Chondronecrosis of the hip - The protective role of the ossific nucleus inan animal model

The presence of the ossific nucleus and its role in reducing the risk of is chemic necrosis in developmental dysplasia of the hip remains a matter of c ontroversy. Ischemic necrosis of the preosseous capital femoral epiphysis, defined as chondronecrosis, was evaluated in a rabbit model. Histologic evi dence of chondronecrosis after casting in maximum abduction was greater in 1-day-old New Zealand White rabbits before the radiographic appearance of t he ossific nucleus, compared with 16-day-old New Zealand White rabbits with an ossific nucleus already present. This preliminary study supports the hy pothesis that the ossific nucleus may decrease the risk of intracapsular co mpressive ischemic injury to the developing capital femoral epiphysis in a rabbit model.