<P> Bone age is the degree of maturation of a child's bones . As a person grows from fetal life through childhood, puberty, and finishes growth as a young adult, the bones of the skeleton change in size and shape . These changes can be seen by x-ray . The "bone age" of a child is the average age at which children reach this stage of bone maturation . A child's current height and bone age can be used to predict adult height . For most people, their bone age is the same as their biological age but for some individuals, their bone age is a couple years older or younger . Those with advanced bone ages typically hit a growth spurt early on but stop growing early sooner while those with delayed bone ages hit their growth spurt later than normal . Kids who are below average height do not necessarily have a delayed bone age; in fact their bone age could actually be advanced which if left untreated, will stunt their growth . </P> <P> At birth, only the metaphyses of the "long bones" are present . The long bones are those that grow primarily by elongation at an epiphysis at one end of the growing bone . The long bones include the femurs, tibias, and fibulas of the lower limb, the humeri, radii, and ulnas of the upper limb (arm + forearm), and the phalanges of the fingers and toes . The long bones of the leg comprise nearly half of adult height . The other primary skeletal component of height is the spine and skull . </P>

What does a bone age x ray tell
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