Developmental dysplasia of the hip (DDH) generally includes subluxation (partial dislocation) of the femoral head or complete dislocation of the femoral head from the true acetabulum and acetabular dysplasia. In a newborn with true congenital dislocation of the hip, the femoral head can often be dislocated and reduced into and out of the true acetabulum. In an older child, the femoral head remains dislocated and secondary changes develop in the femoral head and acetabulum.
