Craniosynostosis

Also known as: synostosis

What is craniosynostosis?

Most babies are born with a skull made up of several bony plates that are not yet fused by bone but are joined together by soft tissue. These lines of soft tissue are called “sutures” or “suture lines”; they allow the head to be flexible and mold as it passes through the birth canal. These sutures normally “close” with a bone when the infant is 2-3 years old. However, when a baby has craniosynostosis, one or more of the skull bones are joined together by bone prematurely. This leads to problems depending on which and how many sutures may have closed early.

What causes craniosynostosis?

The cause of craniosynostosis is sometimes not known. In some cases, it may be a genetic disorder inherited from the parents. Other times, craniosynostosis is a secondary sign of a separate genetic disease.

What are the signs and symptoms of craniosynostosis?

The physical signs of craniosynostosis are usually noticeable at birth, but sometimes can only become apparent during the first months of life. Usually signs include a misshapen skull or a hard ridge can be felt where the bones come together. The baby’s head may also not grow normally (or at all) as your baby ages.

What are craniosynostosis care options?

The mildest forms of craniosynostosis may not require surgery, and your physician might recommend a specially molded helmet that can help to reshape your baby’s head. However, for most babies, surgery will be required to reopen the suture(s) of the skull, allowing room for the growing brain and also improve the overall appearance of the baby’s head.

Reviewed by: Parul B Jayakar, MD

This page was last updated on: September 16, 2025 12:12 PM