short stature

Childhood Short Stature
Growth disturbances manifest as abnormal absolute height or growth velocity.
Short stature is defined as height that is two standard deviations below the mean height for age and sex (less than the 3rd percentile) or more than two standard deviations below the midparental height.


Growth velocity disorder is defined as an abnormally slow growth rate, which may manifest as height deceleration across two major percentile lines on the growth chart. 

Physiology of growth
three phases
after birth: infancy, childhood and pubertal growth
.1st year 25cm/year
2-3 year 7.5-13cm/year
7cm/year at 3-4 year s and
6cm/year at 5-6 years. It then remains at 4-6cm/year
until puberty occurs when their growth will slow to about 4 cm/year
Girls have their peak height velocity at early puberty, 9cm/year .
Boys reach their peak height velocity during midpuberty , with growth rate 10cm/year
In male skeletal growth till 17years while in female till age of 14 years
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Type of short stature
A-Genetic short stature/Familial short stature
the most common type
 a condition characterized by
1- height below the third percentile for age,
2- normal annual growth rate
3- normal bone age,
4- family history of short stature,
5- expected adult height below the third percentile,
6- normal onset of puberty,
7- and normal result to findings on physical examination
8- no endocrine abnormalities.,

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