Abstract AIM To establish normative growth charts for cranial sutures and fontanelles and to quantify the prevalence and morphology of accessory sutures during the first year of infancy. METHOD We retrospectively collected 194 head CT scans of infants (between 0 and 12 months) from the New Mexico Decedent Image Database. Using an automated morphometric framework (ISFMA), morphometric parameters such as suture width, length, sinuosity, and fontanelle area were measured. Growth trajectories were modelled using Generalized Additive Models for Location, Scale, and Shape (GAMLSS). Suture closure was quantified using the Suture Closure Ratio (SCR), and accessory sutures were identified and measured by type and age. RESULTS Suture length increased and width decreased with age. The metopic suture exhibited the earliest closure, while other sutures remained largely open throughout the first year. The anterior fontanelle area peaked around 3 months and gradually decreased thereafter. Accessory sutures, particularly the mendosal suture and superior median fissure, were common in neonates but diminished rapidly with age. INTERPRETATION This study provides the first comprehensive morphometric reference for infant cranial sutures and fontanelles. These normative data enhance clinical capacities for diagnosing craniosynostosis, evaluating abnormal skull development, and supporting forensic investigations involving abusive head trauma.

The authors have declared no competing interest.

This research has received funding from the Swedish Research Council (VR-2016-04203, VR-2020-04496 and VR-2020-04724).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Institutional Review Board of the University of New Mexico gave ethical approval for the creation and research use of the New Mexico Decedent Image Database (NMDID). Access to the database was granted upon institutional request. All data used in this study were fully de-identified and derived from deceased individuals. No additional ethical approval was required for this secondary analysis.

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