A, Osteonecrosis of left femoral head in 4-year-old girl after closed reduction of left congenital dislocation of hip at 6 months of age. B, At 10 years of age, now type II osteonecrosis is present, with premature lateral epiphyseal arrest and relative trochanteric overgrowth. C, At 13 years of age, after transfer of trochanter distally and anteriorly.