Passage through the birth canal often makes a newborn's head appear pointy or elongated for a short time. It's normal for a baby's skull, which is made up of several separate bones that will eventually fuse together, to be slightly misshapen during the few days or weeks after birth.
But if a baby develops a persistent flat spot, either on one side or the back of the head, it could be a sign of positional plagiocephaly. Also known as flattened head syndrome, this can occur when a baby sleeps in the same position repeatedly or because of problems with the neck muscles.
Fortunately, positional plagiocephaly can be treated without surgery and does not cause lasting cosmetic problems.
About Positional Plagiocephaly
Positional plagiocephaly is a disorder in which the back or one side of an infant's head is flattened, often with little hair growing in that area. It's most often the result of babies spending a lot of time lying on their backs or often being in a position where the head is resting against a flat surface (such as in cribs, strollers, swings, and playpens).
Because infants' heads are soft to allow for the incredible brain growth that occurs in the first year of life, they're susceptible to being "molded" into a flat shape.
Causes of Positional Plagiocephaly
The most common cause of a flattened head is a baby's sleep position. Because infants sleep so many hours on their backs, the head sometimes assumes a flat shape.
In almost all infants with plagiocephaly, there is some limit of active neck movement that leads to a preference to turn the head to one side and not to the other. The medical term for this is torticollis.
The cause and effect relationship between torticollis and plagiocephaly goes both ways. Many infants are born with torticollis — perhaps related to fetal positioning in the uterus during late pregnancy — and subsequently develop plagiocephaly after birth.
But infants with severe flattening on one side must expend much more energy than normal to turn the head to the other side, so they do not do so, and their necks become stiff from disuse. In many infants with torticollis, their head will be turned to one side (usually to the right, for unknown reasons) while their chin is tilted toward the other.
Premature babies are more prone to positional plagiocephaly — their skulls are softer than those of full-term babies, and they spend a great deal of time on their backs without being moved or picked up because of their medical needs and extreme fragility after birth, which usually requires a stay in the neonatal intensive care unit (NICU).
A baby might even start to develop positional plagiocephaly before birth, if pressure is placed on the baby's skull by the mother's pelvis or a twin. In fact, it's not at all unusual to see plagiocephaly in multiple birth infants.
If your infant has a misshapen head, your physician will need to decide whether the cause is plagiocephaly, which is very common and does not require surgery, or a condition called craniosynostosis, which is much less common and generally requires surgical treatment.
Craniosynostosis happens when adjacent skull bones become fused together ahead of the normal developmental schedule. This fusion limits the growth of the head in the direction perpendicular to the fused border between the affected bones, and the head grows excessively in other directions. This produces distinctive patterns of skull deformity that look very different from plagiocephaly.
Plagiocephaly is usually easy to recognize, because the deformity affects the back of the head most severely.
Signs and Symptoms
Positional plagiocephaly is usually easy for parents to notice. Typically, the back of the child's head (called the occiput) is flattened on one side, and the ear on the flattened side may be pushed forward as viewed from above.
In severe cases, there may be bulging on the side opposite from the flattening and the forehead may be asymmetrical (or uneven). If torticollis is the cause, the neck, jaw, and face may be asymmetrical. But although other aspects of the head and face may be affected, in positional plagiocephaly the back of the head is always most involved.
Most often, a doctor can make the diagnosis of positional plagiocephaly simply by examining a child's head, without having to order lab tests or X-rays.
The doctor will also note whether regular repositioning of the child's head during sleep successfully reshapes the growing skull over time (craniosynostosis, on the other hand, typically will worsen).
If there's still some doubt, consultation with a specialist — a pediatric neurosurgeon or a craniofacial plastic surgeon — may be needed. X-rays and CT scans play no role in the management of plagiocephaly and are not necessary to distinguish it from craniosynostosis.
Treatment for positional plagiocephaly caused by sleeping position is usually easy and painless, entailing simple repositioning of babies during sleep to encourage them to alternate their head position while sleeping on their backs.
Even though they'll probably move around throughout the night, alternating sides is still beneficial. The American Academy of Pediatrics (AAP) does not recommend using any wedge pillows or other devices to keep your baby in one position.
In addition, you will want to consider how you lay your baby down in the crib. Most right-handed parents carry small infants cradled in their left arms and lay them down with the heads to their left. In this position, the infant must turn to the right to look out into the room — and, indeed, torticollis to the right with flattening of the right side of the head is far more common than the left.
Whichever side of your infant's head is flattened, you will want to position your baby in the crib to encourage active turning of the head to the other side.
Always be sure your baby gets plenty of supervised time on the stomach while awake during the day. Not only does "tummy time" promote normal shaping of the back the head, it also helps in other ways. Looking around from a new perspective encourages your baby's learning and discovery of the world. Plus, it helps babies learn to push up on their arms, which helps develop the muscles needed for crawling and sitting up. It also helps to strengthen the neck muscles.
As most infants with plagiocephaly have some degree of torticollis, a course of physical therapy and a home exercise program will usually be part of the recommended treatment. A physical therapist can teach you exercises to do with your baby involving stretching techniques that are gradual and progressive. Most moves will consist of stretching your child's neck to the side opposite the tilt. Eventually, the neck muscles will be elongated and the neck will straighten itself out. Although they're very simple, the exercises must be performed correctly.
For kids with severe positional plagiocephaly, doctors may prescribe a custom-molded helmet or head band. These work best if started between the ages of 4 and 6 months, when a child grows the fastest, and are usually less helpful after 10 months of age. They work by applying gentle but constant pressure on a baby's growing skull in an effort to redirect the growth.
But never purchase or use any devices like these without having your child evaluated by a doctor. Only a small percentage of babies wear helmets. The decision to use helmet therapy is made on a case-by-case basis (for example, if the condition is so severe that a baby's face is becoming misshapen or the parents are very upset). Although helmets might not improve the outcome in all children, some kids with severe torticollis can benefit from their use.
The outlook for babies with positional plagiocephaly is excellent. As babies grow, they begin to reposition themselves naturally during sleep much more often than they did as newborns, which allows their heads to be in different positions throughout the night.
After babies are able to roll over, the AAP still recommends that parents put them to sleep on their backs, but then allow them to move into the position that most suits them without repositioning them onto their backs.
As a general rule, once an infant has attained independent sitting, plagiocephaly will not get any worse. Then, over months and years, as the skull grows, even in severe cases the flattening will improve. The head will never be perfectly symmetrical, but for a variety of developmental reasons the asymmetry becomes much less conspicuous as well. In later childhood the face becomes more prominent in relation to the skull, hair thickens, and children grow into lives of continual motion. Experience and clinical research have shown that by school age, plagiocephaly is no longer a social or cosmetic problem.
It's important to remember that plagiocephaly itself does not affect a child's brain growth or cause developmental delays or brain damage.
Babies should be put down to sleep on their backs to help prevent sudden infant death syndrome (SIDS), despite the possibility of developing an area of flattening on the back of the head.
However, alternating their head position every night while they sleep and providing lots of tummy time and stimulation during the day while they're awake can reduce the risk of positional plagiocephaly.
Reviewed by: Joseph H. Piatt, MD
Date reviewed: May 2011