The Effect of the False Acetabulum on Femoral Proximal Medullary Canal in Unilateral Crowe Type IV Developmental Dislocation of the Hip.

The false acetabulum stimulated the development of the proximal femur in Crowe type IV DDH. The variation of the femoral proximal medullary canal in type IVA DDH mainly occurred at the metaphyseal and proximal diaphyseal levels, and that in type IVB DDH mainly occurred at the proximal diaphyseal level.