernia in these patients.

Clinical presentations suggest repetitive stress as a factor in hernia development. Increased intra-abdominal pressure is seen in a variety of disease states and seems to contribute to hernia formation in these populations. Elevated intra-abdominal pressure is associated with chronic cough, ascites, increased peritoneal fluid from biliary atresia, peritoneal dialysis or ventriculoperitoneal shunts, intraperitoneal masses or organomegaly, and obstipation. (See the images below.)

Ventriculoperitoneal shunt, decreased activity, an Ventriculoperitoneal shunt, decreased activity, and acute scrotal swelling in 6-month-old boy.
Ventriculoperitoneal shunt, decreased activity, an Ventriculoperitoneal shunt, decreased activity, and acute scrotal swelling in 6-month-old boy. Abdominal radiograph shows incarcerated shunt within communicating hydrocele. Repair of hydrocele relieved increased intracranial pressure.

Other conditions associated with an increased incidence of inguinal hernias are exstrophy of bladder, neonatal intraventricular hemorrhage, myelomeningocele, and undescended testes. A high incidence (16-25%) of inguinal hernias occurs in premature infants; this incidence is inversely related to weight.

The rectus sheath adjacent to groin hernias is thinner than normal. The rate of fibroblast proliferation is less than normal, and the rate of collagenolysis appears increased. Sailors who developed scurvy had an increased incidence of hernia. Aberrant collagen states (eg, Ehlers-Danlos, fetal hydantoin, Freeman-Sheldon, Hunter-Hurler, Kniest, Marfan, and Morquio syndromes), have increased rates of hernia formation, as do osteogenesis imperfecta, pseudo-Hurler polydystrophy, and Scheie syndrome.

Acquired elastase deficiency also can lead to increased hernia formation. In 1981, Cannon and Read found that the increased serum elastase and decreased alpha1 -antitrypsin levels associated with smoking contribute to an increased rate of hernia in heavy smokers. The contribution of biochemical or metabolic factors to the creation of inguinal hernias remains a matter for speculation.

Inguinal hernias are commonly classified as either direct or indirect. A direct inguinal hernia usually occurs as a consequence of a defect or weakness in the transversalis fascia area of the Hesselbach triangle. The triangle is defined inferiorly by the inguinal ligament, laterally by the inferior epigastric arteries, and medially by the conjoined tendon.[4]

An indirect inguinal hernia follows the tract through the inguinal canal. It results from a persistent processus vaginalis. The inguinal canal begins in the intra-abdominal cavity at the internal ring, approximately midway between the pubic symphysis and the anterior superior iliac spine, and courses down along the inguinal ligament to the external ring, located medial to the inferior epigastric arteries, subcutaneously and slightly above the pubic tubercle. The hernia contents then follow the tract of the testicle down into the scrotal sac.[5, 6, 7]

Femoral hernia

A femoral hernia follows the tract below the inguinal ligament through the femoral canal. The canal lies medial to the femoral vein and lateral to the lacunar (Gimbernat) ligament. Because femoral hernias protrude through such a small defined space, they frequently become incarcerated or strangulated.[8] Perihernial fasciae or muscles may be malformed.[9]

Umbilical hernia

An umbilical hernia occurs through the umbilical fibromuscular ring, which is usually obliterated by age 2 years. (See the image below.) They are congenital in origin and are repaired if they persist in children older than 2-4 years.[5, 4]

Hernia of umbilical cord. Hernia of umbilical cord.

Although umbilical hernias in children arise from failed closure of the umbilical ring, only one in 10 adults with umbilical hernias had this defect as a child. Adult umbilical hernias occur 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 present in adulthood is only hinted at by an increased incidence among black Americans. Multiparity, increased abdominal pressure, and a single midline decussation are associated with umbilical hernias.

Congenital hypothyroidism, fetal hydantoin syndrome, Freeman-Sheldon syndrome, Beckwith-Wiedemann syndrome, and disorders of collagen and polysaccharide metabolism (such as Hunter-Hurler syndrome, osteogenesis imperfecta, and Ehlers-Danlos syndrome), should be considered as possibilities in children with large umbilical hernias.

Richter hernia

A Richter hernia occurs when only the antimesenteric border of the bowel herniates through the fascial defect. This hernia involves only a portion of the circumference of the bowel. Thus, the bowel may not be obstructed, even if the hernia is incarcerated or strangulated, and the patient may not present with vomiting. A Richter hernia can occur with any of the abdominal hernias and is particularly dangerous in that a portion of strangulated bowel may inadvertently be reduced into the abdominal cavity, leading to perforation and peritonitis.[10]

Incisional hernia

An incisional hernia is an iatrogenic condition that occurs in 2-10% of all abdominal operations secondary to breakdown of the fascial closure of a surgical procedure. (See Guidelines.) Even after repair, recurrence rates approach 20-45%.

Spigelian hernia

A spigelian hernia occurs through a defect in the spigelian fascia, defined by the lateral edge of the rectus abdominis at the semilunar line (from costal arch to pubic tubercle). Abnormal orientation of the semilunar and semicircular lines, along with obesity, increased intra-abdominal pressure, aging, and rapid weight loss, leads to the production of spigelian hernias.

There are two subtypes of spigelian hernia, interstitial and subcutaneous. Distinguishing between these subtypes helps optimize the surgical approach (when indicated) and is best done by means of computed tomography (CT).[11, 12, 13]

Obturator hernia

An obturator hernia passes through the obturator foramen, following the path of the obturator nerves and muscles. There is a strong female preponderance (female-to-male ratio, 6:1), because of a gender-specific larger canal diameter; this hernia is also much more likely to occur in the elderly. Because of its anatomic position, an obturator hernia more commonly presents as a bowel obstruction than as a protrusion of bowel contents.[14, 10]

Other hernias

Aberrant formation of the decussations of the linea alba, leading to a midline pattern of single anterior and posterior lines, predisposes to the formation of epigastric hernias (epiploceles). Internal supravesical hernias probably arise from a congenital fascial deficiency. Perihernial fasciae or muscles may be malformed in lumbar hernias. Interparietal hernias are often a product of ectopic testicular descent. Multiparity and age produce laxity of the pelvic floor to cause perineal hernias.

Congenital abdominal wall defects

The underlying embryogenic factor in omphalocele and gastroschisis is deficient closure of the developing anterior wall at the umbilical stalk. Variations in lateral fold migration can result in both of these defects.[15] In addition, most children with omphalocele and all children with gastroschisis have intestinal malrotation; their extracoelomic location precludes normal attachment of the intestines to the posterior peritoneum.

Improper development of other portions of the abdominal wall leads to specific anomalies. In 1967, Duhamel proposed that maldevelopment of the superior (cephalad) fold of the abdominal wall leads to the thoracic, sternal and diaphragmatic, and abdominal wall defects that make up the upper midline syndrome (pentalogy of Cantrell). This syndrome includes a bifid sternal cleft, an anterior diaphragmatic defect, an anterior pericardial defect, an epigastric omphalocele, and congenital cardiac defects.

Maldevelopment of the inferior (caudal) fold produces pelvic, hindgut, sacral, genital, and bladder defects. Lower midline syndrome includes a hypogastric omphalocele, exstrophy of the bladder or cloaca, vesicointestinal fissure, colonic atresia, imperforate anus, sacral vertebral defects, and often meningoceles.

Lateral fold maldevelopment results in omphalocele (see the image below), as well as gastroschisis. It has been postulated that an omphalocele results from persistence of the umbilical stalk in the somatopleure. Approximately 20% of infants with omphaloceles have an associated chromosomal abnormality (eg, trisomy 13, trisomy 18, trisomy 21, or Klinefelter syndrome).

Note translucent sac in baby with large omphalocel Note translucent sac in baby with large omphalocele. Umbilical vessels attach to sac.

An omphalocele-exstrophy-imperforate anus-spinal defects (OEIS) complex is characterized by a combination of omphalocele, exstrophy of the bladder, an imperforate anus, and spinal defects.[16] More than 50% of infants with omphaloceles have associated neurologic, urinary tract, cardiac, and skeletal anomalies. The liver is present in the omphalocele sac in 35% of patients. In small omphaloceles, there is a high coincidence of Meckel diverticulum.

Maternal smoking is associated with an increased prevalence of omphalocele and gastroschisis. An increased incidence of abdominal wall defects is related to surface water atrazine and nitrate levels.[17]

Gastroschisis is thought to be the result of a failure of the umbilical coelom to develop to an appropriate size. The intestine then ruptures out of the body wall to the right of the umbilicus, where a slight weakness exists secondary to resorption of the right umbilical vein early in gestation (see the image below). Gastroschisis is associated with intestinal atresias in 10-15% of cases, probably as a consequence of interruption of the vascular supply to the intestine.

In this baby with gastroschisis, bowel is uncovere In this baby with gastroschisis, bowel is uncovered and presents to right inferior aspect of cord.

Experimentally, administration of the insecticide methylparathion has produced gastroschisis. Transplacental transmission of such teratogens helps explain gastroschisis in siblings with different fathers.

Etiology

The etiology of indirect hernias is largely explainable in terms of the embryology of the groin and of testicular descent. An indirect inguinal hernia is a congenital hernia, regardless of the patient’s age. It occurs because of protrusion of an abdominal viscus into an open processus vaginalis. The following terms are employed:

  • If the processus contains viscera, the patient has an indirect inguinal hernia
  • If peritoneal fluid fluxes between the space and the peritoneum, the patient has a communicating hydrocele
  • If fluid accumulates in the scrotum or spermatic cord without exchange of fluid with the peritoneum, the patient has a noncommunicating scrotal hydrocele or a hydrocele of the cord; in a girl, fluid accumulation in the processus results in a hydrocele of the canal of Nuck

The inguinal canal forms by mesenchyme condensation around the gubernaculum. During the first trimester, the gubernaculum extends from the testis to the labioscrotal fold, and the processus vaginalis and its fascial coverings form. A bilateral oblique defect in the abdominal wall develops during week 6 or 7 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 week 8 of gestation.

Beginning at week 8 of gestation, the testis produces many male hormones. At the beginning of month 7, the gubernaculum begins a marked swelling influenced by a nonandrogenic hormone, probably a müllerian inhibiting substance. This 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 are much less developed than their male equivalents. The inferior aspect of the gubernaculum is converted to the round ligament. The cephalad part of the female gubernaculum becomes the ovarian ligament.

Gonads develop on the medial aspect of the mesonephros during week 5 of gestation. The kidney then moves cephalad, leaving the gonad to reside in the pelvis until month 7 of gestation. During this time, it retains a ligamentous attachment to the proximal gubernaculum.

The gonads then migrate along the processus vaginalis, with the ovary descending into the pelvis and the testis being wrapped within the distal processus (tunica vaginalis). The processus fails to close adequately at birth in 40-50% of boys. Therefore, other factors play a role in the development of a clinical indirect hernia. A familial tendency exists, with 11.5% of patients having a family history. The relative risk of inguinal hernia is 5.8 for brothers of male cases, 4.3 for brothers of female cases, 3.7 for sisters of male cases, and 17.8 for sisters of female cases.

