How can physicians determine whether an individual has attained adult height?

An X-ray of a bone, such as the wrist, will reveal whether a layer of epiphyseal cartilage still exists. If so, then additional growth can be expected. If the epiphyseal cartilage has all transformed into bone, leaving only an epiphyseal line marking the location where two areas of ossification fused together, then adult height has been reached. Most individuals reach their adult height between the ages of 17 and 21.