‘soft spot’, it is the only soft part of the human skull. It is also a normal anatomical landmark present in all newborns. The word ‘fontanelle’ comes from the French word fontaine for fountain.
It is perfectly normal for the diamond-shaped fontanelle to pulsate with each heartbeat. This pulsating action is how the soft spot got its name. The spot on the head is soft, precisely because the cartilage has not hardened into bone between the skull bones.
There are normally two fontanelles and they are both in the midline of the skull. The first is the anterior fontanelle and it is positioned in the front; while the second – the posterior fontanelle – is at the back of the head. The posterior fontanelle closes first by the time the baby turns two months-old, if he or she was born full-term. This is why most mothers don’t know that the fontanelles exist. The anterior fontanelle closes at 18 months of age on the average, but it can also close normally as early as nine months. Indeed, this long time it takes the anterior fontanelle to close is what makes it a subject of concern to mothers. If it closes too early or too late, it means there is a problem.
The fontanelles allow for growth of the brain and skull during an infant’s first year. I shall limit myself to the anterior fontanelle for the purpose of this discussion and it will be used interchangeably with soft spots.
At birth, the fontanelles should feel firm and very slightly curved inward to the touch. This slight depression, which is a normal landmark in infants, has been linked by traditions and customs with so many things like what the Yoruba call oka. Infants with less hair on the head are often victims of this pseudo-diagnosis called oka because the spot is exposed, compared to those with plenty of hair whose soft spots are fully covered. However, if the soft spots are depressed like a well (sunken) or bulging (swollen), you will have to seek medical help.
Causes of sunken soft spots
A sunken or depressed fontanelle is seen in infants with vomiting, diarrhoea or both (which could mean the baby is severely dehydrated). It is also seen among unwell or malnourished infants who may fail to thrive or those who have very low birth weight.
Causes of bulging soft spots
A tense or bulging fontanelle occurs when fluid builds up in the brain or when the brain swells, causing increased pressure inside the skull. When this happens, the soft spots become swollen and can present the following conditions:
Hydrocephalus – This may be as a result of the build-up of fluid inside the skull and increased intracranial pressure.
Encephalitis – This may be due to swelling (inflammation) of the brain, or meningitis (infection of the membranes covering the brain). Immediate, emergency care is needed for any infant who has a truly bulging fontanelle, especially if it occurs along with a fever or drowsiness. Solutions will be offered based on the parents’ responses.
In conclusion, the soft spot is not a cause of diarrhoea, vomiting, cold, sneezing, fever, reduced appetite or weight loss, as perceived and portrayed by traditions and customs. It is not associated with teething or failure of infants to suck breast. Since the soft spots are not a medical condition, it will be necessary to say no medication is required. Nursing mothers are urged to avoid the use and application of herbal concoctions on the soft spots. Again, no scarification marks are needed on the soft spots. In addition, the use of olive oil, methylsalicylate and eucalyptus oil on the soft spots should be discouraged, as they are of no benefit to the infant.
Rotimi Adesanya is a Child and Public Health Physician
You can email him through, email@example.com