More generally, any condition that increases the pressure in the intra-abdominal cavity may contribute to the formation of a hernia, including the following:

  • Marked obesity
  • Heavy lifting
  • Coughing
  • Straining with defecation or urination
  • Ascites
  • Peritoneal dialysis
  • Ventriculoperitoneal shunt
  • Chronic obstructive pulmonary disease (COPD)
  • Family history of hernias [18]

Epidemiology

United States statistics

As much as 10% of the population develops some type of hernia during life.[19] More than 1 million abdominal hernia repairs are performed each year, with inguinal hernia repairs constituting nearly 770,000 of these cases.[1, 2, 3] Frequencies of various types of hernias are as follows:

  • Approximately 75% of all hernias are inguinal; of these, 50% are indirect (male-to-female ratio, 7:1), with a right-side predominance, and 25% are direct [5] ; 3% of inguinal hernias have a sliding component, most often on the left side (left-to-right ratio, 4.5:1)
  • About 14% of hernias are umbilical
  • About 10% of hernias are incisional or ventral (female-to-male ratio, 2:1) [7]
  • Only 3-5% of hernias are femoral
  • Interparietal, supravesical, lumbar, sciatic, and perineal hernias are rare; interparietal hernias are on the right side in 70% of cases, and a similar percentage of cases involve testicular maldescent (Denis-Browne pouch)

In the case of congenital abdominal wall defects, the incidence of omphalocele has increased only slightly over the past few decades, to a current level of about 1-2.5 in 5000 live births. In contrast, the incidence of gastroschisis has increased markedly over the past 25 years, to a current level of 1 in 3600 live births. In some areas, the prevalence of gastroschisis has increased by as much as 400% over the past two decades.

International statistics

Data from developing countries are limited. Consequently, accurate determinations of incidence and prevalence are unavailable. Current epidemiologic assessments suggest that gender distribution and anatomic distribution are similar to those in more developed countries.

Age-related demographics

The prevalence of all varieties of hernias increases with age.

The incidence of inguinal hernias in children is as high as 4.5%. Indirect hernias usually present during the first year of life, but they may not appear until middle or old age. Indirect hernias are more common in premature infants than in term infants; they develop in 13% of infants born before 32 weeks’ gestation.[2] Direct hernias occur in older patients as a result of relaxation of abdominal wall musculature and thinning of the fascia.

Umbilical hernias occur in approximately one of every six children.[2, 5] They usually develop in infants and reach their maximal size by the first month of life. Most hernias of this type close spontaneously by the first year of life; the incidence in children older than 1 year is only 2-10%.[20]

Spigelian hernias are rare and typically occur around the age of 50 years; no sex or side predilection is reported. Primary perineal hernias occur most often in elderly multiparous women. Obturator hernias occur most often in thin, elderly women and are more common on the right side. Richter hernias present late in life, most often in women with femoral hernias. Littre hernias have a much broader spectrum of hernia site and occur across all ages.

The incidence of incarcerated or strangulated hernias in pediatric patients is 10-20%; 50% of these occur in infants younger than 6 months.[2]

Sex-related demographics

Inguinal hernias are the most common type in both males and females; approximately 25% of males and 2% of females have an inguinal hernia over the course of their lifetime.[3, 21] The male-to-female ratio for indirect inguinal hernia is 7:1.

Sliding hernias are much more common in men than in women, and the predominance increases with age. Female infants have a high incidence of sliding tube, ovary, or broad ligament hernias.

Femoral hernias (though rare overall) occur more frequently in women because of the differences in the pelvic anatomy (female-to-male ratio, 1.8:1). Umbilical hernias are equally common in male and female children but are 3 times more frequent in female adults than in male adults (overall female-to-male ratio, 1.7:1). Incisional or ventral hernias are also more common in females (female-to-male ratio, 2:1), as are obturator hernias (female-to-male ratio, 6:1).[21]

Epigastric hernias have a prevalence of 0.5% and are more common in males (male-to-female ratio, 3:1). Reports of internal supravesical hernias are limited, but the literature suggests that they occur more often in men and in elderly people.

Race-related demographics

Umbilical hernias are much more common in persons of African ethnicity.[22] With respect to the pediatric population, umbilical hernias occur eight times more frequently in black infants than in white infants.[21]

Prognosis

The prognosis depends on the type and size of hernia, as well as on the ability to reduce risk factors associated with the development of hernias. As a rule, the prognosis is good with timely diagnosis and repair. Morbidity typically is secondary either to missing the diagnosis of the hernia or to complications associated with management of the disease.

A hernia can lead to an incarcerated and often obstructed bowel, or even to a strangulated bowel with a compromised blood supply, which, if missed, can result in bowel perforation and peritonitis. Reduction of the strangulated bowel leads to persistent ischemia or necrosis with no clinical improvement. Surgical intervention is required to prevent further complications (eg, perforation and sepsis.

In general, patients with uncomplicated inguinal and abdominal wall hernias do well. However, mortality is 10% for those who have hernias with associated strangulation. It should be kept in mind that surgery to repair the hernia or manage its complications may leave the patient at risk for infection or intra-abdominal adhesions. In addition, hernias can reappear in the same location, even after surgical repair.

In a study investigating complications during and after 780 laparoscopic inguinal herniorrhaphies in 569 patients, Coelho et al found that hernias recurred in 14 patients (2.5%) and that intraoperative complications occurred in 28 (4.9%), with extensive subcutaneous emphysema being the most common complication.[23]

Postoperative complications developed in 35 patients (6.2%). Small bowel perforation occurred in one patient, and bladder perforation occurred in another.[23] One cohort member developed an extensive, preperitoneal Mycobacterium massiliense infection. No cohort members died. The authors concluded that despite having a low mortality, laparoscopic inguinal herniorrhaphy can result in life-threatening complications.

Inguinal hernia

Potential complications of inguinal hernia repair include the following:

  • Hernia recurrence
  • Infarcted testis or ovary with subsequent atrophy (see the images below)
  • Wound infection
  • Bladder injury
  • Iatrogenic orchiectomy or vasectomy
  • Intestinal injury
Atrophy of right testis after hernia repair. Note Atrophy of right testis after hernia repair. Note adult-type incision.
Testis at operation in 2-month-old boy with histor Testis at operation in 2-month-old boy with history of irritability and vomiting for 36 hours. Capsulotomy was performed, but atrophy occurred. Patient also required bowel resection.

Postoperative death is usually related either to complications (eg, strangulated bowel) or to preexisting risk factors.[24] A postoperative hydrocele results from fluid accumulation in the distal sac. This usually resolves spontaneously but sometimes must be aspirated.

A femoral hernia as a sequela of inguinal hernia repair may have been overlooked initially. Unilateral transection of the vas deferens can cause infertility through antibody production. Iatrogenic cryptorchidism can occur in children (1.3%) if the testicle is not placed in the scrotum at the end of the operation; orchiopexy is required for correction. Iliohypogastric and ilioinguinal neuralgia may develop but usually will regress within months; in refractory cases, nerve blocks or neurectomy may be employed.

Most recurrences develop within 5 years after the operation. They are often associated with incarcerated hernias, concurrent orchiopexy, sliding hernias (in girls), or emergency operations. The recurrence rate is higher in children younger than 1 year and in the elderly. It is also higher in patients with ongoing increased intra-abdominal pressure, growth failure and malnutrition, prematurity, seizure disorder, or chronic respiratory problems.

Technical factors that increase the likelihood of recurrence include the following:

  • Unrecognized tear in the sac
  • Failure to repair a large internal inguinal ring
  • Damage to the floor of the inguinal canal
  • Infection or other postoperative complications

In some cases, a direct hernia may result from vigorous dissection; in others, it may be a simultaneous hernia that was initially unrecognized.

Other hernia types

Recurrence, bleeding, infection, and persisting pain are potential complications for the other types of abdominal wall hernia. The rate of recurrence for incisional hernias may be as high as 30%. The addition of mesh to most abdominal wall hernia repairs is decreasing the incidence of recurrence.

Gastroschisis and omphalocele

Infants with uncomplicated gastroschisis and omphalocele generally fare well, with a mortality of less than 5%.[25] Complications arising from the prolonged time required to reduce the contents into the abdomen include the following:

  • Infection
  • Dislodgment of the prosthesis
  • Prolonged mechanical ventilation
  • Intestinal obstruction
  • Budd-Chiari syndrome (due to kinking of the suprahepatic inferior vena cava)

However, mortality among infants with gastroschisis or omphalocele who have intestinal atresia or severe associated anomalies is substantially higher, in the range of 15-50%.

Intestinal atresias occur in about 20% of infants with gastroschisis. Massive atresias present infrequently with their attendant sequela of short gut syndrome. Maximal bowel preservation, achieved by means of “second-look” operations 24-48 hours after initial management, may be warranted. Infants with gastroschisis are at risk for necrotizing enterocolitis after the initiation of feeding. This is managed by bowel rest and broad-spectrum antibiotics; surgery is seldom necessary.

An increased incidence of gastroesophageal reflux after closure of gastroschisis and omphalocele often necessitates the administration of antireflux medication. Severe reflux and hiatal hernias require operative correction. Adhesive small bowel obstruction is a frequent occurrence in the first year following treatment of congenital abdominal wall defects, with previous sepsis and fascial dehiscence as predictive factors.[26]

Long-term follow-up shows function equal to that reported in age-related groups.

Patient Education

Patients should be counseled to avoid those activities that increase intra-abdominal pressure (eg, straining at defecation and lifting heavy objects). This may require restrictions on work or school-related activities, which should be clearly delineated. Patients should also receive instruction regarding ways of applying support to the hernia. Numerous medical device companies have developed support items that can assist with this process.

Even with asymptomatic hernias, repair at an early stage (ie, before the hernia enlarges) is preferred. Referral to a general surgeon for discussion of the available types of hernia repair is warranted; with the advent of new meshes and laparoscopic approaches, the range of repair options is now wider than ever.

 

Presentation

History

In an emergency setting, a patient with a hernia may present because of a complication associated with the hernia, or the hernia may be detected on routine physical examination. In most instances, the diagnosis of hernia is made because a patient, parent, or provider has observed a bulge in the inguinal region or scrotum (see the images below). This bulge is not necessarily constant but may be intermittent; depending on the intra-abdominal pressure, the herniating viscus may enter the space or remain outside it.

Large right inguinal hernia in 3-month-old girl. Large right inguinal hernia in 3-month-old girl.
Erythematous edematous left scrotum in 2-month-old Erythematous edematous left scrotum in 2-month-old boy with history of irritability and vomiting for 36 hours. Local signs of this magnitude preclude reduction attempts.

