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Growth is a complex process that involves the interaction of
multiple, diverse factors and represents the sum of these influences
on cell replication and programmed cell death (apoptosis) and on
cell differentiation. Growth is ultimately governed by the genome
of a person and its interactions with external factors, such as
nutrition and psychosocial well-being. Linear height growth may
occur as a continuous process or with periodic bursts of growth
and arrest.1-3During 1 year of growth monitoring,
there may be marked seasonal variations of height and weight gain
with several monthly bursts of weight and then height growth.4 Despite
the complexity, healthy children usually grow linearly in a remarkably
predictable manner. Change from a normal growth pattern often is
the first manifestation of a disease, either an endocrine or a nonendocrine
disorder that can involve almost any organ system. Frequent and
accurate assessment of growth therefore is of primary importance
in the care of children.
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Growth rates differ during intrauterine life, early and middle
childhood, and adolescence. During gestation, growth averages 1.2
to 1.5 cm per week but increases dramatically to a midgestational
peak of 2.5 cm per week with a decline to 0.5 cm per week immediately
before birth. Growth velocity during the first 2 years of life averages
about 15 cm per year and slows to approximately 6 cm per year during
middle childhood. The peak height velocity during the pubertal growth
spurt is 7 to 11 cm/yr. The time of puberty onset and consequently
the age at the pubertal growth spurt varies among healthy children. On
average, girls begin and complete puberty earlier than do boys and
thus stop growing earlier (at 14 to 15 years of age compared with 16
to 17 years for boys). This accounts for the approximately 13-cm
difference in the adult heights of women and men. Despite variations
in the age of onset of puberty, among most healthy children, final
height is not influenced by the chronological time of onset of the
pubertal growth spurt. Growth ceases after fusion of long bone and
vertebral epiphyses. This occurs when chondrocyte proliferation
in the growth plate slows and senescent changes occur in a process
seemingly intrinsic to the biology of the growth plate.5,6
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Because heredity is a significant determinant of growth, it is
important to relate a patient’s height to that of siblings
and parents. Tanner and associates developed a method by which stature
of children can be assessed relative to midparental height. Mean
parental height is calculated, and 6.5 cm is added for boys or subtracted
for girls. The 2-SD (standard deviation) range for this calculated
parental target height is approximately 10 cm. The possibility of
an underlying pathological condition must be considered when a child’s
growth pattern clearly deviates from that of the parents.7
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Accurate height measurements are necessary for the evaluation
of growth. Measurement of supine length should be used for children
younger ...