Pathology of Avascular Necrosis in the Femoral Head of Spontaneously Hypertensive Rats

Naturally occurring avascular necrosis in the femoral head of SHR, which resembles Perthes\u27 disease in man, was observed histologically. Of 96 epiphyses from 48 SHR, 34 epiphyses from 27 SHR showed a hallmark of necrosis during the period of 10 to 40 weeks after birth. The complete necrosis over the whole epiphyseal nucleus without revascularization was seen at the age of 10 and 15 weeks. Then the necrotic epiphysis was gradually repaired by the invasion of vascularized granulation tissue, and finally the healing of the necrosis was complete before the age of 40 weeks. An investigation into the pathogenesis of the healing infarction seemed that it would be of use in elucidating the cause of Perthes\u27 disease