An asymptomatic hernia commonly has the following characteristics[27] :

  • Swelling or fullness at the hernia site
  • Aching sensation (radiating into the area of the hernia)
  • No true pain or tenderness upon examination
  • Enlargement with increasing intra-abdominal pressure or standing

In infants, the only symptom of a hernia may be increased irritability, especially when the hernia is large. Hernias in older children and adults may be accompanied by a dull ache or burning pain that often worsens with exercise or straining (eg, coughing). Neuralgia of the ilioinguinal nerve may present with a sudden stabbing pain in the distribution.

An incarcerated hernia may be associated with the following:

  • Painful enlargement of a previous hernia or defect
  • Inability to manipulate the hernia (either spontaneously or manually) through the fascial defect
  • Nausea, vomiting, and symptoms of bowel obstruction (possible)

A strangulated hernia may be associated with the following:

  • Symptoms of an incarcerated hernia, combined with a toxic appearance
  • Possibility of systemic toxicity secondary to ischemic bowel
  • Probability of strangulation if pain and tenderness of an incarcerated hernia persist after reduction

In patients who have a substantial amount of pain without evidence of incarceration or strangulation, an alternative diagnosis should be suspected.

Further anatomic considerations must be assessed in relation to the above clinical findings. The location of the underlying hernia may provide a unique constellation of symptoms, with or without specific anatomic findings, as follows:

  • Femoral hernia - Because of the position of this hernia, medial thigh pain is possible in addition to groin pain
  • Obturator hernia - Because this hernia is hidden within deeper structures, it may not present as a swelling; patients may complain of abdominal pain or medial thigh pain, weight loss, or recurrent episodes of bowel or partial bowel obstruction; pressure on the obturator nerve causes pain in the medial thigh that is relieved by thigh flexion but may be exacerbated by extension or external rotation of the hip (Howship-Romberg sign)
  • Incisional hernia - Because this hernia is usually asymptomatic, patients typically present with a bulge at the site of a previous incision; the lesion may become larger upon standing or with increasing intra-abdominal pressure

Physical Examination

In general, the physical examination should be performed with the patient in both the supine and standing positions, with and without the Valsalva maneuver. The examiner should attempt to identify the hernia sac, as well as the fascial defect through which it is protruding. This allows proper direction of pressure for reduction of hernia contents. The examiner should also identify evidence of obstruction and strangulation.

The first step in attempting to identify a hernia is to look for a swelling or mass in the area of the fascial defect. A fingertip is placed into the scrotal sac and advanced upward into the inguinal canal. If the hernia is elsewhere on the abdomen, an attempt should be made to define the borders of the fascial defect.

If the hernia comes from superolateral to inferomedial and strikes the distal tip of the finger, it most likely is an indirect hernia. If the hernia strikes the pad of the finger from deep to superficial, it is more likely to be a direct hernia. A bulge felt below the inguinal ligament is consistent with a femoral hernia.

Strangulated hernias are differentiated from incarcerated hernias by the following:

  • Pain out of proportion to examination findings
  • Fever or toxic appearance
  • Pain that persists after reduction of hernia

Inguinal hernia

Examination of an adult for an inguinal hernia is best performed from the seated position, with the patient standing. The inguinal canal areas for the bulge are visualized. A provocative cough may be necessary to expose the hernia; the cough is repeated as the examiner invaginates the scrotum and feels for an impulse. The diameter of the internal ring is assessed. Palpation of the cord structures is performed with the finger gently rolling perpendicular to the long axis of the cord just medial to the internal ring; this can detect thickening of the cord.

For examining a child, invagination of the scrotum is counterproductive because a hyperactive cremasteric muscle contraction reduces hernial contents into the peritoneum. In the subtle hernia of a child, palpation of the cord structures facilitates recognition of a thickened cord, particularly during straining, which can be easily prompted by tickling the child. A sensation of rubbing two layers of silk together (the so-called silk sign) may be felt.

If the hernia is not demonstrable in the supine position, the child should be examined in the upright position with intermittent manual pressure applied to the abdomen. If the examiner looks down at an angle from the infant’s chest level toward the groin, a combination of gravity and increased intra-abdominal pressure will inflate the open sac and thus confirm the hernia or hydrocele. The inguinal rings may be of normal size, even in children with very large hernias.

In a sliding inguinal hernia, a portion of a viscus or its mesentery constitutes part of the hernia sac. The bladder can be seen medially in the hernia sac, and portions of the colon (cecum on the right side, sigmoid on the left) may be part of any hernia sac. In females, the ovary or fallopian tubes may become part of the wall of the hernia sac and must be carefully preserved during repair.

If the visceral contents of a hernial sac cannot easily be reduced into the peritoneal cavity, the hernia is incarcerated. If the contents cannot be reduced at all, the hernia is irreducible. A solid mass with an almondlike feeling within the labia majora of a girl is usually an ovary, which is the most frequently incarcerated intra-abdominal organ in female infants.

As many as 15% of children, especially young infants, present with incarceration. Attempts at reducing an incarcerated hernia are often successful; 80% of children do not need an immediate operation. An emergency hernia operation has 20 times the risk of complications that an elective repair does; therefore, reduction of an incarcerated hernia should be attempted by an appropriately experienced practitioner, and conscious sedation should be used if necessary. In patients with chronic hernias, adhesions may hinder reduction.

Hydrocele

A hydrocele usually transilluminates on examination; however, gas-filled intestines also transilluminate, thus precluding diagnostic aspiration. If the scrotal size vacillates or the examiner can squeeze fluid from the sac into the peritoneum, a communicating hydrocele is present. Communicating hydroceles without an obvious hernia component should be repaired electively.

Hydroceles are considered insignificant if they are present at birth, bilateral, soft, and peritesticular; do not persist beyond 6 months; and do not fluctuate in size. Because most physiologic noncommunicating hydroceles resolve spontaneously, surgical treatment is generally confined to hydroceles that have persisted for longer than 1 year, those that develop communication, or those that appear painful to the child.

An acute hydrocele may present in childhood as a rapidly growing, painful scrotal swelling simulating an incarcerated hernia. Palpating the cord structures at the internal ring while assessing their mobility helps distinguish between these two entities. A hydrocele is more mobile, has a defined proximal margin, and is not thick. A hydrocele of the cord presents in the inguinal canal as a nontender, rubbery, round 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 or if the intra-abdominal component is causing a mass effect on other organs or obstructive symptoms.

Other hernia types

Hernias are the leading cause of intestinal obstruction in the world. Hidden hernias (eg, obturator, femoral, or lumbar hernias) should therefore be considered as possible causes of bowel obstruction. Intense pain is suggestive of strangulation with ischemic bowel. Torsion of the bowel on entry into the sac may lead to precipitous symptoms, whereas a more gradual onset of pain arises from progressive lymphatic, venous, and then finally arterial compromise secondary to occlusion at the neck of the sac.

Spigelian hernias present with local pain and signs of obstruction from incarceration. This pain increases with contraction of the abdominal muscles. Interparietal hernias between the layers of the abdominal wall present 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 intestinal symptoms or symptoms resembling those of a urinary tract infection. Vague flank discomfort combined with an enlarging mass in the flank suggests a lumbar hernia.

A testicular tumor is usually presumed when splenogonadal fusion presents as a scrotal mass. Recognition of splenic tissue on frozen-section examination eliminates the need for orchiectomy. A 2- to 4-mm mass of yellow-tan tissue found in 2.5% of hernia repairs is an ectopic adrenal rest. The proximity of the developing testis and the adrenal gland invites adherence of the two structures, 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 the following:

  • Incarcerated femoral hernia
  • Lymphadenopathy secondary to a variety of inflammatory or neoplastic processes
  • Soft-tissue tumor

Peritoneal signs and intestinal obstruction suggest an incarcerated femoral hernia. With common lymph node swelling, the mass is located superficial and inferior to the femoral ring. On examination, enlarged lymph nodes feel firm, somewhat lobulated, and fairly mobile. A primary lesion (eg, a cut, scratch, or open wound) should be sought through careful examination of the lymph node drainage area. Culture of the lymph node aspirate guides antibiotic therapy.

Cat-scratch disease lymphadenitis commonly develops in children. 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. Some 12% of cases are complicated by attendant symptoms of fever, malaise, myalgia, and anorexia; encephalitis; oculoglandular disease; and severe systemic disease. By 2 months, symptoms usually resolve spontaneously.

Infections such as toxoplasmosis, tularemia, infectious mononucleosis, actinomycosis, and HIV infection can also cause inguinofemoral adenopathy. In addition, some athletic individuals may have painful reactive inguinal or femoral lymph nodes as a consequence of repeated trauma.

Prevascular femoral hernia is rare and manifests as a bulge that 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. A hernia of Laugier traverses a defect in the lacunar ligament. A hernia of Cloquet results from an abnormal insertion of the pectineus, 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 hernias are characterized by intermittent, acute, and severe hyperesthesia or pain in the medial thigh or in the region of the greater trochanter. These manifestations are usually relieved by flexion of the thigh and worsened by medial rotation, adduction, or extension at the hip. Rarely, there is a palpable mass in the medial upper thigh.

A tender mass in the gluteal area that is increasing in size is suggestive of a sciatic hernia. Sciatic neuropathy and symptoms of intestinal or ureteral obstruction can also occur. Perineal hernias generally present as a perineal mass with discomfort on sitting; occasionally, they have obstructive symptoms with incarceration.

An umbilical hernia presents as a central, midabdominal bulge. Altered sensorium and obesity enhance the danger of incarceration. Hypertrophic, hyperpigmented, papyraceous skin testifies to high pressure being placed on the skin. The size of the fascial defect and whether it is circular provide management clues.

Diastasis recti (widened linea alba) is clinically insignificant, and operative repair is not required. However, there may be small openings in the linea alba through which preperitoneal fat can protrude. These epigastric hernias occur in children as well as in adults, suggesting congenital defects. Defects adjacent to the umbilicus are referred to as paraumbilical hernias, whereas more cephalad defects are called epiploceles or ventral hernias. These midline hernias present as lumps anywhere along the linea alba and tend to cause sudden severe pain with exercise.

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

Congenital abdominal wall defects

Maternal serum α-fetoprotein screening can help identify ventral wall defects in the fetus during the second trimester. Antenatal ultrasonography can define the location of the abdominal wall defect, the status of the viscera, the defect’s 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 until after delivery. This may result in compromise of the small bowel or damage to an omphalomesenteric duct as the cord is clamped. Therefore, in an infant with an unusual or widened umbilical cord base, the cord should be clamped well away from the abdomen to prevent iatrogenic injury to the intestine.

 

DDx

Diagnostic Considerations

History and physical examination remain the best means of diagnosing hernias. The review of systems should carefully seek out associated conditions, such as the following:

  • Ascites
  • Constipation
  • Chronic obstructive pulmonary disease
  • Cough
  • Groin abscess
  • Hematoma
  • Lipoma
  • Lymphadenitis
  • Obstructive uropathy
  • Pseudoaneurysm
  • Spermatocele
  • Tumor
  • Undescended or retracted testes
  • Varicocele

Differential Diagnoses

 

Workup

Approach Considerations

Laboratory studies are not specific for hernia but may be useful for general medical evaluation. Imaging studies are not required in the normal workup of a hernia[7, 8] ; however, radiography, computed tomography (CT), or ultrasonography may be considered in certain circumstances. Sigmoidoscopy is no longer recommended as a screening test.

