Abstract
1. Twenty-one cases of congenital dislocation of the hip were found on examination of 1,881 consecutive neonates on the first day of life, giving an incidence of eleven per 1,000 live births.
2. Insignificant high-pitched "clicks" were noted in 10 per cent of newborn children.
3. Conversion of half of the patients with hip dislocation to normal occurred during the first post-natal week.
4. Joint laxity was not a feature of the newborn with congenital dislocation of the hip.
5. Oestradiol, oestrone and oestriol were estimated in twenty-fourhour urine samples collected from sixteen patients with congenital dislocation of the hip and nineteen matched controls during the first six days of life. No significant differences in oestrogen output between the two groups were found.
6. The hypothesis that congenital dislocation of the hip is a result of an inborn error of oestrogen metabolism in the newborn is not supported.
