Disorders of the Umbilicus

During development, the embryonic disk is in contact with the yolk sac anteriorly (see the image below). As the embryo grows and differential growth of tissues leads to the folding appearance of the embryo, the ventral attachment of the yolk sac narrows. The intracoelomic portion of the yolk sac becomes the primitive alimentary canal and attaches to the extracoelomic portion through the vitelline duct. The allantois buds from the hindgut and grows into the body stalk. The yolk stalk and the body stalk eventually fuse to become the umbilical cord.

Cartoon illustrating the developing umbilical cord. (A) Embryonic disk: At this stage, the ventral surface of the fetus is in contact with the yolk sac. (B) The yolk sac narrows as the fetus grows and folds. The intracoelomic yolk sac forms the intestine and communicates with the extracoelomic yolk sac through the vitelline duct. The vitelline duct is also referred to as the omphalomesenteric duct and the yolk stalk. The allantois has begun to grow into the body stalk. (C) The yolk and body stalks fuse to become the umbilical cord.

As the abdominal wall forms, the umbilical ring is narrowed. The vitelline and umbilical vessels, vitelline duct, and allantois should be absent in the umbilicus at term. Residual tissue leads to remnants that require surgical intervention. During exploration for a sinus or fistula, all structures, including the round ligament, median, and medial umbilical ligaments, must be identified (see the images below). An omphalomesenteric or urachal sinus or fistula must be dissected back to its origin in the ileum or bladder, respectively.

Umbilical region viewed from the posterior surface of the abdominal wall of an infant with the umbilical cord attached. UA: Umbilical artery; UV: Umbilical vein; RL: Round ligament (obliterated umbilical vein); UR: Umbilical ring; UL: Umbilical ligament; medial (obliterated umbilical arteries); median (obliterated urachus). Note fascial covering of surface and umbilical ring.

Anatomic relationship between the umbilicus and its embryologic attachments.

Failure of the normal obliterative processes of the vitelline duct and the urachus leads to abnormal communications or cysts. Retention of components of the umbilical cord can also produce a mass or drainage.

A patent umbilical ring at birth is responsible for most umbilical hernias. The umbilical opening is usually inferiorly reinforced by the attachments of the median umbilical ligament (the obliterated urachus) and the paired medial umbilical ligaments (the obliterated umbilical arteries) and is more weakly superiorly reinforced by the round ligament (the obliterated umbilical vein). (See the image below.)

Umbilical region viewed from the posterior surface of the abdominal wall of an infant with the umbilical cord attached. UA: Umbilical artery; UV: Umbilical vein; RL: Round ligament (obliterated umbilical vein); UR: Umbilical ring; UL: Umbilical ligament; medial (obliterated umbilical arteries); median (obliterated urachus). Note fascial covering of surface and umbilical ring.

Richet fascia, derived from the transversalis fascia, covers the ring. The peritoneum covers the innermost portion of the ring. Variability in the attachment of the ligaments and the covering by Richet fascia may predispose some children to developing umbilical hernias (see the image below). Variations in the covering of the umbilical ring by umbilical fascia include the following:

• Umbilical fascia completely covers the ring (36%)
• Umbilical fascia is present but does not cover the ring (4%), or fascia is absent (16%)
• Umbilical fascia covers only the superior portion of the ring (38%)
• Umbilical fascia covers only the inferior portion of the ring (6%)

Variations in the umbilical ring structure. (A) Usual configuration of the round ligament and urachus. (B) Less common configuration that can result in weakness at the umbilical ring.

Nevertheless, many children undergo spontaneous closure in the first few years of life. The pressure exerted on the umbilical skin, even when only a small umbilical defect is present, can result in marked stretching of the skin and a proboscis appearance.

The development of the anterior abdominal wall depends on differential growth of embryonic tissues (see the image below). As the embryo grows, the yolk sac is divided into an intracoelomic portion and an extracoelomic portion. The intracoelomic portion becomes the primitive alimentary canal and communicates with the extracoelomic portion through the vitelline duct, also known as the omphalomesenteric duct. This communication is lost at 5-7 weeks' gestation. Persistence of part or all of this connection results in omphalomesenteric anomalies.

Cartoon illustrating the developing umbilical cord. (A) Embryonic disk: At this stage, the ventral surface of the fetus is in contact with the yolk sac. (B) The yolk sac narrows as the fetus grows and folds. The intracoelomic yolk sac forms the intestine and communicates with the extracoelomic yolk sac through the vitelline duct. The vitelline duct is also referred to as the omphalomesenteric duct and the yolk stalk. The allantois has begun to grow into the body stalk. (C) The yolk and body stalks fuse to become the umbilical cord.

