1. In children the Trendelenburg sign persists even though a suitable shelf is apparent when constructed with the hip in situ.
2. The shelf should be made from acetabular tissue when possible,—that is, the shelf should be at the upper part of the acetabulum with the roof turned down and the cartilage intact. The roof should be nearly horizontal.
3. The head of the femur must be pulled down in order to construct such a shelf.
4. All obstructing tissue should be removed but, since there are degenerative processes occurring from a misshaped head, it would seem unwise to remove much fibrous tissue from the acetabular cavity.
5. If there have been two failures to secure manual reduction in young children, it would seem sound to do an open reduction before the acetabular roof disappears.
6. In spite of the fact that the shelf has melted away in many of these cases, the hips are more stable than when there is no good false acetabulum or no acetabular roof present.