Abstract
Since 1961 we have used the Spitzy shelf operation combined with a vertical flap osteotomy of the outer cortex of the ilium for early arthrosis secondary to acetabular dysplasia, subluxation, and dislocation. In 124 hips, followed for 10 (5–25) years, clinical improvement was maintained in 67/85 of patients who were operated on under the age of 30 and in 22/39 of patients treated after 30. However, less than half of the hips in the younger group and only one out of ten in the older group were symptom-free.