THE DEMOGRAPHICS OF SLIPPED CAPITAL FEMORAL EPIPHYSIS - AN INTERNATIONAL MULTICENTER STUDY

One thousand sis hundred thirty children with 1993 slipped capital fem oral epiphyses were reviewed; 41.2% were girls and 58.8% were boys. Th ere mere 47.5% white, 24.8% black, 16.9% Amerindian, 7.4% Indonesian-M alay, 2.1% Native Australian/Pacific Islands, and 1.3% Indo-Mediterran ean children. The diseased hip was unilateral in 77.7% and bilateral i n 22.3% of the children, and chronic in 85.5% and acute in 14.5% of th e children. Of the unilateral slips, 40.3% involved the right hip and 59.7% the left hip. The child's weight nas greater than or equal to th e ninetieth percentile in 63.2% of the children. The average age for t he girls and boys was 12 and 13.5 years. The age at diagnosis decrease d with increasing obesity. The youngest children were the Native Austr alian/Pacific Island children (11.8 years) and the oldest were the whi te and Indo-Mediterranean children (13 years). The Indonesian-Malay an d Indo-Mediterranean children were the lightest in weight, and the bla ck children the heaviest. The Indo-Mediterranean children had the high est proportion of boys (90.5%), and the Native Australian/Pacific Isla nd children the lowest (50%). The highest percentage of bilaterality w as in the Native Australian/Pacific Island children (38.2%), and the l owest in the Amerindian children (16.5%). The relative racial frequenc y of slipped capital femoral epiphysis compared with the white populat ion was 4.5 for the Polynesian, 2.2 for the black, 1.05 for the Amerin dian, 0.5 for the Indonesian-Malay, and 0.1 for the Indo-Mediterranean children. In children with unilateral involvement, the age at present ation was younger for those children in whom bilateral disease later d eveloped (12 versus 12.9 years old). In 82% of the children with seque ntial bilateral slips, the second slip was diagnosed within 18 months of the first slip.