Superior fracture-dislocation of the hip.

A case of superior fracture-dislocation of the hip following a low-energy injury is reported. The direction of the dislocation is uncommon. Radiological investigation was delayed for 5 months and then showed the appearances of a radiologically perfect false acetabulum. The fracture-dislocation was a type IV with an associated fracture of the femoral neck, an injury which is expected to produce a high rate of avascular necrosis of the femoral head. However, bone scans suggested that the femoral head was viable.