What Is Sagittal Craniosynostosis?

Sagittal craniosynostosis is a type of craniosynostosis, a common birth defect that causes the bones in a baby’s head to fuse prematurely. The bones in your child’s skull are connected by joints called sutures. These sutures usually stay flexible until your little one’s second birthday, giving their brain room to grow.

When your baby is born with craniosynostosis, one or several of their sutures fuse together, causing the skull to be misshapen. As the brain grows, your baby may experience increased intracranial pressure as well. Craniosynostosis occurs in one of every 2,500 live births.  

Sagittal craniosynostosis describes a fusion of the sagittal suture, which runs from the front of the head to the back. This is the most common type of craniosynostosis, and is usually visible at birth or shortly after.

Sagittal craniosynostosis is most often treated with surgery and close follow-up care. Early diagnosis and treatment can help prevent long-lasting complications. 

Types of Craniosynostosis

Sagittal craniosynostosis is the most common type of craniosynostosis. There are other types of craniosynostosis, including:

• Coronal craniosynostosis: This affects one or both of the coronal sutures, which run from each ear to the top of the head. This type of craniosynostosis causes the forehead to appear flattened and bulging on the affected side.
• Metopic craniosynostosis: This type of craniosynostosis affects the metopic suture, which runs from the top of the bridge of the nose up to the top of the head. It causes the forehead to look triangular and widens the back of the head.
• Lambdoid craniosynostosis: This rare type of craniosynostosis affects the lambdoid suture. This suture runs along the back of the head, and premature fusing causes one side of the head to appear flat and one ear to be higher than the other.

Sagittal Craniosynostosis Symptoms

The classic sign of sagittal craniosynostosis is a long, narrow head.

Bone growth in a baby’s skull is directed away from the suture lines. Because the sagittal suture runs across the top of the head from front to back, it allows for the skull to grow wider.

When this suture fuses prematurely, skull growth stops growing wider, but continues to grow from front to back. This results in a long, narrow head with a full (bossing) forehead. 

Common symptoms of sagittal craniosynostosis include:

• A full forehead and a cone-shaped head
• A disappearing soft spot, or fontanel, on the top of your baby’s head
• A hard ridge along the sagittal suture on the top of the head
• Slowed head growth while the body continues to grow

Rare symptoms may include:

• Sleepiness or fatigue
• Irritability and crying
• More prominent scalp veins
• Poor feeding
• Projectile vomiting

Causes

Most cases of sagittal craniosynostosis are considered random and do not have a known cause. This birth defect may be caused by a combination of genetic and environmental factors. 

While we still do not understand the exact causes of sagittal craniosynostosis, some risk factors appear to raise a baby’s risk of having this birth defect. 

The following risk factors are associated with sagittal craniosynostosis:

• Multiple babies in one pregnancy, such as twins or triplets
• Large head size in utero 
• Maternal thyroid disease
• Maternal smoking
• Fertility treatments such as Clomid (clomiphene citrate)

Sagittal craniosynostosis may also be a symptom of a genetic disorder. Genetic disorders associated with sagittal craniosynostosis include:

• Apert syndrome is a genetic disorder that causes premature fusing of the bones in the skull, as well as in the fingers and toes.
• Beare-Stevenson syndrome is a genetic disorder that causes skin abnormalities and premature fusing of the skull bones.
• Crouzon syndrome is a genetic disorder that affects the bones, muscles, joints, and cartilage. It often leads to the premature fusing of several sutures in the skull.
• Jackson-Weiss syndrome is a genetic disorder that causes foot abnormalities and premature fusing of the skull bones.
• Muenke syndrome is a genetic disorder that causes the premature fusing of the coronal suture, as well as other areas of the skull.
• Pfeiffer syndrome is a rare genetic disorder that causes a baby’s skull bones to fuse together.

Diagnosis

Sagittal craniosynostosis is usually diagnosed with a physical exam. The abnormality is often spotted at birth because the skull malformation can be very pronounced.

To assess your baby for sagittal craniosynostosis, your doctor will examine their head, feeling along the sagittal suture line for a hard ridge. Your doctor will also feel your child’s fontanel to determine if it has closed. 

Your doctor will ask several questions about your family history and pregnancy, which may include:

• Does craniosynostosis run in your family?
• Do you have any family members who were born with a skull abnormality?
• Do you have a family history of any genetic disorders?
• Did you have any complications during your pregnancy?
• Did you require fertility treatments to conceive?
• Do you have a history of thyroid disease or smoking?

Once your doctor has conducted a thorough physical and history, they may order a computed tomography (CT) scan of your baby’s head. A CT scan with 3D reconstruction is considered the most accurate way to diagnose sagittal craniosynostosis. This test can show your child’s sagittal suture, as well as any abnormalities in the brain.

