The skull of an infant or young child is made up of bony plates that allow for growth of the skull. The borders at which these plates intersect are called sutures or suture lines. In an infant only a few minutes old, the pressure from delivery compresses the head, making the bony plates overlap at the sutures and creating a small ridge.
This is normal in newborns. In the next few days the head expands, the overlapping disappears, and the edges of the bony plates meet edge to edge. This is the normal position.
Ridging of the suture line can also occur when the bony plates fuse together too early. When this happens, growth along that suture line stops. Premature closure generally leads to an unusually shaped skull.
Premature closing of the suture running the length of the skull (sagittal suture) produces a long, narrow head. Premature closing of the suture that runs from side to side on the skull (coronal suture) leads to a short, wide head.
Normal ridging due to overlap of bony plates after birth
When did you first notice that the skull seemed to have ridges in it?
What do the soft spots (fontanelles) look like?
Have the fontanelles closed? At what age did they close?
What other symptoms are present?
How has your child been developing?
Your health care provider will begin with an examination of the skull to see if there is ridging. If there is ridging, the child might need x-rays or other types of scans of the skull to show whether the sutures have closed too early.
Although your health care provider keeps records from routine examinations, you may find it helpful to keep your own records of your child's development. You will want to bring these records to your health care provider's attention if you notice anything unusual.
Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.