Plagiocephaly is NOT caused by a "soft" or malleable infant head. Debunking another medical myth.

It seems that medical myths die hard. As a scientifically-focused academic surgeon, I have always had a healthy skepticism of medical dogma. For example, there is a long-standing rule that no one should never inject any solutions with epinephrine in areas like the ears, nose, and fingers for risk of impairing blood flow and causing tissue death. Although this sounds logical (since epinephrine causes constriction of the blood vessels), the prohibition has no scientific merit. Most surgeons who operate around the ears and nose, as I commonly do, use dilute epinephrine solutions often to help control bleeding. I have never seen or heard of tissue necrosis from this. There are also a rising number of studies showing that finger blocks with lidocaine and epinephrine are safe, including one from our group in an upcoming publication of the Plastic and Reconstructive Surgery Journal. In spite of overwhelming evidence to the contrary, we can be sure that this medical myth will linger in text books and some outer corners of clinical medicine for years to come.

The subject of plagiocephaly is fraught with many misconceptions or “myths”. There are far too many to comment on in this segment, although I will systematically address them all in time. Some of these are propagated by non-medical or paramedical folks who misunderstand, over-interpret, or confabulate what is known about this condition. I must admit that it is galling at times to read the “expert” advice and explanations offered by certain companies and individuals on the web. Unfortunately, I am often similarly astounded by what is offered up as fact by the medical community itself. In this segment, I will highlight one of these myths- that it is the “soft” or malleable infant head that leads to flattening. The argument goes that the infant’s head is malleable and, when placed on a flat surface, assumes a flat shape that over time becomes more persistent. This is analogous to placing a water balloon on a countertop- the weight of the water immediately deforms the balloon to conform to the flat surface. I have even heard some authors, trying to explain the reason some infants get flat and others do not, suggest that the bones of affected infants are abnormally ossified. Of course, there is no evidence for this type of wild conjecture. A representative sampling of this is found at the following links: (see https://www.youtube.com/watch?v=-L3nd2SX0zI; https://www.youtube.com/watch?v=brxq943JriY; https://sleepcurve.com/treat-prevent-flat-head-syndrome)

While the “soft” head hypothesis may sound compelling and even rational, it is absolutely incorrect for a variety of reasons. First, there is no evidence that infants who develop head flattening have weaker or more spongy bones. Second, if we accept that all infants have “soft” or malleable heads, why is it that only 15-20% of infants placed on their back ever develop clinically-relevent cranial flattening? Wouldn’t we expect this rate to be closer to 100%? Third, and perhaps most damning to this theory, is simple observation. Any parent can test the absurdity of this proposal by simply placing their infant on a flat surface and observing the occipital shape- it will still be round. As part of our research on cranial shape analysis, I have reviewed multiple CT images on infants under 2 month of age who have imaging for incidental trauma. I can assure you that there is no evidence that the infant head deforms to accommodate the flat surface of the scanner bed. The CT image below is an infant 15 days old- there is no appreciable evidence of compensatory head flattening, and no evidence of suture overlap. Unfortunately, this false reasoning is propagated by so many “authorities” on plagiocephaly (including some that I know and respect), that it is has become ground deep into the dialogue of this condition.

The reality is that deformational cranial flattening occurs in a manner that is analogous to how a pumpkin grows flat over time. As the small (and very firm) pumpkin grows against the solid and unyielding ground, the weight of the pumpkin exerts progressively increasing downward force against the ground. As Newton’s 3rd Law predicts, the ground also exerts an equal and opposite force to the area of the pumpkin. The pumpkin is forced to grow in the areas of least resistance, i.e., areas where the pumpkin does not contact the ground. Over time, the pumpkin becomes heavier and heavier and grows flatter and flatter as the rising counterforce from the ground displaces growth away from the contact area.

This simple analogy explains why most parents report seeing the flattening around 6-8 weeks, as it takes that long for it to develop. Some specialists have suggested that cranial asymmetry present at birth can propagate into worse flattening over time (see https://www.youtube.com/watch?v=-L3nd2SX0zI). Several studies have debunked this myth as well (see text of suggested readings). Infants that start with cranial asymmetry at birth are not the ones who become flat later in infancy.