Evaluation for potential reversal of provocative factors (eg, prostatism, chronic cough, severe constipation, rectal cancer, and ascites) is important.

Laboratory Studies

Laboratory studies that may be helpful include the following:

  • Stain or culture of nodal tissue - This can help diagnose atypical tuberculous adenitis
  • Complete blood count (CBC) - Results are nonspecific, but leukocytosis with left shift may occur with strangulation
  • Electrolyte, blood urea nitrogen (BUN), and creatinine levels - It is advisable to assess the hydration status of the patient with nausea and vomiting; these tests are rarely needed for patients with hernia except as part of a preoperative workup
  • Urinalysis - This can help narrow the differential diagnosis of genitourinary causes of groin pain in the setting of associated hernias
  • Lactate levels - Elevation may reflect hypoperfusion; a normal level does not necessarily rule out strangulation

Radiography

Plain radiographs taken tangentially may show air in the intestine outside the abdomen, as may contrast studies of the bowel. Unfortunately, visualization of the perineum and pelvis is poor with these studies. Higher yields can be obtained with dynamic changes in position, intra-abdominal pressure, or both during the imaging studies. Better assessments of the perineum and pelvis are possible via external views of the intestine and their domain with herniography.

Careful instillation of water-soluble nonionic contrast through the abdominal wall helps to define most hidden hernias, such as interparietal, pelvic, obturator, sciatic, and other poorly palpable hernias (eg, small recurrent hernias).[28] However, unintentional luminal contrast injection may lead to infection.

If an incarcerated or strangulated hernia is suspected, the following imaging studies may be helpful:

  • Upright chest radiograph to exclude free air (extremely rare)
  • Flat and upright abdominal films to diagnose a small bowel obstruction (neither sensitive or specific) or to identify areas of bowel outside the abdominal cavity

Computed Tomography

CT of the abdomen and pelvis with oral and intravenous (IV) contrast can help detect many elusive hernias by demonstrating extracoelomic location of the bowel, bladder, or female internal reproductive organs.[29] CT may be indicated in the diagnosis of a spigelian or obturator hernia and in cases where the patient’s body habitus makes it difficult for the physician to perform a good physical examination.

Ultrasonography

Ultrasonography is helpful in narrowing the differential on both scrotal masses and masses below the inguinal ligament. It can also aid in the decision to drain or aspirate a nodal abscess. Like CT, ultrasonography may be indicated when a spigelian or obturator hernia is suspected or when the patient’s body habitus hinders physical examination.

Infants with omphaloceles require prompt, thorough evaluations to detect associated anomalies. Initial studies should include bilateral renal ultrasonography and echocardiography, as well as karyotyping and plain radiography of the sacrum.

Histologic Findings

Pathologic evaluation of pediatric hernia sacs offers little relevant clinical information. Tubular structures found during pathologic examination may indicate aberrant ductuli of Haller or duplications instead of segments of the vas deferens. Ductuli are 50-100 µm in size, much smaller than even the infant vas deferens; duplications can be proved only through reexploration.

 

Treatment

Approach Considerations

Trusses place pressure on the skin and bowel, induce related injury, and mask signs of incarceration and strangulation. The temporary use of binders or corsets can be useful in patients with large-necked hernias, during the preoperative period, or in situations where there is a high risk of operation on a long-term basis.

Hernia reduction or repair may be carried out, depending on the type of hernia and on whether incarceration is present (see below). Reduction can often be carried out in the emergency department (ED), but a surgeon should be consulted for the following reasons[30, 6] :

  • Inability to reduce the hernia
  • Concern for a strangulated bowel and a patient with a toxic appearance; all incarcerated or strangulated hernias demand admission and immediate surgical evaluation
  • Comorbid risks for sedation; patients with such risks should have a surgeon present for the initial reduction attempt

Surgical options depend on the type and location of the hernia.

Inguinal hernia

In general, the presence of an inguinal hernia, in the absence of mitigating factors, constitutes an indication for repair to prevent the complications of prolonged exposure (eg, incarceration, obstruction, and strangulation).[31] Although pressure reduction of an incarcerated hernia is generally safe, failure to reduce is not infrequent and mandates prompt exploration.

Signs of inflammation or obstruction should rule out attempts at reduction. Difficult reduction should promptly be followed by repair. Unintentional reduction of the intestine with vascular compromise leads to perforation and peritonitis with high morbidity and mortality. En masse reduction after vigorous attempts at reducing a hernia with a small fibrous neck results in ongoing compromise of the entrapped bowel.

Umbilical hernia

In adults, umbilical hernia repair is indicated for incarceration, a small neck in relation to the size of the hernia, ascites, chromatic skin change, or rupture. In children, the approach to managing an umbilical hernia is related to the natural history of umbilical hernias and their importance in adulthood.

Most umbilical hernias close spontaneously in children during the preschool-age period. Therefore, repair of an umbilical hernia is not indicated in children younger than 5 years unless the child has a large proboscoid hernia with thin, hyperpigmented skin or is undergoing an operation for other reasons or if the hernia causes familial or social problems.

It is the size of the fascial defect, rather than the size of the external protrusion, that predicts the potential for spontaneous closure. Walker demonstrated that fascial rings measuring less than 1 cm in diameter usually close spontaneously, whereas rings larger than 2 cm seldom do.[22] Accordingly, many pediatric surgeons will repair umbilical hernias with large (>2.5 cm) fascial defects earlier than hernias with smaller fascial defects.

Incarceration of umbilical hernias is rare in the pediatric population. Over a 15-year period, only seven children with an incarcerated umbilical hernia were reported at the Johns Hopkins Hospital. In comparison, 101 cases of umbilical hernia incarceration occurred in adults at that institution during the same 15-year period. Omentum is the most frequently incarcerated organ.

Other hernia types

Painful preperitoneal fat in an epiplocele or paraumbilical hernia may be incarcerated. Because these defects will not close spontaneously and a propensity exists for painful strangulation, elective outpatient repair is recommended.

Because of the potential for incarceration, spigelian hernias should be repaired, as should interparietal, supravesical, lumbar, obturator, sciatic, and perineal hernias. Notably, strangulation can occur in a Richter hernia without evidence of incarceration or obstruction.

Elective vs acute repair

A retrospective, single-institution study reported that patients with femoral, scrotal, and recurrent hernias, as well as patients of advanced age, are more likely to undergo acute hernia repair versus elective hernia repair.[32] Acute hernia repair reportedly has a higher morbidity and lower survival rates than elective hernia repair does.

Contagious disease, diaper rash, nearby open wounds, an upper respiratory tract illness, or other intercurrent illness should delay an elective procedure; other delays probably increase the risks of operative complications. In cases where the risk of operation exceeds that of potential problems from the hernia, nonoperative observation is wise.

Hernia Reduction

In attempting hernia reduction, the first step is to provide adequate sedation and analgesia so as to prevent straining or pain.[1, 5, 33] The patient should be relaxed enough that he or she will not increase intra-abdominal pressure or tighten the involved musculature.

The patient should be supine, with a pillow under the knees. For an inguinal hernia, the patient should be placed in a Trendelenburg position of approximately 15-20°. The ipsilateral leg is placed in an externally rotated and flexed position resembling a unilateral frog leg position. A padded cold pack may be applied to the area to reduce swelling and blood flow while appropriate analgesia is established. Ice cooling of an incarcerated hernia is counterproductive.

Simple pressure over the distal sac usually is ineffective, in that the incarcerated viscera are likely to mushroom over the external ring (see the first image below). Instead, two fingers are placed at the edge of the hernial ring, and firm, steady pressure is applied to the side of the hernia contents close to the hernia opening and maintained for several minutes while the hernia is being guided back through the defect (see the second image below).

Hernia content balloons over external ring when re Hernia content balloons over external ring when reduction is attempted.
Hernia can be reduced by medial pressure applied f Hernia can be reduced by medial pressure applied first.

In children, pressure should be applied from the posterior and directed laterally and superiorly through the external ring. It should be kept in mind that the internal ring in infants is more medial than the internal ring in older children and adults. The hourglass configuration of a hernia -hydrocele complex will not reduce with pressure applied to the hydrocele portion.

If success is not achieved after one or two attempts at reduction, a surgeon should be consulted; repeated forceful attempts are contraindicated. Pain after a successful reduction may indicate a strangulated hernia, necessitating further evaluation by a surgeon.

The spontaneous reduction technique requires adequate sedation and analgesia, Trendelenburg positioning, and padded cold packs applied to the hernia for 20-30 minutes. This can be attempted before manual reduction attempts.

Topical Therapy

Cauterization with silver nitrate aids in the resolution of an umbilical granuloma. If there is a stalk, ligation of the base resolves the problem. Delaying the repair of umbilical or asymptomatic epigastric hernias until children are older than 5 years allows spontaneous closure in most children. Strapping, with or without a coin, is not indicated in the treatment of umbilical hernia, because of problems with skin erosion and lack of effectiveness.

Grob introduced the use of merbromin 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 (which has leukopenia as a complication), povidone-iodine solution (hypothyroidism as a complication), 0.5% silver nitrate solution (argyrism as a complication), and gentian violet have served as agents to protect against infection while the sac epithelializes.

In current practice, only life-threatening associated conditions, poor probability of survival in infants, or failure of better means of coverage warrant use of these methods. 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 dressing of a self-adhesive compression bandage can reduce viscera over 5-10 days, after which time delayed primary fascial and skin closure is accomplished.

For children with an omphalocele and life-threatening associated conditions, a poor probability of survival, or a very large omphalocele, the combination of topical escharotic agents and daily abdominal wrapping with an elastic bandage has produced successful closure in many patients.

As the child grows, the defect remains the same size and becomes smaller relative to the increasing abdominal wall. Delayed closure following epithelialization can allow primary fascial closure with no prosthesis, which eliminates the need for multiple operations. External coverage with pigskin, skinlike polymer membrane, or human amniotic membrane can be used adjunctively in the treatment of giant omphalocele or after failed primary therapy.

Surgical Repair of Inguinal Hernia

The fundamentals of indirect inguinal hernia repair are basically the same, regardless of the 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 sufficiently attenuated as to preclude following these precepts, many techniques involving the release of tension by flaps, prosthetic materials, or a simple relaxing incision in adjacent tissue will fulfill the requirements. Overlay, underlay, and sandwiching of the edges with plastic meshes constitute most techniques today.

Return to work is dictated by the approach and the amount of physical activity involved with the job. Accurate postoperative instruction and easy access to care (if problems arise) are as effective as a full postoperative visit following routine inguinal hernia repairs.

Basic repair techniques

Bassini and Shouldice repairs

The essence of the Bassini repair is apposition of the transversus abdominis, transversalis fascia, and lateral rectus sheath to the inguinal ligament. This is usually performed by imbrication (see the image below). The Shouldice technique uses two layers of continuous suture in a similar fashion.

