The key issues in determining whether a child with tall stature has a serious medical problem are determining in the first place whether the child is actually considerably taller in relation to his/her parents and secondly whether the child is growing at a normal or accelerated growth rate. Children who are unusually tall for their family and who have body disproportions ie. with long legs, arms or a big head may have a genetic cause for their tallness. Precocious sexual maturity is usually the cause of rapid growth in a phenotypically normal child as growth hormone excess (gigantism) is extremely rare. Refer to appropriate sections.
Children with normal growth velocity, an advanced bone age gives some prognosis to final height. If it is normal for chronological age, the child is likely to have a tall adult height. An advanced bone age suggests that an adult height in keeping with the biological parents will be achieved at an earlier age than normally expected.