Definition of plagiocephaly
The term “flat head syndrome” is most commonly used to define the asymmetry of the skull of a newborn. We also use the term plagiocephaly to specifically name malformations of the baby’s head. The Greek terms “plagios” & “kephale”, mean oblique & head1.
In clinical practice, a malformation or flattening of the skull is observed by parents or diagnosed by doctors or other specialists around the age of 2 to 3 months2 despite the fact that asymmetries could have already been formed at birth. A diagnosis of plagiocephaly is established by evaluating six references of the anatomy of a baby’s head3. Depending on the severity of the plagiocephaly at least four asymmetries of the skull are easily identified.
- A flat side on the back of his head, for example on the left and on the opposite side of the forehead4
- On the side of the forehead that is flat, the eye is also smaller than the other.
- The ear on the side that is flat at the back of the head has moved towards the face, while the other appears to be behind.
- Globally, the skull looks like a parallelogram when observed from the top5.
The causes of plagiocephaly
The causes of malformation of a newborn’s skull are related to many circumstances that are linked to each other and that can occur before, during and after birth. The position of the child's body and the position of his head in the uterus during the last weeks of pregnancy can already cause a flattening or distortion of the overall volume of the baby's skull. Pressure on the baby's head during his passage through the pelvis of his mother during childbirth and instruments of birth (forceps or vacuum) can also cause cranial asymmetries. A torticollis that limits the rotation of the newborn’s head may also contribute to flattening and deforming the head in its overall volume.
However, the factor that is most often connected to plagiocephaly or the most aggravating is the sleeping position of the newborn7. While his sleeping position aggravates plagiocephaly, it does not explain its appearance8. Most clinical research are now linking the increase in cases of plagiocephaly of the past 10 years and the “Back to sleep” campaign of the American Society of Pediatrics. Since 1992, this campaign has been recommending that parents place the newborn on their back to reduce the risk of sudden infant death9.
Scientific clinical data has evaluated between 13% and 40% the risk for newborn babies under the age of twelve months old to be diagnosed with mild, moderate or severe plagiocephaly10.
The nature of treatments to correct skull malformations has evolved in the past years. From a total absence of treatment, it has evolved to approaches such as cranial and facial surgery, physiotherapy, helmets, positioning tips and osteopathy combined with these approaches11.
In paediatric communities and clinical research, a precocious treatment of plagiocephaly is recognized as key. However, although the importance of beginning treatment early has been demonstrated12, it has been observed that parents and doctors alike sometimes wait for the situation to improve by itself13. The spontaneous or progressive remodelling of the head, in several cases, does not happen14 and delaying the procedure can limit the potential treatment and can increase their severity in absence of intervention.