Bassini-type repair approximating transversus abdo Bassini-type repair approximating transversus abdominis aponeurosis and transversalis fascia to iliopubic tract and inguinal ligament.

Cooper repair

The Cooper repair approximates the conjoint area, transversus abdominis, and transversalis fascia to the pectineal (Cooper) ligament. Overlying the vein, these structures are sewn to the iliopubic tract. This technique also provides a good approach for the repair of femoral hernias.

Tension-free mesh repairs

The standard adult hernia repair now uses prostheses to reinforce the floor, usually polypropylene mesh. The material can overlay, underlay, or sandwich the area or can be used as a plug. This provides a tension-free repair and excellent results, but it carries a slightly increased risk of wound infection. The Lichtenstein hernioplasty is currently one of the most commonly performed mesh-based tension-free repairs (see Open Inguinal Hernia Repair).

The preperitoneal approach has advocates who claim that this approach makes it easier to identify the sac, reduce the contents, and dissect the cord structures. Mechanical advantages include the use of natural intra-abdominal pressure to keep the mesh in place over all potential hernia sites. The best uses are in the repair of hernias incidentally encountered during other abdominal procedures, recurrent hernias, and femoral hernias.

A Pfannenstiel, lower midline, or other incision is used to reach the preperitoneal plane. The internal inguinal ring and the hernia sac are identified lateral to the inferior epigastric vessels. After the sac is dissected from the testicular vessels and vas deferens, it is divided and the peritoneum closed. The repair follows the pectineal approach and often has mesh applied.

Simple repair for pediatric hernias

A simple inguinal hernia repair is possible in children because of the smaller size, better muscle tone in the canal, and rapid recuperation. Excision of the hernial sac (processus vaginalis) is usually sufficient, with little need for prosthetic repair of an attenuated internal ring or posterior wall of the inguinal canal. Either preincisional injection of the incision site or a caudal block is preferable to no preincisional therapy.[34]

A small incision is made just superior and lateral to the pubic tubercle in the suprapubic skin crease, centering the operative field near the internal ring. The external oblique aponeurosis is incised in the direction of its fibers, or the internal and external rings are transposed by laterally retracting the latter. Tugging on the testis helps visualize cord structures. The glistening white hernia sac often bulges up amid the cord. The sac, located anteromedial to the cord, is elevated from the floor and carefully dissected free from the vas deferens and testicular vessels.

Short hernia sacs are freed to the internal ring, but long sacs are often best divided. Proximal dissection to the internal ring should extend until preperitoneal fat is visible circumferentially. Twisting the sac before ligation provides strength and narrows the internal ring. The sac is ligated at its base. Because of occasional postoperative “spitting” of a nonabsorbable (eg, silk) suture, 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. 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 the image below).

Iatrogenic cryptorchid testis in child. Taking car Iatrogenic cryptorchid testis in child. Taking care to position testis in scrotum is integral part of completion of hernia repair in boys.

Approximately 2% of girls with inguinal hernias have an intersex differentiation syndrome. Each girl should have the fallopian tubes and ovaries examined directly or via 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 of this is testicular feminization (androgen insensitivity) syndrome, which results from end-androgen resistance and leads to 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, a gonadectomy on one side and isolation of 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.

An incarcerated object within an inguinal hernia in a girl, especially in an infant, is usually an ovary. An incarcerated ovary is not usually reducible, but strangulation is infrequent, making surgical reduction of the irreducible ovary less urgent than reduction of an incarcerated intestine would be. A child with an incarcerated hernia containing the intestine that successfully is reduced should be admitted for 1 day to allow resolution of edema before repair.

A child with tachycardia, fever, or signs of obstruction must be operated on immediately. 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.

Exposing and opening the sac before dividing the external ring permits the contained intestine to be controlled with a clamp, preventing unintentional release of the bowel into the abdomen. Once the viability of the incarcerated intestine is ensured, dividing the external ring (and sometimes the internal oblique muscles) laterally will reduce it.

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

Laparoscopic repair techniques

Laparoscopic techniques are increasingly being used to repair both primary hernias and recurrent hernias (see Laparoscopic Inguinal Hernia Repair). The totally extraperitoneal (TEP) approach is usually favored over the transabdominal preperitoneal (TAPP) approach because of the complications that arise from exposed intraperitoneal mesh in the latter. Postoperative pain, time to full recovery, and return to work are improved with the laparoscopic approach, but it is more expensive. Short-term recurrence data are comparable so far.

For most abdominal wall hernias, laparoscopic repair probably represents the future.[35] As the cost of instrumentation decreases, procedure-specific instrument design improves, and the laparoscopic learning curve is obliterated, the saying “if all else is equal, less pain and better cosmesis win out” will hold true. For example, prospective studies out of Europe found laparoscopic repair of pediatric hernias to be comparable to the results of open surgery.[36] The use of new materials or techniques may alter the approach.[37]

In a retrospective cohort study of 79 patients who underwent laparoscopic repair of primary ventral hernias and 79 who underwent open hernia repair, patients with a laparoscopic ventral hernia repair were significantly less likely to develop a surgical site infection (7.6% vs 34.1%). However, patients who underwent laparoscopic repair were more likely to develop a postoperative ileus (10.1% vs 1.3%), to have a persistent bulge at the operative site (21.5% vs 1.3%), and to have a longer hospital stay.[38, 39]

Treatment approach

Adults

After a diagnosis is established, the signs, symptoms, and risks of incarceration, as well as the timing, conduct, and risk of the repair procedure, should be explained to the patient or caregiver. Most repairs proceed within several weeks, with the precise timing dependent on multiple factors (eg, employment and insurance).

With massive hernias, prosthetic material is usually needed to aid closure, and appropriate materials should be available in the operating room before incision. 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.

Adults with very large chronic hernias should be admitted postoperatively because of the combination of ileus from extensive manipulation and loss of domain with the attendant problems of increased pressure on the diaphragm, vena cava, kidneys, and hernia closure. Adults who present with bilateral hernias without the need for formal reconstruction can undergo simultaneous repair; more complex procedures require the repairs to be separated by at least 1 month.

Local anesthesia is sufficient for most repairs in adults; however, prolonged procedures, repair of hernias with a large intraperitoneal component, including laparoscopy, and repair of recurrent hernias are best managed with spinal, epidural, or general anesthesia.

Routine preoperative antibiotic prophylaxis is not currently recommended for low-risk adults undergoing a standard tension-free mesh-based repair; multiple studies have shown this practice to be of no benefit in decreasing postoperative wound infection.

Patients undergoing a neurectomy have a significantly lower prevalence of neuralgia without increased paresthesia.

Children

In healthy full-term infant boys with asymptomatic reducible inguinal hernias, regardless of age or weight, pediatric surgeons typically carry out repair soon after diagnosis.[20] In full-term girls with a reducible ovary, most surgeons operate at a close elective date, but more urgent scheduling of surgery is preferred if the ovary is not reducible but asymptomatic.

Premature infants with inguinal hernias usually undergo repair before being discharged from the neonatal intensive care unit (NICU), but this practice is changing, and infants are now being discharged home at much lower weights. Some surgeons prefer to postpone the surgery in these very small babies for 1-2 months to allow further growth.

All children with a bilateral presentation should undergo bilateral inguinal hernia repair under a single anesthesia. However, there remains some controversy regarding the correct approach to exploration of the contralateral side in pediatric inguinal hernias.[40] The potential damage to the spermatic cord structures in boys and the low incidence of contralateral hernia development in infants (< 1 year) and older children argue against routine contralateral groin exploration.[41, 42]

The previous practice of routinely exploring the opposite side in all boys younger than 2 years and all girls younger than 4-5 years is no longer popular. Most surgeons do not routinely perform open exploration of the contralateral groin, except in cases of high anesthetic risk, significant risk for developing contralateral hernia secondary to increased intra-abdominal pressure, or limited access of the child to appropriate medical care should an incarceration occur on the opposite side.

Current practice in many pediatric centers uses peritoneoscopy through the ipsilateral inguinal sac to identify contralateral patent processes and hernias.[43] Long-term follow-up is needed because only 20% of the patent processes identified become clinically apparent hernias in the short term.

A surgeon who is unfamiliar with the tissue characteristics and metabolic and psychological needs of children or who does not have a skilled pediatric anesthesiologist available should not attempt a hernia operation in a young child. Older children usually have general inhalation anesthesia, whereas some 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.

Routine use of perioperative antibiotics for uncomplicated inguinal hernia repairs in children is not generally indicated. Some cardiologists advise prophylactic antibiotic use to lower the risk of endocarditis in children with associated cardiac defects; patients with ventriculoperitoneal shunts may also benefit.

Postoperative apnea is common in premature infants.[44] Those younger than 50 weeks’ gestational age should be admitted for 24 hours postoperatively and placed on a cardiorespiratory monitor.[45, 46, 47]

Sliding hernia

In about 40% of girls with an inguinal hernia, the fallopian tube (or, occasionally, the ovary or uterus) is a sliding component of the hernia that cannot be easily reduced into the abdominal cavity. The sac wall may seem too thick in the medial or lateral quadrants, or the contained viscus (particularly the fallopian tube and ovary) may not be reducible into the peritoneum. The walls must then be inspected for a sliding component.

To repair a sliding hernia, the sac is ligated distal to the fallopian tube and divided. The proximal sac is ligated and then invaginated into the peritoneal cavity. A purse-string suture inside the opened hernia sac may be used to aid in visualization during sac closure. The internal ring is closed with sutures from the transversalis fascia to the iliopubic tract.

Surgical Repair of Other Hernia Types

Masses in femoral canal

Atypical tuberculous adenitis is best treated by means of local excision. Repeated trauma may cause painful reactive inguinal or femoral lymph nodes. Excision of the involved node relieves symptoms. The potential for malignancy in a femoral canal mass that persists despite antibiotic therapy warrants biopsy. Any enlarged lymph node that is excised should be divided, with one half sent fresh for lymphoma protocol and the other half sent to microbiology. A suspected femoral hernia, usually after a missed inguinal hernia repair, also warrants exploration.

The best approach for both adenopathy and femoral hernia is a preperitoneal approach. Reduction of an incarcerated intestine is easy, and there is clear access to the lymph node. 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.

Umbilical hernia

In children, umbilical hernia repair is best performed with general anesthesia, whereas in adults, regional or local anesthesia can be used. A semicircular incision in the infraumbilical skin crease exposes the umbilical sac. A plane that is created to encircle the sac at the level of the fascial ring expedites repair. The defect is closed primarily in a transverse direction with a single layer of interrupted sutures. If the defect is very large, mesh is occasionally required.

Although excessively wrinkled skin can appear cosmetically troublesome, elasticity and growth usually corrects the problem because the skin incision lies within the umbilical fold. In cases with severe redundant skin, removal of a circle of skin and peritoneum to access the hernia, followed by a purse-string closure, provides an excellent cosmetic result. A pressure dressing is applied for several days after repair.

