Cone-shaped epiphyses in Japanese children

Cone‐shaped epiphyses (CSE) are reported in left‐hand radiographs of a sample of 1,399 otherwise normal Japanese children aged 5–11 years. CSE occurred in only three centers: distal thumb, mid‐index finger, and mid‐fifth finger. The overall frequency of 23% shows a female bias (32% to 16%), which disappears when mid‐5 cones are excluded. Chi‐squared analyses show significant gender bias for mid‐5 cones alone or in combination with the other phalanges, and show significant center associations: CSE in distal‐1 and/or mid‐2 are more common in association with mid‐5 cones than they are without mid‐5 cones. The CSE female bias in mid‐5 is essentially unchanged across age‐cohorts when bone‐age is controlled for precocity, and no significant trends in CSE frequency with age are noted for either gender.