DEFINITION
A cranial orthosis is a helmet that is generally custom-made of molded thermoplastic to correct an asymmetrical head shape. It is used for babies, usually before the age of 12 months.
WHY PRESCRIBE A CRANIAL ORTHOSIS
When the head asymmetry is moderate to severe, for physical appearance reasons (cosmesis), it is pertinent to prescribe a cranial orthosis.
With the use of helmets that we must now wear for our safety, for example with motorcycles, for bicycling and for skiing, plagiocephaly is however no longer only a matter of physical appearance.
Ear misalignment is also an important consideration for the potential future wear of vision or sunglasses. In a positional plagiocephaly, it is not unusual to find an ear more anteriorly positioned than the other, and at times higher than the other. To correct such a misalignment, a helmet must be worn prior to 4-5 months of age.
HOW LONG SHOULD THE HELMET BE WORN
For optimal results, the orthosis must be used for 2 to 3 months, 23 hours per day. The less it is worn during any given day, the longer might be the treatment to obtain the same results. The younger the child, the shorter might be the treatment to obtain the same results.
WHEN PRESCRIBE A CRANIAL ORTHOSIS
We often wonder whether the plagiocephaly might self-correct without a helmet. The age of the child at which a helmet is started will influence how long it is worn. Results may also vary depending on the type of the head shape and on the (mal)alignment of the ears. Thus, discussions with the family become even more important.
The helmet must ideally be started before 12 months of age because the speed of head growth slows down after that age. The closer we get to one year of age, the longer the helmet must be worn.
In fact, the helmet is not covered by RAMQ (in the province of Quebec) after 12 months of age.
WHAT SHOULD BE THE TREATMENT BEFORE PRESCRIBING A CRANIAL ORTHOSIS
Before prescribing a helmet, it is better to start with conservative measures as soon as a plagiocephaly is present. Ideally, shortly after birth, these measures can be put in place even before the hint of plagiocephaly. See the blog (to come) on Plagiocephaly and flat heads.
When these approaches are not yielding (enough) results, even in spite of physiotherapy, the helmet then becomes a more evident solution.
POSSIBLE SIDE EFFECTS
Reported side effects are rare. They are generally benign and are usually not severe enough not to prescribe a cranial orthosis. But the helmet must be well made; its fabrication process makes a difference.
Side effects in a systematic review included(1):
- problems accepting the helmet (24%)
- skin irritation (96%)
- increased sweating (71%)
- helmet odour (76 %)
- pain associated with the helmet (33 %)
- feeling hindered in cuddling because of the helmet (77 %)
See the blog Studies on cranial orthoses.
This same study reported difficulties with helmet adjustment: it turned on the head or it shifted on the head a few times a week to several times a day.(1) It is obvious that a poorly fitted helmet that turns on the head will not have the same efficacy as a properly adjusted helmet. The measurement, the fabrication process and the expertise of an experienced orthotist can make a difference (see blog to come – The making of cranial orthoses and parental advice).
WHO CAN PRESCRIBE A HELMET
In the province of Quebec, a prescribing agent authorized by the RAMQ can prescribe orthoses. Physiatrists, neurologists, orthopedic surgeons and neurosurgeons can automatically prescribe orthoses. When these specialists are not present in a given region of the province, a request can be made with the RAMQ, if a medical doctor would like to be involved in the assessment and treatment of plagiocephalies.
Based on where you are in the province of Quebec, the prescribing doctor can be a family doctor, a paediatrician, a physiatrist or a neurosurgeon. The referring physician should seek to know where to refer in his/her specific region. Ideally, the assessing doctor should also evaluate the torticollis, if present, rule out causes other than positional plagiocephaly for the cranial shape and be able to do a full neurodevelopmental review.
NOT TO BE MISSED
Not to be missed are craniosynostoses (premature head suture closure), cervical or dorsal malformations, genetic syndromes, neurodevelopmental delays and ocular causes for the torticollis. A referral to a medical specialist would then be indicated.
MY OPINION
The helmet works well and provides excellent results.
I prescribe the helmet for moderate to severe plagiocephalies in children under 11 months of age and for whom:
- a craniosynostis has been ruled out
- I assess that the plagiocephaly will not sufficiently improve before age 12 months
- other measures only allowed for partial improvement of the plagiocephaly.
I encourage cervical/neck exercises as explained by the physiotherapist, if there is a torticollis.
It is rare that families will insist on a helmet when the plagiocephaly is mild and if the child is less than 7 to 8 months of age. We then have an informed discussion: most mild plagiocephalies will naturally improve on their own without needing a cranial orthosis. I am of the opinion that a frank discussion with the parents, while keeping in mind the medical history, including development, and an in-depth neuromusculoskeletal physical examination help guide clinical decision, which then becomes appropriate for the specific situation of the child.
REFERENCES
1. van Wijk RM, van Vlimmeren LA, Groothuis-Oudshoorn CGM, Van der Ploeg CPB, IJzerman MJ, Boere-Boonekamp MM. Helmet therapy in infants with positional skull deformation: randomised controlled trial. 2014;348:g2741.