If your doctor suspects that your child’s craniosynostosis is part of a genetic disorder, they will refer you for further testing.

Treatment

Treatment for sagittal craniosynostosis usually involves surgery to both correct the skull malformation and to relieve any increased pressure on the brain. The type of surgery chosen will depend on how old your child is, as well as how severe their craniosynostosis is.

The types of surgery used to treat sagittal craniosynostosis include:

• Endoscopic craniosynostosis surgery: During this procedure, the surgeon makes small incisions into your child’s scalp and then uses a small tube called an endoscope to move the skull bones into place. This type of surgery is often considered for babies who are 2 to 4 months old because their skull bones are still flexible enough to be moved with an endoscope. After surgery, babies must wear a custom-fitted molding helmet for several months to encourage the skull to grow into a more circular shape. 
• Calvarial vault remodeling: During this procedure, the surgeon makes an incision in your child’s scalp and then moves the skull bones into a circular shape. This surgery is usually recommended for babies older than 6 months because their skull bones are thick enough to hold their shape once they are moved. 

Timeline

The timeline of your child’s craniosynostosis surgery will depend on when they are diagnosed. Many children are diagnosed at birth because the head already appears long and narrow.

Young infants aged 2 to 4 months are candidates for endoscopic craniosynostosis surgery. After surgery, they will need to wear a molding helmet for several months.

Babies older than 6 months usually undergo calvarial vault remodeling surgery and do not require a helmet.

Prognosis 

Most babies who are treated for sagittal craniosynostosis have successful outcomes without complications. Early diagnosis and treatment are important for treatment success.

When sagittal craniosynostosis is left untreated, babies can experience increased intracranial pressure and long-term complications, including:

• Developmental delays
• Head or facial abnormalities
• Breathing problems
• Vision problems
• Seizures
• Low self-esteem

Coping

When caring for a child with a serious birth defect, it is essential for parents and caregivers to find effective ways to cope. Fortunately, most babies with sagittal craniosynostosis have success with surgery and go on to live healthy lives without complications. Despite this hopeful prognosis, the diagnostic and treatment period can feel grueling for parents. 

Studies have shown that parents of babies with craniosynostosis experience considerable stress, especially when the skull abnormality is noticeable to others. In a 2020 survey, parents reported feeling stressed and angry when they voiced concerns about their child’s head shape but were dismissed by their medical providers. 

To help manage the stress of caring for a child with sagittal craniosynostosis, reach out to a support group for parents in your area. If you do not have access to a local group, seek out an online community. Your medical team may have recommendations. 

It is also natural for parents to feel overwhelmed with the amount of information they must learn about this condition. It may be helpful to take notes at your child’s medical appointments and to always write down your questions ahead of time. Ask your providers who you can call with your questions in between appointments as well. 

Summary

Sagittal craniosynostosis occurs when the sagittal suture that runs from the front to the back of your baby’s head fuses prematurely. This limits the room for the brain to grow and increases the pressure in their head. This condition causes a cone-shaped head. It may be diagnosed at birth or shortly after by symptoms alone.

Frequently Asked Questions

What is sagittal craniosynostosis?

Sagittal craniosynostosis is the most common type of craniosynostosis, a birth defect that affects the flexible joints in your baby’s skull called sutures. Craniosynostosis causes one or several sutures to fuse prematurely, leading to a misshapen skull and head. Sagittal craniosynostosis occurs when the sagittal suture that runs along the top of the head from front to back fuses prematurely.

What causes sagittal craniosynostosis?

Sagittal craniosynostosis is most often considered a random birth defect with no known cause. Researchers believe it is caused by a combination of genetic and environmental factors. In rare cases, sagittal craniosynostosis is caused by a genetic disorder. 

How common is craniosynostosis?

Craniosynostosis is a relatively common birth defect with one case in every 2,500 live births.

What should you expect after craniosynostosis surgery?

Recovery from craniosynostosis surgery depends on several factors, including the type of surgery performed, how severe the skull deformity was, and the age of your child. Surgery can last from one to six hours, and your child will need to stay in the hospital after surgery. If your child had endoscopic craniosynostosis, they will need to wear a shaping helmet for several months afterwards.

A Word From Verywell

Sagittal craniosynostosis is the most common type of craniosynostosis, a birth defect that affects the joints in the skull. Learning that your child has this serious condition causes several emotions in parents, like grief, confusion, and anger. While the process is most certainly overwhelming, it is comforting to remember that with early diagnosis and treatment, your child will likely go on to live a healthy life without any sign of skull abnormality.

Treatment for sagittal craniosynostosis involves surgery to correct the skull’s shape and give the brain room to grow. It is often helpful for parents to seek out sources of support such as a parent group or online community.