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Warning: If you are a parent worried about your child´s head shape, this document will serve you as a guide to ROUGHLY assess your baby´s condition. It should never be used BY ITSELF to issue a diagnostic without accounting for other factors that might affect your particular child´s skull development.

This document is intended to be used by healthcare professionals who understand all factors involved in newborn cranial growth.

How to measure Plagiocephaly


To measure the degree of deformity of a plagiocephaly, we need to measure the 2 diagonales of the head starting from the frontal lobes and using the same angle.


Here we see an example of how to measure the diagonals in a severe case of plagiocephaly. to obtain a meaningful measure, is important to keep the same angle between the diagonals in the way we describe below.


A- Identify the longest diagonal

B- Place one leg of the craneometer on the frontal lobe belonging to the longest diagonal.

C- Turn the other leg of the craneometer until find the longest distance. this means the widest head diameter.

D- Write down the measurement from the gauge.


Visualy notice the angle that form the craniometer to the line Anterio-Posterior. This line goes from the nose to the back of the head, perpendicular to the face.


Now, placing the craniometer leg on the oposite frontal lobe, and with aproximately the same angle, measure the head width.


Write down the craniometer measurement.


Now you just need to calculate the diference between the 2 head diameters. this diference will give you a number between 0 and 40mm.

The current accepted standard is to classify as follows:

0 to 9 mm Mild plagiocephaly
10 to 19 Moderate plagiocephaly
more than 20mm Severe plagiocephaly

We believe this is a very simplistic aproach that doesn't address the real issue:


With the previous question in mind we have developed the following curve as a guidance for parents and doctors to know whether a baby needs an orthotic device or positioning techniques are sufficient to correct the plagiocephaly.

It is based on the remaining cranial growth that a baby has before 2 years of age. Head will continue to grow in size after 2 years of age but the shape is fixed once the fontanelles are closed and that usually happens at 2 years of age.

The curve represents the maximum head deformity that we can correct by positioning and prevention techniques. Those include counter positioning, head counter positioning, Mimos Pillow, Tummy time, cot counterpositioning and baby carriage.

Please understand this is just a general guideline based on average skull growth. Certain babies ability to recover might vary substantially from this curve. For example the closing of the fontanelles hapens in average at 2 years of age but in some babies this might happen as early as 12 months and others as late as 30 months.

This graph is intended as an extra diagnose tool for specialists who understand cranial growth and development. DON'T USE IT TO ISSUE A DIAGNOSTIC JUST BY ITSELF.

Examples of how to read this graph:

- A baby of 2 months old with a 20mm plagiocephaly although considered by the standard rule as a severe case and in many instances advice to use an orthotic device can be easily corrected with positional treatment.

- A baby of 5 months old with a 16mm plagiocephaly is on the limit of recovery. We have to be extremely strict with positioning and monitor the deformity very closely. if we don't manage to keep the deformity under the curve in the following months we should use an orthotic band.

- A baby of 12 months and 10mm plagiocephaly is above the curve, meaning that wthout corrective helmet he won't recover completely. A 12 months old baby can recover 4mm of plagiocephaly which will left behind 6mm untreated. Having this piece of information parents can decide whether they want a corrective helmet or not.

Premature babies: Please use Adjusted age, not Chronological age. Count as if the baby was born on the exact due date.