Epigastric hernia

Immediately before the operation, the defect should be marked with the patient standing. After anesthetic induction, a small vertical incision directly overlying the defect is carried to the linea alba. Incarcerated preperitoneal fat may be either excised or returned to the properitoneum. The edges of the fascial defect are approximated transversely with interrupted sutures. Recurrence is rare, though a second epigastric hernia may develop elsewhere as a separate defect.

Spigelian hernia

Despite being rare and difficult to diagnose, spigelian hernias are easily approached. A transverse incision over the hernia to the sac allows dissection to the neck, and clean approximation of the internal oblique muscle and transversus abdominis completes the repair. Laparoscopic repair allows accurate delineation of the anatomy and helps establish the diagnosis in suspect instances.

Interparietal hernia

Because most interparietal hernias are associated with an undescended testis, the spermatic cord should be identified. In a young child, an orchiopexy is performed if the testis is not gangrenous; in an older child or adult, the testicle should be removed. For the usual presentation of bowel incarceration, a properitoneal indirect inguinal hernia repair is the best approach.

Supravesical hernia

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

Lumbar hernia

A lumbar hernia is best approached with the patient in the lateral decubitus position and with the use of 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.

Obturator hernia

Obturator hernias are approached abdominally and can be repaired laparoscopically. If the hernia content is difficult to reduce, incision of the obturator membrane at the inferior margin will lessen damage to the obturator vessel or nerve. Mesh closure is necessary for a tension-free repair. The other side must be viewed to preclude problems with a contralateral hernia.

Sciatic hernia

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

A transgluteal repair can be used if the diagnosis is established and the intestine is clearly viable. The patient is placed prone, and the incision is extended from the hernia toward the greater trochanter. The fibers of the gluteus maximus are spread to expose the piriformis, the gluteal neurovascular bundle, and the sciatic nerve. A prosthetic patch closes the defect between the piriformis and the iliac or ischial bone.

Perineal hernia

A transabdominal approach with prosthetic closure is the preferred approach in the repair of perineal hernias.

Surgical Repair of Gastroschisis, Omphalocele, and Other Defects

Gastroschisis and omphalocele

The morbidity and mortality associated with omphalocele or gastroschisis in infants over the past 35 years has greatly decreased because of better preoperative and postoperative care. Specifically, these improved outcomes are secondary to advances in neonatal ventilator care and the development and use of total parental nutrition during the period of transition to normal bowel function.

Patients with syndromic omphaloceles have had only modest increases in mortality secondary to the unchanged severity of their associated defects. The improvement in this population results from prenatal recognition, earlier prenatal transport to pediatric surgical referral centers, and enhanced perioperative care.

Perioperative considerations

The greatest loss of contractility and mucosal function of the bowel and the fibrous coating of the bowel in gastroschisis occurs late in gestation. Delivery of infants with prenatally diagnosed abdominal wall defects can be via vaginal or cesarean delivery; neither method has a clear advantage over the other.

Preterm induction after ensuring lung maturity may be advantageous in cases of gastroschisis where serial imaging of the bowel reveals increasing dilation suggestive of a restrictive defect. To avoid damage to the sac from labor and delivery, elective preterm cesarean section is no longer recommended for infants with large omphaloceles.

Placing the infant up to the axillae in a sterile plastic bag maintains sterility, prevents evaporative water loss, and decreases heat loss. Infants with gastroschisis can be placed on their right side until silo placement is complete to prevent vascular compromise from twisting or kinking of the fascial edge. Although recommendations in the literature vary, the trend is toward universal silo placement and gradual reduction. Broad-spectrum antibiotics should be given, most commonly ampicillin and gentamicin.

The inflamed peritoneal and intestinal capillary membranes stabilize in 12-18 hours after surgery, 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. The testes may be extracorporeal and should be placed near the processus vaginalis, because testicular proximity is a critical factor in the formation of the gubernaculum.

Management approaches

The major challenges in gastroschisis are reduction of the inflamed viscera into the abdomen and maintenance of effective nutrition. The two major problems in the management of omphaloceles are (1) closure of the defect without undue tension and (2) treatment of associated anomalies, particularly cardiac defects and pulmonary hypoplasia. Associated anomalies must be stabilized swiftly before operation.

Primary closure of fascia and skin is the best approach for omphalocele and gastroschisis. However, increased intra-abdominal pressure from immediate reduction can compromise ventilation and lead to abdominal compartment syndrome with inferior vena caval compression, intestinal and renal hypoperfusion, and lower-extremity edema.

Enlargement of the abdominal cavity by stretching the abdominal wall, decompression of the stomach and irrigation of the intestine and colon to remove meconium, and postoperative use of ventilators and muscle relaxants frequently can facilitate successful primary closure. The sac is removed at the fascial edge. Umbilical artery 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.

Nonoperative management of gastroschisis, also known as plastic closure, is an alternative to conventional primary operative closure or staged silo closure. Although it is considered safe, nonoperative management is nonetheless associated with an increased incidence of umbilical hernias.[48]

Intra-abdominal pressure measurements help prevent intra-abdominal compartment syndrome. Excessively high pressures mandate immediate conversion to a Silon chimney sutured to the skin or the fascial rim (see the image below). The gradual reduction of liver and intestine represents an improvement over previous methods, and most pediatric surgeons use this technique. Fascial and skin closure occurs after complete reduction of contents into the abdomen, which usually occurs over 3-7 days.

Infant with Silon chimney placed in treatment of g Infant with Silon chimney placed in treatment of gastroschisis.

An alternative technique for omphaloceles is abdominal binding. With sequential pressure, the viscera can be reduced into the abdomen over a similar period, followed by delayed primary closure. During final abdominal closure, a prosthetic patch of expanded polytetrafluoroethylene (ePTFE) or biosynthetic mesh can bridge the gap between the rectus muscles. Tissue expanders can facilitate this stage.[49] Orchiopexy can be performed for cryptorchid testes at the time of final closure.

Intestinal atresia is common. Anastomosis at the closure operation is sometimes possible, depending on the degree of bowel thickening. Repair after a 4- to 6-week period of bowel decompression and parenteral nutrition is preferable, but this is contraindicated in the face of a large proximal-distal discrepancy or necrotic intestine. The combination of stomas and prosthetic material can be avoided in almost all patients.

Beckwith-Wiedemann syndrome

The diagnosis of Beckwith-Wiedemann syndrome should be suspected in a large neonate with macroglossia. As these infants are at risk for severe hypoglycemia, close monitoring and early administration of glucose can prevent the serious sequela of hypoglycemia.

Pentalogy of Cantrell

Pentalogy of Cantrell is a malformation of the upper abdominal fold characterized by an anterior diaphragmatic and pericardial defect, a short bifid sternum, and cardiac defects associated with an epigastric omphalocele sac or hypotrophic epigastric skin. Temporary coverage of the omphalocele during evaluation of the cardiac defects will allow subsequent complete repair of cardiac, diaphragmatic, and pericardial defects.

Vesicointestinal fissure or cloacal exstrophy is a malformation of the lower fold defined by an inferiorly 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 occasional meningosacral anomalies. These infants can survive after 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. About 50% of children with external mucosal remnants will have an additional component within the abdomen. Urachal remnants should be excised locally at the umbilicus and followed caudally for a short distance toward the dome of the bladder, where they should be sutured, ligated, and divided.

Long-Term Monitoring

For patients with easily reducible hernias or with hernias found upon physical examination, follow-up visits with the general surgeon should be scheduled within the 1-2 weeks following the procedure. Patients with umbilical hernias may be discharged with close follow-up care if the defect is less than 2 cm in diameter and the hernia is not incarcerated or strangulated.

Accurate postoperative instruction and easy access to care (if problems arise) are as effective as a full postoperative visit after routine inguinal hernia repairs. Patients should be educated to avoid those activities that increase intra-abdominal pressure and instructed to return if they note an irreducible hernia, increased pain, fever, or vomiting.

 

Guidelines

IEHS Guidelines on Laparoscopic Treatment of Ventral/Incisional Abdominal Hernia

In July 2019, the International Endohernia Society (IEHS) published updated guidelines regarding laparoscopic treatment of ventral and incisional abdominal wall hernias.[50]

Hernia with diastasis recti

Mesh reinforcement of ventral hernia repairs with a concomitant rectus diastasis is recommended.

In laparoscopic intraperitoneal onlay mesh (IPOM) repair of ventral hernia and concurrent rectus diastasis, reconstruction of the linea alba with mesh augmentation should be performed when possible.

Several endoscopic, laparoscopic, and robotic options for extraperitoneal mesh repair of ventral hernia with concomitant rectus diastasis can be offered. Ongoing evaluation is needed.

Patients with significant diastasis and associated functional impairment should be offered surgical repair.

Component separation techniques

Component separation (CS) techniques (CST) should be used to obtain fascial closure in large midline  hernias. CST should be used in combination with mesh reinforcement whenever possible. CST should be considered to obtain fascial closure in contaminated fields, when no mesh is used.

With regard to anterior CST preferences, for fascial closure of large midline hernias, surgeons should consider endoscopic anterior CS (EaCS) or minimally invasive anterior CS (MIaCS) as an alternative to open anterior CS (OaCS) in order to reduce postoperative wound morbidity.

For intermediate-to-large defects, surgeons should consider EaCS, MIaCS, or transversus abdominis release (TAR) as an alternative to OaCS in order to reduce postoperative wound morbidity. For lateral defects in need of a large mesh overlap, TAR should be preferred to anterior CST.

Transversus abdominis release

TAR can be applied for abdominal wall reconstruction to achieve restoration of the midline in complex ventral hernias (M1-5, W3); for recurrent hernias following previous anterior CS; and for lateral hernia repair (L1-4).

TAR can be open, laparoscopic, or robotic.

Preoperative adjunct interventions

No recommendati­ons can be made regarding the use of botulinum toxin A, progressive pneumoperitoneum, or ti­ssue expanders as adjuncts in ventral hernia repair.

Robotic ventral/incisional hernia repair

Roboti­c IPOM (rIPOM) may be considered comparable to standard laparoscopic ventral hernia repair with intraperitoneal mesh (LVHR) in most clinical outcomes, at the expense of increased opera­ting time. Data are insufficient to allow adequate comparison of recurrence risk. Hospital length of stay (LOS) may be reduced with rIPOM. rIPOM improves the ability to close the hernia defect during minimally invasive hernia repair.

Robotic transabdominal preperitoneal repair (rTAPP) is a safe and effecti­ve alternati­ve to rIPOM or standard IPOM LVHR for small hernias. rTAPP allows placement of mesh in an extraperitoneal positi­on, which may reduce long-term mesh-related complicati­ons.

Significant reduction in LOS is possible with robotic retromuscular ventral hernia repair (rRVHR) or robotic TAR (rTAR) and should be considered in patients with ventral/incisional hernias.

Reduction in surgical-site infection (SSI) may be achieved with rVHR, rTAR, or robotic extended totally extraperitoneal (eTEP) repair; larger studies are necessary for further assessment.

