Everything You Need To Know About Umbilical Hernias In Children

Umbilical hernias are commonly encountered congenital anomalies. Most of the time, they present as a protrusion of the umbilicus in the abdomen that is clearly visible and easily palpable. Because of how common they are, it is important to understand how they develop and what the treatment options are.

Definition

An umbilical hernia is medically defined as the protrusion of abdominal contents through a defect in the umbilicus. In children, umbilical hernias are congenital, and occur as a result of incomplete degeneration of the “vitelline duct”. Umbilical hernias are more common in children of Afro-American descent, although they are seen widely in all children. They are also more likely to occur in premature children. Female kids are at higher risk than their male counterparts.

Anatomy of a Hernia

Before we dig into the topic of umbilical hernias per se, let us first of all understand the anatomy of a hernia.

By definition, a hernia is made of 3 essential components: a hernia sac, a neck, a body and a hernia ring.

The hernia sac is the structure within which all the contents of the hernia are stored. The hernia neck is the space between the hernia ring and the hernia body. The hernia ring is the opening of the hernia sac; a patent opening through which the contents of the sac protrude outside. Finally, the body is simply the contents of the sac.

See Also: Hiatal hernia

How Does An Umbilical Hernia Develop?

At about week 4 of development, the fetus needs a connection with the extra-embryonic tissue to ensure nutrition and continuous growth. This is particularly necessary because at that stage, the umbilical cord is not yet fully formed and is still developing. Henceforth, the yolk sac, which is – at that stage - the primary source of nutrition for the fetus at earlier stages, narrows and forms a longitudinal tube that connects the embryological midgut to the developing umbilical cord. That tube is called the vitelline duct (or omphalomesenteric duct). The primary function of the vitelline duct is to provide adequate nutrients to the developing embryo until the umbilical cord and the placenta both become functional. When the umbilical cord has completely formed and has become fully functional, the vitelline duct degenerates through a physiological process called apoptosis (programmed cell death). At that stage, the umbilical cord takes over the nutrition purposes and connects the fetus to the maternal uterus via the placenta.

If apoptosis fails to occur, the vitelline duct persists and causes a so-called “vitelline fistula”. If apoptosis occurs only at the proximal end of the vitelline duct (the end attached to the midgut of the embryo), the distal end of the vitelline duct persists and causes weakness of the umbilical ring; resulting in a possible umbilical hernia. However, if the vitelline duct degenerates only at the distal end, the proximal end (attached to the midgut) persists and forms what we call a Meckel’s diverticulum.

How To Recognize An Umbilical Hernia?

In most cases, umbilical hernias present as a protrusion of the navel ring (umbilicus). Upon palpating the child’s navel, it feels soft and empty (although it might not be). If you push through the navel, sometimes the contents of the hernia can return back into the abdomen. If that occurs, the hernia is said to be “reducible”.

For such children, the first symptoms are generally irritability associated with pain around the belly button. This indicates that the umbilical ring is very small and the abdominal contents are pushing through in order to make their way through the ring.

Dealing with an Umbilical hernia

Most people live a happy life and grow old with an umbilical hernia. In those cases, the defect does not impair the quality of life and does not cause any symptoms. However, some parents might choose to opt for surgical repair either for cosmetic reasons, or because the hernia is causing a lot of pain.

Another indication for surgical correction would be the presence of signs and symptoms of strangulation, which include:

- Pain around the navel accompanied by vomiting: sometimes, the child could also present with food aversion because of the pain and the vomiting.

- Skin discoloration (due to obstruction of blood flow to the area resulting in necrosis of surrounding tissue)

- Skin irritability and

- Fever (secondary to concomitant infection)

The choice of proceeding with surgical repair also depends on the age of the child. For children younger than 2 years of age and who present with no symptoms, it is generally advisable to delay surgery until the child is at least 4 years old (at which time his/her body is surely better able to handle stress related to surgery). However, if the child is younger than 4 years and presents with signs and symptoms of strangulation, surgery is not an option anymore, but rather, an emergency.

Surgery might also be recommended sooner if the hernia is large, causing discomfort, or there's a concern about the possibility of complications. It's rare, but an umbilical hernia can lead to complications, such as incarceration or already mentioned strangulation.

Incarceration​ is a complication when a portion of the intestine becomes trapped in the hernial sac and cannot be easily pushed back in. It can lead to bowel obstruction.

The surgery, called herniorrhaphy, is relatively straightforward. It involves making a small incision near the umbilicus, pushing the protruding tissue back into the abdomen, and then stitching the muscle closed.

Post-operative care typically involves keeping the area clean and watching for any signs of infection.

See Also: Hernia Operation: Recovery After Hernia Surgery

Other Related Conditions

Paraumbilical hernias

Paraumbilical hernias are similar to umbilical hernias. However, in paraumbuilical hernias, the protrusion of abdominal content occurs not through the umbilical ring, but through a weakness in the linea alba , 2cm below or above the umbilicus. The linea alba is simply the white midline of connective tissue that passes through the middle of the abdomen. Paraumbilical hernias are more common in adults, whereas umbilical hernias are most commonly observed in children.

Omphalocele and Gastroschisis

These are two isolated ventral body wall defects that result from two distinctive processes: the first one is the failure of the intestines to return to the abdomen after rotation, and the second one is the failure of the abdominal wall to completely fuse during development. These defects are diagnosed via ultrasound during the intrauterine life; and should be surgically corrected in the first few hours after birth.