GROWTH-PATTERN IN THE APERT SYNDROME

In this paper, we demonstrate that a discernible and unique growth pat tern characterizes the Apert syndrome. The keys to understanding Apert newborn measurement values are brain size and cranial configuration. Both true megalencephaly and coronal synostosis are present at birth. Thus, the head is unusually heavy and the cranium is disproportionatel y high. Mean newborn length and weight are above the normal 50th centi le. Of our newborn patients, 16% exceeded 4,000 g in weight. Preterm i nfants were appropriate or slightly large for gestational age. A bipha sic linear growth pattern was found. In childhood, deceleration of lin ear growth occurs so that most values fall between the 5th and 50th ce ntiles. From adolescence to adulthood, deceleration becomes more prono unced. This 2-step linear growth deceleration results in large measure from rhizomelic shortness of the lower limbs. Puberty takes place wit hin the normal time frame. Although a disproportionate amount of the m egalencephaly accounts for the dramatic increase in head height, the w idely patent midline calvarial defect, allowing the brain to expand an teriorly into the metopic area, and some increase in the head breadth permit the mean head circumference at birth to normalize slightly abov e the 50th centile. During the growth period, the head circumference w as studied in surgically unoperated Apert patients from the 1960s and earlier. The natural history of the growing cranium consists of gradua l deceleration in head circumference from slightly above the 50th cent ile at birth to within or at - 2 SD later on. (C) 1993 Wiley-Liss, Inc .