Some observations on the closure of the anterior fontanelle.

Early observers (Elsasser, 1843; Friedleben, 1860; Roger, 1859) have claimed that the dimensions of the anterior fontanelle of the human skull increase from the time of birth until about the age of 9 months, and that it is, as a rule, closed at the age of 18 months. Scammon (1923), reviewing this literature, challenged these observations on the grounds that the material studied involved European children of the poorer classes, many of them born prematurely, and many suffering from rickets. He argued that the observations did not necessarily apply to the 'better nourished and more rapidly growing American children', but he did not publish any figures of his own to substantiate his views. Zahorsky (1944) published observations on the date of closure of the anterior fontanelle in American children. Since his subjects were all seen in private practice they probably do not represent an accurate cross-section of the population. He estimated closure of the fontanelle by palpation and tried to correlate the time when it occurred with the type of feed the infants had received in the first four months of life. Aisenson (1950) examined 1,677 New York children in his health clinic and estimated that the mean age of closure of the anterior fontanelle was 13 * 5 months.