Description
Children with achondroplasia experience a growth spurt in puberty, but as well as being only half that of control children, the spurt in achondroplasia is due entirely to sitting height, not leg length.
At birth, boys and girls with achondroplasia are on average 2.2 and 1.4 standard deviations below the median of the Argentine national references, respectively. But during infancy and childhood, height falls behind to a mean of -5 SDS in puberty and -6 SDS in final height for both sexes. In healthy children there is a marked growth spurt during puberty, but children with achondroplasia appear to lack this pubertal spurt in height.
This study aimed to use growth curve modelling to explore the growth spurt in height and the component segments of sitting height and leg length. Height and sitting height were measured longitudinally in 160 children with achondroplasia. Results from the growth height curves show a predicted height of 131 cm for boys and 120 cm for girls by the age of 19. Velocity curves showed that – although the peaks for sitting height in the two sexes were broadly similar in shape to those for height – those for leg length had no obvious peak.
References:
Cole TJ, del Pino M, Adamo P, Fano V Ann Hum Biol 2021;48(1):8–14 doi: 10.1080/03014460.2021.1883109