Anatomy word of the month: fontanelle

A “little fountain or spring” (derived from the Latin). In laymen’s terms, the “soft spots” of a baby’s head are membranous areas between the skull bones that allow changes in shape of the head as it traverses the birth canal. Minute pulsations of these areas, reflecting the heartbeat, gave rise to its name. The fontanelles gradually are transformed into bone after birth leaving the cranium a single mass of bone with only sutures, lines of merger, as signs of its origin from several separate bones.