Recurrence rates appear similar to those of open ventral hernia repair (OVHR) and LVHR, but long-term follow-up is lacking.

Robotic eTEP may reduce the need for additional myofascial release as compared with rTAR, thus more closely approximating the stepwise approach to myofascial release performed in OVHR.

Lateral primary or incisional hernia

Open and laparoscopic mesh techniques can be recommended for the treatment of primary and incisional hernias of the lateral abdominal wall.

Large lateral abdominal wall hernias (defect diameter >15 cm) should be treated via an open approach.

Spigelian hernia

For the treatment of spigelian hernias, laparoendoscopic mesh repair should be preferred because of lower postoperati­ve morbidity and reduced hospital LOS.

 

Medication

Medication Summary

For strangulated hernias, broad-spectrum antibiotic therapy should be initiated. Antibiotics are administered routinely if bowel ischemia is suspected.

Antibiotics

Class Summary

Antibiotics are to be used if the patient has a strangulated hernia. Broad-spectrum antibiotics, most commonly ampicillin and gentamicin, should be given in cases of gastroschisis and patients with large omphalocele.

Cefoxitin (Mefoxin)

Multiple regimens that address bowel perforation or ischemic bowel can be used. Cefoxitin provides coverage for both aerobic and anaerobic gram-negative bacteria.

Gentamicin

Gentamicin is an aminoglycoside antibiotic used for gram-negative bacterial coverage. It is commonly used in combination with an agent against gram-positive organisms and one that covers anaerobes. The drug is used in conjunction with ampicillin for prophylaxis in patients with open surgeries.

Dosing regimens are numerous and are adjusted based on creatinine clearance (CrCl) and changes in volume of distribution. Gentamicin may be given intravenously or intramuscularly.

Ampicillin

Ampicillin is used along with gentamicin for prophylaxis in patients with open surgeries. It interferes with bacterial cell wall synthesis during active replication, causing bactericidal activity against susceptible organisms.

Local Anesthetics

Class Summary

Local anesthetic agents are used to increase patient comfort during the procedure.

Lidocaine and epinephrine (Lignospan Forte, Xylocaine with Epinephrine)

Lidocaine is an amide local anesthetic used in a 0.5-1% concentration in combination with bupivacaine (50:50 mixture). This agent inhibits depolarization of type C sensory neurons by blocking sodium channels. Epinephrine prolongs the duration of the anesthetic effects from lidocaine by causing vasoconstriction of the blood vessels surrounding the nerve axons.

Bupivacaine (Marcaine, Sensorcaine)

Bupivacaine 0.25% may be used in combination with lidocaine plus epinephrine (50:50 mixture). It decreases permeability to sodium ions in neuronal membranes. This results in the inhibition of depolarization, blocking the transmission of nerve impulses.

General Anesthetics

Class Summary

After standard monitoring equipment is attached and peripheral venous access achieved but before the arterial line is inserted, the midazolam or lorazepam dose is administered.

Propofol (Diprivan, Fresenius Propoven)

Propofol is a phenolic compound unrelated to other types of anticonvulsants. It has general anesthetic properties when administered intravenously. Propofol IV produces rapid hypnosis, usually within 40 seconds. The effects are reversed within 30 minutes following the discontinuation of infusion. Propofol has also been shown to have anticonvulsant properties.

Thiopental

Thiopental is a short-acting barbiturate sedative-hypnotic with rapid onset and a duration of action of 5-20 minutes. Like methohexital, it is most commonly used as an induction agent for intubation. To use thiopental as a sedative, titrate in dosage increments of 25 mg (adjust to lower dose in children).

Antianxiety Agents

Class Summary

These agents are indicated for patients who may experience significant anxiety before a surgery.

Lorazepam (Ativan)

Lorazepam is a sedative-hypnotic of the benzodiazepine class that has a rapid onset of effect and a relatively long half-life. By increasing the action of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter, it may depress all levels of the central nervous system (CNS), including the limbic system and reticular formations. Lorazepam is excellent for patients who need to be sedated for longer than 24 hours.

Midazolam

Midazolam is a sedative-hypnotic of the benzodiazepine class that provides initial sedation as well as amnesia.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Class Summary

These agents have analgesic, anti-inflammatory, and antipyretic properties. Their mechanism of action is not known but may inhibit cyclo-oxygenase (COX) activity and prostaglandin synthesis. Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell membrane functions.

Diclofenac (Voltaren-XR, Cataflam, Zipsor, Cambia)

Diclofenac inhibits prostaglandin synthesis by decreasing COX activity, which, in turn, decreases the formation of prostaglandin precursors.

Ibuprofen (Advil, Ultraprin, I-Prin, Motrin IB)

Ibuprofen is the drug of choice for patients with mild to moderate pain. It inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.

Sulindac (Clinoril)

Sulindac decreases the activity of COX and, in turn, inhibits prostaglandin synthesis. Its action results in the decreased formation of inflammatory mediators.

Naproxen (Anaprox, Aleve, Naprosyn, Naprelan)

Naproxen is used for the relief of mild to moderate pain. It inhibits inflammatory reactions and pain by decreasing the activity of the enzyme COX, which results in prostaglandin synthesis.

Meloxicam (Mobic)

Meloxicam decreases COX activity and, this, in turn, inhibits prostaglandin synthesis. These effects decrease the formation of inflammatory mediators.

Ketoprofen

Ketoprofen is used for relief of mild to moderate pain and inflammation. Small dosages are indicated initially in small patients, elderly patients, and patients with renal or liver disease. Doses higher than 75 mg do not increase the therapeutic effects. Administer high doses with caution, and closely observe the patient's response.

Flurbiprofen

Flurbiprofen may inhibit COX, thereby inhibiting prostaglandin biosynthesis. These effects may result in analgesic, antipyretic, and anti-inflammatory activities.

Analgesics

Class Summary

Pain control is essential to quality patient care. It ensures patient comfort, promotes pulmonary toilet, and aids physical therapy regimens. Many analgesics have sedating properties that benefit patients who experience moderate to severe pain.

Acetaminophen and codeine (Tylenol #3)

This combination is indicated for mild to moderate pain.

Acetaminophen (Tylenol, Aspirin-Free Anacin, Cetafen, Mapap Extra Strength)

Acetaminophen is the drug of choice for the treatment of pain in patients with documented hypersensitivity to aspirin or NSAIDs, as well as in those with upper GI disease or who are taking oral anticoagulants.

Hydrocodone bitartrate and acetaminophen (Vicodin ES, Lortab, Lorcet Plus, Norco, Maxidone)

This agent is indicated for the relief of moderately severe to severe pain.

Tramadol (Ultram, Ryzolt)

Tramadol is an analgesic that probably acts over monoaminergic and opioid mechanisms. Its monoaminergic effect is shared with tricyclic antidepressants. Tolerance and dependence appear to be uncommon.

 

Questions & Answers

Overview

What are abdominal hernias?

How are abdominal hernias detected?

What are the characteristics of asymptomatic abdominal hernias?

What are the characteristics of incarcerated abdominal hernias?

What are characteristics of strangulated abdominal hernias?

How are abdominal hernias identified?

What are characteristics of different types of abdominal hernias?

How are abdominal hernias diagnosed?

Which lab studies are used in the diagnosis of abdominal hernias?

Which imaging studies are used in the diagnosis of abdominal hernias?

What is the medical treatment for abdominal hernias?

What are the surgical treatment options for inguinal hernias?

What are the surgical treatment options for different types of abdominal hernias?

How common are abdominal hernias?

What is an abdominal hernia?

How is omphalocele differentiated from gastroschisis in congenital abdominal hernias?

What is the anatomy of the anterior abdominal wall in relation to abdominal hernias?

What is the anatomy of the paired rectus abdominis muscles in relation to abdominal hernias?

What are the anatomic features of the anterior and posterior laminae in relation to abdominal hernias?

What are the anatomic features of the external oblique muscles in relation to abdominal hernias?

What are the anatomic features of the transversus abdominis in relation to abdominal hernias?

What are the anatomic features of the caudad margin in relation to abdominal hernias?

What are the anatomic features of the innominate and transversalis fasciae in relation to abdominal hernias?

What are the anatomic features of the posterolateral (lumbar) region in relation to abdominal hernias?

What is the anatomy of the serratus posterior inferior in relation to abdominal hernias?

What is the anatomy of the latissimus dorsi in relation to abdominal hernias?

What are the anatomic features of the superior lumbar triangle of Grynfeltt-Lesshaft in relation to abdominal hernias?

What is the inferior lumbar triangle of Petit relative to abdominal hernias?

What is the anatomy of the blood vessels involved in abdominal hernias?

What is the anatomy of the inguinal ligament involved in abdominal hernias?

What is the anatomy of the transversus abdominis in abdominal hernias?

What is the anatomy of the pectineal ligament involved in abdominal hernias?

What is the anatomy of the aponeurotic band in relation to abdominal hernias?

What is the anatomy of the iliacus fascia in relation to abdominal hernias?

What is the anatomy of the femoral sheath in relation to abdominal hernias?

What is the anatomy of the borders of the Hesselbach triangle in relation to abdominal hernias?

What are the anatomic features of the transversalis fascia and transversus abdominis in abdominal hernias?

What is the anatomic role of male reproductive parts in abdominal hernias?

What is the anatomy of the inferior epigastric artery in relation to abdominal hernias?

What is the anatomy of the iliohypogastric and ilioinguinal nerves in relation to abdominal hernias?

What is the anatomy of the umbilical ligaments in relation to abdominal hernias?

What are the anatomic features of the internal inguinal ring involved in abdominal hernias?

What is the anatomy of the obturator internus in relation to abdominal hernias?

What is the anatomy of the obturator canal in relation to abdominal hernias?

What is the pathophysiology of abdominal inguinal hernias?

What is the role of stress in the development of abdominal inguinal hernias?

What are some conditions associated with an increased incidence of abdominal inguinal hernias?

How does acquired elastase deficiency lead to increased incidence of abdominal hernias?

What is a direct inguinal hernia?

What is an indirect inguinal hernia?

What is the pathophysiology of a femoral hernia?

What is the pathophysiology of an abdominal umbilical hernia?

Which conditions should be considered in children with abdominal umbilical hernias?

What is the pathophysiology of an abdominal Richter hernia?

What is the pathophysiology of an abdominal incisional hernia?

What is the pathophysiology of an abdominal spigelian hernia?

What are the types of abdominal spigelian hernias?

What is the pathophysiology of an abdominal obturator hernia in relation to abdominal hernias?

What causes different types of abdominal hernias?

What are the embryogenic factors in omphalocele and gastroschisis in congenital abdominal hernias?

What anomalies are associated with improper development of portions of the abdominal wall in abdominal hernias?

What are the clinical manifestations of maldevelopment of the interior (caudal) fold in abdominal hernias?

What are the clinical manifestations of maldevelopment of the lateral fold in abdominal hernias?

What is an omphalocele-exstrophy-imperforate anus-spinal defects (OEIS) complex in abdominal hernias?

