Plagiocephaly after Neonatal Developmental Dysplasia of the Hip at School Age.

Developmental dysplasia of the hip (DDH) may require early abduction treatment with infants sleeping on their back for the first few months of life. As sleeping on back is known to cause deformational plagiocephaly, we assessed school age children treated for dislocation or subluxation of the hip-joint in infancy. Plagiocephaly was analyzed by using cephalic index (CI) and oblique cranial length ratio (OCLR) as anthropometric measurements from 2D digital vertex view photographs. Six of the 58 (10.3%) DDH children and only one of the 62 (1.6%) control children had plagiocephaly (p = 0.041). Furthermore, cross bite was found in 14 (24.1%) of the DDH children and in 7 (10.3%) of the control children. Developmental dysplasia of the hip in infancy was associated with cranial asymmetries and malocclusions at school age. Preventive measures should be implemented.