Children's Hospital Colorado

Craniosynostosis

What is craniosynostosis?

Craniosynostosis is a condition in which parts of a baby's skull fuse together too soon and cause the head to become atypically shaped. 

A newborn's skull is made up of seven major plates of bone separated by sutures, the narrow spaces between the plates. Sutures are where much of the growth of the skull occurs during infancy. Eventually, all of the sutures close as the plates of bone fuse together forming a solid piece of bone. However, most sutures take years to close.

An illustration of a newborn skull showing normal size and placement of the plates.

However, when a baby has craniosynostosis, it means that one or more of the sutures closes earlier than expected. When this happens, skull growth at the closed suture slows down or stops, but the brain keeps growing, which causes an increase in growth in the areas where the sutures are open. This leads to an atypical head shape. In some children, craniosynostosis can affect brain growth and development.

Types of craniosynostosis

Each type of craniosynostosis has its own characteristics. Each type gets its name from the name of the closed suture. 

Below are types of craniosynostosis that we frequently see at the Craniofacial Center at Children's Hospital Colorado. The name of the closed suture is represented in each type (the corresponding head shape is in parentheses.).

An illustration of a baby's skull with the plates fused across the middle and labeled Fused sagittal suture. Next to it is an illustration of a baby's head showing the irregular shape elongating out toward the back.

Sagittal craniosynostosis (scaphocephaly)

  • Long and narrow head
  • Prominent forehead and occiput (back of head)
  • Ridge running from front to back along the top of the head
  • Most common type of craniosynostosis
  • More common in boys than girls

An illustration of a baby's skulls with the two plates on the left side fused together and labeled Fused coronal suture. Next to it is an illustration of a baby's head showing a prominent forehead on the opposite side of the suture, a prominent temporal region near the eye on the fused side, and a deviated nose.

Unicoronal craniosynostosis (anterior plagiocephaly)

  • One eye appears more narrow, while the other eye appears wider
  • One side of the forehead appears more prominent, while the other is flattened
  • Mild curvature to nose
  • Ridge running from the top of the head down one side toward the ear 
  • More common in girls than boys

An illustration of a baby's skull with the front two plates fused together and labeled Fused metotopic suture. Next to it is an illustration of a baby's head showing the skull protruding out in a line down the center of the forehead.

Metopic craniosynostosis (trigonocephaly)

  • Triangular forehead with the eyes close together
  • Ridge running up and down the middle of the forehead 
  • More common in boys than girls 

An illustration of a baby's skull with two plates fused together and labeled as Fused lamboid suture.

Unilateral lambdoid craniosynostosis (posterior plagiocephaly)

  • Flat occiput (back of head) on one side
  • One ear may be further back and down than the other ear 
  • Least common type of craniosynostosis that involves only one suture and is not caused by a known syndrome

What causes craniosynostosis?

Craniosynostosis occurs in babies with and without a family history of the condition. Sometimes, it occurs as part of a syndrome or genetic disorder. There are over 150 genetic syndromes that are known to cause craniosynostosis. 

When craniosynostosis is not part of a syndrome (non-syndromic craniosynostosis), it is usually not inherited, which means that it is not passed from a parent to a child. Most cases of craniosynostosis are non-syndromic. 

A geneticist at Children's Colorado can help your family understand the cause and future risks related to a diagnosis of craniosynostosis.

Who gets craniosynostosis?

Craniosynostosis occurs in about 1 out of every 2,500 newborn babies. There is a 0-4% chance that a sibling born after a child with craniosynostosis will also have the condition. A similar risk exists for children of parents with craniosynostosis.

Get to know our pediatric experts.

Kia Benson, CPNP-PC

Kia Benson, CPNP-PC

Certified Pediatric Nurse Practitioner

Patient ratings and reviews are not available Why?

Richele Koehler, PA-C

Richele Koehler, PA-C

Physician Assistant

Patient ratings and reviews are not available Why?

Andrea Bischoff, MD

Andrea Bischoff, MD

Surgery - Pediatric

Todd Hankinson, MD

Todd Hankinson, MD

Neurosurgery, Neurosurgery - Pediatric