DESCRIPTION

Plagiocephaly is defined as an asymmetrical head shape due to unilateral flattening. There is also an isolated form of plagiocephaly which is a nonsyndromic craniosynostosis. This occurs when there is premature fusion of one coronal or lambdoid suture, leading to deformity of skull and facial asymmetry.

EPIDEMIOLOGY

• Before 1992, the incidence was 1 per 300 infants. However, with the “Back to Sleep” campaign by the American Academy of Pediatrics (AAP), now called “Safe to Sleep,” the incidence is estimated to have increased 5-fold.
• It is estimated to occur in 15–20% of infants.
• The prevalence is slightly higher in males.

ETIOLOGY

• Deformational plagiocephaly also known as positional plagiocephaly; risk factors include the following:
  • First birth
  • Assisted labor
  • Multiple pregnancy
  • Injuries from birth
  • Congenital malformation
  • Premature infants
  • Male infant sex
  • Restrictive uterine environment
  • Remaining in the prone position for a prolonged time
• During birth, the skull shape can change due to gravity and fluidity of the sutures as well as plasticity of brain.
• Unilateral coronal synostosis produces anterior plagiocephaly.
• Premature fusion of lambdoid suture causes synostotic posterior plagiocephaly.

COMMONLY ASSOCIATED CONDITIONS

Secondary craniosynostosis can occur in the following conditions:

• Rickets
• Hypothyroidism
• Microcephaly
• Status postshunt placement for hydrocephalus