“…Some common etiologic factors are idiopathic developmental abnormalities, 4,5,41,55 fracture, 5,20,39,41,49,55 and trauma to the epiphyseal growth plate prior to skeletal maturity. 4,5,20,39,41,49,55 Examples of less common etiologies include degenerative disorders, 5,20,39,41,49,55 Legg-Calvé-Perthes disease, 4,5,20,49 cancer or other neoplastic changes, 39,41,49 and infections. 20 …”