What does all this mean for parents of a newborn or infant with flattening? On the most basic level, it is important that anyone dealing with infants affected by plagiocephaly, whether as a parent or a clinician, to understand the basic mechanism by which this occurs in order to derive a strategy to prevent if from happening. The overarching principle of prevention or early treatment is to redistribute the counterforce on the head. This can be done in two ways- repositioning the head so that there is not one consistent contact area, or changing the resting surface so that the force is distributed across a greater surface area. Reposition is recommended by the American Academy of Pediatrics, but this is a very difficult strategy to employ. First, as a parent of four kids I can attest that few if any new parents are willing (or able) to wake up every 1-2 hours and risk waking a sleeping infant by moving their head. It is a recommendation that is impractical. Second, and perhaps most damning for this strategy, is the fact that the largest group of at-risk kids for flattening are those with torticollis. I am sure repositioning strategies work great to prevent flattening in infants who are low risk (i.e., those without torticollis) and would never have developed flattening anyway. But for infants with torticollis, it is nearly impossible to get them to maintain a head position. Parents of affected infants seen in my practice tell me the same story- they would try repositioning, but that the baby would immediately go back to the same head position. This, my friends, IS torticollis! As I have reiterated in all of my work in this subject- ANY INFANT WHO CONSISTENTLY FAVORS A SPECIFIC HEAD POSITION HAS TORTICOLLIS. For this group who are actually at risk for getting flat, repositioning is a very ineffective and inefficient prevention or treatment strategy.

This brings us to the second way to prevent or treat plagiocephaly- alter the sleeping surface so that the contact area is broader. This, in my opinion, is the easiest and most efficient way of preventing the development of head shape flattening. By changing the shape of the sleep surface from a flat one to a concave surface, the force imparted by the head on the bed (and the bed to the head) is distributed over a much broader area. If we go back to the pumpkin analogy, it would difficult to conceive of how a pumpkin could get a flat spot if it were grown in a large, expanding contoured bowl. There are many sleep surfaces now on the market, but only two (see studies below) have any actually clinical evidence to support their effectiveness or utility. I find it remarkable that many of these product manufacturers, with no clinical evidence, have the audacity to tout themselves as preventing or treating plagiocephaly. Such assertions are in stark violation of FDA regulation unless validated through a formal process. I am unaware of any that has completed such a review. Moreover, most of these devices are free pillows that are placed behind the infant’s head against AAP recommendations to avoid placing loose items in with the baby. Many parents come into my office with piles of orthotics pillows that failed to do anything for their infant’s head shape. One could easily predict that these pillows would fail to help or prevent head flattening. Why? None of the products adjust as the infant’s head grows- this is the “one-size-fits-none” approach. In addition, none has a concave shape that is even remotely similar to that of a normal infant occiput (posterior head). While a small indentation may be better than a flat surface, it is a long way from ideal. Lastly, the vast majority put the infant’s head in a flexed position which is potentially harmful for the airway. Stay tuned for my detailed segment on these products and their shortcomings. The following are citations for studies on the two resting/sleep surface devices that have some evidentiary support.

Seruya M, Oh AK, Sauerhammer TM, Taylor JH, Rogers GF. Correction of deformational plagiocephaly in early infancy using the plagio cradle orthotic. J Craniofac Surg. 2013 Mar;24(2):376-9. (study of the PerfectNoggin Infant Mattress, previously sold as the Plagiocradle; significant reduction in head asymmetry especially when started before 10 weeks of age)

Rogers GF, Miller J, Mulliken JB. Comparison of a modifiable cranial cup versus repositioning and cervical stretching for the early correction of deformational posterior plagiocephaly. Plast Reconstr Surg. 2008 Mar;121(3):941-7. (controlled study with repositioning versus modifiable orthotic cup- the cup had markedly better outcomes)

Knorr A, Giambanco D, Staude MV, Germain M, Porter C, Serino E, Gauvreau K,, DeGrazia M. Feasibility and Safety of the Preemie Orthotic Device to Manage Deformational Plagiocephaly in Extremely Low Birth Weight Infants. Adv Neonatal Care. 2019 Feb 1. (study in neonates using smaller version of the PerfectNoggin Infant Mattress, formerly sold as the PlagioCradle. Show it to be safe and effective for this high-risk group).

Knorr A, Gauvreau K, Porter CL, Serino E, DeGrazia M. Use of the Cranial Cup to Correct Positional Head Shape Deformities in Hospitalized Premature Infants. J Obstet Gynecol Neonatal Nurs. 2016 Jul-Aug;45(4):542-52. (study in neonates using smaller premie-version of the PerfectNoggin Infant Mattress, formerly sold as the PlagioCradle; restored head symmetry in 83% of hospitalized premies with established head flattening).

DeGrazia M, Giambanco D, Hamn G, Ditzel A, Tucker L, Gauvreau K. Prevention of deformational plagiocephaly in hospitalized infants using a new orthotic device. J Obstet Gynecol Neonatal Nurs. 2015 Jan-Feb;44(1):28-41. (study in neonates using smaller premie-version of the PerfectNoggin Infant Mattress, formerly sold as the PlagioCradle; no safety issues and better head symmetry than standard moldable device)

Sillifant P, Vaiude P, Bruce S, Quirk D, Sinha A, Burn SC, Richardson D,, Duncan C. Positional plagiocephaly: experience with a passive orthotic mattress. J Craniofac Surg. 2014 Jul;25(4):1365-8. (non-controlled study of mattress)