In the third week, the yolk sac develops a diverticulum, the allantois, which grows into the body stalk. As the distal hindgut and the urogenital sinus separate, the developing bladder remains connected to the allantois through a connection called the urachus.[5] Persistence of the urachus leads to urachal remnants. Subsequently, the yolk and body stalks fuse to become the umbilical cord. Development of the abdominal wall narrows the umbilical ring, which should close before birth. Persistence of the ring results in an umbilical hernia.

The frequencies of the many different umbilical disorders vary. Umbilical infections are now identified in fewer than 1% of hospitalized newborns.

Umbilical hernias are commonly identified in early infancy; however, most spontaneously close. No sex predilection is noted. The incidence at age 1 year ranges from 2-15%. Incidence is increased in infants who are black and in infants with low birth weight, Down syndrome, trisomy 13, trisomy 18, or Beckwith-Wiedemann syndrome.

The outcome for infants and children with umbilical hernias and embryologic remnants is generally excellent. In most cases, no long-term problems occur. However, Rosen et al suggested that umbilical hernia repair may increase the incidence of functional gastrointestinal disorders in childhood.[6]

In contrast, in most series, omphalitis leading to necrotizing fasciitis is associated with a high mortality, possibly as high as 80%. Necrotizing fasciitis can also lead to portal venous thrombosis and portal hypertension.

Umbilical infections can occur because of an embryologic remnant or poor hygiene. Traditionally, gram-positive organisms, such as Staphylococcus aureus and Streptococcus pyogenes, were most commonly identified. Gram-negative and polymicrobial infections are seen today, especially in rapidly progressing cellulitis and necrotizing fasciitis.

Umbilical granulomas appear as 1-mm to 1-cm, pink, friable lesions at the base of the umbilicus. They produce variable amounts of drainage that can irritate the surrounding skin. An umbilical polyp is brighter red than a granuloma and represents retained intestinal or gastric mucosa from the vitelline duct.

The presentation of omphalomesenteric remnants depends on the specific type of defect (see the first image below). If a communication persists from the terminal ileum to the umbilicus, intestinal contents or stool can be observed leaking from the umbilicus. Prolapse of intestine through an omphalomesenteric fistula can also be observed (see the second image below). The drainage from a fistula that does not communicate with the ileum varies; it may be clear, bloody, or purulent. Cystic remnants may become infected and manifest with pain and swelling.

Omphalomesenteric duct remnants. (A) Meckel diverticulum. Note feeding vessel. (B) Meckel diverticulum attached to posterior surface of anterior abdominal wall by a fibrous cord. (C) Fibrous cord attaching ileum to abdominal wall. (D) Intestinal-umbilical fistula. Intestinal mucosa extends to skin surface. (E) Omphalomesenteric cyst arising in a fibrous cord. The cyst may contain intestinal or gastric mucosa. (F) Umbilical sinus ending in a fibrous cord attaching to the ileum. (G, H) Omphalomesenteric cyst and sinus without intestinal attachments.

Photograph of newborn with intestinal prolapse through a patent omphalomesenteric duct. Both the proximal and distal limbs of the intestine have prolapsed. The umbilicus was explored, the bowel was easily reduced, and the patent duct was excised. The child was discharged from the hospital 2 days later.

The presentation of urachal remnants also varies. Clear drainage from the umbilicus is characteristic of a urachal fistula. Drainage of urine from the umbilicus may suggest bladder outlet obstruction and warrants further investigation.

A urachal cyst is usually discovered as a painful mass between the umbilicus and suprapubic area when it becomes infected. Pain and retraction of the umbilicus during urination may suggest a urachal anomaly. A urachal sinus manifests with drainage that can be clear or purulent and occurs through the umbilicus or midline skin below the umbilicus (see the image below).

Urachal sinus with purulent drainage in midline below the umbilicus (black arrow). A laparoscope was placed in the supraumbilical crease (red arrow) for mobilization of the internal portion of the urachal remnant as depicted in the next image.

Patients with umbilical hernias present early in life with bulging at the umbilicus. The swelling is most prominent when the infant or child is crying or straining. Umbilical hernias are usually asymptomatic and rarely cause pain. The skin can become severely stretched, which may be alarming to parents and physicians (see the image below). Parents often mention that the child plays with the redundant skin.

