Hi there, I’m Dr Golly and today we’re talking about HEAD SHAPE in newborns and young children. With newborns, it’s very common for babies to have oddly shaped heads, due to their position in the womb, instruments used to help deliver the baby, or bruising and swelling from childbirth. When these occur, most changes resolve spontaneously, within a few weeks. It’s the longer-term changes that we’re going to discuss here.
Although the skull appears to be one large bone, it’s actually made up of multiple small bones, coming together like pieces of a puzzle. If the joining is faulty, or if there’s too much pressure placed on one side of the head, it can lead to an abnormal head shape, or plagiocephaly.
The word plagiocephaly comes from the Greek plagio – which means oblique, slanting or sloping, and cephal meaning head. Let’s jump to the whiteboard and take a look at the puzzle of the human skull and why plagiocephaly occurs.
So the skull is basically made up of 2 frontal bones, 2 parietal bones which make up the sides and roof, then 1 occipital bone which closes off the back and base of the skull. The reason why we have this jigsaw design is so that the bones of the skull can actually overlap slightly, which can happen during the birthing process, making the head slightly smaller, to fit through the birthing canal. This degree of flexibility also allows for future growth of the brain, because a baby’s brain will quadruple in the first 2 years of life!
Now, all of these puzzle pieces are held together by a fibrous material, like Velcro, which we call sutures. So where the bones meet, it forms a line, or suture, and where the sutures meet, forms a small gap, which we call a fontanelle, or soft spot. There are two major fontanelles in a baby’s skull – the anterior fontanelle, and a slightly smaller fontanelle toward the back. There are 2 more, very small fontanelles on either side of the head.
As a paediatrician, you’ll often see me reaching for the front fontanelle of a baby – we call this the paediatrician’s handshake! This is because we can use this soft spot, to get a truckload of information from your baby. In addition to your baby’s heart rate and level of hydration, we can also look for concerning signs, like if the soft spot is (pointing to 4 corners of the screen) sunken, bulging, unusually large or closing too early.
It’s normal for the fontanelle to slope down slightly, but a very deeply sunken fontanelle may be a sign of dehydration, especially if your child is unwell with fluid loss, not drinking adequately or overheated.
A bulging fontanelle is normal when babies cry, vomit or lie down, but it should go back to normal when your baby is upright and relaxed. In terms of fontanelle size and closure, there is huge variability in what is ‘normal’ and it’s important that each baby is properly examined. Usually the back fontanelle closes by 2 months and the front by 2 years. The sutures only close well into adulthood.
It’s important to be gentle with a fontanelle, but don’t be scared of touching or knocking it. There is a tough protective layer over the brain, as well as the skin, so feel confident to touch the head and wash or brush your baby’s hair.
Did you know that in the first 2 years of life, the brain grows to 75% of its final adult size? This means that the skull is constantly enlarging and changing shape during infancy. It also means the skull is soft and can be moulded with ease. Flattening of the skull in one area can occur from repeated pressure on that side. That is most often due to a preferred sleeping position, or restricted neck movement. Let’s jump to the whiteboard and take a closer look.
Flat spots can occur if a baby spends too much time facing in one particular direction during sleep. This can be due to something that grabs their attention when put to sleep, or due to restricted neck movement, called torticollis. When repeated pressure is placed on one spot of the head, it causes that spot to flatten. When this continues, the front of the skull will start to protrude forward on the same side. While this doesn’t cause any pressure on the underlying brain, it can be severe enough to change the position of the ears and eyes, making a big change to your baby’s appearance.
Luckily, most babies with mild flattening will resolve by themselves, without any treatment at all. The skull can continue to remodel up to the age of 2 years. So if you see a flat spot on your baby, here are some things you can do to correct it:
- Vary your baby’s head position when they sleep and alter which direction their head is, each time you put them into their cot or bassinet. You can prompt looking in one particular direction by placing a picture on the wall too.
- When awake, encourage as much play time on their tummy as possible. This will improve head control and enable them to vary their own head position during sleep.
- You can also vary the way you hold your baby throughout the day, to ensure they don’t spend too much time in any one position (baby sling, upright, over the arm, etc).
Only a very small number of babies will have a persistent deformity, requiring more treatment, which may be in the form of helmet therapy. This helps to reshape the skull by taking pressure off the flat area to allow more symmetrical growth, but this is very seldom required. If you have any concerns regarding your baby’s head shape or appearance, have them seen by your local doctor or paediatrician, sooner rather than later.
So remember, babies’ heads always change shape, and by rotating your baby in their cot for each sleep, you can prevent flattening on one side and ensure a nice, symmetric head shape – which is especially important for us guys — who tend to go bald in older age!
Thanks for watching – I’m Dr Golly, I’ll see you next time.