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Disorders of the Umbilicus 355

umbilical hernia may continue to stretch and result in a proboscoid
umbilical hernia. In Africa, most parents are very accepting of its
appearance, in contrast to parents from developed countries. Once the
umbilical defect has spontaneously closed, the nipple-like umbilical
skin may continue to flatten, even during adolescence.
Aetiology
An umbilical hernia results when the umbilical ring fails to close.
Umbilical hernias are more frequent in premature, low birth weight,
and black infants. They also occur more often in children with ventricu-
loperitoneal shunts, ascites, obesity, and certain syndromes, including
Beckwith-Wiedemann, Trisomy 21, and Marfan’s syndromes.
Demographics
Umbilical hernias are common in Africa. In one study from Nigeria,
umbilical hernias were found in 91% of under-6-year-olds; 64% of 6- to
15
9-year-olds, and 46% of 10- to 15-year-olds. Meier found umbilical
hernias with a fascial defect >1 cm in 23% of Nigerian children younger
16
than 18 years old. Surprisingly, when 6- to 9-year-old Nigerian
children of high socioeconomic class were evaluated for an umbilical
17
hernia, only 1.3% of 7,968 children had an umbilical hernia. It is pos-
sible that nutrition may be a factor. Jelliffe found a higher incidence of Figure 57.6: Giant ulcerated umbilical hernia.
umbilical hernias in malnourished versus well-nourished adults (27%
versus 14%). 15 umbilicus, and pain. On examination, a child with an umbilical hernia
Complications usually presents with a protrusion of the umbilicus with contents that
are easily reducible. After reduction, the size of the fascial ring can
Complications, including incarceration, strangulation, and rupture of
be palpated; it can range from a few millimeters to more than 4 cm in
umbilical hernias, may occur. In developed countries, the incidence of
diameter. No other investigations are required for diagnosis.
incarceration or strangulation is rare—one paper reported an incidence
18
of 1 in 1,500 umbilical hernias. Rupture of umbilical hernias with Umbilical hernia repair is one of the most frequent procedures
1
performed by paediatric surgeons in developed countries. In Africa,
evisceration is even more rare, but has been reported in infants younger
than 6 months of age. 19,20 however, umbilical hernia repairs are more infrequent because the
hernias are usually repaired only if symptomatic or complicated.
Even though the incidence of incarceration and strangulation in
Generally accepted indications for management in Africa compared to
children with umbilical hernias in Africa is not known, it appears
the West are highlighted next.
to be higher than in the West (although this may in part reflect the
Due to the high rate of spontaneous closure and the fact that the
significantly higher prevalence of umbilical hernias in black children).
appearance of a proboscoid umbilical hernia is well tolerated by parents
For instance, at A. Le Dantec Hospital in Senegal, over a five-year
in Africa, conservative management of asymptomatic, easily reducible
period, 41 children had emergency operations for incarcerated or
21
strangulated umbilical hernias. At Jos University Teaching Hospital in umbilical hernias is recommended. In the West, conservative treatment
is generally recommended for small asymptomatic umbilical hernias
Nigeria, over an eight-year period, 23 children underwent surgery for
acute or recurrent incarceration. 16,19,22–24 (<2 cm fascial defect) in children younger than 4–5 years of age.
In Africa, surgical repair is reserved for symptomatic umbilical
In contrast, Okada et al. reviewed the literature from 1957 to 1999
25
and found a total of only 38 cases reported in children worldwide. hernias. Rarely, parents may request to have a proboscoid hernia
repaired. (For further discussion, see the “Ethical Issues” section in
In King’s College Hospital in London, only 3 incarcerated umbilical
this chapter.) In the West, surgical repair is generally recommended for
hernias were treated in children over a 20-year period (and all 3 of
26
these occurred in black children). The fact that most umbilical hernias hernias with large fascial defects (>1.5 cm), hernias that have failed to
spontaneously close by 4 to 5 years of age, and umbilical hernias with
in the West are repaired by 4–5 years of age does not account for the
significant proboscoid components.
apparent difference in the frequency of incarceration between the West
A classic Mayo “vest-over-pants” procedure or simple approximation
and Africa. In both Senegal and Nigeria, most of the incarcerations
with long-lasting absorbable suture are both acceptable for conventional
reported occurred in patients younger than 5 years of age; in Senegal,
umbilical hernia repairs. For complicated umbilical hernia repairs, the
the average age at incarceration was 14 months (range, 8 months–10
use of mesh may be considered in the closure of a very large uninfected
years); in Nigeria, the median was 4 years (range, 3 weeks–12 years).
umbilical hernia to prevent excess tension on the fascia. The use of mesh
Most incarcerated hernias do not have an inciting factor; however,
also prevents the development of an abdominal compartment syndrome,
bezoars, digested vegetable matter, parasitic worms, or ascites have
been implicated. 21,22,25 which could result with significant fascial tension. Surgical complications
are rare after umbilical hernia repairs. The outcome is excellent and
Umbilical hernias can incarcerate regardless of the size of the fascial
the mortality approaches zero for elective repairs. Rare postoperative
defect (Figure 57.6). In one report, a majority (52%) of the patients
eviscerations can be prevented by meticulous surgical technique.
with incarcerated hernias had medium-sized (0.5–1.5 cm) fascial
defects, whereas 24% occurred in small defects (<0.5 cm), and 24% Other Umbilical Problems
25
in large defects (>1.5 cm). Of the incarcerated hernias in which a Absent umbilicus
measurement was documented in one study in Nigeria, all had defects Malposition or absence of the umbilicus is encountered frequently
greater than 1.5 cm in diameter (not all, however, were measured). 22
in patients with bladder exstrophy. When the umbilicus is absent, an
Management omphaloplasty may be performed, as many ethnic groups are culturally
Factors that lead parents to seek medical care for their child in Africa sensitive to the absence of the navel. Research has been performed to
include the age of the child, size of the defect, height of protruding help the reconstructive surgeon locate the umbilicus in an aesthetically
pleasing location. 27