What is the correlation between maternal smoking and abdominal hernias?

What is gastroschisis and how does it occur?

What causes an indirect inguinal abdominal hernia?

How does a congenital abdominal hernia develop during the first trimester?

How does a congenital abdominal hernia develop in a male fetus?

What is the embryonic difference in the development of the inguinal canal between males and females?

What is the embryonic development of gonads and how does the process contribute to the abdominal hernias?

What increases intra-abdominal pressure and may cause an abdominal hernia?

How common are abdominal hernias in the US?

What is the incidence of omphalocele and gastroschisis in the US?

How common are abdominal hernias in developing countries?

How is the prevalence of abdominal hernias affected by age?

What are the age-related demographics for abdominal inguinal hernias?

How common are abdominal umbilical hernias?

Which types of abdominal hernias are most common in older women?

What are the age-related demographics for incarcerated or strangulated abdominal hernias?

What are the sex-related demographics for abdominal inguinal hernias?

What are the sex-related demographics for abdominal sliding hernias?

What are the sex-related demographics for abdominal femoral hernias?

What are the sex-related demographics for abdominal epigastric and internal supravesical hernias?

What are the race-related demographics for abdominal umbilical hernias?

What are the prognostic factors in abdominal hernias?

What bowel complications are associated with abdominal hernias?

What is the mortality rate for abdominal inguinal hernias?

What are the surgical complications and recurrence rates for abdominal inguinal hernias?

What are potential complications of abdominal inguinal hernia repair?

What causes postoperative death in patients with abdominal inguinal hernias?

What postoperative complications are associated with abdominal inguinal hernia repair?

What is the recurrence rate for abdominal hernias?

What are the technical factors that increase the likelihood of recurrence of abdominal inguinal hernias?

What are the potential complications and recurrence rate for noninguinal abdominal hernias?

Which complications are associated with gastroschisis and omphalocele (abdominal hernias)?

What is the infant mortality rate for gastroschisis or omphalocele (abdominal hernias)?

How common is intestinal atresia in patients with gastroschisis (abdominal hernia)?

When is antireflux medication indicated for the treatment of gastroschisis and omphalocele (abdominal hernias)?

What is the long-term outcome of gastroschisis and omphalocele (abdominal hernias)?

What educational information should be provided to patients with abdominal hernias?

Presentation

What is the clinical presentation of an abdominal hernia?

What are the characteristics of an asymptomatic abdominal hernia?

What are the symptoms of an abdominal hernia?

What are the symptoms of an incarcerated abdominal hernia?

What are the symptoms of a strangulated abdominal hernia?

What is the significance of pain associated with an abdominal hernia?

Which symptoms are associated with different types of abdominal hernias?

How is a physical exam performed on a patient with suspected abdominal hernia?

How is an abdominal hernia identified?

What are the physical findings that distinguish direct and indirect abdominal hernias?

How are strangulated and incarcerated abdominal hernias differentiated?

How is a physical exam performed on an adult patient with an abdominal inguinal hernia?

How is a physical exam performed on a child with an abdominal inguinal hernia?

What are the physical findings in sliding inguinal abdominal hernias?

What are the physical findings that distinguish different types of abdominal hernias?

What are the physical findings associated with incarcerated abdominal hernias?

What are the physical findings of a hydrocele in an abdominal hernia?

When is treatment not indicated for a hydrocele?

What are the clinical findings of hydroceles in children with abdominal hernias?

What is an abdominoscrotal hydrocele?

What is the relationship between abdominal hernias and intestinal obstruction?

What are the clinical presentations of abdominal spigelian hernias?

When is a testicular tumor considered in the evaluation of an abdominal hernia?

What is the differential diagnosis of a groin mass inferior to the inguinal ligament and medial to the femoral vessels in the diagnosis of an abdominal hernia?

Which clinical findings suggest an incarcerated abdominal femoral hernia?

How is cat-scratch disease lymphadenitis differentiated from an abdominal inguinal hernia?

Which infections can cause inguinofemoral adenopathy which may be mistaken for an abdominal inguinal hernia?

How are the different types of abdominal femoral hernias differentiated?

What are the clinical characteristics of abdominal obturator hernias?

What is the clinical presentation of abdominal sciatic and perineal hernias?

What is the clinical presentation of abdominal umbilical hernias?

What is the relationship between diastasis recti and abdominal hernias?

What is the difference between umbilical granuloma and umbilical polyps in abdominal hernias?

How are abdominal wall defects in fetuses detected?

When are abdominal hernias identified in neonates?

DDX

Which conditions associated with abdominal hernias should be assessed in the history and physical exam?

What are the differential diagnoses for Abdominal Hernias?

Workup

Which diagnostic techniques are recommended in the workup of abdominal hernias?

Which provocative factors should be evaluated in the workup of abdominal hernias?

Which lab studies are used in the workup of abdominal hernias?

What is the role of plain radiographs in the diagnosis of abdominal hernias?

What is the role of nonionic contrast in the imaging workup of abdominal hernias?

Which imaging studies may be helpful in the diagnosis of incarcerated or strangulated abdominal hernias?

What is the role of CT scanning in the diagnosis of abdominal hernias?

What is the role of ultrasonography in the diagnosis of abdominal hernias?

What are the histologic findings in pediatric abdominal hernias?

Treatment

What is the purpose of binders or corsets in the treatment of abdominal hernias?

When should a surgeon be consulted for repair of an abdominal hernia?

What are the treatment approaches for abdominal inguinal hernias?

When is abdominal umbilical hernia repair indicated?

When should an abdominal umbilical hernia be repaired in young children?

What is the importance of the size of the fascial defect in the repair of abdominal umbilical hernias?

How common are incarcerated abdominal umbilical hernias?

Which types of abdominal hernias should be repaired due to the risk of incarceration?

What are the indications for elective and acute repair of abdominal hernias?

How is an abdominal hernia reduced?

How is an abdominal hernia reduction modified in young children and infants?

What treatment is indicated if reduction of an abdominal hernia is not successful?

What are the elements of the spontaneous reduction technique in the treatment of an abdominal hernia?

What is the role of silver nitrate in the treatment of umbilical granuloma associated with an abdominal hernia?

What risks are associated with topical treatments for omphalocele (abdominal hernia)?

How is progressive compression dressing used in the treatment of an omphalocele sac (abdominal hernia)?

When are topical medications and abdominal wrapping indicated in the treatment of an omphalocele (abdominal hernia)?

What are the options for delayed fascial closure in the treatment of an omphalocele (abdominal hernia)?

What are the fundamentals of indirect inguinal hernia repair?

When can patients who’ve had surgical repair of abdominal inguinal hernia return to work?

What are the Bassini and Shouldice repair techniques for the surgical treatment of abdominal inguinal hernias?

What is the Cooper repair for the surgical treatment of abdominal inguinal hernias?

How is mesh used in the repair of abdominal inguinal hernias?

How effective is the peritoneal approach for tension-free mesh repair of an abdominal inguinal hernia?

How is the preperitoneal approach performed in the surgical repair of abdominal inguinal hernias?

How are simple inguinal hernias repaired in children?

How is the fascia repaired in simple inguinal abdominal hernia repair in children?

How is intersex differentiation syndrome investigated in girls with abdominal inguinal hernias?

What is the most common cause of intersex differentiation syndrome in girls with abdominal inguinal hernias?

What are the characteristics of an incarcerated ovary in an abdominal inguinal hernia?

When is immediate surgical repair indicated in pediatric abdominal inguinal hernia?

How is the surgical procedure performed for the treatment of abdominal inguinal hernias in children?

What are the laparoscopic techniques used in the surgical treatment of abdominal inguinal hernias?

What are the benefits and drawbacks of laparoscopic procedures for the surgical treatment of abdominal inguinal hernias?

What information should be provided to adult patients prior to surgical treatment abdominal inguinal hernias?

What is the purpose of prosthetic material in the surgical treatment of adults with abdominal inguinal hernias?

What are the treatment approaches for adults with very large chronic abdominal inguinal hernias?

Is preoperative antibiotic prophylaxis indicated in adults with abdominal inguinal hernias?

What is the role of neurectomy in adults with abdominal inguinal hernias?

What are the treatment approaches for neonates with abdominal inguinal hernias?

What are the treatment approaches for premature infants with abdominal inguinal hernias?

What are the treatment approaches for children with bilateral abdominal inguinal hernias?

What is the role of peritoneoscopy in the surgical treatment of abdominal inguinal hernias in children?

Which providers should not perform surgical repair of abdominal inguinal hernias in children?

Are perioperative antibiotics indicated in the surgical treatment of abdominal inguinal hernias in children?

Is abdominal inguinal hernia repair an outpatient procedure in premature infants and neonates?

What is the surgical treatment for an abdominal sliding hernia?

What is the treatment for atypical tuberculous adenitis in patients with abdominal hernias?

How are abdominal umbilical hernias repaired in children?

What is the role of cosmesis in the surgical repair of abdominal umbilical hernias in children?

How is an abdominal epigastric hernia surgically repaired?

How is an abdominal spigelian hernia surgically repaired?

How is an abdominal interparietal hernia surgically repaired?

How is an abdominal supravesical hernia surgically repaired?

What is the surgical approach in the repair of an abdominal lumbar hernia?

What is the surgical approach in the repair of an abdominal obturator hernia?

When is the transperitoneal approach indicated in the surgical repair of an abdominal sciatic hernia?

When is the transgluteal approach indicated in the surgical repair of an abdominal sciatic hernia?

Which surgical approach is preferred in the repair of an abdominal perineal hernia?

Why have the outcomes of abdominal hernia repair in children improved over the years?

Why has there been modest progress in mortality rates in patients with syndromic omphaloceles?

What are the considerations in the delivery and early perioperative care of neonates with abdominal wall defects?

What are the major challenges in the treatment of gastroschisis and omphaloceles?

What is the best treatment approach for omphalocele and gastroschisis?

What is the nonoperative management strategy for gastroschisis?

Why are intra-abdominal pressure measurements important in neonates with abdominal wall hernias?

What is the role of abdominal binding in the treatment of omphaloceles?

How is intestinal atresia managed in the treatment of abdominal wall hernias?

When should Beckwith-Wiedemann syndrome be suspected in neonates with abdominal hernias?

How are malformations of abdominal folds characterized in the treatment of abdominal hernias?

How are umbilical remnants managed in in the treatment of abdominal hernias in neonates?

What is involved in the long-term monitoring of abdominal hernias?

Medications

When are antibiotics indicated in the treatment of abdominal hernias?

Which medications in the drug class Analgesics are used in the treatment of Abdominal Hernias?

Which medications in the drug class Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) are used in the treatment of Abdominal Hernias?

Which medications in the drug class Antianxiety Agents are used in the treatment of Abdominal Hernias?

Which medications in the drug class General Anesthetics are used in the treatment of Abdominal Hernias?

Which medications in the drug class Local Anesthetics are used in the treatment of Abdominal Hernias?

Which medications in the drug class Antibiotics are used in the treatment of Abdominal Hernias?