The frequency of appearance of transverse lines in the tibia in relation to childhood illnesses

The hypothesis that transverse lines of increased density in growing bones are caused by illnesses and other traumas of childhood was investigated using tibial x-rays and medical records of 107 boys and 94 girls in the Fels longitudinal series. There is not a one to one relationship between even severe illnesses and line formation. The frequency of appearance of lines at each age interval, one month through fourteen years, was calculated for both sexes separately and combined, in order to show periods of maximum formation. That transverse lines are “growth arrest” lines which cause ultimate growth retardation was discounted since no significant difference in finally attained adult stature was noted between heavily and lightly lined subjects.