Back to Conditions & Treatments by Subspecialty

Occipital Plagiocephaly

September, 1999
Your child has occipital plagiocephaly (OP), a condition in which the occiput (or the back part of the head) is flattened. In most of these infants, the forehead on the affected side is also somewhat prominent, the ear on the affected side is pushed forward compared with the other side, and even the cheek may be somewhat prominent compared with its counterpart. These changes are best appreciated by looking down on your child's head from above. Most pediatric neurosurgeons around the country are seeing a large (and growing) number of these children. We have developed this brochure to answer the most common questions about this condition.

How did my child get this way???

Normally, the head at birth is an oval shape and is reasonably symmetrical - that is, the right and left sides of the head are pretty much identical. If you could draw a box around the infant's head, it would be a rectangular shape (Figure 1). The skull is basically made up of five plates - two frontal bones, two parietal bones, and an occipital bone. These plates are joined by skull sutures. Kind of like the expansion joints between slabs of cement in the sidewalk, these sutures allow movement between the developing skull bones and, more importantly, allow the bones to accommodate as the child's head increases in size during development. There are five important sutures - two coronal, one sagittal, and two lambdoid sutures. Occasionally, one or more of these sutures can close prematurely, a condition known as craniosynostosis. When examined under a microscope, the suture in craniosynostosis is completely closed along part or all of its length.

In the past, doctors recommended that infants sleep on their bellies. As most parents now know, doctors currently recommend that all infants, when they lie down, should be placed on their backs during the first several months of life to prevent sudden infant death syndrome, or SIDS. Unfortunately, although this works well to decrease the chances of your child having SIDS, it also seems to place some pressure on the occiput (the back of the head). Over several weeks or months, this pressure gradually molds the infant's skull, as shown in the following diagrams. The occiput becomes flattened, the ear on that side sometimes gets pushed slightly forward, and even the forehead and cheek on that side can become more prominent. The result (see Figure 1) is that the child's head, which was previously symmetrical and around which you could draw a rectangle, now becomes distorted (and around which you could now draw a parallelogram).

Effect of molding to produce occipital plagiocephaly: On the left is an illustration of a normal infant head, with the skull sutures identified. The ears and skull shape are symmetrical. With continued presure from lying on the back of the head (arrow), the infant skull becomes progressively deformed. The rectangle seen on the left becomes a paralellogram on the right. The right illustration shows right occpital flattening, prominence of the right forehead, and anterior (forward) shifting of the right ear with respect to the left. Lambdoid perisutural sclerosis is indicated by the shading.

Most normal infants, when placed on their backs, spend most of their time (80%) with their heads turned toward the right, 10% of their time turned to the left, and only 10% of the time with their heads turned straight ahead. It is no surprise, then, that a recent study found that 80% of infants with OP had right occipital flattening, and the side that the child prefers to look almost always corresponds to the side of the flattening! At the extreme, a few infants have tight neck muscles which cause them to keep their heads turned constantly to one side, a condition called torticollis. These babies have an even worse problem in that their heads are constantly turned to one side. Over 80% of infants have normal head shapes at birth, but develop OP over the first several weeks of life because of positioning or torticollis.

A minority of babies have OP at the time of delivery. In these babies, the head is probably molded while the baby is still in the womb, perhaps because of 'uterine crowding' due to twinning, a small or 'Y' shaped womb, or because of the way the baby was oriented in the womb. If your baby had OP as a newborn, please be reassured that there is nothing you or your doctor could have done to prevent this.

As the pressure on the occipital bones continues, the bone (which, after all, is a living breathing thing) begins to react to this stress by forming a little ridge of bone near the lambdoid suture. This is called peri-sutural sclerosis. In some cases, the suture can be difficult to see because of this bony build-up. On X-rays and even CAT scans of the skull, these changes can look like the lambdoid suture has closed prematurely, which has led some doctors to call this condition lambdoid craniosynostosis. However, a study by a group or researchers at Toronto's Hospital for Sick Children showed that this is not craniosynostosis.

True lambdoid craniosynostosis does exist, but is extraordinarily rare (representing only 4% of cases of craniosynostosis). True lambdoid synostosis usually creates a trapezoidally shaped head, rather than the parallelogram head shape caused by OP.

What needs to be done about OP???

The first question one might ask is, what is the purpose of treating these children - in other words, what are the consequences of having this disorder? In virtually every case, OP is simply a cosmetic disorder - there is no evidence that OP functionally restricts brain growth, nor that it causes brain damage, intellectual impairment, or developmental delays. Once the child is able to sit and stand, the molding forces are removed and the deformity begins to improve. Although it may not resolve completely, the remaining occipital flattening is usually minor and is not visible because it is covered with hair as the child grows. The frontal differences are minimal and tend to resolve completely with time.

A variety of treatments have been suggested for infants with OP. The simplest, and the most frequently recommended, treatment is to simply place the infant with its head turned toward the opposite side of the head. This can be achieved by placing a towel roll or rolled up blanket beneath the back on the flattened side, and by placing interesting things for the child to look at on the opposite side of the bed. Many infants will squirm off of the roll in a short time; some neurosurgeons recommend using Velcro or tape to secure the roll to the infant's body. Commercial products such as the Prop-a-Bye Baby (Dex Products) may work in early infancy, but are usually outgrown by 4 months of age. Moreover, the American Academy of Pediatrics has recommend not lying in the straight side position, and the use of side-lyers has fallen out of favor.

Many pediatric neurosurgeons have used this simple treatment for years with great success, particularly if the treatment is begun early (before the child reaches 6 months). A recent study by a group in Phoenix showed that children with mild or moderate deformities treated with simple positional changes had about a 50% measured improvement.

Others have proposed molding helmets or head bands - specially constructed and individually tailored plastic helmets which gently mold the infant's skull back into place. One study from the same group in Phoenix using head bands in selected children reported that, on average, the children improved by about 45% - not very different than the results obtained after just changing the children's position! Moreover, although these devices are generally well tolerated, they are more expensive and have the potential for complications including skin breakdown and irritation.

Still others have (primarily in the past) suggested surgery with the belief that these infants had lambdoid craniosynostosis. Physicians now understand that the underlying problem is the infant's sleeping position rather than craniosynostosis, so surgery is now being offered only rarely and for children with very severe deformities. One group evaluated the outcome following one type of operation (removing one lambdoid suture) for this condition and found about a 33% improvement - again, no better than the simple positional changes described above. More extensive operations that remodel the entire back of the head may offer better results, but of course involve greater risks as well. Potential complications of surgery including brain injury, stroke, bleeding, and death.

Pediatric neurosurgeons have adopted a very conservative approach for most children with this problem, believing that children with mild or moderate deformities need nothing more than to change the child's position. Many children with OP have been treated with the simple changes in position described above, and this works about as well as anything else. A minority of children may benefit from molding helmets or surgical treatments; you should discuss these options carefully with your doctor.

Pediatric neurosurgeons are continuing to evaluate the results of various treatments objectively. Hopefully, armed with the right information, we will be able to recommend the best treatment for these infants.

If you or your family have any further questions about occipital plagiocephaly or its various treatments, please contact your pediatric neurosurgeon, or send an e-mail to the Neurosurgery Editorial Staff at mdias@chob.edu.