Necrosis of the proximal epiphyseal plate cartilage of the femur following detachment of the perichondral ring. Its relationship to the etiology of proximal epiphysiolysis of the femur.

A histological study of the proximal epiphyseal plate cartilage of rabbit femurs following detachment of the perichondral ring was performed. 15 animals were used, 5 of which being controls. Slight to severe necrotic changes in the plate were present in 9 out of 10 animals. In severe necrosis there was formation of fissures similar to those seen in human femoral epiphysiolysis. The necrosis was considered ischemic in nature and due to the detachment of the perichondral ring with involvement of the blood supply for the femoral epiphysis. Also the epiphyseal and metaphyseal bone marrow and bone tissue, as well as the articular cartilage, presented necrotic changes in a few animals. Such necrosis of the epiphyseal plate may be a factor in the pathogenesis of human proximal epiphysiolysis of the femur.