Summary

In positional plagiocephaly the skull bone itself is normal – the head is flattened by one-sided lying pressure. The cranial sutures are open and mobile. In craniosynostosis one or more cranial sutures are prematurely fused. The brain cannot grow symmetrically, which can lead to characteristic head shapes, in severe cases raised intracranial pressure and developmental delay. Decisive for the distinction are: ear position, frontal bossing, palpation of the sutures and – for certainty – imaging.

How common are both conditions?

Positional plagiocephaly is very common, with a prevalence of 15–20 % in infants under four months, and has increased since the "back to sleep" campaign of the 1990s. Craniosynostosis is much rarer, occurring in about 1 in 2,500 live births, but can take many forms and is associated, in syndromic variants, with gene mutations.

Comparison

The most important distinguishing features

Feature	Positional plagiocephaly	Craniosynostosis
Cause	One-sided lying pressure on pliable skull bones; no suture fusion	Premature fusion of one or more cranial sutures
Frequency	15–20 % of infants up to 4 months	approx. 1 : 2,500 live births
Ear position	ShiftedEar on the flattened side displaced forward and down	Usually symmetric; no ear advancement
Forehead / face	Frontal bossing ipsilateral (same side as flattening), cheek forward	Shape depends on the affected suture: trigonocephaly (metopic), scaphocephaly (sagittal), plagiocephaly (coronal), etc.
Palpation of sutures	Sutures open, soft, no palpable ridge	Bony ridgeor absent mobility along the affected suture
Head circumference	Normal, symmetric growth	May be compensatorily altered; reduced skull volume with multiple sutures
CVAI measurement	Diagnosis and severity by CVAI (> 3.5 % = abnormal, > 6.25 % = severe)	CVAI alone insufficient – 3D CT needed to assess sutures
Torticollis	Often associated (30–50 %): muscular torticollis favours a preferred lying position	Rarely associated; no causal link
Raised-ICP risk	No riskSkull growth unaffected	PossibleEspecially in multisuture craniosynostosis; ophthalmological check needed
Treatment	Physiotherapy, positioning corrections; possibly orthosis (helmet) – KVG covers only physio	Surgical correction (endoscopic or open) in a specialised centre
Prognosis	Normalises spontaneously in > 80 % by the 2nd year; early treatment improves the result	Very good with early intervention; if delayed, risk of raised ICP and cognitive impairment

When to see a doctor?

When should you seek medical assessment?

⚠ These signs require prompt paediatric assessment

Flattened occiput or asymmetry that does not improve in the first 3 months of life
Ear on the affected side clearly displaced forward
Child turns the head in only one direction (suspected muscular torticollis)
Palpable bony ridge along a cranial suture
Asymmetric forehead region, especially one-sided frontal bossing

✓ These signs point rather to positional plagiocephaly

Child freely turns the head in both directions
Head circumference normal for age
No palpable suture ridge, sutures soft
Asymmetry regressing within 4–6 weeks after consistent positioning correction
No ophthalmological abnormalities

Which work-up clarifies the diagnosis?

In most cases an experienced paediatrician or craniofacial surgeon can make the diagnosis clinically. In case of uncertainty or suspected craniosynostosis, the following examinations are used:

Examination	Yield	When?
Clinical measurement (CVAI, calliper)	Quantifies asymmetry; follow-up	Initial examination, follow-up
3D photogrammetry	Objective skull-shape measurement without radiation	With unclear findings, treatment monitoring
Ultrasound of cranial sutures	Suture patency assessable non-invasively; available in expert centres	First imaging when suture fusion is suspected
3D CT (low-dose protocol)	Gold standard: suture fusion directly demonstrable	Confirmation of craniosynostosis before surgery
MRI	Assessment of brain structure, Chiari malformation; no radiation	Complex syndromes, suspected raised ICP
Ophthalmology	Papilloedema as a sign of raised intracranial pressure	In craniosynostosis at least yearly

Treatment pathways

What comes next – depending on the diagnosis?

Positional plagiocephaly: conservative measures first Positioning corrections (supervised tummy time, stimulation from the "weak" side), physiotherapy for torticollis and – from about 4 months in persistent severe asymmetry – helmet therapy. Treatment is outpatient and without anaesthesia. Swiss health insurance (KVG) covers physiotherapy but not the helmet orthosis. More on the page Positional plagiocephaly.

Craniosynostosis: early surgical correction The only causal treatment is the surgical opening and remodeling of the prematurely fused suture. Depending on age, suture and severity, various techniques are used: endoscopic (within the first 4 months), conventional-open (fronto-orbital advancement), distraction. Treatment is performed in interdisciplinary centres oriented towards ERN CRANIO (European reference network). More on the page Craniosynostosis.

Detail page

👶 Positional plagiocephaly

CVAI classification, helmet therapy, physiotherapy, distinction from craniosynostosis, step-by-step approach.

Detail page

🧠 Craniosynostosis

Suture types, surgical methods, syndromes (Crouzon, Apert, Pfeiffer), genetics and interdisciplinary follow-up.

Procedure in Switzerland

How does the work-up proceed in Switzerland?

In Switzerland the paediatrician is the first point of contact. If craniosynostosis is suspected, referral is made to a specialised centre – in German-speaking Switzerland typically to the Children's Hospital Zurich (Kispi), the Inselspital Bern or the Cantonal Hospital St. Gallen. For French-speaking families the CHUV in Lausanne and the HUG in Geneva are responsible.

A referral is possible informally – a medical letter with the head-circumference curve, photos of the head shape (from above, lateral, frontal) and a description of lying habits considerably speeds up triage.

Cost coverage Positional plagiocephaly: physiotherapy is generally covered by KVG; helmet orthoses are generally not covered by KVG (exception: case-by-case decisions). Craniosynostosis: diagnostic and surgical measures are generally covered by KVG. Genetic testing in syndromic forms as well.

References

Mawji A et al. (2013). The incidence of positional plagiocephaly. Pediatrics, 132(2):298–304. PMID 23837186
Wilbrand JF et al. (2012). Prospective analysis of helmet therapy in positional plagiocephaly. J Craniofac Surg, 23(6):2067–72. PMID 23154380
Garza RM & Khosla RK (2012). Nonsyndromic craniosynostosis. Semin Plast Surg, 26(2):53–63. PMID 23372448
van Wijk RM et al. (2014). Helmet therapy in infants with positional skull deformation. BMJ, 348:g2741. PMID 24784879
Proctor MR (2012). Endoscopic craniosynostosis repair. Transl Pediatr, 3(3):247–58.

Unsure which diagnosis applies?

We help with classification and referral to the right centre. Ask us directly – free and without obligation.