Flat head syndrome, also called positional plagiocephaly, develops in babies because of external pressures on the soft, malleable baby skull. It is more common now that babies sleep on their backs, as recommended by SIDS safety guidelines.
While one in five children are affected by flat head syndrome, parents receive mixed messages about whether it has an impact on development, and clinicians don’t have good evidence to allay fears.
Our review published this week shows that while not all children displaying a flat head will experience developmental problems, the syndrome can be used as a marker of potential developmental delay. We make the recommendation that children with flat head be assessed for developmental delays.
What is flat head syndrome and why does it develop?
Flat head syndrome presents as a flattened area on the back or side of a baby’s head. In severe cases it can affect the alignment of the ears, eyes and jaw. It’s typically noticed by the parent up to the fourth month of age. It can be present at birth or develop over time, up to about the 18 month mark when the baby’s skull bones are harder and fixed in place.
The syndrome develops because of external pressures to the soft, malleable baby skull. It’s become more common since 1992, when the SIDS safe sleeping campaign Back to Sleep (now known as Safe to Sleep) began. This campaign saved lives, and continues to do so.
With the need for rigorous information on whether flat head syndrome leads to developmental delay, we reviewed existing medical literature to inform clinicians and parents on the state of knowledge in this area. There were 19 studies that met our strict quality criteria, in which the children’s ages ranged from three months to ten years.
Our review shows flat head syndrome is a marker of developmental delay. Delay can occur in one or multiple areas of development known as domains. For children with flat head, delays were observed most commonly in the motor domain, controlling muscular activities such as walking (gross motor) and holding a spoon (fine motor). The second and third most common delays were observed in language and cognition (such as speaking or understanding one’s own name).
Although we sought to address whether flat head leads to delays, or whether delays are causing flat head, none of the studies conducted to date are able to answer this question. Thus, given there is a link, but the direction is to be determined, we make the recommendation that children with flat head be assessed for developmental delays.
Simple developmental milestones should be met (within the normal variation). When not met, clinicians (GPs, physiotherapists, occupational therapists, nurses) can use standardised assessment tools to more objectively assess the child’s development and refer for early intervention if necessary.
Our review found children with flat head who had developmental delays on multiple domains (such as motor, learning and cognition), or who had low muscle tone, were a special high risk group where intervention and longer-term follow-up would likely be helpful.
Our review found delays were more common in newborn to two-year-olds, but delays did persist to preschool and school aged children in some cases, although there is less knowledge on the older age groups.
Most children with flat head syndrome will be fine
While it is difficult to say with confidence what proportion of children with flat head will experience a developmental delay, it is likely most children with flat head will be fine in terms of their development.
In the studies included in the review, about 10-25% of the children had developmental delays beyond that expected (although the range observed was 3-51% depending on the study). Some studies presented this in terms of risk, and reported children with flat head were up to ten times more likely to experience developmental delays than children without flat head.
How parents can prevent or reduce flat head
The benefits of following the SIDS guidelines far outweigh any concerns about flat head, given death could result from not following safe sleeping recommendations. Babies should be put to sleep on their backs in a firm, flat area, free of toys, pillows or other items, in a non-smoking environment.
Home prevention of flat head syndrome is possible. Tummy time while awake and supervised – a little bit every day starting from birth – can help strengthen neck muscles, and provide time off the back and sides of the head. Altering the position of baby while awake (holding, or in a carrier) is also helpful.
Some children are at heightened risk of flat head syndrome, such as premature babies, those with a challenging birth, or who have torticollis (also known as wry or twisted neck), so you should not feel guilty if your child has a flat head. If concerned at any time, you should seek advice from a health professional. Since babies receive vaccinations at several time points during their first year this can be an opportune time to seek assessment and advice.
Authors: Alexandra Martiniuk, Associate Professor, University of Sydney