Helmet Therapy at 12 Months of Age
At 12 months of age, helmet therapy can still effectively improve head shape in infants with moderate to severe positional plagiocephaly, though earlier initiation yields better outcomes. 1, 2
Evidence for Effectiveness at 12 Months
Helmet therapy remains effective even when initiated after 12 months of age, with no statistically significant difference in time to correction compared to younger infants (under 3 months), based on a large retrospective study of 1,050 cases. 3
Infants treated with helmet therapy in the older age group (>12 months) achieved improvement in skull shape within the same treatment interval as younger infants, with an overall correction rate of 81.6% regardless of age at presentation. 3
However, earlier initiation of helmet therapy during infancy consistently produces superior outcomes, with better correction and even normalization of head shape compared to later treatment. 1, 2, 4
The duration of helmet therapy correlates positively with age at initiation, meaning a 12-month-old infant will require a longer treatment period than a younger infant to achieve similar results. 1, 2
When to Recommend Helmet Therapy at This Age
Helmet therapy at 12 months is specifically indicated for:
Moderate to severe plagiocephaly presenting at this advanced age, even without prior conservative treatment attempts. 2, 4
Persistent moderate to severe deformity despite 2-3 months of physical therapy and repositioning (though at 12 months, this trial may have already occurred). 4
Cases where faster correction is desired, as helmet therapy achieves more significant improvement in a fraction of the time compared to conservative therapy alone. 1, 2
Critical Nuance: Conflicting Evidence
One high-quality randomized controlled trial (the HEADS study) found no difference between helmet therapy and natural course at 24 months follow-up in infants starting treatment at 5-6 months of age. 5 This study reported equal change scores for plagiocephaly (mean difference -0.2,95% CI -1.6 to 1.2) and brachycephaly (0.2,95% CI -1.7 to 2.2) between groups, with full recovery in 26% of helmet-treated versus 23% of natural course infants. 5
However, the Congress of Neurological Surgeons guidelines prioritize the substantial body of non-randomized evidence (1 Class II RCT, 5 prospective comparative studies, 9 retrospective comparative studies) demonstrating more significant and faster improvement with helmet therapy, especially for severe deformities. 1
Practical Algorithm for 12-Month-Old Infants
For mild plagiocephaly at 12 months:
For moderate to severe plagiocephaly at 12 months:
- Proceed directly to helmet therapy rather than delaying with prolonged conservative treatment, as the window for optimal skull malleability is narrowing. 2, 4
- Avoid the pitfall of dismissing older infants as "too old for treatment"—evidence supports effectiveness through 18 months of age. 3
Important Caveats
All parents in the HEADS trial reported one or more side effects from helmet therapy, though these were not specified as serious. 5
The most recent systematic review (2025) emphasizes that helmet therapy should be individualized based on severity, age, and response to other treatments, acknowledging methodological limitations in available studies. 6
Clinical examination alone is sufficient for diagnosis; imaging is rarely necessary unless clinical findings are equivocal. 1, 2, 4
Long-term follow-up data (ages 2-10 years) demonstrate that children treated with helmets show significantly greater improvement in both cephalic index (p=0.003) and cranial vault asymmetry (p<0.001) compared to repositioning alone. 7