From the Guidelines
Plagiocephaly does not typically result in a large head circumference. Plagiocephaly refers to an asymmetrical flattening of one side of the skull, which causes a misshapen appearance but generally does not affect the overall size of the head. The condition is most commonly positional, occurring when an infant spends too much time in one position, creating pressure on the same area of the skull. While the head may appear distorted with flattening on one side and possibly bulging on the opposite side, the actual circumference measurement usually remains within normal range for the child's age and development.
The skull's volume stays consistent despite the change in shape. This is because plagiocephaly affects the distribution of skull growth rather than causing excessive growth overall. Some key points to consider include:
- Positional plagiocephaly can be associated with a supine sleeping position, as noted in studies such as 1 and 1.
- Supervised, awake tummy time is recommended to facilitate development and minimize the development of positional plagiocephaly, as suggested by 1.
- In severe cases, regular head circumference monitoring is recommended during treatment, which typically involves repositioning techniques, physical therapy, or occasionally helmet therapy to guide proper skull development.
It's also important to distinguish between plagiocephaly and other conditions that may affect head size, such as macrocephaly, which is a generalized increase in size of the head, as discussed in 1. However, the primary concern with plagiocephaly is the asymmetrical shape of the skull, rather than an overall increase in size.
From the Research
Plagiocephaly and Head Circumference
- The relationship between plagiocephaly and head circumference is not explicitly stated in the provided studies 2, 3, 4, 5, 6.
- However, study 6 mentions that stereophotogrammetry can be used to analyze various distances, including head circumference, in infants with positional plagiocephaly.
- The study 6 found that molding helmet therapy can improve skull asymmetries in infants with positional plagiocephaly, but it does not specifically address the effect on head circumference.
- Study 2 mentions that physical examination of infants with head shape deformities is essential, but it does not provide information on head circumference.
- There is no direct evidence in the provided studies to suggest that plagiocephaly results in a large head circumference 2, 3, 4, 5, 6.
Head Shape and Asymmetry
- Plagiocephaly is characterized by an asymmetric deformation of the skull, which can be measured using various methods, including diagonal calipers 3 and stereophotogrammetry 6.
- The studies suggest that physiotherapy, repositioning, and molding helmet therapy can improve skull asymmetries in infants with positional plagiocephaly 4, 5, 6.
- However, the effect of these treatments on head circumference is not explicitly stated in the provided studies 2, 3, 4, 5, 6.