Preoperative photograph demonstrating umbilical hernia with redundant skin.

Incarceration, strangulation, bowel obstruction, erosion of the overlying skin, and bowel perforation are rare events in infants and small children. The risk of incarceration increases significantly in adults with umbilical hernias.

Patients with umbilical infections can present with drainage from the umbilicus, swelling, and redness. Cellulitis may rapidly progress and lead to necrotizing fasciitis. Necrotizing fasciitis is characterized by abdominal distention, tachycardia, purpura, leukocytosis, and other signs of sepsis despite antibiotic therapy.

For healthy children undergoing umbilical hernia repair or excision of omphalomesenteric or urachal remnants, routine laboratory tests are not needed. However, for infants with necrotizing fasciitis, who may be extremely ill, umbilical cultures and blood cultures are needed. Frequent hematologic, electrolyte, and blood gas analyses may be necessary.

Radiography is not indicated in most children with umbilical disorders. Umbilical hernias are diagnosed by means of physical examination.

Fistulography or sinography may be performed if a definitive opening is observed within the umbilicus. Fistulography can be performed by injecting water-soluble contrast medium into the opening at the base of the umbilicus. If the track is blind-ended, the child has a sinus; if it enters the intestine or bladder, a fistula is present.

Ultrasonography is helpful when a mass is present. It may be useful in identifying cysts of the umbilicus. Evaluating for a urachal cyst is useful; this cyst most commonly appears as a mass between the umbilicus and suprapubic area. Ultrasonography can also be used to identify a patent urachal fistula between the umbilicus and bladder.

Plain radiography may be useful in children with omphalitis. Air in the subcutaneous tissue or muscle planes is an ominous sign. An umbilical hernia may be incidentally observed on an upper gastrointestinal tract contrast study with small-bowel follow-through (see the image below).

Upper gastrointestinal contrast study showing incidental umbilical hernia in an infant. Red line outlines the umbilical hernia. The arrow shows contrast flowing into the intestine within the umbilical hernia. The umbilical hernia was easily reducible and no intervention based on this study was performed.

Cystography or cystoscopy may be indicated to identify bladder outlet obstruction in children draining frank urine from a urachal fistula. However, studies suggest that, in most cases, history and ultrasonography are sufficient for the diagnosis.[7]

The histology of umbilical remnants depends on the tissue of origin and may reveal intestinal or gastric mucosa. Examination of urachal remnants shows transitional or columnar epithelium.

Small umbilical granulomas usually respond to silver nitrate application. Large umbilical granulomas or those that persist after silver nitrate treatment require surgical excision.

Omphalomesenteric remnants and urachal remnants require surgical excision. The precise diagnosis is often not confirmed until surgery is performed and the anatomy of the umbilicus is established.

The diameter of the umbilical ring defect is predictive of spontaneous closure. The length of the protruding skin is not prognostically significant. Umbilical hernias with ring diameters less than 1 cm are more likely to spontaneously close than those with ring diameters more than 1.5 cm. Surgery is indicated for all symptomatic umbilical hernias. Incarceration, strangulation, skin erosion, and bowel perforation are indications for immediate surgery. Similarly, patients presenting with pain should be repaired on an elective basis.

Asymptomatic umbilical hernias can be safely monitored until the child is aged 4-5 years to allow spontaneous closure, especially if the ring defect is small. Because umbilical hernias with larger defects (ie, >1.5 cm) are unlikely to close spontaneously, surgery can be performed at an earlier age.

Similarly, closing umbilical hernias with large ring defects is reasonable in younger children if the child is having a general anesthetic for another procedure, such as an inguinal hernia repair. It is also reasonable to consider surgery in younger children who have a large protrusion of the umbilical skin that is causing distress to the parents.

For necrotizing fasciitis and gangrene of the umbilical skin, emergency surgical debridement is required and can be life-saving.

No specific contraindications to surgery for umbilical disorders are known, and timing of surgery depends on the general medical condition of the infant or child.

There remains some controversy regarding the optimal timing for umbilical hernia repair, and the true instance of complications related to umbilical hernias in adults is not known.

Most surgeons agree that in the majority of cases, small hernias can be monitored safely. Although spontaneous closure does occur, large hernias with large fascial defects are less likely to close on their own, and continued stretching of the umbilical skin may make closure more difficult. Therefore, many surgeons advocate earlier repair in these children. Others argue that umbilical hernias should be monitored until children reach the age of 5 years.

