Growth of short bones of the hand in children with Down's syndrome.

In this study, we report the elongation of the diaphyses of the short bones of the hand in an institutionalised sample of children with Down's syndrome. These diaphyses are significantly shorter than normal which is typical of other physical dimensions of individuals with Down's syndrome. Sex differences were generally lacking in diaphyseal lengths; this is in agreement with earlier reports. Pubescent spurts were not detected, but their absence cannot be certain. Roche (1965) reports the common absence of pubescent spurts in stature in children with Down's syndrome. However, only the magnitude of growth in stature of a small sample of these Down's children differed from normal; this dissimilarity was the result of differences in adult statures of normal and Down's individuals (Rarick, Wainer, Thissen and Seefeldt, 1975). Benda (1960) speculates that growth of the short bones of the hand stops early; thus, the pubescent spurt may be prevented by premature, epiphyseal closure. This would be in partial agreement with reports for stature (Roche, 1965). In this sample of children with Down's syndrome the extra chromosome, No. 21, appears to affect the growth of short bones of the hand before seven years of age. The diaphyses of short bones of the hand in these children are shorter than normal by seven years of age and significantly so after eleven years of age; but thereafter, these bones grow normally except for the absence of a pubescent spurt. This pattern is similar to reports of growth in length of other parts of the skeleton in children with Down's syndrome.