Classification and pathogenic models of unintentional postural cranial deformities in infants: plagiocephalies and brachycephalies.

Unintentional postural deformities of the skull have increased in a pseudoepidemic manner in the last 15 years. Although dorsal decubitus and prenatal risk factors can play a role in the genesis of such deformities, we think that a crucial determinant is a postnatal defect of cervical mobility responsible for the infant's posture (ie, positional preference) when supine. Indeed, muscular factors, which limit the range of head and neck movements, have been underestimated in the genesis of skull deformities.