[New results of a modified acetabuloplasty after Lance combined with detorsion-varus-osteotomy (author's transl)].

The results of 254 Lance-acetabuloplasties in a modified technique combined withe detorsion-varus-osteotomy have been analysed. The children were operated upon in the years 1970-1974. Regarding the acetabulum the results were as follow: 1. In children between 1 and 6 years a normal acetabular index (as compared with the Normal Values of Tönnis and Brunken) was achieved in 78.3%, a slightly dysplastic index in 14.8%. In 6.6% a severe dysplasia remained. 2. In children between 6 and 10 years a normal acetabular index was found in 59.4%, a slightly dysplastic index in 24.3% and an index as classifies severe dysplasia in 16.2%. 3. In children older than 10 years and adults in 38.3% a normal Hip Value (Busse et al., Brückl et al.) was achieved, in 19.4% the value classifies a slight dysplasia, in 41.6% a severe dysplasia. These results show, that acetabuloplasty in the technique used here is a very effective method, especially in the first 6 years of life. But even in the older age groups significant improvement has been achieved. There for the indication of different operative techniques should be discussed again.