Height is the distance from the top of the head to the bottom of the feet whilst standing. Ht is shorthand for Height. Length (L) is used for infants reflecting that they cannot stand supine. Note that L can also be shorthand for Left.
Femur length (FL) is an U/S measure of the length of the femur bone (i.e. thigh bone, upper leg bone), and helps exclude dwarfism in the fetus.
Short stature is height which is 2 standard deviations below the mean for age and gender, thereby corresponding to the shortest 2.3% of individuals. This corresponds to adult men <170cm, and adul women <157cm. It can be caused by growth hormone deficiency
In newborns, the average length is 22" (50cm). The normal range is 18-22" (45.7-60cm)