[Statistical analysis of congenital hip dysplasia is not possible in the first months of life! (author's transl)].

The question whether congenital hip dysplasia can be defined statistically has been raised again by Kristen, Dorda and Zweymüller. These authors believe that a definition is possible by statistical methods. Compiling a normal material for statistical evaluation, however, needs a clinical separation of normal and dysplastic joints before. And this--in our opinion--is not possible during the first half year of life. The only possible way is a long-term follow-up. In our own investigation children with higher acetabular indices have been followed up to 5 years and more. Only by this clinical evaluation is it possible to say which joints have developed normally and which have not. This is a clinical diagnosis of hip dysplasia, not a statistical.