The umbilicus is a common site for port entry for laparoscopic surgery and is being used for single-incision laparoscopic surgery.

Medical therapy is indicated only when infection is present. For omphalitis or necrotizing fasciitis, broad-spectrum antibiotics are needed. Antibiotics are also administered for acute infection of omphalomesenteric and urachal remnants. Surgical drainage is often needed.

Many umbilical hernias spontaneously close; currently, no medical therapy to hasten this process is recognized.

Silver nitrate application to umbilical granulomas is usually successful. One or more applications may be needed. Care must be taken to avoid contact with the skin. Silver nitrate can cause painful burns. Small umbilical granulomas with a narrow base may be safely excised in the office setting. Large granulomas and those growing in response to an umbilical fistula or sinus do not resolve with silver nitrate and must be surgically excised in the operating room setting.

Surgical therapy is the mainstay of treatment for the following umbilical conditions: 

• Large persistent umbilical granulomas
• Umbilical polyps
• Omphalomesenteric remnants
• Urachal remnants
• Umbilical gangrene and necrotizing fasciitis
• Umbilical hernias that are symptomatic or do not spontaneously close

Often, surgery on the umbilicus is performed for a mass or drainage without a specific preoperative diagnosis. Surgical principles include identification of all structures of the umbilicus, excision of urachal or omphalomesenteric remnants, closure of the umbilical ring, and preservation of the natural appearance of the umbilicus.

Laparoscopy is a valuable adjunct to open umbilical exploration. It allows identification of both normal and abnormal structures. The laparoscopic approach can be used to remove urachal remnants, as well as omphalomesenteric abnormalities (see the images below).

Laparoscopic view of urachal fistula, which extends from umbilicus above to bladder below. Image courtesy of Eugene S Kim, MD.

Laparoscopic view of remnant fibrous band of omphalomesenteric duct, which extends from umbilicus to terminal ileum below. Image courtesy of Eugene S Kim, MD.

If acute infection with an abscess is present, surgical drainage is carried out in the operating room or by means of interventional radiology. In most cases, definitive surgical resection of the underlying lesion is needed several weeks following the initial infection.

Wide surgical debridement of the umbilicus and abdominal wall can be life-saving in patients with necrotizing umbilical infections.

Operative details

Most umbilical procedures can be performed on an elective basis, and surgery should be scheduled when the child is in his or her usual state of health. The exceptions are infants with necrotizing infections and those with stool draining from the umbilicus, indicative of an enteric-umbilical fistula.

Mechanical bowel preparation is not needed. Perioperative antibiotics are used for sinuses and fistulas. Antibiotics are not needed for umbilical hernia repairs.

General anesthesia is used. The child is placed supine. The abdomen should be widely prepared with antiseptic solution and draped in standard fashion. Omphalomesenteric and urachal remnants can be approached directly through the umbilicus or through an incision in the infraumbilical or supraumbilical crease. Larger children may need additional or larger incisions. Laparoscopy can be performed through the umbilical incision.

During exploration of the umbilicus, an attempt is made to identify all anatomic structures (see the image below). A history of infection and resultant inflammation or scar tissue can complicate identification of normal and abnormal structures. Dissection of the umbilicus off the fascia is often useful and can provide access for a small port to perform laparoscopy. The umbilical vein (round ligament), the umbilical arteries (medial umbilical ligaments), and the urachus (median umbilical ligament) can often be identified.

Umbilical region viewed from the posterior surface of the abdominal wall of an infant with the umbilical cord attached. UA: Umbilical artery; UV: Umbilical vein; RL: Round ligament (obliterated umbilical vein); UR: Umbilical ring; UL: Umbilical ligament; medial (obliterated umbilical arteries); median (obliterated urachus). Note fascial covering of surface and umbilical ring.

Anatomic relationship between the umbilicus and its embryologic attachments.

A patent vitelline duct must be traced to its origin and divided. If a Meckel diverticulum is present (see the image below), it is excised. Similarly, the urachus should be traced to its origin and divided. Broad-based connections of the urachus and bladder are closed in two layers.

Omphalomesenteric duct remnants. (A) Meckel diverticulum. Note feeding vessel. (B) Meckel diverticulum attached to posterior surface of anterior abdominal wall by a fibrous cord. (C) Fibrous cord attaching ileum to abdominal wall. (D) Intestinal-umbilical fistula. Intestinal mucosa extends to skin surface. (E) Omphalomesenteric cyst arising in a fibrous cord. The cyst may contain intestinal or gastric mucosa. (F) Umbilical sinus ending in a fibrous cord attaching to the ileum. (G, H) Omphalomesenteric cyst and sinus without intestinal attachments.

