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Three Part Question

In [infants with positional plagiocephaly] is [helmet therapy]associated with [improved skull shapes]?

Clinical Scenario

You are a paediatric registrar in a clinic. A mother comes in concerned about the shape of her 6-month-old infant’s head. She has previously been advised that counter-positioning and physiotherapy might help. She has heard from a friend about using helmets to correct the head shape. She wants to know if this therapy would benefit her child.

You wonder if there is any evidence for the use of helmet therapy in correcting positional plagiocephaly.

Search Strategy

Multiple databases using Dataquest and Proquest search engines were searched.

A Cochrane Library search revealed no articles.
"Positional Plagiocephaly" AND "Helmet"

Search Outcome

34 articles. We found a systematic review entitled "Conservative interventions for positional plagiocephaly".1 Seven papers were relevant to the search. Four of these were included in the systematic review, while the other three were subsequent publications.

Two studies (Loveday,Vles) had a comparative study design where the effect of helmet therapy was compared with counter positioning with or without physiotherapy. Details of relevant papers are shown.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Kelly et al, 1999, USA	258 with cranial vault asymmetry treated before 1 year of age. In addition 246 patients (92%) exhibited concurrent skull base asymmetry and orbitotragial depth asymmetry.	Retrospective	Reduction of asymmetry: cranial vault asymmetry, skull base asymmetry, orbitotragial depth asymmetry	Initial severity of asymmetry was significantly associated with the amount of correction (p>0.001). Total treatment time did not significantly contribute (p>0.5) to the amount of correction.	Dynamic orthotic cranioplasty was used. Mean age at start of treatment was 6.5 months with average treatment for 4.1 months
Vles et al, 2000, The Netherlands	105 infants were recruited in the study. 85 patients received helmet therapy.	Prospective	Cosmetic outcome score (score by parents on a scale of 0–10): 0: severely abnormal -10 normal	Improvement was significantly better and faster in the helmet group compared with non-helmet treatment (p<0.01 and p<0.001, respectively). No correlation was found between the age treatment started, duration of helmet treatment, and degree of improvement. Improvement was maximum in infants with the most severe deformity.	Soft orthoplastic helmet used. Average time of use of helmet was 5.1 months. Subjective assessment and lack of randomisation were the major drawbacks of the study.
Loveday et al, 2001, New Zealand	74 infants, 45 managed with active counter positioning and 29 with orthotic helmets	Prospective	Improvement in the cranial vault asymmetric index	In infants managed with active counter positioning, the average change in the cranial vault asymmetry index was 1.9% in contrast to 1.8% in the orthotic group. The management period in the orthotic helmet group was found to be approximately three times shorter.	Cranial index and cranial vault asymmetry index were obtained from two dimensional head tracings. The helmet did not fit well on markedly brachycephalic skulls and was occasionally found to cause heat rash and skin injury over pressure points.
Teichgraeber et al, 2002, USA	125 patients met the inclusion criterion.	Prospective	Reduction in cranial vault asymmetry	A 41.56% (p<0.001) reduction in cranial vault asymmetry and a 40.23% (p<0.001) reduction in cranial base asymmetry. Orbitotragial asymmetry was improved 18.72% (p = 0.074). The age at which moulding therapy was begun was not significant in predicting outcome.	A DOC band was used. Cranial vault asymmetry was determined by measuring the distance between the left frontozygomatic point and the right euryon point minus the distance between the right frontozygomatic point and the left euryon point.
Teichgraeber et al, 2004, USA	Of the 292 infants who were treated with moulding therapy, 64 were treated for positional brachycephaly and 248 for positional plagiocephaly.	Retrospective	Forehead asymmetry (FD) was calculated as the absolute difference between measurements from the frontozygomatic junctions to the contralateral euryons. The difference of zero indicated symmetry. The orbital asymmetry (OD) was calculated as the absolute difference between measurements from lateral epicanthi to the ipsilateral tragia. The difference of zero indicated symmetry.	Statistically significant improvements occurred in both FD and OD after treatment with helmet therapy (p<0.01). Age at which treatment was started had no significant effect on outcome.	The moulding helmet used was a dynamic orthotic cranioplasty band. The length of treatment was 4.5 (SD 1.8) months. This study pointed out that plagiocephaly can frequently be normalised but brachycephaly can only be improved.
Bruner et al, 2004, USA	34 children completed the study protocol	Prospective	Three dimensional reconstructions of CT scans were reformatted. Intracranial volumes were calculated on a quadrant basis, and asymmetry was evaluated with regard to hemispheres and posterior quadrants. Efficacy of treatment was measured according to per cent decrease in asymmetry.	A 36–54% improvement in asymmetry in the compliant patients over the 6-month study period	Mean duration of helmet therapy was 7 months. Mean age at initial scan was 6.3 months, and mean age at follow-up scan was 14 months. Radiation exposure was the major drawback of the study.
Lee et al, 2006, USA	75 patients in a tertiary care centre	Retrospective	Ratio of right and left oblique diameters. A ratio of 1 represented a perfectly symmetric cranium	Improved outcomes as compared to pretreatment measurements (p<0.001). No limitation of cranial growth as evidenced by significant normalisation of the oblique measurement ratio when compared to increasing cranial circumference and age (p<0.001 and p<0.001, respectively).	Use of an active moulding helmet made of clear polymer that uses a constant pressure with air bladders. There were no complications due to skin injury from helmet use. Limitations of the study were no subjective measurement of how the helmet was tolerated and no data on how long the helmet was worn each day.

