HISTOPATHOLOGIC ALTERATIONS OF RETINACULAR VESSELS AND OSTEONECROSIS

To probe into the pathogenesis of osteonecrosis of the femoral head, t he authors obtained 37 asymptomatic human femoral heads at autopsy; of these, 13 were cases of high dosage corticosteroid therapy (steroid g roup) and 24 were cases without steroid therapy (nonsteroid group), Th e steroid group included two asymptomatic cases of osteonecrosis incid entally recognized. These femoral heads then were studied histological ly and morphometrically using 2-mm stepwise tissue sections of the who le femoral head and serial sections to examine the histopathologic alt erations of superior retinacular arteries and veins in detail, There w as no significant difference in the luminal stenotic rate of the super ior retinacular arteries between the steroid and nonsteroid groups. Ho wever, the draining veins morphometrically were more stenotic or oblit erated in the steroid group than were those in the nonsteroid group, I n fact, the number of stenotic veins was significantly greater in the steroid group, These findings indicate that the stenotic changes of th e draining veins may participate in the development and progression of steroid induced osteonecrosis of the femoral head.