Laparoscopy is a useful adjunct, especially when there is a confirmed preoperative diagnosis or when no anomaly is found during the exploration (see the images below).[8] Additional ports can be placed to remove identified urachal or omphalomesenteric structures. Removed structures are sent to pathology for histologic examination.

Laparoscopic removal of urachal cyst (U). L indicates the left medial umbilical ligament. R indicates the right medial umbilical remnant. B indicates the bladder. The distal attachment to the bladder is being grasped.

Laparoscopic removal of urachal cyst. View is from left lower abdomen port. The umbilicus is on the right and the bladder on the left. The attachments or the urachal cyst to the bladder and the umbilicus have been clipped (not shown) and divided. Note the convergence of the right and left medial umbilical ligaments as they approach the umbilical ring on the right.

Photograph of laparoscopically removed urachal cyst and its attachments.

The umbilical fascia is closed with interrupted or running suture. The umbilical skin is then closed. Attempts should be made to create a natural-appearing umbilicus. Antibiotic ointment and a light dressing can be applied to the incision. If an abscess is identified preoperatively or found intraoperatively, an incision-and-drainage procedure is indicated. Definitive resection should be delayed.

Umbilical hernias are approached through an incision in the infraumbilical or supraumbilical crease. Dissection is carried down to the level of the fascia. The hernia sac is identified at its base and encircled. Contents from the hernia sac should be reduced. The sac is then disconnected from its attachment with the umbilicus.

Care is taken to avoid injury to contents within the hernia sac and to the umbilical skin. Opening the anterior surface of the sac may help to avoid injury to the bowel. The sac is resected down to the level of the fascia. The umbilical fascia is closed with interrupted or running absorbable suture. For large or recurrent hernias, nonabsorbable suture is used by many surgeons. The wound should be inspected and meticulous hemostasis achieved.

The umbilicus is tacked down to the fascia with an interrupted suture. The subcutaneous tissue is reapproximated with a few interrupted sutures, and the skin is closed with a subcuticular stitch. Bupivacaine can be injected for postoperative analgesia. The skin is cleaned, and Steri-Strips are applied. A pressure dressing may be used for large hernias to prevent a postoperative hematoma or seroma.

Routine umbilicoplasty (see the image below), the removal of excessive umbilical skin, is generally not needed. In most cases, a redundant umbilicus appears more natural than a neoumbilicus. Several techniques can be used for extremely protuberant umbilical hernias. A simple technique is to invert the umbilicus over a finger so that the undersurface is exposed. The skin is then incised circumferentially so that a 1-cm to 2-cm rim of umbilicus remains. The umbilical skin defect is reapproximated from within the umbilicus and tacked down to the fascia.

Neoumbilicus following umbilicoplasty.

For necrotizing fasciitis, wide surgical debridement of the umbilicus and preperitoneal structures, skin, fat, muscle, and fascia back to healthy bleeding tissue is required.[9] A silo or fascial patch may be needed.

Most umbilical hernia repairs and excision of umbilical remnants can be performed as outpatient procedures. For incisions within the umbilicus not covered by adhesive bandages (eg, Steri-Strips), antibiotic ointment should be applied twice a day for 3-4 days. Pressure dressings may be removed in 24-48 hours.

Feedings can be initiated when the child recovers from the anesthetic. Incisions are generally kept dry for 3 days. No activity restrictions are indicated for infants and small children. Older children should avoid heavy activity for 1 week.

Most children need only acetaminophen for pain relief, especially when bupivacaine has been used. Older children may require narcotic analgesia.

Complications of any surgical procedure include intraoperative or postoperative bleeding. Bleeding problems are rare during umbilical surgery. A postoperative hematoma may occur when a large cavity is left after umbilical hernia repair.

Infection of the incision is also rare; however, if infection is present, treatment with antibiotics is indicated. Opening of the incision to drain an abscess may also be needed. Drainage following umbilical exploration and excision may indicate infection or retained embryologic tissue.

Recurrent umbilical hernias are very rare. Small children with larger umbilical hernias often have more pain and can develop a postoperative ileus. Silver nitrate can cause painful burns to the umbilical skin.

Children undergoing umbilical surgery must be seen in the surgery clinic 2-6 weeks after the surgical procedure, or sooner if problems occur.