Comment(s)

There has been an increase in the incidence of positional plagiocephaly since the recommendation, in the early 1990s, to place infants on their backs in order to prevent sudden infant death syndrome. Due to incomplete ossification of the skull as well as patent fontanelles and sutures, the infant cranial vault is susceptible to persistent external forces and moulding. Children with positional plagiocephaly have a right or left sided occipital flattening usually associated with prominence of the ipsilateral frontal area resulting in a cranium that is a parallelogram. There is some evidence to show that positional plagiocephaly is a self-limiting condition (Hutchison). There are three primary options for treating deformational plagiocephaly: observation and repositioning, external orthotic helmet therapy, and surgery. Intentional remodelling of cranial bones has been practiced since the seventh millennium BC, when the Egyptians created specifically desired head shapes to suit cultural mores. Clarren et al first introduced cranial moulding principles as an orthotic modality in 1979. Moulding helmets make use of two intrinsic properties of the infant skull: malleability of the cranium and the rapid growth that occurs within the first year of life. Most helmets use a passive approach. They are moulded to allow for growth in the desired areas, having an open space that the head grows into and occupies. There is currently one helmet that attempts to incorporate external forces to assist in positional plagiocephaly correction. The dynamic orthotic cranioplasty band (Cranial Technologies, Tempe, AZ) uses a styrene outer shell held together by elastic bands, which are thought to assist in applying pressure to the growing cranium. However, the consistency and application of the forces exerted by the elastic bands are not currently monitored. In the UK the cost of the helmet is approximately £1700 to £2000, which is a privately funded expense not available on the NHS. The cost includes consultation fees, which in many cases are refundable. At present there is no official RCPCH position on the management of positional plagiocephaly. Currently, the best tool to objectively evaluate deformational plagiocephaly and treatment outcome is anthropometric measurement. Computed tomography can greatly increase the accuracy of measuring the results of helmet therapy but is impractical due to the radiation dosage and the need to sedate infants. Three-dimensional photography may eventually prove useful in quantifying the severity of deformational plagiocephaly and its outcome. The two major flaws in the literature are: The absence of standardised measurements of plagiocephaly, agreed thresholds for treatment, and standardised methods to assess the effectiveness of helmet therapy. None of the reviewed trials have randomisation, with entry into the helmet arm being guided by clinical opinion or other factors. Therefore, any interpretation of the literature must be very cautious indeed. The systematic review of conservative interventions for positional plagiocephaly is also inconclusive (Bailocerkowski).

Clinical Bottom Line

There is no good evidence that for the average infant presenting with a moderate degree of plagiocephaly, helmet therapy will result in a better outcome, when compared with either active repositioning or no therapy. This is particularly of concern given the number of parents placing themselves under significant financial hardship to self-fund this treatment on such paucity of evidence. A good randomised trial is needed. The literature on the use of helmet therapy in positional plagiocephaly largely concerns uncontrolled cohort studies whose outcomes have not clearly shown to be reproducible, valid or precise. (Grade C)

References

1. Bailocerkowski AE, Vladusic SL, Howell SM. Conservative interventions for positional plagiocephaly: a systematic review. Dev Med Child Neurol 2005;47:563–70.
2. Hutchison BL, Hutchison LAD, Thompson JMD, et al. Plagiocephaly and brachycephaly in first two years of life: a prospective cohort study. Pediatrics 2004;114:970–80.
3. Clarren SK. Plagiocephaly and torticollis: etiology, natural history and helmet treatment. J Pediatr 1981;98:92–5.
4. Kelly KM, Littlefield TR, Pomatto JK, et al. Importance of early recognition and treatment of deformational plagiocephaly with orthotic cranioplasty. Cleft Palate Craniofac J 1999;36:127–30.
5. Vles JSH, Colla C, Weber JW, et al. Helmet versus nonhelmet treatment in nonsynostotic positional posterior plagiocephaly. J Craniofac Surg 2000;11:572–4.
6. Loveday BPT, de Chalain TB. Active counter positioning or orthotic device to treat positional plagiocephaly? J Craniofac Surg 2001;12:308–13.
7. Teichgraeber JF, Ault JK, Baumgartner J, et al. Deformational posterior plagiocephaly: diagnosis and treatment. Cleft Palate Craniofac J 2002;39:582–6.
8. Teichgraeber JF, Seymour-Dempsey K, Baumgartner JE, et al. Molding helmet therapy in the treatment of brachycephaly and plagiocephaly. J Craniofac Surg 2004;15:118–23.
9. Bruner TW, David LR, Gage HD, et al. Objective outcome analysis of soft shell helmet therapy in the treatment of deformational plagiocephaly. J Craniofac Surg 2004;15:643–50.
10. Lee WT, Richards K, Redhead J, et al. A pneumatic orthotic cranial molding helmet correcting positional plagiocephaly. J Craniofac Surg 2006;17:139–44.