[Cone-shaped epiphyses in the phalanges of the hand--a statistical and experimental study]

To study the incidence of cone-shaped epiphysis (CSE) among Japanese children, roentgenograms of 1,391 hands in 985 children including 600 normal individuals (621 hands), 325 cases with various hand malformations (650 hands) and 60 cases with various systemic diseases (120 hands) were reviewed. A series of animal experiments was carried out to produce a similar pathological picture, by partially interrupting the circulation in the proximal portion of the tibia in young rabbits.

1. CSE was found in 13% of the normal individuals with female predominance (female/male = 2.3). The most common site was the middle phalanx of the little finger. In the hands with congenital malformation or systemic diseases, the overall incidence of CSE was not significantly higher than in normal hands, but the distribution and shape were somewhat different. 2. The animal experiments suggested that a circulatory disturbance of the growth plate may lead to the formation of CSE.